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CORE MODULE SYLLABUS FOR ENVIRONMENTAL STUDIES, FOR UNDER GRADUATE COURSES OF ALL BRANCHES, OF HIGHER EDUCATION, , Vision, The importance of environmental science and environmental studies cannot be, disputed. The need for sustainable development is a key to the future of mankind., Continuing problems of pollution, loss of forget, solid waste disposal, degradation of, environment, issues like economic productivity and national security, Global warming,, the depletion of ozone layer and loss of biodiversity have made everyone aware of, environmental issues. The United Nations Coference on Environment and Development, held in Rio de Janerio in 1992 and world Summit on Sustainable Development at, Johannesburg in 2002 have drawn the attention of people around the globe to the, deteriorating condition of our environment. It is clear that no citizen of the earth can, afford to be ignorant of environment issues. Environmental management has captured the, attention of health care managers. Managing environmental hazards has become very, important., Human beings have been interested in ecology since the beginning of civilization., Even our ancient scriptures have emphasized about practices and values of environmental, conservation. It is now even more critical than ever before for mankind as a whole to, have a clear understanding of environmental concerns and to follow sustainable, development practices., India is rich in biodiversity which provides various resources for people. It is also, basis for biotechnology., , Only about 1.7 million living organisms have been diescribed and named, globally. Still manay more remain to be identified and described. Attempts are made to, , I
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conserve them in ex-situ and in-situ situations. Intellectual property rights (IPRs) have, become importanat in a biodiversity-rich country like India to protect microbes, plants, and animals that have useful genetic properties. Destruction of habitats, over-use of, energy resource and environmental pollution have been found to be responsible for the, loss of a large number of life-forms. It is feared that a large proportion of life on earth, may get wiped out in the near future., Inspite of the deteriorating status of the environment, study of environment have, so far not received adequate attention in our academic programmes. Recognizing this, the, Hon’ble Supreme Court directed the UGC to introduce a basic course on environment at, every level in college education. Accordingly, the matter was considered by UGC and it, was decided that a six months compulsory core module course in environmental studies, may be prepared and compulsorily implemented in all the University/Colleges of India., The experts committee appointed by the UGC has looked into all the pertinent, questions, issues and other relevant matters. This was followed by framing of the core, module syllabus for environmental studies for undergraduate courses of all branches of, Higher Education. We are deeply conscious that there are bound to be gaps between the, ideal and real. Geniune endeavour is required to minimize the gaps by intellectual and, material inputs. The success of this course will depend on the initiative and drive of the, teachers and the receptive students., , SYLLABUS, Unit 1 : Multidisciplinary nature of environmental studies, Definition, scope and importance, (2 lectures), Need for public awareness., , II
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Unit 2 : Natural Resources :, Renewable and non-renewable resources :, Natural resources and associated problems., a), , Forest resources : Use and over-exploitation, deforestation, case studies., Timber extraction, mining, dams and their effects on forest and tribal people., , b), , Water resources : Use and over-utilization of surface and ground water,, floods, drought, conflicts over water, dams-benefits and problems., , c), , Mineral resources : Use and exploitation, environmental effects of extracting, and using mineral resources, case studies., , d), , Food resources : World food problems, changes caused by agriculture and, overgrazing, effects of modern agriculture, fertilizer-pesticide problems, water, logging, salinity, case studies., , e), , Energy resources : Growing energy needs, renewable and non renewable, energy sources, use of alternate energy sources. Case studies., , f), , Land resources : Land as a resource, land degradation, man induced, landslides, soil erosion and desertification., , •, , Role of an individual in conservation of natural resources., , •, , Equitable use of resoureces for sustainable lifestyles., (8 lectures), , Unit 3 : Ecosystems, , •, , Concept of an ecosystem., , III
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•, , Structure and function of an ecosystem., , •, , Producers, consumers and decomposers., , •, , Energy flow in the ecosystem., , •, , Ecological succession., , •, , Food chains, food webs and ecological pyramids., , •, , Introduction, types, characteristic features, structure and function of the, following ecosystem :a. Forest ecosystem, b. Grassland ecosystem, c. Desert ecosystem, d. Aquatic ecosystems (ponds, streams, lakes, rivers, oceans, estuaries), (6 lectures), , Unit 4 : Biodiversity and its conservation, •, , Introduction – Definition : genetic, species and ecosystem diversity., , •, , Biogeographical classification of India, , •, , Value of biodiversity : consumptive use, productive use, social, ethical, aesthetic, and option values, , •, , Biodiversity at global, National and local levels., , •, , Inida as a mega-diversity nation, , IV
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•, , Hot-sports of biodiversity., , •, , Threats to biodiversity : habitat loss, poaching of wildlife, man-wildlife conflicts., , •, , Endangered and endemic species of India, , •, , Conservation of biodiversity : In-situ and Ex-situ conservation of biodiversity., (8 lectures), , Unit 5 : Environmental Pollution, Definition, •, , •, , Cause, effects and control measures of :a., , Air pollution, , b., , Water pollution, , c., , Soil pollution, , d., , Marine pollution, , e., , Noise pollution, , f., , Thermal pollution, , g., , Nuclear hazards, , Solid waste Management : Causes, effects and control measures of urban and, industrial wastes., , •, , Role of an individual in prevention of pollution., , •, , Pollution case studies., , •, , Diaster management : floods, earthquake, cyclone and landslides., (8 lectures), , V
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Unit 6 : Social Issues and the Environment, •, , From Unsustainable to Sustainable development, , •, , Urban problems related to energy, , •, , Water conservation, rain water harvesting, watershed management, , •, , Resettlement and rahabilitation of people; its problems and concerns. Case, Studies, , •, , Environmental ethics : Issues and possible solutions., , •, , Climate change, global warming, acid rain, ozone layer depletion, nuclear, accidents and holocaust. Case Studies., , •, , Wasteland reclamation., , •, , Consumerism and waste products., , •, , Environment Protection Act., , •, , Air (Prevention and Control of Pollution) Act., , •, , Water (Prevention and control of Pollution) Act, , •, , Wildlife Protection Act, , •, , Forest Conservation Act, , •, , Issues involved in enforcement of environmental legislation., , •, , Public awareness., (7 lectures), , Unit 7 : Human Population and the Environment, •, , Population growth, variation among nations., , •, , Population explosion – Family Welfare Programme., , VI
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•, , Environment and human health., , •, , Human Rights., , •, , Value Education., , •, , HIV/AIDS., , •, , Women and Child Welfare., , •, , Role of Information Technology in Environment and human health., , •, , Case Studies., (6 lectures), , Unit 8 : Field work, •, , Visit to a local area to document environmental assetsriver/forest/grassland/hill/mountain, , •, , Visit to a local polluted site-Urban/Rural/Industrial/Agricultural, , •, , Study of common plants, insects, birds., , •, , Study of simple ecosystems-pond, river, hill slopes, etc. (Field work Equal to 5, lecture hours), , VII
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SIX MONTHS COMPULSORY CORE MODULE COURSE IN, ENVIRONMENTAL STUDIES : FOR UNDERGRADUATES, Teaching Methodologies, , The core Moudle Syllabus for Environment Studies includes class room teaching, and Field Work. The syllabus is divided into eight units covering 50 lectures. The first, seven units will cover 45 lectures which are class room based to enhance knowledge, skills and attitute to environment. Unit eight is based on field activites which will be, covered in five lecture hours and would provide student first hand knowledge on varios, local environmental aspects. Field experience is one of the most effective learning tools, for environmental concerns. This moves out of the scope of the text book mode of, teaching into the realm of real learning in the field, where the teacher merely acts as a, catalyst to interpret what the student observes or discovers in his/her own environment., Field studies are as essential as class work and form an irreplaceable synergistic tool in, the entire learning process., , Course material provided by UGC for class room teaching and field activities be, utilized., , The universities/colleges can also draw upon expertise of outside resource persons, for teaching purpose., , Environmental Core Module shall be integrated into the teaching programmes of, all undergraduate courses., , Annual System :, , The duration of the course will be 50 lectures. The exam will be, , conducted along with the Annual Examination., , VIII
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Semester System : The Environment course of 50 lectures will be conducted in the, second semester and the examination shall be conducted at the end of the second, semester., , Credt System :, , The course will be awarded 4 credits., , Exam Pattern :, , In case of awarding the marks, the question paper should, , carry 100 marks. The structure of the question paper being :, , Part-A, Short answer pattern, , -, , 25 marks, , Part-B, Essay type with inbuilt choice, , -, , 50 marks, , Part-C, Field Work, , -, , 25 marks, , IX
Page 11 : REFERENCE, a), , Agarwal, K.C. 2001 Environmental Biology, Nidi Publ. Ltd. Bikaner., , b), , Bharucha Erach, The Biodiversity of India, Mapin Publishing Pvt. Ltd.,, Ahmedabad – 380 013, India, Email:
[email protected] (R), , c), , Brunner R.C., 1989, Hazardous Waste Incineration, McGraw Hill Inc. 480p, , d), , Clark R.S., Marine Pollution, Clanderson Press Oxford (TB), , e), , Cunningham, W.P. Cooper, T.H. Gorhani, E & Hepworth, M.T. 2001,, Environmental Encyclopedia, Jaico Publ. House, Mumabai, 1196p, , f), , De A.K., Environmental Chemistry, Wiley Eastern Ltd., , g), , Down to Earth, Centre for Science and Environment (R), , h), , Gleick, H.P. 1993. Water in crisis, Pacific Institute for Studies in Dev.,, Environment & Security. Stockholm Env. Institute Oxford Univ. Press. 473p, , i), , Hawkins R.E., Encyclopedia of Indian Natural History, Bombay Natural, History Society, Bombay (R), , j), , Heywood, V.H & Waston, R.T. 1995. Global Biodiversity Assessment., Cambridge Univ. Press 1140p., , k), , Jadhav, H & Bhosale, V.M. 1995. Environmental Protection and Laws., Himalaya Pub. House, Delhi 284 p., , l), , Mckinney, M.L. & School, R.M. 1996. Environmental Science systems &, Solutions, Web enhanced edition. 639p., , m), , Mhaskar A.K., Matter Hazardous, Techno-Science Publication (TB), , n), , Miller T.G. Jr. Environmental Science, Wadsworth Publishing Co. (TB), , o), , Odum, E.P. 1971. Fundamentals of Ecology. W.B. Saunders Co. USA, 574p, , p), , Rao M N. & Datta, A.K. 1987. Waste Water treatment. Oxford & IBH Publ., Co. Pvt. Ltd. 345p., , q), , Sharma B.K., 2001. Environmental Chemistry. Geol Publ. House, Meerut, , r), , Survey of the Environment, The Hindu (M), , s), , Townsend C., Harper J, and Michael Begon, Essentials of Ecology, Blackwell, Science (TB), , X
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t), , Trivedi R.K., Handbook of Environmental Laws, Rules Guidelines,, Compliances and Stadards, Vol I and II, Enviro Media (R), , u), , Trivedi R. K. and P.K. Goel, Introduction to air pollution, Techno-Science, Publication (TB), , v), , Wanger K.D., 1998 Environmental Management. W.B. Saunders Co., Philadelphia, USA 499p, (M) Magazine, (R) Reference, (TB) Textbook, , XI
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Textbook for, , Environmental Studies, For Undergraduate Courses, of all Branches of Higher Education, , Erach Bharucha, for, , University Grants Commission, , Natural Resources, , Preliminary Pages.p65, , i, , 1, , 4/9/2004, 5:06 PM
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Vision, The importance of Environmental Studies cannot be disputed. The need for sustainable development is a key to the future of mankind. The degradation of our environment is linked to continuing, problems of pollution, loss of forest, solid waste disposal, issues related to economic productivity, and national as well as ecological security. The increasing levels of global warming, the depletion of, the ozone layer and a serious loss of biodiversity have also made everyone aware of growing environmental concerns. The United Nations Conference on Environment and Development held in Rio, De Janero in 1992, and the World Summit on Sustainable Development at Zoharbex in 2002 have, drawn the attention of people around the globe to the developing condition of our environment. It, is clear that no citizen of the earth can afford to be ignorant of environmental issues. Environmental, management has become a part of the health care sector. Managing environmental hazards and, preventing possible disasters has become an urgent need., Human beings have been interested in ecology since the beginning of civilization. Even our ancient, scriptures have included practices and values related with environmental conservation. It is now, even more critical than ever before for mankind as a whole to have a clear understanding of, environmental concerns and to follow sustainable development practices., India is rich in biodiversity which provides various resources for people. It is also the basis for biotechnological development. Only about 1.8 million living organisms have been described and named, globally. Still many more remain to be identified and described. Attempts are made to conserve, them in ex-situ and in-situ situation. Intellectual Property Rights (IPRs) have become important in a, biodiversity rich country like India to protect microbes, plants and animals that have useful genetic, properties. Destruction of habitats, over use of energy resources and environmental pollution have, been found to be responsible for the loss of a large number of life forms. It is feared that a large, proportion of life on earth may get wiped out in the near future., In spite of the developing status of the environment, the formal study of environment has so far not, received adequate attention in our academic performances. Recognisation thus the Hon’ble Supreme Court directed the UGC to introduce a basic course on environment for every student., Accordingly the matter was considered by the UGC and it was decided that a six months compulsory core module course in environmental studies may be prepared and compulsorily implemented, in all the Universities/ Colleges in India., The Expert Committee appointed by the UGC has looked into all the pertinent questions, issues and, other relevant matters. This was followed by framing of the Core Module Syllabus for Environmental Studies for undergraduate courses of all branches of Higher Education. The Committee is deeply, conscious that there are bound to be gaps between what is considered ideal and the present, syllabus. The Committee has attempted to minimize the gaps by intellectual and material inputs., The success of this course will however depend on the initiative and drive of the teachers and their, students., Members of the Curriculum Development Committee, , Natural Resources, , Preliminary Pages.p65, , iii, , 3, , 4/9/2004, 5:06 PM
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Six Months Compulsory Core Module Course, in Environmental Studies: for Undergraduate Students, Teaching Methodologies, The Core Module Syllabus for Environmental Studies includes classroom teaching and fieldwork., The syllabus is divided into eight units covering 50 lectures. The first seven units which will cover 45, lectures are classroom teaching based to enhance knowledge skilled and attitude to environment., Unit eight is based on field activities and would be covered over five lecture hours and would, provide students with first hand knowledge on various local environmental aspects. Field experience is one of the most effective learning tools for environmental concerns. This moves out of the, scope of the textbook mode of teaching, into the realm of real learning in the field, where the, teacher acts as a catalyst to interpret what the student observes or discovers in his/her own environment. Field studies area as essential as class work and form an irreplaceable synergistic tool in the, entire learning process., The course material provided by UGC for class room teaching and field activities should be utilised., The Universities/ colleges can draw upon expertise of outside resource persons for teaching purposes., The Environmental Core Module shall be integrated into the teaching programs of all undergraduate courses., Annual System: The duration of the course will be 50 lectures. The exam will be conducted along, with the Annual Examination., Semester System: the Environment course of 50 lectures will be conducted in the second semester, and the examinations shall be conducted at the end of the second semester., Credit System: The core course will be awarded 4 credits, Exam Pattern: In case of awarding the marks the question paper should carry 100 marks. The, structure of the question paper being:, Part A, Short answer pattern, Part B, Essay type built choice, Part C, Field Work, , - 25 marks, - 50 marks, - 25 marks, , Natural Resources, , Preliminary Pages.p65, , v, , 5, , 4/9/2004, 5:06 PM
Page 19 : Further Readings, 1. Agarwal KC, 2001. Environmental Biology, Nidi Publishers Ltd. Bikaner., 2. Bharucha Erach, 2003. The Biodiversity of India, Mapin Publishing Pvt. Ltd, Ahmedabad – 380013,, India. Email:
[email protected], 3. Brunner RC, 1989, Hazardous Waste Incineration, McGraw Hill Inc. 480pgs., 4. Clark RS, Marine Pollution, Clanderson Press, Oxofrd (TB)., 5. Cunningham WP, Cooper TH, Gorhani E & Hepworth MT, 2001. Environmental Encyclopaedia,, Jaico Publishing House, Mumbai, 1196pgs., 6. De AK, Environmental Chemistry, Wiley Eastern Ltd., 7. Down to Earth, Center for Science and Environment (R), 8. Gleick HP, 1993. Water in Crisis, Pacific Institute for Studies in Development, Environment and, Security. Stockholm Environmental Institute, Oxford University Press, 473pgs., 9. Hawkins RE, Encyclopedia of Indian Natural History, Bombay Natural History Society, Bombay, (R), 10. Heywood VH, and Watson RT, 1995. global Biodiversity Assessment. Cambridge University, Press 1140pgs., 11. Jadhav H and Bhosale VM, 1995. Environmental Protection and Laws. Himalaya Publishing, House, Delhi 284pgs., 12. Mckinney ML and Schoch RM, 1996. Environmental Science Systems and Solutions. Web enhanced edition, 639pgs., 13. Mhaskar AK, Matter Hazardous, Techno-Science Publications (TB), 14. Miller TG, Jr. Environmental Science, Wadsworth Publishing CO. (TB), 15. Odum EP, 1971. Fundamentals of Ecology. WB Saunders Co. USA, 574pgs., 16. Rao MN and Datta AK, 1987. Waste Water Treatment. Oxford and IBH Publishing Co. Pvt. Ltd., 345pgs., , Environmental Studies for Undergraduate Courses, , vi, , Preliminary Pages.p65, , 6, , 4/9/2004, 5:06 PM
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Contents, PREFACE, , xiii, , FOREWORD, , xv, , ACKNOWLEDGEMENTS, , xvi, , UNIT 1: THE MULTIDISCIPLINARY NATURE OF ENVIRONMENTAL, STUDIES, 1.1, , DEFINITION, SCOPE AND IMPORTANCE, 1.1.1 Definition, 1.1.2 Scope, 1.1.3 Importance, , 1.2, , NEED FOR PUBLIC AWARENESS, 1.2.1 Institutions in Environment, 1.2.2 People in Environment, , 3, 3, 3, 5, 8, 9, 12, , UNIT 2: NATURAL RESOURCES, 2.1 INTRODUCTION, , 16, , 2.2 RENEWABLE AND NON-RENEWABLE RESOURCES, 2.2.1 Natural resources and associated problems, 2.2.2 Non-renewable resources, 2.2.3 Renewable resources, a. Forest Resources: Use and over-exploitation, deforestation, case studies., Timber extraction, mining, dams and their effects on forests and tribal people, b. Water Resources: Use and over-utilisation of surface and ground water,, floods, drought, conflicts over water, dams – benefits and problems., c. Mineral Resources: Use and exploitation, environmental effects of extracting, and using mineral resources, case studies., d. Food Resources: World food problems, Changes in landuse by agriculture and, grazing, Effects of modern agriculture, Fertilizer/ pesticide problems,, Water logging and salinity, e. Energy Resources: Increasing energy needs, Renewable/ non renewable,, Use of Alternate energy sources, Case studies, f. Land resources: Land as a resource, land degradation, man-induced land-slides,, soil erosion and desertification., , 20, 20, 22, 22, 23, , Natural Resources, , vii, , Preliminary Pages.p65, , 7, , 4/9/2004, 5:06 PM, , 26, 30, 32, , 35, 48
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2.3 ROLE OF AN INDIVIDUAL IN CONSERVATION OF NATURAL RESOURCES, , 50, , 2.4 EQUITABLE USE OF RESOURCES FOR SUSTAINABLE LIFESTYLES, , 51, , UNIT 3: ECOSYSTEMS, 3.1 Concept of an ecosystem, 3.1.1 Understanding ecosystems, 3.1.2 Ecosystem degradation, 3.1.3 Resource utilisation, , 54, 55, 55, 56, , 3.2 Structure and functions of an ecosystem, , 56, , 3.3 Producers, consumers and decomposers, , 57, , 3.4 Energy flow in the ecosystem, 3.4.1 The water cycle, 3.4.2 The Carbon cycle, 3.4.3 The Oxygen cycle, 3.4.4 The Nitrogen cycle, 3.4.5 The energy cycle, 3.4.6 Integration of cycles in nature, , 58, 58, 59, 60, 60, 61, 62, , 3.5 Ecological succession, , 62, , 3.6 Food chains, Food webs and Ecological pyramids, 3.6.1 The food chains, 3.6.2 The food webs, 3.6.3 The ecological pyramids, , 62, 62, 63, 63, , 3.7 Introduction, Types, Characteristic features, Structure and functions, 3.7.1 Forest ecosystem, 3.7.2 Grassland ecosystem, 3.7.3 Desert ecosystem, 3.7.4 Aquatic ecosystems (ponds, lakes, streams, rivers, estuaries, oceans), , 63, 65, 70, 74, 75, , UNIT 4: BIODIVERSITY AND ITS CONSERVATION, 4.1 INTRODUCTION – DEFINITION: GENETIC, SPECIES, ECOSYSTEM DIVERSITY, 4.1.1 Genetic diversity, 4.1.2 Species diversity, 4.1.3 Ecosystem diversity, , 82, 82, 82, 83, , 4.2 BIOGEOGRAPHIC CLASSIFICATION OF INDIA, , 84, , Environmental Studies for Undergraduate Courses, , viii, , Preliminary Pages.p65, , 8, , 4/9/2004, 5:06 PM
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4.3 VALUE OF BIODIVERSITY: CONSUMPTIVE, PRODUCTIVE USE, SOCIAL, ETHICAL,, AESTHETIC AND OPTION VALUES, 4.3.1Consumptive value, 4.3.2 Productive value, 4.3.3 Social value, 4.3.4 Ethical value, 4.3.5 Aesthetic value, 4.3.6 Option value, , 84, 85, 86, 86, 88, 88, 88, , 4.4 BIODIVERSITY AT GLOBAL, NATIONAL AND LOCAL LEVELS, , 88, , 4.5 INDIA AS A MEGA DIVERSITY NATION, , 89, , 4.6 HOTSPOTS OF BIODIVERSITY, , 90, , 4.7 THREATS TO BIODIVERSITY: HABITAT LOSS, POACHING OF WILDLIFE,, MAN-WILDLIFE CONFLICTS, , 91, , 4.8 ENDANGERED AND ENDEMIC SPECIES OF INDIA, 4.8.1 Common Plant species, 4.8.2 Common Animal species, , 94, 94, 99, , 4.9 CONSERVATION OF BIODIVERSITY: IN-SITU AND EX-SITU, 4.9.1 In-situ conservation, 4.9.2 Ex-situ conservation, , 104, 104, 108, , UNIT 5: ENVIRONMENTAL POLLUTION, 5.1 DEFINITION, , 112, , 5.2 CAUSES, EFFECTS AND CONTROL MEASURES OF:, , 113, , 5.2.1 Air Pollution, , 113, , 5.2.2 Water Pollution, , 123, , 5.2.3 Soil Pollution, , 131, , 5.2.4 Marine Pollution, , 135, , 5.2.5 Noise Pollution, , 140, , 5.2.6 Thermal Pollution, , 142, , 5.2.7 Nuclear hazards, , 143, , 5.3 SOLID WASTE MANAGEMENT: CAUSES, EFFECTS AND CONTROL MEASURES, OF URBAN AND INDUSTRIAL WASTE, , 145, , 5.4 ROLE OF INDIVIDUALS IN POLLUTION PREVENTION, , 150, , Natural Resources, , Preliminary Pages.p65, , ix, , 9, , 4/9/2004, 5:06 PM
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5.5 POLLUTION CASE STUDIES, , 153, , 5.6 DISASTER MANAGEMENT: FLOODS, EARTHQUAKES, CYCLONES, LANDSLIDES, , 156, , UNIT 6: SOCIAL ISSUES AND THE ENVIRONMENT, 6.1 FROM UNSUSTAINABLE TO SUSTAINABLE DEVELOPMENT, , 165, , 6.2 URBAN PROBLEMS RELATED TO ENERGY, , 167, , 6.3 WATER CONSERVATION, RAIN WATER HARVESTING, WATERSHED, MANAGEMENT, 6.3.1 Water conservation, 6.3.2 Rain water harvesting, 6.3.3 Watershed management, , 168, 168, 170, 171, , 6.4 RESETTLEMENT AND REHABILITATION OF PEOPLE; ITS PROBLEMS, AND CONCERNS. CASE STUDIES, , 172, , 6.5 ENVIRONMENTAL ETHICS: ISSUES AND POSSIBLE SOLUTIONS, 6.5.1 Resource consumption patterns and the need for their equitable utilisation, 6.5.2 Equity – Disparity in the Northern and Southern countries, 6.5.3 Urban – rural equity issues, 6.5.4 The need for Gender Equity, 6.5.5 Preserving resources for future generations, 6.5.6 The rights of animals, 6.5.7 The ethical basis of environment education and awareness, 6.5.8 The conservation ethic and traditional value systems of India, , 173, 173, 175, 175, 175, 176, 177, 178, 181, , 6.6 CLIMATE CHANGE, GLOBAL WARMING, ACID RAIN, OZONE LAYER DEPLETION,, NUCLEAR ACCIDENTS AND NUCLEAR HOLOCAUST. CASE STUDIES, 6.6.1 Climate change, 6.6.2 Global warming, 6.6.3 Acid rain, 6.6.4 Ozone layer depletion, 6.6.5 Nuclear Accidents and Nuclear Holocaust, , 182, 182, 183, 184, 185, 186, , 6.7 WASTELAND RECLAMATION, , 187, , 6.8 CONSUMERISM AND WASTE PRODUCTS, , 189, , 6.9 ENVIRONMENT PROTECTION ACT, , 193, , 6.10 AIR (PREVENTION AND CONTROL OF POLLUTION) ACT, , 194, , 6.11 WATER (PREVENTION AND CONTROL OF POLLUTION) ACT, , 196, , Environmental Studies for Undergraduate Courses, , x, , Preliminary Pages.p65, , 10, , 4/9/2004, 5:06 PM
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6.12 WILDLIFE PROTECTION ACT, , 197, , 6.13 FOREST CONSERVATION ACT, , 199, , 6.14 ISSUES INVOLVED IN ENFORCEMENT OF ENVIRONMENTAL LEGISLATION, 6.14.1Environment Impact Assessment (EIA), 6.14.2 Citizens actions and action groups, , 201, 201, 202, , 6.15 PUBLIC AWARENESS, 6.15.1 Using an Environmental Calendar of Activities, 6.15.2 What can I do?, , 204, 204, 205, , UNIT 7: HUMAN POPULATION AND THE ENVIRONMENT, 7.1 POPULATION GROWTH, VARIATION AMONG NATIONS, 7.1.1 Global population growth, , 214, 214, , 7.2 POPULATION EXPLOSION – FAMILY WELFARE PROGRAM, 7.2.1 Methods of sterilization, 7.1.2 Urbanization, , 215, 217, 217, , 7.3 ENVIRONMENTAL AND HUMAN HEALTH, 7.3.1 Environmental health, 7.3.2 Climate and health, 7.3.3 Infectious diseases, 7.3.4 Water-related diseases, 7.3.5 Risks due to chemicals in food, 7.3.6 Cancer and environment, , 220, 221, 223, 224, 227, 231, 232, , 7.4 HUMAN RIGHTS, 7.4.1 Equity, 7.4.2 Nutrition, health and human rights, 7.4.3 Intellectual Property Rights and Community Biodiversity Registers, , 233, 233, 234, 235, , 7.5 VALUE EDUCATION, 7.5.1 Environmental Values, 7.5.2 Valuing Nature, 7.5.3 Valuing cultures, 7.5.4 Social justice, 7.5.5 Human heritage, 7.5.6 Equitable use of Resources, 7.5.7 Common Property Resources, 7.5.8 Ecological degradation, , 236, 237, 240, 241, 241, 242, 242, 242, 242, , 7.6 HIV/AIDS, , 243, , Natural Resources, , Preliminary Pages.p65, , xi, , 11, , 4/9/2004, 5:06 PM
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7.7 WOMEN AND CHILD WELFARE, , 244, , 7.8 ROLE OF INFORMATION TECHNOLOGY IN ENVIRONMENT AND HUMAN HEALTH 247, , UNIT 8: FIELD WORK, 8.1 VISIT TO A LOCAL AREA TO DOCUMENT ENVIRONMENTAL ASSETS,, RIVER/FOREST/GRASSLANDS/HILL/MOUNTAIN, , 250, , 8.2 VISIT TO A LOCAL POLLUTED SITE, , 262, , 8.3 STUDY OF COMMON PLANTS, INSECTS, BIRDS, , 268, , 8.4 STUDY OF SIMPLE ECOSYSTEMS, , 270, , Environmental Studies for Undergraduate Courses, , xii, , Preliminary Pages.p65, , 12, , 4/9/2004, 5:06 PM
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Preface, Perhaps no other country has moved so rapidly from a position of complacency in creating environmental awareness into infusing these newer pro environmental concepts into formal curricular, processes as has happened in India over the last few years. This has undoubtedly been accelerated, by the judgement of the Honorable Supreme Court of India that Environmental Education must, form a compulsory core issue at every stage in our education processes., For one who has fought to implement a variety of environment education programs for schools and, colleges and for the public at large, this is indeed a welcome change. The author is currently constantly asked to provide inputs to ‘environmentalise’ textbooks and provide inputs at NCERT, SCERTs, and at the UGC level to further the cause of formal environment education., This textbook has been rapidly produced as an outcome of a UGC Committee that included the, author and was set up to develop a common core module syllabus for environmental studies at the, undergraduate level, to be used by every University in the country. This rush job invites comments, from just about everyone who wishes to contribute towards its improvement in the coming years., Environment Education can never remain static. It must change with the changing times which, inevitably changes our environment., Each of us creates waves around us in our environment that spread outwards like the ripples generated by dropping a stone in a quiet pond. Every one of us is constantly doing something to our, environment and it is frequently a result of an act that we can hardly ever reverse. Just as once the, stone has hit the water one cannot stop the ripple effect from disturbing the pond., This textbook is written to bring about an awareness of a variety of environmental concerns. It, attempts to create a pro-environmental attitude and a behavioral pattern in society that is based on, creating sustainable lifestyles. But a textbook can hardly be expected to achieve a total behavioral, change in society. Conservation is best brought about through creating a love for nature. If every, college student is exposed to the wonders of the Indian wilderness, a new ethic towards conservation will emerge., Erach Bharucha,, Pune, 2004., , Natural Resources, , Preliminary Pages.p65, , xiii, , 13, , 4/9/2004, 5:06 PM
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Environmental Studies for Undergraduate Courses, , xiv, , Preliminary Pages.p65, , 14, , 4/9/2004, 5:06 PM
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Foreword, , Natural Resources, , Preliminary Pages.p65, , xv, , 15, , 4/9/2004, 5:06 PM
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Acknowledgements, I would like at the very outset to thank the residual wilderness of our country that has, since my, childhood, excited in my consciousness a desire to protect nature. For me the wilderness is a throbbing, living place – the home of the goddess of nature, which is none other than Mother Earth. One, can only bow to her and apologize for what humankind has done during a short span of time., This textbook came about from my having been included in a Committee selected by the UGC to, develop a practical and ‘do-able’ syllabus as a Core Module for Environmental Studies for all undergraduate courses. The Committee met several times and had enthusiastic rounds of discussion as to, what should be included and what was unsuitable for a unique course of this nature. While hoping, only to sensitize young people to our environment, it has also to be as comprehensive as feasible., I wish to thank Prof. C Manoharachary, Prof. S Thayumanavan, Prof. DC Goswami, Shri R Mehta, and Dr. NK Jain, who were the esteemed members of this Committee. All the inputs the Committee made during these deliberations have found a place in the current textbook. I thus take pleasure in thanking the Committee Members for their wholehearted participatory role in evolving the, curriculum, which I have tried to translate into a textbook to uphold the spirit in which the curriculum was framed., I have no words to thank the Chairman of the UGC, Dr. Arun Nighvekar, who has whole heartedly, supported the Committee and gave freely of his valuable time to deliberate the nature of the, course. He has always been as inspiration for me. Dr. (Mrs.) HK Chauhan began co-ordinating the, work of the Committee during the early part of its tenure. This was further carried out due to the, enthusiasm and constant support of Dr. NK Jain, Joint Secretary of the UGC. I cannot thank them, enough for their cooperation and many kind gestures., All my faculty at the BVIEER have helped in producing this output. Shamita Kumar wrote the chapter on pollution, which she has painstakingly developed to suit the needs of undergraduate students from different faculties. Her expertise as a highly innovative teacher in environment has given, her the background that is necessary to draft a suitable Unit for this book. Shambhavi Joshi helped, me to frame the final chapter on fieldwork. Prasanna Kolte and Jaya Rai did all the work to develop, a CD ROM based on the text to make a more presentable version of the book. Prasanna also dug up, several case studies included in the book. I must thank our artists Sushma Durve and Anagha, Deshpande who have painstakingly made a large number of drawings. Without them the textbook, would have been yet another drab textbook. One person who has done an excellent job of editing, the English, rearranging bits of the book and removing redundant material is Chinmaya Dunster, a, musician by profession, an editor by calling and an environmentalist at heart. He has spent many, painful hours going over the text with a fine tooth English comb. I cannot thank him enough for his, enormous contribution towards the completion of this book. Finally, for the one person who has, put all her heart and soul into this book, working long hours, and cheerfully making the constant, changes I demanded. I have no words to thank Ms. Behafrid Patel. She has been the patient, all, round support system in this complex task. Without her it could not have been produced in this, brief span of time., Environmental Studies for Undergraduate Courses, , xvi, , Preliminary Pages.p65, , 16, , 4/9/2004, 5:06 PM
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UNIT 1:, , The Multidisciplinary Nature of, Environmental Studies, , 1.1, , 1.2, , DEFINITION, SCOPE AND IMPORTANCE, , 3, , 1.1.1, , Definition, , 3, , 1.1.2, , Scope, , 3, , 1.1.3, , Importance, , 5, , NEED FOR PUBLIC AWARENESS, , 8, , 1.2.1, , Institutions in Environment, , 9, , 1.2.2, , People in Environment, , 12, , This course on the environment is unlike any other. It is not only a collection, of facts or information about the environment. It is about the way we all, should live. It is expected to give you information about the environment, that will lead to a concern for your own environment. When you develop, this concern, you will begin to act at your own level to protect the, environment we all live in. This is the objective of the course and the, syllabus is a framework on which we must all realign our lives., , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 1, , 1, , 4/9/2004, 5:07 PM
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This textbook deals with major environmental concerns that have been, identified as important areas where background information is essential for a, better understanding of our environment. It stresses on a balanced view of, issues that affect our daily lives. These issues are related to the conflict between, existing ‘development’ strategies and the need for ‘environmental, conservation’. Unlike most other textbooks, it not only makes the reader better, informed on these concerns, but is expected to lead him or her towards positive, action to improve the environment., There are three reasons for studying the state of the environment. Firstly is the, need for information that clarifies modern environmental concepts such as, the need to conserve biodiversity, the need to lead more sustainable lifestyles, and the need to use resources more equitably. Secondly, there is a need to, change the way in which we view our own environment by a practical approach, based on observation and self learning. Thirdly there is the need to create a, concern for our environment that will trigger pro-environmental action,, including activities we can do in our daily life to protect it., , Environmental Studies for Undergraduate Courses, , 2, , Chapter1.p65, , 2, , 4/9/2004, 5:07 PM
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1.1 DEFINITION, SCOPE AND IMPORTANCE, 1.1.1 Definition, Environmental studies deals with every issue that, affects an organism. It is essentially a, multidisciplinary approach that brings about an, appreciation of our natural world and human, impacts on its integrity. It is an applied science, as its seeks practical answers to making human, civilization sustainable on the earth’s finite resources., Its components include biology, geology, chemistry, physics, engineering, sociology, health,, anthropology, economics, statistics, computers, and philosophy., , 1.1.2 Scope, As we look around at the area in which we live,, we see that our surroundings were originally a, natural landscape such as a forest, a river, a, mountain, a desert, or a combination of these, elements. Most of us live in landscapes that have, been heavily modified by human beings, in villages, towns or cities. But even those of us who, live in cities get our food supply from surrounding villages and these in turn are dependent on, natural landscapes such as forests, grasslands,, rivers, seashores, for resources such as water, for agriculture, fuel wood, fodder, and fish. Thus, our daily lives are linked with our surroundings, and inevitably affects them. We use water to, drink and for other day-to-day activities. We, breathe air, we use resources from which food, is made and we depend on the community of, living plants and animals which form a web of, life, of which we are also a part. Everything, around us forms our environment and our lives, depend on keeping its vital systems as intact as, possible., Our dependence on nature is so great that we, cannot continue to live without protecting the, , earth’s environmental resources. Thus most traditions refer to our environment as ‘Mother, Nature’ and most traditional societies have, learned that respecting nature is vital for their, livelihoods. This has led to many cultural practices that helped traditional societies protect and, preserve their natural resources. Respect for, nature and all living creatures is not new to India. All our traditions are based on these values., Emperor Ashoka’s edict proclaimed that all, forms of life are important for our well being in, Fourth Century BC., Over the past 200 years however, modern societies began to believe that easy answers to the, question of producing more resources could be, provided by means of technological innovations., For example, though growing more food by, using fertilizers and pesticides, developing better strains of domestic animals and crops, irrigating farmland through mega dams and, developing industry, led to rapid economic, growth, the ill effects of this type of development, led to environmental degradation., The industrial development and intensive agriculture that provides the goods for our increasingly consumer oriented society uses up large, amounts of natural resources such as water,, minerals, petroleum products, wood, etc. Nonrenewable resources, such as minerals and oil, are those which will be exhausted in the future, if we continue to extract these without a, thought for subsequent generations. Renew-, , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 3, , 3, , 4/9/2004, 5:07 PM
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able resources, such as timber and water, are, those which can be used but can be regenerated by natural processes such as regrowth or, rainfall. But these too will be depleted if we continue to use them faster than nature can replace them. For example, if the removal of, timber and firewood from a forest is faster than, the regrowth and regeneration of trees, it cannot replenish the supply. And loss of forest cover, not only depletes the forest of its resources, such, as timber and other non-wood products, but, affect our water resources because an intact, natural forest acts like a sponge which holds, water and releases it slowly. Deforestation leads, to floods in the monsoon and dry rivers once, the rains are over., Such multiple effects on the environment resulting from routine human activities must be, appreciated by each one of us, if it is to provide, us with the resources we need in the long-term., Our natural resources can be compared with, money in a bank. If we use it rapidly, the capital, will be reduced to zero. On the other hand, if, we use only the interest, it can sustain us over, the longer term. This is called sustainable, utilisation or development., , Activity 1:, Take any article that you use in daily life –, a bucket full of water, or an item of food, a, table, or a book. Trace its components journey backwards from your home to their origins as natural resources in our, environment. How many of these components are renewable resources and how, many non-renewable?, Understanding and making ourselves more, aware of our environmental assets and problems is not enough. We, each one of us, must, become increasingly concerned about our envi-, , •, , What is the rarity of the resource and where, does it originate?, , •, , Who uses it most intensively and how?, , •, , How is it being overused or misused?, , •, , Who is responsible for its improper use –, the resource collector, the middleman, the, end user?, , •, , How can we help to conserve it and prevent its unsustainable use?, , Activity 2:, Try to answer the questions above for one, of the components in the article you chose, in Activity 1. Then answer the following, questions:, , Environmental Studies for Undergraduate Courses, , 4, , Chapter1.p65, , ronment and change the way in which we use, every resource. Unsustainable utilization can, result from overuse of resources, because of, population increase, and because many of us, are using more resources than we really need., Most of us indulge in wasteful behaviour patterns without ever thinking about their environmental impacts. Thus, for all our actions to be, environmentally positive we need to look from, a new perspective at how we use resources. For, every resource we use we must ask ourselves, the following questions:, , 4, , 4/9/2004, 5:07 PM
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•, , Are you using, unsustainably?, , that, , resource, , •, , In what ways could you reduce, reuse, and recycle that resource?, , •, , Is there an unequal distribution of this, resource so that you are more fortunate, than many others who have less access, to it?, , each of us uses also increases, the earth’s resource base must inevitably shrink. The earth, cannot be expected to sustain this expanding, level of utilization of resources. Added to this is, misuse of resources. We waste or pollute large, amounts of nature’s clean water; we create, more and more material like plastic that we discard after a single use; and we waste colossal, amounts of food, which is discarded as garbage., Manufacturing processes create solid waste, byproducts that are discarded, as well as chemicals that flow out as liquid waste and pollute, water, and gases that pollute the air. Increasing, amounts of waste cannot be managed by natural processes. These accumulate in our environment, leading to a variety of diseases and other, adverse environmental impacts now seriously affecting all our lives. Air pollution leads to respiratory diseases, water pollution to, gastro-intestinal diseases, and many pollutants, are known to cause cancer., , Once we begin to ask these questions of ourselves, we will begin to live lifestyles that are, more sustainable and will support our environment., , 1.1.3 Importance, Environment is not a single subject. It is an integration of several subjects that include both, Science and Social Studies. To understand all, the different aspects of our environment we, need to understand biology, chemistry, physics,, geography, resource management, economics, and population issues. Thus the scope of environmental studies is extremely wide and covers, some aspects of nearly every major discipline., We live in a world in which natural resources, are limited. Water, air, soil, minerals, oil, the, products we get from forests, grasslands, oceans, and from agriculture and livestock, are all a part, of our life support systems. Without them, life, itself would be impossible. As we keep increasing in numbers and the quantity of resources, , Improving this situation will only happen if each, of us begins to take actions in our daily lives, that will help preserve our environmental resources. We cannot expect Governments alone, to manage the safeguarding of the environment,, nor can we expect other people to prevent, environmental damage. We need to do it ourselves. It is a responsibility that each of us must, take on as ones own., , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 5, , 5, , 4/9/2004, 5:07 PM
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Activity 3:, •, , What happens to it when you throw it away/, where does it go?, , Think of all the things that you do in a, day. List these activities and identify the, main resources used during these activities. What can you do to prevent, waste, reuse articles that you normally, throw away, what recycled materials, can you use?, , Example – Fossil fuels:, How much do you use? Can you reduce your, consumption?, What effect does it have on the air we breathe?, , •, , Think of the various energy sources you, use everyday. How could you reduce, their use?, , Activity 4: Exercises in self learning about, the environment, Attempt to assess the level of damage to, the environment due to your actions that, have occurred during your last working day,, the last week, the last year. Then estimate, the damage you are likely to do in your lifetime if you continue in your present ways., Use the following examples for the above exercise:, , Example – Plastic: Plastic bags, plastic ball pens, Think about all the articles you use daily that, are made from plastic. Plastic plays an important part in our modern lives., , When we leave a motorbike or car running during a traffic stop, we do not usually remember, that the fuel we are wasting is a part of a nonrenewable resource that the earth cannot reform. Once all the fossil fuels are burnt off, it, will mean the end of oil as a source of energy., Only if each of us contributes our part in conserving fossil based energy can we make it last, longer on earth., , Example – Water:, How much do you really need to use, as against, how much you waste when you:, (a) Brush your teeth? (b) Have a bath? (c) Wash, clothes? (d) Wash the scooter or car?, Where did the water come from? What is its, actual source? How has it reached you?, Where will the waste water go?, , Make a list of the plastic articles you usually use., How can you reduce the amount of plastic you, use?, , Do you feel you should change the way you use, water? How can you change this so that it is, more sustainable?, , What effects does plastic have on our environment?, , Example – Food:, , Where did the plastic come from/ how is it, made?, , Environmental Studies for Undergraduate Courses, , 6, , Chapter1.p65, , Where has it come from? How is it grown? What, chemicals are used in its production? How does, it reach you?, , 6, , 4/9/2004, 5:07 PM
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How is it cooked?, How much is wasted? How is the waste disposed off?, , Example – Paper:, What is it made from?, Where does it come from and what happens, during manufacture?, How much do you use and how much do you, waste? How can you prevent it from being, wasted?, , Example – Electrical Energy:, , struction of a forest, wetland or other natural, area and do not protest about it, future generations are being denied the use of these valuable resources and will blame us for these rash, and negligent actions towards the environment., Thus the urgent need to protect all living species is a concept that we need to understand, and act upon. While individually, we perhaps, cannot directly prevent the extinction of a species, creating a strong public opinion to protect, the National Parks and Wildlife Sanctuaries in, which wild species live is an importance aspect, of sustainable living. There is a close link between agriculture and the forest, which illustrates its productive value. For crops to be, successful, the flowers of fruit trees and vegetables must be pollinated by insects, bats and, birds. Their life cycles however frequently require, intact forests., , How much do you use everyday? Where does it, come from?, How do you waste it? How can you conserve, energy?, , Productive value of nature: As scientists make, new advances in fields such as biotechnology, we begin to understand that the world’s species contain an incredible and uncountable number of complex chemicals. These are the raw, materials that are used for developing new, medicines and industrial products and are a, storehouse from which to develop thousands, of new products in the future. The flowering, plants and insects that form the most speciesrich groups of living organisms are thus vital for, the future development of man. If we degrade, their habitat these species will become extinct., If one sees being sold or used, a product that, comes from an illegally killed wild species, if we, do not inform the authorities, we become party, to its extinction. Once they are lost, man cannot bring them back. When we permit the de-, , Aesthetic/Recreational value of nature: The, aesthetic and recreational values that nature, possesses enlivens our existence on earth. This, is created by developing National Parks and, Wildlife Sanctuaries in relatively undisturbed, areas. A true wilderness experience has not only, recreational value but is an incredible learning, experience. It brings about an understanding of, the oneness of nature and the fact that we are, entirely dependent upon the intricate functioning of ecosystems., The beauty of nature encompasses every aspect, of the living and non-living part of our earth., One can appreciate the magnificence of a mountain, the power of the sea, the beauty of a forest, and the vast expanse of the desert. It is these, natural vistas and their incredible diversity of, plant and animal life that has led to the development of several philosophies of life. It has also, inspired artists to develop visual arts and writers and poets to create their works that vitalize, our lives., , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 7, , 7, , 4/9/2004, 5:07 PM
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A wilderness experience has exceptional recreational value. This has been described as nature, tourism, or wildlife tourism, and is also one aspect of adventure tourism. These recreational, facilities not only provide a pleasurable experience but are intended to create a deep respect, and love for nature. They are also key tools in, educating people about the fragility of the environment and the need for sustainable lifestyles., In an urban setting, green spaces and gardens, are vital to the pschycological and physical health, of city dwellers. It provides not only an aesthetic, and visual appeal but the ability to ensure that, each individual is able to access a certain amount, of peace and tranquility. Thus urban environmental planners must ensure that these facilities are created in growing urban complexes., Another important conservation education facility in urban settings includes the need to set, up well designed and properly managed zoological parks and aquariums. These have got, great value in sensitizing school students to wildlife. Many young people who frequented zoos, as young children grow up to love wildlife and, become conservationists., In the absence of access to a Protected Area, a, botanical garden or a zoo, one concept that can, be developed is to create small nature awareness areas with interpretation facilities at district and taluka levels. These areas can be, developed to mimic natural ecosystems even, though they could be relatively small in size. Such, nature trails are invaluable assets for creating, conservation education and awareness. They can, , be developed in a small woodlot, a patch of, grassland, a pond ecosystem, or be situated, along an undisturbed river or coastal area. This, would bring home to the visitor the importance, of protecting our dwindling wilderness areas., , The option values of nature: While we utilise, several goods and services of nature and enjoy, its benefits, we, must recognize, that every activity, that we do in our, daily lives has an, adverse impact, on nature’s integrity. Thus if we use up all our resources, kill off, and let species of plants and animals become, extinct on earth, pollute our air and water, degrade land, and create enormous quantities of, waste, we as a generation will leave nothing, for future generations. Our present generation, has developed its economies and lifestyles on, unsustainable patterns of life. however, nature, provides us with various options on how we, utilize its goods and services. This is its option, value. We can use up goods and services greedily, and destroy its integrity and long term values,, or we can use its resources sustainably and reduce our impacts on the environment. The option value allows us to use its resources, sustainably and preserve its goods and services, for the future., , 1.2 NEED FOR PUBLIC AWARENESS, As the earth’s natural resources are, dwindling and our environment is, being increasingly degraded by, human activities, it is evident that, something needs to be done. We, often feel that managing all this is, something that the Government, should do. But if we go on endangering our environment, there is no, Environmental Studies for Undergraduate Courses, , 8, , Chapter1.p65, , 8, , 4/9/2004, 5:07 PM
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way in which the Government can perform all, these clean-up functions. It is the prevention of, environment degradation in which we must all, take part that must become a part of all our, lives. Just as for any disease, prevention is better than cure. To prevent ill-effects on our environment by our actions, is economically more, viable than cleaning up the environment once, it is damaged. Individually we can play a major, role in environment management. We can reduce wasting natural resources and we can act, as watchdogs that inform the Government, about sources that lead to pollution and degradation of our environment., This can only be made possible through mass, public awareness. Mass media such as newspapers, radio, television, strongly influence public, opinion. However, someone has to bring this, about. If each of us feels strongly about the, environment, the press and media will add to, our efforts. Politicians in a democracy always, respond positively to a strong publicly supported, movement. Thus if you join an NGO that supports conservation, politicians will make green, policies. We are living on spaceship earth with a, limited supply of resources. Each of us is responsible for spreading this message to as many, people as possible., Suggested further activities for concerned students:, •, , Join a group to study nature, such as WWFI or BNHS, or another environmental group., , •, , Begin reading newspaper articles and periodicals such as ‘Down to Earth’, WWF-I, newsletter, BNHS Hornbill, Sanctuary magazine, etc. that will tell you more about our, environment. There are also several environmental websites., , •, , Lobby for conserving resources by taking, up the cause of environmental issues during discussions with friends and relatives., , Practice and promote issues such as saving, paper, saving water, reducing use of plastics, practicing the 3Rs principle of reduce,, reuse, recycle, and proper waste disposal., •, , Join local movements that support activities such as saving trees in your area, go on, nature treks, recycle waste, buy environmentally friendly products., , •, , Practice and promote good civic sense such, as no spitting or tobacco chewing, no, throwing garbage on the road, no smoking, in public places, no urinating or defecating, in public places., , •, , Take part in events organised on World, Environment Day, Wildlife Week, etc., , •, , Visit a National Park or Sanctuary, or spend, time in whatever nature you have near your, home., , 1.2.1 Institutions in Environment, There have been several Government and Nongovernment organizations that have led to environmental protection in our country. They have, led to a growing interest in environmental protection and conservation of nature and natural, resources. The traditional conservation practices, that were part of ancient India’s culture have, however gradually disappeared. Public awareness is thus a critical need to further environmental protection. Among the large number of, institutions that deal with environmental protection and conservation, a few well-known, organizations include government organisations, such as the BSI and ZSI, and NGOs such as BNHS,, WWF-I, etc., , Bombay Natural History Society (BNHS),, Mumbai: the BNHS began as a small society of, six members in 1883. It grew from a group of, , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 9, , 9, , 4/9/2004, 5:07 PM
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shikaris and people from all walks of life into a, major research organisation that substantially, influenced conservation policy in the country., The influence on wildlife policy building, research, popular publications and peoples, action have been unique features of the multifaceted society. Undoubtedly its major contribution has been in the field of wildlife research., It is India’s oldest conservation research based, NGO and one that has acted at the forefront of, the battle for species and ecosystems. The BNHS, publishes a popular magazine called Hornbill and, also an internationally well-known Journal on, Natural History. Its other publications include the, Salim Ali Handbook on birds, JC Daniel’s book, of Indian Reptiles, SH Prater’s book of Indian, Mammals and PV Bole’s book of Indian Trees., One of its greatest scientists was Dr. Salim Ali, whose ornithological work on the birds of the, Indian subcontinent is world famous. The BNHS, has over the years helped Government to frame, wildlife related laws and has taken up battles, such as the ‘Save the Silent Valley’ campaign., , World Wide Fund for Nature (WWF-I), New, Delhi: The WWF-I was initiated in 1969 in, Mumbai after which the headquarters were, shifted to Delhi with several branch offices all, over India. The early years focused attention on, wildlife education and awareness. It runs several programs including the Nature Clubs of India program for school children and works as a, think tank and lobby force for environment and, development issues., , Center for Science and Environment (CSE),, New Delhi: Activities of this Center include, organising campaigns, holding workshops and, conferences, and producing environment related, publications. It published a major document on, the ‘State of India’s Environment’, the first of, its kind to be produced as a Citizen’s Report on, the Environment. The CSE also publishes a popular magazine, ‘Down to Earth’, which is a Sci-, , CPR Environmental Education Centre, Madras: The CPR EEC was set up in 1988. It conducts a variety of programs to spread, environmental awareness and creates an interest in conservation among the general public. It, focussed attention on NGOs, teachers, women,, youth and children to generally promote conservation of nature and natural resources. Its, programs include components on wildlife and, biodiversity issues. CPR EEC also produces a large, number of publications., , Centre for Environment Education (CEE),, Ahmedabad: The Centre for Environment Education, Ahmedabad was initiated in 1989. It has, a wide range of programs on the environment, and produces a variety of educational material., CEE’s Training in Environment Education {TEE}, program has trained many environment educators., , Bharati Vidyapeeth Institute of Environment Education and Research (BVIEER),, Pune: This is part of the Bharati Vidyapeeth, Deemed University. The Institute has a PhD, a, Masters and Bachelors program in Environmental Sciences. It also offers an innovative Diploma, in Environment Education for in-service teachers. It implements a large outreach programme, that has covered over 135 schools in which it, trains teachers and conducts fortnightly Environment Education Programs. Biodiversity Conservation is a major focus of its research, initiatives. It develops low cost Interpretation, Centres for Natural and Architectural sites that, are highly locale specific as well as a large, amount of innovative environment educational, Environmental Studies for Undergraduate Courses, , 10, , Chapter1.p65, , ence and Environment fortnightly. It is involved, in the publication of material in the form of, books, posters, video films and also conducts, workshops and seminars on biodiversity related, issues., , 10, , 4/9/2004, 5:07 PM
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material for a variety of target groups. Its unique, feature is that it conducts environment education from primary school level to the postgraduate level. The BVIEER has produced several EE, aids. It has developed a teacher’s handbook, linked to school curriculum, a textbook for UGC, for its undergraduate course on environment., Its Director has developed a CD ROM on India’s, biodiversity published by Mapin Publishers,, Ahmedabad., , Uttarkhand Seva Nidhi (UKSN), Almora: The, Organisation is a Nodal Agency which supports, NGOs in need of funds for their environment, related activities. Its major program is organising, and training school teachers to use its locale, specific Environment Education Workbook Program. The main targets are linked with sustainable resource use at the village level through, training school children. Its environment education program covers about 500 schools., , Kalpavriksh, Pune: This NGO, initially Delhi, based, is now working from Pune and is active, in several other parts of India. Kalpavriksh works, on a variety of fronts: education and awareness;, investigation and research; direct action and, lobbying; and litigation with regard to environment and development issues. Its activities include talks and audio-visuals in schools and, colleges, nature walks and outstation camps,, organising student participation in ongoing campaigns including street demonstrations, pushing for consumer awareness regarding organic, food, press statements, handling green alerts,, and meetings with the city’s administrators. It is, involved with the preparation of site-specific,, environmental manuals for schoolteachers., Kalpavriksh was responsible for developing, India’s National Biodiversity Strategy and Action, Plan in 2003., , Salim Ali Center for Ornithology and Natural History (SACON), Coimbatore: This institution was Dr. Salim Ali’s dream that became a, reality only after his demise. He wished to support a group of committed conservation scientists on a permanent basis. Initially conceived as, being a wing of the Bombay Natural History, Society (BNHS) it later evolved as an independent organisation based at Coimbatore in 1990., It has instituted a variety of field programs that, have added to the country’s information on our, threatened biodiversity., , Wildlife Institute of India (WII), Dehradun:, This Institution was established in 1982, as a, major training establishment for Forest Officials, and Research in Wildlife Management. Its most, significant publication has been ‘Planning A, Wildlife Protected Area Network for India’, (Rodgers and Panwar, 1988). The organisation, has over the years added an enormous amount, of information on India’s biological wealth. It, has trained a large number of Forest Department Officials and Staff as Wildlife Managers., Its M.Sc. Program has trained excellent wildlife, scientists. It also has an Environment Impact, Assessment (EIA) cell. It trains personnel in, ecodevelopment, wildlife biology, habitat management and Nature interpretation., , Botanical Survey of India (BSI): The Botanical Survey of India (BSI) was established in 1890, at the Royal Botanic Gardens, Calcutta. However it closed down for several years after 1939, and was reopened in 1954. In 1952 plans were, made to reorganise the BSI and formulate its, objectives. By 1955 the BSI had its headquarters in Calcutta with Circle Offices at, Coimbatore, Shillong, Pune and Dehra Dun., Between 1962 and 1979, offices were established in Allahbad, Jodhpur, Port Blair, Itanagar, and Gangtok. The BSI currently has nine regional, centres. It carries out surveys of plant resources, in different regions., , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 11, , 11, , 4/9/2004, 5:07 PM
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Zoological Survey of India (ZSI): The ZSI was, established in1916. Its mandate was to do a, systematic survey of fauna in India. It has over, the years collected ‘type specimens’ on the bases, of which our animal life has been studied over, the years. Its origins were collections based at, the Indian Museum at Calcutta, which was established in 1875. Older collections of the Asiatic Society of Bengal, which were made, between 1814 and 1875, as well as those of, the Indian Museum made between 1875 and, 1916 were then transferred to the ZSI. Today it, has over a million specimens! This makes it one, of the largest collections in Asia. It has done an, enormous amount of work on taxonomy and, ecology. It currently operates from 16 regional, centers., , in the US in the 1920s. He designed the early, policies on wilderness conservation and wildlife, management. In the 1960s Rachel Carson published several articles that caused immediate, worldwide concern on the effects of pesticides, on nature and mankind. She wrote a wellknown book called ‘Silent Spring’ which eventually led to a change in Government policy and, public awareness. EO Wilson is an entomologist who envisioned that biological diversity was, a key to human survival on earth. He wrote ‘Diversity of Life’ in 1993, which was awarded a, prize for the best book published on environmental issues. His writings brought home to the, world the risks to mankind due to man made, disturbances in natural ecosystems that are leading to the rapid extinction of species at the global level., , 1.2.2 People in Environment, , There have been a number of individuals who, have been instrumental in shaping the environmental history in our country. Some of the wellknown names in the last century include, environmentalists, scientists, administrators, legal experts, educationists and journalists. Salim, Ali’s name is synonymous with ornithology in, India and with the Bombay Natural History Society (BNHS). He also wrote several great books, including the famous ‘Book of Indian Birds’. His, autobiography, ‘Fall of a Sparrow’ should be, read by every nature enthusiast. He was our, country’s leading conservation scientist and influenced environmental policies in our country, for over 50 years. Indira Gandhi as PM has, played a highly significant role in the preservation of India’s wildlife. It was during her period, as PM, that the network of PAs grew from 65, to 298! The Wildlife Protection Act was formulated during the period when she was PM and, the Indian Board for Wildlife was extremely active as she personally chaired all its meetings., India gained a name for itself by being a major, player in CITES and other International Environmental Treaties and Accords during her tenure., BNHS frequently used her good will to get conservation action initiated by the Government., , There are several internationally known environmental thinkers. Among those who have made, landmarks, the names that are usually mentioned are Charles Darwin, Ralph Emerson,, Henry Thoreau, John Muir, Aldo Leopald, Rachel, Carson and EO Wilson. Each of these thinkers, looked at the environment from a completely, different perspective. Charles Darwin wrote, the ‘Origin of Species’, which brought to light, the close relationship between habitats and species. It brought about a new thinking of man’s, relationship with other species that was based, on evolution. Alfred Wallace came to the same, conclusions during his work. Ralph Emerson, spoke of the dangers of commerce to our environment way back in the 1840s. Henry, Thoreau in the 1860s wrote that the wilderness should be preserved after he lived in the, wild for a year. He felt that most people did not, care for nature and would sell it off for a small, sum of money. John Muir is remembered as, having saved the great ancient sequoia trees in, California’a forests. In the 1890s he formed the, Sierra club, which is a major conservation NGO, in the USA. Aldo Leopald was a forest official, , Environmental Studies for Undergraduate Courses, , 12, , Chapter1.p65, , 12, , 4/9/2004, 5:07 PM
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S P Godrej was one of India’s greatest supporters of wildlife conservation and nature awareness programs. Between 1975 and 1999, SP, Godrej received 10 awards for his conservation, activities. He was awarded the Padma Bhushan, in 1999. His friendship with people in power, combined with his deep commitment for conservation led to his playing a major advocacy, role for wildlife in India. M S Swaminathan is, one of India’s foremost agricultural scientists and, has also been concerned with various aspects, of biodiversity conservation both of cultivars and, wild biodiversity. He has founded the MS, Swaminathan Research Foundation in Chennai,, which does work on the conservation of biological diversity. Madhav Gadgil is a wellknown ecologist in India. His interests range, from broad ecological issues such as developing Community Biodiversity Registers and conserving sacred groves to studies on the behaviour, of mammals, birds and insects. He has written, several articles, published papers in journals and, is the author of 6 books. M C Mehta is undoubtedly India’s most famous environmental, lawyer. Since 1984, he has filed several Public, Interest Litigations for supporting the cause of, environmental conservation. His most famous, and long drawn battles supported by the Supreme Court include protecting the Taj Mahal,, cleaning up the Ganges River, banning intensive shrimp farming on the coast, initiating Government to implement environmental education, in schools and colleges, and a variety of other, conservation issues. Anil Agarwal was a journalist who wrote the first report on the ‘State, of India’s Environment’ in 1982. He founded the, Center for Science and Environment which is, an active NGO that supports various environmental issues. Medha Patkar is known as one, of India’s champions who has supported the, cause of downtrodden tribal people whose environment is being affected by the dams on the, Narmada river. Sunderlal Bahugna’s Chipko, Movement has become an internationally wellknown example of a highly successful conservation action program through the efforts of, , local people for guarding their forest resources., His fight to prevent the construction of the Tehri, Dam in a fragile earthquake prone setting is a, battle that he continues to wage. The Garhwal, Hills will always remember his dedication to the, cause for which he has walked over 20 thousand kilometers., , The Multidisciplinary Nature of Environmental Studies, , Chapter1.p65, , 13, , 13, , 4/9/2004, 5:07 PM
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UNIT 2:, , Natural Resources, , Chapter2.p65, , 2.1 INTRODUCTION, , 16, , 2.2 RENEWABLE AND NON-RENEWABLE RESOURCES, , 20, , 2.2.1 Natural resources and associated problems, , 20, , 2.2.2 Non-renewable resources, , 22, , 2.2.3 Renewable resources, , 22, , a. Forest Resources: Use and over-exploitation, deforestation, case studies., Timber extraction, mining, dams and their effects on forests and tribal people, , 23, , b. Water Resources: Use and over-utilisation of surface and ground water,, floods, drought, conflicts over water, dams – benefits and problems., , 26, , c., , 30, , Mineral Resources: Use and exploitation, environmental effects of extracting, and using mineral resources, case studies., , d. Food Resources: World food problems, Changes in landuse by agriculture and, grazing, Effects of modern agriculture, Fertilizer/ pesticide problems,, Water logging and salinity, , 32, , e. Energy Resources: Increasing energy needs, Renewable/ non renewable,, Use of Alternate energy sources, Case studies, , 35, , f., , 48, , Land resources: Land as a resource, land degradation, man-induced land-slides,, soil erosion and desertification., , 2.3 ROLE OF AN INDIVIDUAL IN CONSERVATION OF NATURAL RESOURCES, , 50, , 2.4 EQUITABLE USE OF RESOURCES FOR SUSTAINABLE LIFESTYLES, , 51, , Natural Resources, , 15, , 15, , 4/9/2004, 5:07 PM
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2.1 INTRODUCTION, Our environment provides us with a variety of, goods and services necessary for our day to day, lives. These natural resources include, air, water, soil, minerals, along with the climate and, solar energy, which form the non-living or ‘abiotic’ part of nature. The ‘biotic’ or living parts, of nature consists of plants and animals, including microbes. Plants and animals can only survive as communities of different organisms, all, closely linked to each in their own habitat, and, requiring specific abiotic conditions. Thus, forests, grasslands, deserts, mountains, rivers, lakes, and the marine environment all form habitats, for specialised communities of plants and animals to live in. Interactions between the abiotic, aspects of nature and specific living organisms, together form ecosystems of various types., Many of these living organisms are used as our, food resources. Others are linked to our food, less directly, such as pollinators and dispersers, of plants, soil animals like worms, which recycle, nutrients for plant growth, and fungi and termites that break up dead plant material so that, micro-organisms can act on the detritus to reform soil nutrients., , History of our global environment: About, ten thousand years ago, when mankind changed, from a hunter-gatherer, living in wilderness areas such as forests and grasslands, into an agriculturalist and pastoralist, we began to change, the environment to suit our own requirements., As our ability to grow food and use domestic, animals grew, these ‘natural’ ecosystems were, developed into agricultural land. Most traditional, agriculturists depended extensively on rain,, streams and rivers for water. Later they began, to use wells to tap underground water sources, and to impound water and created irrigated land, by building dams. Recently we began to use fertilizers and pesticides to further boost the production of food from the same amount of land., However we now realize that all this has led to, several undesirable changes in our environment., Mankind has been overusing and depleting, natural resources. The over-intensive use of land, has been found to exhaust the capability of the, ecosystem to support the growing demands of, more and more people, all requiring more intensive use of resources. Industrial growth,, urbanisation, population growth and the enormous increase in the use of consumer goods,, have all put further stresses on the environment., They create great quantities of solid waste. Pollution of air, water and soil have begun to seriously affect human health., , Changes in land and resource use:, During the last 100 years, a better, health care delivery system and an, improved nutritional status has led to, rapid population growth,, especially in the developing countries. This phenomenal rise in human, numbers has, in the recent, past, placed great demands on the earth’s natural resources. Large, stretches of land such as forests, grasslands and, wetlands have been converted into intensive agriculture. Land has been taken for industry and, Environmental Studies for Undergraduate Courses, , 16, , Chapter2.p65, , 16, , 4/9/2004, 5:07 PM
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the urban sectors. These changes have brought, about dramatic alterations in land-use patterns, and rapid disappearance of valuable natural ecosystems. The need for more water, more food,, more energy, more consumer goods, is not only, the result of a greater population, but also the, result of over-utilization of resources by people, from the more affluent societies, and the affluent sections of our own., , Earth’s Resources and Man: The resources on, which mankind is dependent are provided by, various sources or ‘spheres’., , Industrial development is aimed at meeting, growing demands for all consumer items. However, these consumer goods also generate waste, in ever larger quantities. The growth of industrial complexes has led to a shift of people from, their traditional, sustainable, rural way of life to, urban centers that developed around industry., During the last few decades, several small urban centers have become large cities, some have, even become giant mega-cities. This has increased the disparity between what the surrounding land can produce and what the large, number of increasingly consumer-oriented, people in these areas of high population density consume. Urban centers cannot exist without resources such as water from rivers and, lakes, food from agricultural areas, domestic, animals from pasture lands and timber, fuel, wood, construction material and other resources, from forests. Rural agricultural systems are dependent on forests, wetlands, grasslands, rivers, and lakes. The result is a movement of natural, resources from the wilderness ecosystems and, agricultural sector to the urban user. The magnitude of the shift of resources has been increasing in parallel with the growth of industry and, urbanisation, and has changed natural landscapes all over the world. In many cases, this, has led to the rapid development of the urban, economy, but to a far slower economic development for rural people and serious impoverishment of the lives of wilderness dwellers. The, result is a serious inequality in the distribution, of resources among human beings, which is both, unfair and unsustainable., , 1) Atmosphere, •, , Oxygen for human respiration (metabolic requirements)., , •, , Oxygen for wild fauna in natural ecosystems, and domestic animals used by man as food., , •, , Oxygen as a part of carbon dioxide, used, for the growth of plants (in turn are used, by man)., , The atmosphere forms a protective shell over, the earth. The lowest layer, the troposphere,, the only part warm enough for us to survive in,, is only 12 kilometers thick. The stratosphere is, 50 kilometers thick and contains a layer of, sulphates which is important for the formation, of rain. It also contains a layer of ozone, which, absorbs ultra-violet light known to cause cancer and without which, no life could exist on, earth. The atmosphere is not uniformly warmed, by the sun. This leads to air flows and variations, in climate, temperature and rainfall in different, parts of the earth. It is a complex dynamic system. If its nature is disrupted it affects all mankind. Most air pollutants have both global and, regional effects., Living creatures cannot survive without air even, for a span of a few minutes. To continue to support life, air must be kept clean. Major pollutants of air are created by industrial units that, release various gases such as carbon dioxide,, carbon monoxide and toxic fumes into the air., Air is also polluted by burning fossil fuels. The, buildup of carbon dioxide which is known as, ‘greenhouse effect’ in the atmosphere is leading to current global warming. The growing, number of scooters, motorcycles, cars, buses and, trucks which run on fossil fuel (petrol and diesel) is a major cause of air pollution in cities and, along highways., , Natural Resources, , Chapter2.p65, , 17, , 17, , 4/9/2004, 5:07 PM
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Air pollution leads to acute and chronic respiratory diseases such as various lung infections,, asthma and even cancer., 2) Hydrosphere, •, , Clean water for drinking (a metabolic requirement for living processes)., , •, , Water for washing and cooking., , •, , Water used in agriculture and industry., , •, , Food resources from the sea, including fish,, crustacea, sea weed, etc., , •, , Food from fresh water sources, including, fish, crustacea and aquatic plants., , •, , Water flowing down from mountain ranges, harnessed to generate electricity in hydroelectric projects., , The hydrosphere covers three quarters of the, earth’s surface. A major part of the hydrosphere, is the marine ecosystem in the ocean, while only, a small part occurs in fresh water. Fresh water, in rivers, lakes and glaciers, is perpetually being, renewed by a process of evaporation and rainfall. Some of this fresh water lies in underground, aquifers. Human activities such as deforestation, create serious changes in the hydrosphere. Once, land is denuded of vegetation, the rain erodes, the soil which is washed into the sea., , 3) Lithosphere, •, , Soil, the basis for agriculture to provide us, with food., , •, , Stone, sand and gravel, used for construction., , •, , Micronutrients in soil, essential for plant, growth., , •, , Microscopic flora, small soil fauna and fungi, in soil, important living organisms of the, lithosphere, which break down plant litter, as well as animal wastes to provide nutrients for plants., , •, , A large number of minerals on which our, industries are based., , •, , Oil, coal and gas, extracted from underground sources. It provides power for vehicles, agricultural machinery, industry, and, for our homes., , The lithosphere began as a hot ball of matter, which formed the earth about 4.6 billion years, ago. About 3.2 billion years ago, the earth, cooled down considerably and a very special, event took place - life began on our planet. The, crust of the earth is 6 or 7 kilometers thick and, lies under the continents. Of the 92 elements in, the lithosphere only eight are common constituents of crustal rocks. Of these constituents, 47%, is oxygen, 28% is silicon, 8% is aluminium, 5%, is iron, while sodium, magnesium, potassium, and calcium constitute 4% each. Together,, these elements form about 200 common mineral compounds. Rocks, when broken down,, form soil on which man is dependent for his, agriculture. Their minerals are also the raw material used in various industries., Environmental Studies for Undergraduate Courses, , 18, , Chapter2.p65, , Chemicals from industry and sewage find their, way into rivers and into the sea. Water pollution thus threatens the health of communities, as all our lives depend on the availability of clean, water. This once plentiful resource is now becoming rare and expensive due to pollution., , 18, , 4/9/2004, 5:07 PM
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4) Biosphere, •, , Food, from crops and domestic animals,, providing human metabolic requirements., , •, , Food, for all forms of life which live as interdependent species in a community and, form food chains in nature on which man is, dependent., , •, , Energy needs: Biomass fuel wood collected, from forests and plantations, along with, other forms of organic matter, used as a, source of energy., , •, , Timber and other construction materials., , This is the relatively thin layer on the earth in, which life can exist. Within it the air, water, rocks, and soil and the living creatures, form structural, and functional ecological units, which together, can be considered as one giant global living system, that of our Earth itself. Within this framework, those characterised by broadly similar, geography and climate, as well as communities, of plant and animal life can be divided for convenience into different biogeographical realms., These occur on different continents. Within, these, smaller biogeographical units can be identified on the basis of structural differences and, functional aspects into distinctive recognizable, ecosystems, which give a distinctive character, to a landscape or waterscape. Their easily visible and identifiable characteristics can be described at different scales such as those of a, country, a state, a district or even an individual, valley, hill range, river or lake., The simplest of these ecosystems to understand, is a pond. It can be used as a model to understand the nature of any other ecosystem and to, appreciate the changes over time that are seen, in any ecosystem. The structural features of a, pond include its size, depth and the quality of, its water. The periphery, the shallow part and, the deep part of the pond, each provide specific conditions for different plant and animal, communities. Functionally, a variety of cycles, , such as the amount of water within the pond at, different times of the year, the quantity of nutrients flowing into the pond from the surrounding terrestrial ecosystem, all affect the ‘nature’, of the pond., Natural cycles between the spheres: All four, spheres are closely inter-linked systems and are, dependent on the integrity of each other. Disturbing one of these spheres in our environment, affects all the others., The linkages between them are mainly in the, form of cycles. For instance, the atmosphere,, hydrosphere and lithosphere are all connected, through the hydrological cycle. Water evaporated from the hydrosphere (the seas and freshwater ecosystems), forms clouds in the atmosphere. This becomes rain, which provides moisture for the lithosphere, on which life depends., The rain also acts on rocks as an agent of erosion and over millions of years has created soil,, on which plant life grows. Atmospheric movements in the form of wind, break down rocks, into soil. The most sensitive and complex linkages are those between the atmosphere, the, hydrosphere and the lithosphere on the one, hand, with the millions of living organisms in, the biosphere on the other. All living organisms, which exist on earth live only in the relatively, thin layer of the lithosphere and hydrosphere, that is present on the surface of land and in the, water. The biosphere which they form has, countless associations with different parts of the, three other ‘spheres’., It is therefore essential to understand the interrelationships of the separate entities soil, water, air and living organisms, and to appreciate, the value of preserving intact ecosystems as a, whole., , Natural Resources, , Chapter2.p65, , 19, , 19, , 4/9/2004, 5:07 PM
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Activity 1:, Observe a nearby pond in different seasons and document the seasonal, changes in it. One can also observe, changes in a river or the seasonal, changes in a forest or grassland., , Activity 2:, Take a simple object in daily use and, track its components back to each of its, spheres., Eg: this textbook: paper from wood –, biosphere, Water for pulping – hydrosphere, Bleach to whiten paper – a mineral, from lithosphere, , 2.2 RENEWABLE AND NON-RENEWABLE RESOURCES, Ecosystems act as resource producers and processors. Solar energy is the main driving force, of ecological systems, providing energy for the, growth of plants in forests, grasslands and, aquatic ecosystems. A forest recycles its plant, material slowly by continuously returning its, dead material, leaves, branches, etc. to the soil., Grasslands recycle material much faster than, forests as the grass dries up after the rains are, over every year. All the aquatic ecosystems are, also solar energy dependent and have cycles of, growth when plant life spreads and aquatic, animals breed. The sun also drives the water, cycle., Our food comes from both natural and agricultural ecosystems. Traditional agricultural ecosystems that depended on rainfall have been modified in recent times to produce more and more, food by the addition of extra chemicals and, , To manufacture consumer products, industry, requires raw materials from nature, including, water, minerals and power. During the manufacturing process, the gases, chemicals and, waste products pollute our environment, unless, the industry is carefully managed to clean up, this mess., , 2.2.1 Natural resources and associated problems, The unequal consumption of natural resources: A major part of natural resources are, today consumed in the technologically advanced, or ‘developed’ world, usually termed ‘the North’., The ‘developing nations’ of ‘the South’, including India and China, also over use many resources because of their greater human population. However, the consumption of resources, per capita (per individual) of the developed countries is up to 50 times greater than in most developing countries. Advanced countries produce, over 75% of global industrial waste and greenhouse gases., Energy from fossil fuels is consumed in relatively, much greater quantities in developed countries., Their per capita consumption of food too is, much greater as well as their waste of enormous quantities of food and other products,, such as packaging material, used in the food, industry. The USA for example with just 4% of, Environmental Studies for Undergraduate Courses, , 20, , Chapter2.p65, , water from irrigation systems but are still dependent on solar energy for the growth of crops., Moreover modern agriculture creates a variety, of environmental problems, which ultimately, lead to the formation of unproductive land., These include irrigation, which leads to the, development of saline soil, and the use of artificial fertilizers eventually ruin soil quality, and, pesticides, which are a health hazard for, humans as well as destroying components vital, to the long-term health of agricultural ecosystems., , 20, , 4/9/2004, 5:07 PM
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the world’s population consumes about 25%, of the world’s resources., Producing animal food for human consumption, requires more land than growing crops. Thus, countries that are highly dependent on non-vegetarian diets need much larger areas for, pastureland than those where the people are, mainly vegetarian., , Planning Landuse: Land itself is a major resource, needed for food production, animal, husbandry, industry, and for our growing human settlements. These forms of intensive landuse are frequently extended at the cost of ‘wild, lands’, our remaining forests, grasslands, wetlands and deserts. Thus it is essential to evolve a, rational land-use policy that examines how much, land must be made available for different purposes and where it must be situated. For instance, there are usually alternate sites at which, industrial complexes or dams can be built, but a, natural wilderness cannot be recreated artificially. Scientists today believe that at least 10, percent of land and water bodies of each ecosystem must be kept as wilderness for the longterm needs of protecting nature and natural, resources., , Land as a resource is now under serious pressure due to an increasing ‘land hunger’ - to produce sufficient quantities of food for an exploding human population. It is also affected by degradation due to misuse. Land and water resources are polluted by industrial waste and rural and urban sewage. They are increasingly, being diverted for short-term economic gains, to agriculture and industry. Natural wetlands of, great value are being drained for agriculture and, other purposes. Semi-arid land is being irrigated, and overused., The most damaging change in landuse is demonstrated by the rapidity with which forests have, vanished during recent times, both in India and, in the rest of the world. Forests provide us with, a variety of services. These include processes, such as maintaining oxygen levels in the atmosphere, removal of carbon dioxide, control over, water regimes, and slowing down erosion and, also produce products such as food, fuel, timber, fodder, medicinal plants, etc. In the long, term, the loss of these is far greater than the, short-term gains produced by converting forested lands to other uses., , Natural Resources, , Chapter2.p65, , 21, , 21, , 4/9/2004, 5:07 PM
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The need for sustainable lifestyles: The quality of human life and the quality of ecosystems, on earth are indicators of the sustainable use of, resources. There are clear indicators of sustainable lifestyles in human life., •, , Increased longevity, , •, , An increase in knowledge, , •, , An enhancement of income., , 2.2.3 Renewable resources, Though water and biological living resources are, considered renewable. They are in fact renewable only within certain limits. They are linked, to natural cycles such as the water cycle., •, , Fresh water (even after being used) is evaporated by the sun’s energy, forms water, vapour and is reformed in clouds and falls, to earth as rain. However, water sources, can be overused or wasted to such an extent that they locally run dry. Water sources, can be so heavily polluted by sewage and, toxic substances that it becomes impossible, to use the water., , •, , Forests, once destroyed take thousands of, years to regrow into fully developed natural ecosystems with their full complement, of species. Forests thus can be said to behave like non-renewable resources if overused., , •, , Fish are today being over-harvested until the, catch has become a fraction of the original, resource and the fish are incapable of breeding successfully to replenish the population., , •, , The output of agricultural land if mismanaged drops drastically., , •, , When the population of a species of plant, or animal is reduced by human activities,, until it cannot reproduce fast enough to, maintain a viable number, the species becomes extinct., , •, , Many species are probably becoming extinct, without us even knowing, and other linked, species are affected by their loss., , These three together are known as the ‘Human, development index’., The quality of the ecosystems have indicators, that are more difficult to assess., •, , A stabilized population., , •, , The long term conservation of biodiversity., , •, , The careful long-term use of natural resources., , •, , The prevention of degradation and pollution of the environment., , 2.2.2 Non-renewable resources, These are minerals that have been formed in, the lithosphere over millions of years and constitute a closed system. These non-renewable, resources, once used, remain on earth in a different form and, unless recycled, become waste, material., Non-renewable resources include fossil fuels, such as oil and coal, which if extracted at the, present rate, will soon be totally used up. The, end products of fossil fuels are in the form of, heat and mechanical energy and chemical compounds, which cannot be reconstituted as a resource., , Environmental Studies for Undergraduate Courses, , 22, , Chapter2.p65, , 22, , 4/9/2004, 5:07 PM
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The Dodo of Madagascar and the Cheetah, in India are well known examples of extinct, species. What is however not generally recognized is that thousands of extinctions of, small plants and animals are occurring every, year due to loss of their habitat. Over harvesting and poaching threaten the existence, of many others., , Activity 3: Utilisation of resources, The use of a resource begins with its collection, its processing into a useable product,, and transport through a delivery system,, to the consumer who uses it. It also involves, disposal of the waste products produced at, each step. Each step in resource use can affect the environment for better or worse., The control of these steps is known as environmental management., Think of a resource you use and track it, through these steps., Eg. The cotton in the clothes you are wearing. At each step note:, •, , What other resources are needed at this, step to move the resource you chose to, the next?, , •, , What waste products are generated at, that step?, , •, , How are they likely to be disposed off?, , •, , What pollutants are generated in the, process?, , a) Forest Resources, Use and overexploitation: Scientists estimate, that India should ideally have 33 percent of its, land under forests. Today we have only about, 12 percent. Thus we need not only to protect, existing forests but also to increase our forest, cover., People who live in or near forests know the value, of forest resources first hand because their lives, and livelihoods depend directly on these resources. However, the rest of us also derive great, benefits from the forests which we are rarely, aware of. The water we use depends on the, existence of forests on the watersheds around, river valleys. Our homes, furniture and paper are, made from wood from the forest. We use many, medicines that are based on forest produce. And, we depend on the oxygen that plants give out, and the removal of carbon dioxide we breathe, out from the air., Forests once extended over large tracts of our, country. People have used forests in our country for thousands of years. As agriculture spread, the forests were left in patches which were controlled mostly by tribal people. They hunted animals and gathered plants and lived entirely on, forest resources. Deforestation became a major, concern in British times when a large amount, of timber was extracted for building their ships., This led the British to develop scientific forestry, in India. They however alienated local people, by creating Reserved and Protected Forests, which curtailed access to the resources. This led, to a loss of stake in the conservation of the forests which led to a gradual degradation and, fragmentation of forests across the length and, breadth of the country., Another period of overutilisation and forest degradation occurred in the early period following, independence as people felt that now that the, British had gone they had a right to using our, forests in any way we pleased. The following, , Natural Resources, , Chapter2.p65, , 23, , 23, , 4/9/2004, 5:07 PM
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FOREST FUNCTIONS, Watershed protection:, • Reduce the rate of surface run-off of water., • Prevent flash floods and soil erosion., • Produces prolonged gradual run-off and thus prevent effects of drought., Atmospheric regulation:, • Absorption of solar heat during evapo-transpiration., • Maintaining carbon dioxide levels for plant growth., • Maintaining the local climatic conditions., Erosion control:, • Holding soil (by preventing rain from directly washing soil away)., Land bank:, • Maintenance of soil nutrients and structure., Local use - Consumption of forest produce by local people who collect it for subsistence –, (Consumptive use), • Food - gathering plants, fishing, hunting from the forest., (In the past when wildlife was plentiful, people could hunt and kill animals for, food. Now that populations of most wildlife species have diminished, continued, hunting would lead to extinction.), • Fodder - for cattle., • Fuel wood and charcoal for cooking, heating., • Poles - building homes especially in rural and wilderness areas., • Timber – household articles and construction., • Fiber - weaving of baskets, ropes, nets, string, etc., • Sericulture – for silk., • Apiculture - bees for honey, forest bees also pollinate crops., • Medicinal plants - traditionally used medicines, investigating them as potential, source for new modern drugs., Market use - (Productive use), • Most of the above products used for consumptive purposes are also sold as a, source of income for supporting the livelihoods of forest dwelling people., • Minor forest produce - (non-wood products): Fuelwood, fruit, gum, fiber, etc., which are collected and sold in local markets as a source of income for forest, dwellers., • Major timber extraction - construction, industrial uses, paper pulp, etc. Timber, extraction is done in India by the Forest Department, but illegal logging continues, in many of the forests of India and the world., , Environmental Studies for Undergraduate Courses, , 24, , Chapter2.p65, , 24, , 4/9/2004, 5:07 PM
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years saw India’s residual forest wealth dwindle, sharply. Timber extraction continued to remain, the Forest Department’s main concern up to the, 1970s. The fact that forest degradation and, deforestation was creating a serious loss of the, important functions of the forest began to override its utilisation as a source of revenue from, timber., , Deforestation: Where civilizations have looked, after forests by using forest resources cautiously,, they have prospered, where forests were destroyed, the people were gradually impoverished. Today logging and mining are serious, causes of loss of forests in our country and all, over the world. Dams built for hydroelectric, power or irrigation have submerged forests and, have displaced tribal people whose lives are, closely knit to the forest. This has become a serious cause of concern in India., One of India’s serious environmental problems, is forest degradation due to timber extraction, and our dependence on fuelwood. A large number of poor rural people are still highly dependent on wood to cook their meals and heat their, homes. We have not been able to plant enough, trees to support the need for timber and, fuelwood., The National Forest Policy of 1988 now gives an, added importance to JFM. Another resolution, in 1990 provided a formal structure for community participation though the formation of, Village Forest Committees. Based on these experiences, new JFM guidelines were issued in, 2000. This stipulates that at least 25 per cent of, the income from the area must go to the community. From the initiation of the program, until 2002, there were 63,618 JFM Committees, managing over 140,953 sq. km of forest under, JFM in 27 States in India., The States have tried a variety of approaches to, JFM. The share for village forest committees, , CASE STUDY, Joint Forest Management, The need to include local communities in, Forest Management has become a growing, concern. Local people will only support, greening an area if they can see some economic benefit from conservation. An informal arrangement between local communities and the Forest Department began in, 1972, in Midnapore District of West Bengal., JFM has now evolved into a formal agreement which identifies and respects the local, community’s rights and benefits that they, need from forest resources. Under JFM, schemes, Forest Protection Committees from, local community members are formed. They, participate in restoring green cover and protect the area from being over exploited., , ranges from 25 per cent in Kerala to 100 per, cent in Andhra Pradesh, 50 per cent in Gujarat,, Maharashtra, Orissa and Tripura. In many States, 25 per cent of the revenue is used for village, development. In many States non-timber forest, products (NTFPs) are available for people free, of cost., Some States have stopped grazing completely;, some have rotational grazing schemes which, have helped in forest regeneration., , Timber extraction, mining and dams are invariably parts of the needs of a developing country. If timber is overharvested the ecological functions of the forest are lost. Unfortunately forests are located in areas where there are rich, mineral resources. Forests also cover the steep, embankments of river valleys, which are ideally, suited to develop hydel and irrigation projects., Thus there is a constant conflict of interests be-, , Natural Resources, , Chapter2.p65, , 25, , 25, , 4/9/2004, 5:07 PM
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tween the conservation interests of environmental scientists and the Mining and Irrigation Departments. What needs to be understood is that, long-term ecological gains cannot be sacrificed, for short-term economic gains that unfortunately lead to deforestation. These forests where, development projects are planned, can displace, thousands of tribal people who lose their homes, when these plans are executed. This leads to, high levels of suffering for which there is rarely, a satisfactory answer., , b) Water resources, The water cycle, through evaporation and precipitation, maintains hydrological systems which, form rivers and lakes and support in a variety of, aquatic ecosystems. Wetlands are intermediate, forms between terrestrial and aquatic ecosystems and contain species of plants and animals, that are highly moisture dependent. All aquatic, ecosystems are used by a large number of people, for their daily needs such as drinking water,, washing, cooking, watering animals, and irrigating fields. The world depends on a limited, quantity of fresh water. Water covers 70% of, the earth’s surface but only 3% of this is fresh, water. Of this, 2% is in polar ice caps and only, 1% is usable water in rivers, lakes and subsoil, aquifers. Only a fraction of this can be actually, used. At a global level 70% of water is used for, agriculture about 25% for industry and only 5%, for domestic use. However this varies in different countries and industrialized countries use a, greater percentage for industry. India uses 90%, for agriculture, 7% for industry and 3% for, domestic use., One of the greatest challenges facing the world, in this century is the need to rethink the overall, management of water resources. The world, population has passed the 6 billion mark. Based, on the proportion of young people in developing countries, this will continue to increase significantly during the next few decades. This, , Local conflicts are already spreading to states., Eg. Karnataka and Tamil Nadu over the waters, of the Krishna., India is expected to face critical levels of water, stress by 2025. At the global level 31 countries, are already short of water and by 2025 there, will be 48 countries facing serious water shortages. The UN has estimated that by the year, 2050, 4 billion people will be seriously affected, by water shortages. This will lead to multiple, conflicts between countries over the sharing of, water. Around 20 major cities in India face, chronic or interrupted water shortages. There, are 100 countries that share the waters of 13, large rivers and lakes. The upstream countries, could starve the downstream nations leading to, political unstable areas across the world. Examples are Ethopia, which is upstream on the, Nile and Egypt, which is downstream and highly, dependent on the Nile. International accords, that will look at a fair distribution of water in, such areas will become critical to world peace., India and Bangladesh already have a negotiated, agreement on the water use of the Ganges., , Overutilization and pollution of surface and, groundwater: With the growth of human, population there is an increasing need for larger, amounts of water to fulfill a variety of basic, needs. Today in many areas this requirement, cannot be met. Overutilization of water occurs, at various levels. Most people use more water, than they really need. Most of us waste water, Environmental Studies for Undergraduate Courses, , 26, , Chapter2.p65, , places enormous demands on the world’s limited freshwater supply. The total annual freshwater withdrawals today are estimated at 3800, cubic kilometers, twice as much as just 50 years, ago (World Commission on Dams, 2000). Studies indicate that a person needs a minimum of, 20 to 40 liters of water per day for drinking and, sanitation. More than one billion people worldwide have no access to clean water, and to many, more, supplies are unreliable., , 26, , 4/9/2004, 5:07 PM
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during a bath by using a shower or during washing of clothes. Many agriculturists use more, water than necessary to grow crops. There are, many ways in which farmers can use less water, without reducing yields such as the use of drip, irrigation systems., Agriculture also pollutes surface water and underground water stores by the excessive use of, chemical fertilizers and pesticides. Methods such, as the use of biomass as fertilizer and non toxic, pesticides such as neem products and using integrated pest management systems reduces the, agricultural pollution of surface and ground, water., Industry tends to maximise short-term economic, gains by not bothering about its liquid waste, and releasing it into streams, rivers and the sea., In the longer term, as people become more conscious of using ‘green products’ made by, ecosensitive industries, the polluter’s products, may not be used. The polluting industry that, does not care for the environment and pays off, bribes to get away from the cost needed to use, effluent treatment plants may eventually be, caught, punished and even closed down. Public, awareness may increasingly put pressures on, industry to produce only eco-friendly products, which are already gaining in popularity., As people begin to learn about the serious health, hazards caused by pesticides in their food, public awareness can begin putting pressures on, farmers to reduce the use of chemicals that are, injurious to health., CASE STUDY, , Global climate change: Changes in climate at, a global level caused by increasing air pollution, have now begun to affect our climate. In some, regions global warming and the El Nino winds, have created unprecedented storms. In other, areas, they lead to long droughts. Everywhere, the ‘greenhouse effect’ due to atmospheric, pollution is leading to increasingly erratic and, unpredictable climatic effects. This has seriously, affected regional hydrological conditions., , Floods: Floods have been a serious environmental hazard for centuries. However, the havoc, raised by rivers overflowing their banks has become progressively more damaging, as people, have deforested catchments and intensified use, of river flood plains that once acted as safety, valves. Wetlands in flood plains are nature’s, flood control systems into which overfilled rivers could spill and act like a temporary sponge, holding the water, and preventing fast flowing, water from damaging surrounding land., Deforestation in the Himalayas causes floods, that year after year kill people, damage crops, and destroy homes in the Ganges and its tributaries and the Bramhaputra. Rivers change their, course during floods and tons of valuable soil is, lost to the sea. As the forests are degraded, rainwater no longer percolates slowly into the subsoil but runs off down the mountainside bearing large amounts of topsoil. This blocks rivers, temporarily but gives way as the pressure, mounts allowing enormous quantities of water, to wash suddenly down into the plains below., There, rivers swell, burst their banks and flood, waters spread to engulf peoples’ farms and, homes., , Water pollution - Nepal, The Narayani River of Nepal has been polluted by factories located on its bank. This, has endangered fish, dolphins, crocodiles and, other flora and fauna of the region., , Drought: In most arid regions of the world the, rains are unpredictable. This leads to periods, when there is a serious scarcity of water to drink,, use in farms, or provide for urban and industrial, use. Drought prone areas are thus faced with, , Natural Resources, , Chapter2.p65, , 27, , 27, , 4/9/2004, 5:07 PM
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irregular periods of famine. Agriculturists have, no income in these bad years, and as they have, no steady income, they have a constant fear of, droughts. India has ‘Drought Prone Areas Development Programs’, which are used in such, areas to buffer the effects of droughts. Under, these schemes, people are given wages in bad, years to build roads, minor irrigation works and, plantation programs., Drought has been a major problem in our country especially in arid regions. It is an unpredictable climatic condition and occurs due to the, failure of one or more monsoons. It varies in, frequency in different parts of our country., While it is not feasible to prevent the failure of, the monsoon, good environmental management can reduce its ill effects. The scarcity of, water during drought years affects homes, agriculture and industry. It also leads to food shortages and malnutrition which especially affects, children., Several measures can be taken to minimise the, serious impacts of a drought. However this must, be done as a preventive measure so that if the, monsoons fail its impact on local people’s lives, is minimised., In years when the monsoon is adequate, we use, up the good supply of water without trying to, conserve it and use the water judiciously. Thus, during a year when the rains are poor, there is, no water even for drinking in the drought area., One of the factors that worsens the effect of, drought is deforestation. Once hill slopes are, denuded of forest cover the rainwater rushes, down the rivers and is lost. Forest cover permits, water to be held in the area permitting it to, seep into the ground. This charges the underground stores of water in natural aquifers. This, can be used in drought years if the stores have, been filled during a good monsoon. If water, from the underground stores is overused, the, , Water for Agriculture and Power Generation: India’s increasing demand for water for, intensive irrigated agriculture, for generating, electricity, and for consumption in urban and, industrial centers, has been met by creating large, dams. Irrigated areas increased from 40 million, ha. in 1900 to 100 million ha. in 1950 and to, 271 million ha. by 1998. Dams support 30 to, 40% of this area., Although dams ensure a year round supply of, water for domestic use, provide extra water for, agriculture, industry, hydropower generation,, they have several serious environmental problems. They alter river flows, change nature’s, flood control mechanisms such as wetlands and, flood plains, and destroy the lives of local people, and the habitats of wild plant and animal species., Irrigation to support cash crops like sugarcane, produces an unequal distribution of water. Large, landholders on the canals get the lion’s share of, water, while poor, small farmers get less and, are seriously affected., , Sustainable water management: ‘Save water’ campaigns are essential to make people, everywhere aware of the dangers of water scarcity. A number of measures need to be taken, for the better management of the world’s water resources. These include measures such as:, •, , Building several small reservoirs instead of, few mega projects., , •, , Develop small catchment dams and protect, wetlands., , Environmental Studies for Undergraduate Courses, , 28, , Chapter2.p65, , water table drops and vegetation suffers. This, soil and water management and afforestation, are long-term measures that reduce the impact, of droughts., , 28, , 4/9/2004, 5:07 PM
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•, , Soil management, micro catchment development and afforestation permits recharging of underground aquifers thus reducing, the need for large dams., , •, , Treating and recycling municipal waste, water for agricultural use., , have built around 57% of the world’s large, dams., , Dams problems, , •, , Preventing leakages from dams and canals., , •, , Preventing loss in Municipal pipes., , •, , Effective rain water harvesting in urban, environments., , •, , Water conservation measures in agriculture, such as using drip irrigation., , •, , Pricing water at its real value makes people, use it more responsibly and efficiently and, reduces water wasting., , •, , In deforested areas where land has been, degraded, soil management by bunding, along the hill slopes and making ‘nala’ plugs,, can help retain moisture and make it possible to re-vegetate degraded areas., , Managing a river system is best done by leaving, its course as undisturbed as possible. Dams and, canals lead to major floods in the monsoon and, the drainage of wetlands seriously affects areas, that get flooded when there is high rainfall., , Dams: Today there are more than 45,000 large, dams around the world, which play an important role in communities and economies that, harness these water resources for their economic, development. Current estimates suggest some, 30-40% of irrigated land worldwide relies on, dams. Hydropower, another contender for the, use of stored water, currently supplies 19% of, the world’s total electric power supply and is, used in over 150 countries. The world’s two, most populous countries – China and India –, , •, , Fragmentation and physical transformation, of rivers., , •, , Serious impacts on riverine ecosystems., , •, , Social consequences of large dams due to, displacement of people., , •, , Water logging and salinisation of surrounding lands., , •, , Dislodging animal populations, damaging, their habitat and cutting off their migration, routes., , •, , Fishing and travel by boat disrupted., , •, , The emission of green house gases from, reservoirs due to rotting vegetation and, carbon inflows from the catchment is a recently identified impact., , Large dams have had serious impacts on the, lives, livelihoods, cultures and spiritual existence, of indigenous and tribal peoples. They have suffered disproportionately from the negative impacts of dams and often been excluded from, sharing the benefits. In India, of the 16 to 18, million people displaced by dams, 40 to 50%, were tribal people, who account for only 8% of, our nation’s one billion people., Conflicts over dams have heightened in the last, two decades because of their social and environmental impacts and failure to achieve targets for sticking to their costs as well as achieving promised benefits. Recent examples show, how failure to provide a transparent process that, includes effective participation of local people, has prevented affected people from playing an, , Natural Resources, , Chapter2.p65, , 29, , 29, , 4/9/2004, 5:07 PM
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active role in debating the pros and cons of the, project and its alternatives. The loss of traditional, local controls over equitable distribution, remains a major source of conflict., , In India, a national assessment of dam, projects cleared in the 1980s and 90s shows, that in 90% of cases the project authorities, have not fulfilled the environmental conditions under which environmental clearance, was given by the GOI under the EPA of 1986., , CASE STUDY, Sardar Sarovar Project, The World Bank’s withdrawal from the, Sardar Sarovar Project in India in 1993 was, a result of the demands of local people, threatened with the loss of their livelihoods, and homes in the submergence area., This dam in Gujarat on the Narmada has displaced thousands of tribal folk, whose lives, and livelihoods were linked to the river, the, forests and their agricultural lands. While, they and the fishermen at the estuary, have, lost their homeland, rich farmers downstream will get water for agriculture. The, question is why should the local tribals be, made homeless, displaced and relocated to, benefit other people? Why should the less, fortunate be made to bear the costs of development for better off farmers? It is a question of social and economic equity as well as, the enormous environmental losses, including loss of the biological diversity of the inundated forests in the Narmada valley., , Activity 4:, How much water is needed by one person?, Several international agencies and experts, have proposed that 50 liters per person per, day covers basic human water requirements, for drinking, sanitation, bathing and food, preparation. Estimate your average daily, consumption., , c) Mineral Resources, A mineral is a naturally occurring substance of, definite chemical composition and identifiable, physical properties. An ore is a mineral or combination of minerals from which a useful substance, such as a metal, can be extracted and, used to manufacture a useful product., Minerals are formed over a period of millions of, years in the earth’s crust. Iron, aluminum, zinc,, manganese and copper are important raw materials for industrial use. Important non-metal, resources include coal, salt, clay, cement and, silica. Stone used for building material, such as, granite, marble, limestone, constitute another, category of minerals. Minerals with special properties that humans value for their aesthetic and, ornamental value are gems such as diamonds,, emeralds, rubies. The luster of gold, silver and, platinum is used for ornaments. Minerals in the, form of oil, gas and coal were formed when, ancient plants and animals were converted into, underground fossil fuels., Minerals and their ores need to be extracted, from the earth’s interior so that they can be, used. This process is known as mining. Mining, operations generally progress through four, stages:, (1) Prospecting: Searching for minerals., (2) Exploration: Assessing the size, shape, location, and economic value of the deposit., Environmental Studies for Undergraduate Courses, , 30, , Chapter2.p65, , 30, , 4/9/2004, 5:07 PM
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(3) Development: Work of preparing access to, the deposit so that the minerals can be extracted from it., (4) Exploitation: Extracting the minerals from, the mines., In the past, mineral deposits were discovered, by prospectors in areas where mineral deposits, in the form of veins were exposed on the surface. Today, however, prospecting and exploration is done by teams of geologists, mining, engineers, geophysicists, and geochemists who, work together to discover new deposits. Modern prospecting methods include the use of sophisticated instruments like GIS to survey and, study the geology of the area., The method of mining has to be determined, depending on whether the ore or mineral deposit is nearer the surface or deep within the, earth. The topography of the region and the, physical nature of the ore deposit is studied., Mines are of two types – surface (open cut or, strip mines) or deep or shaft mines. Coal, metals and non-metalliferous minerals are all mined, differently depending on the above criteria. The, method chosen for mining will ultimately depend on how maximum yield may be obtained, under existing conditions at a minimum cost,, with the least danger to the mining personnel., Most minerals need to be processed before they, become usable. Thus ‘technology’ is dependent, on both the presence of resources and the energy necessary to make them ‘usable’., , Mine safety: Mining is a hazardous occupation, and the safety of mine workers is an important environmental consideration of the industry. Surface mining is less hazardous than, underground mining. Metal mining is less hazardous than coal mining. In all underground, mines, rock and roof falls, flooding, and inad-, , CASE STUDY, Sariska Tiger Reserve, Rajasthan, The Forest Department has leased land for, mining in the Sariska Tiger Reserve area by, denotifying forest areas. The local people, have fought against the mining lobby, and, have filed a Public Interest Litigation in the, Supreme Court in 1991. Rajendra Singh, secretary of TBS, points out that as many as 70, mines operate in close proximity to the forest., , equate ventilation are the greatest hazards., Large explosions have occured in coal mines,, killing many miners. More miners have suffered, from disasters due to the use of explosives in, metal mines., Mining poses several long-term occupational, hazards to the miners. Dust produced during, mining operations is injurious to health and, causes a lung disease known as black lung, or, pneumoconiosis. Fumes generated by incomplete dynamite explosions are extremely poisonous. Methane gas, emanating from coal strata,, is hazardous to health although not poisonous, in the concentrations usually encountered in, mine air. Radiation is a hazard in uranium, mines., , Environmental problems: Mining operations, are considered one of the main sources of environmental degradation. The extraction of all, these products from the lithosphere has a variety of side effects. Depletion of available land, due to mining, waste from industries, conversion of land to industry and pollution of land,, water and air by industrial wastes, are environmental side effects of the use of these non-renewable resources. Public awareness of this, , Natural Resources, , Chapter2.p65, , 31, , 31, , 4/9/2004, 5:07 PM
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problem is of a global nature and government, actions to stem the damage to the natural environment have led to numerous international, agreements and laws directed toward the prevention of activities and events that may adversely affect the environment., , irrigation. The Green Revolution of the 60’s reduced starvation in the country. However many, of the technologies we have used to achieve, this are now being questioned., •, , Our fertile soils are being exploited faster, than they can recuperate., , d) Food resources, , •, , Forests, grasslands and wetlands have been, converted to agricultural use, which has led, to serious ecological questions., , •, , Our fish resources, both marine and inland,, show evidence of exhaustion., , •, , There are great disparities in the availability, of nutritious food. Some communities such, as tribal people still face serious food problems leading to malnutrition especially, among women and children., , Today our food comes almost entirely from agriculture, animal husbandry and fishing. Although India is self-sufficient in food production, it is only because of modern patterns of, agriculture that are unsustainable and which, pollute our environment with excessive use of, fertilizers and pesticides., The FAO defines sustainable agriculture as that, which conserves land, water and plant and animal genetic resources, does not degrade the, environment and is economically viable and socially acceptable. Most of our large farms grow, single crops (monoculture). If this crop is hit by, a pest, the entire crop can be devastated, leaving the farmer with no income during the year., On the other hand, if the farmer uses traditional, varieties and grows several different crops, the, chance of complete failure is lowered considerably. Many studies have shown that one can, use alternatives to inorganic fertilizers and pesticides. This is known as Integrated Crop Management., , World food problems: In many developing, countries where populations are expanding rapidly, the production of food is unable to keep, pace with the growing demand. Food production in 64 of the 105 developing countries is, lagging behind their population growth levels., These countries are unable to produce more, food, or do not have the financial means to import it. India is one of the countries that have, been able to produce enough food by cultivating a large proportion of its arable land through, , Women play an extremely vital role in food production as well as cooking the meal and feeding children. In most rural communities they have, the least exposure to technical training and to, health workers trained in teaching/learning on, issues related to nutritional aspects. Women and, girls frequently receive less food than the men., These disparities need to be corrected., In India there is a shortage of cultivable productive land. Thus farm sizes are too small to support a family on farm produce alone. With each, generation, farms are being subdivided further., Environmental Studies for Undergraduate Courses, , 32, , Chapter2.p65, , These issues bring in new questions as to how, demands will be met in future even with a slowing of population growth. Today the world is, seeing a changing trend in dietary habits. As, living standards are improving, people are eating more non-vegetarian food. As people, change from eating grain to meat, the world’s, demand for feed for livestock based on agriculture increases as well. This uses more land per, unit of food produced and the result is that the, world’s poor do not get enough to eat., , 32, , 4/9/2004, 5:07 PM
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Poor environmental agricultural practices such, as slash and burn, shifting cultivation, or ‘rab’, (woodash) cultivation degrade forests., Globally 5 to 7 million hectares of farmland is, degraded each year. Loss of nutrients and overuse of agricultural chemicals are major factors, in land degradation. Water scarcity is an important aspect of poor agricultural outputs. Salinization and water logging has affected a large, amount of agricultural land worldwide., Loss of genetic diversity in crop plants is another, issue that is leading to a fall in agricultural produce. Rice, wheat and corn are the staple foods, of two thirds of the world’s people. As wild relatives of crop plants in the world’s grasslands,, wetlands and other natural habitats are being, lost, the ability to enhance traits that are resistant to diseases, salinity, etc. is lost. Genetic, engineering is an untried and risky alternative, to traditional cross breeding., , Food Security: It is estimated that 18 million, people worldwide, most of whom are children,, die each year due to starvation or malnutrition,, and many others suffer a variety of dietary deficiencies., The earth can only supply a limited amount of, food. If the world’s carrying capacity to produce, food cannot meet the needs of a growing population, anarchy and conflict will follow. Thus food, security is closely linked with population control, through the family welfare program. It is also, linked to the availability of water for farming., Food security is only possible if food is equitably, distributed to all. Many of us waste a large, amount of food carelessly. This eventually places, great stress on our environmental resources., A major concern is the support needed for small, farmers so that they remain farmers rather than, shifting to urban centers as unskilled industrial, workers. International trade policies in regard, , to an improved flow of food across national, borders from those who have surplus to those, who have a deficit in the developing world is, another issue that is a concern for planners who, deal with International trade concerns. ‘Dumping’ of underpriced foodstuffs produced in the, developed world, onto markets in undeveloped, countries undermines prices and forces farmers, there to adopt unsustainable practices to compete., , Fisheries: Fish is an important protein food in, many parts of the world. This includes marine, and fresh water fish. While the supply of food, from fisheries increased phenomenally between, 1950 and 1990, in several parts of the world, fish catch has since dropped due to overfishing., In 1995 FAO reported that 44% of the world’s, fisheries are fully or heavily exploited, 16% are, already overexploited, 6% are depleted, and, only 3% are gradually recovering. Canada had, to virtually close down cod fishing in the 1990s, due to depletion of fish reserves., Modern fishing technologies using mechanized, trawlers and small meshed nets lead directly to, overexploitation, which is not sustainable. It is, evident that fish have to breed successfully and, need to have time to grow if the yield has to be, used sustainably. The worst hit are the small traditional fishermen who are no match for organized trawlers., , Loss of Genetic diversity: There are 50,000, known edible plants documented worldwide., Of these only 15 varieties produce 90% of the, world’s food. Modern agricultural practices have, resulted in a serious loss of genetic variability of, crops. India’s distinctive traditional varieties of, rice alone are said to have numbered between, 30 and 50 thousand. Most of these have been, lost to the farmer during the last few decades, as multinational seed companies push a few, commercial types., , Natural Resources, , Chapter2.p65, , 33, , 33, , 4/9/2004, 5:07 PM
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This creates a risk to our food security, as farmers can loose all their produce due to a rapidly, spreading disease. A cereal that has multiple, varieties growing in different locations does not, permit the rapid spread of a disease., The most effective method to introduce desirable traits into crops is by using characteristics, found in the wild relatives of crop plants. As the, wilderness shrinks, these varieties are rapidly, disappearing. Once they are lost, their desirable, characteristics cannot be introduced when, found necessary in future. Ensuring long-term, food security may depend on conserving wild, relatives of crop plants in National Parks and, Wildlife Sanctuaries., If plant genetic losses worldwide are not slowed, down, some estimates show that as many as, 60,000 plant species, which accounts for 25%, of the world’s total, will be lost by the year 2025., The most economical way to prevent this is by, expanding the network and coverage of our, Protected Areas. Collections in germplasm, seed, banks and tissue culture facilities, are other possible ways to prevent extinction but are extremely expensive., Scientists now believe that the world will soon, need a second green revolution to meet our, future demands of food based on a new ethic, of land and water management that must be, based on values which include environmental, sensitivity, equity, biodiversity conservation of, cultivars and insitu preservation of wild relatives, of crop plants. This must not only provide food, for all, but also work out more equitable distribution of both food and water, reduce agricultural dependence on the use of fertilizers and, pesticides (which have long term ill effects on, human wellbeing) and provide an increasing, support for preserving wild relatives of crop, plants in Protected Areas. Pollution of water, sources, land degradation and desertification, must be rapidly reversed. Adopting soil conservation measures, using appropriate farming, , Alternate food sources: Food can be, innovatively produced if we break out of the, current agricultural patterns. This includes working on new avenues to produce food, such as, using forests for their multiple non-wood forest, products, which can be used for food if harvested sustainably. This includes fruit, mushrooms, sap, gum, etc. This takes time, as people, must develop a taste for these new foods., , CASE STUDY, Israel began using drip irrigation systems as, it is short of water. With this technique, farmers have been able to improve the efficiency, of irrigation by 95%. Over a 20-year period,, Israel’s food production doubled without an, increase in the use of water for agriculture., In India, some traditional communities in, urban and semi urban towns used to grow, their own vegetables in backyards on wastewater from their own homes. Calcutta releases its waste water into surrounding lagoons in which fish are reared and the water is used for growing vegetables., , Medicines, both traditional and modern, can be, harvested sustainably from forests., Madagaskar’s Rosy Periwinkle used for childhood leukemia’s and Taxol from Western Yew, Environmental Studies for Undergraduate Courses, , 34, , Chapter2.p65, , techniques, especially on hill slopes, enhancing, the soil with organic matter, rotating crops and, managing watersheds at the micro level are a, key to agricultural production to meet future, needs. Most importantly food supply is closely, linked to the effectiveness of population control programs worldwide. The world needs better and sustainable methods of food production which is an important aspect of landuse, management., , 34, , 4/9/2004, 5:07 PM
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from the American Northwest as an anticancer, drug are examples of forest products used extensively in modern medicine. Without care,, commercial exploitation can lead to early extinction of such plants., Using unfamiliar crops such as Nagli, which are, grown on poor soil on hill slopes is another option. This crop grown in the Western Ghats now, has no market and is thus rarely grown. Only, local people use this nutritious crop themselves., It is thus not as extensively cultivated as in the, past. Popularising this crop could add to food, availability from marginal lands. Several crops, can be grown in urban settings, including vegetables and fruit which can be grown on waste, household water and fertilizers from, vermicomposting pits., Several foods can be popularized from yet unused seafood products such as seaweed as long, as this is done at sustainable levels. Educating, women about nutrition, who are more closely, involved with feeding the family, is an important aspect of supporting the food needs of, many developing countries., Integrated Pest Management includes preserving pest predators, using pest resistant seed, varieties and reducing the use of chemical fertilizers., , e) Energy resources, , Energy is defined by physicists as the capacity to do work. Energy is found on our, planet in a variety of forms, some of which, are immediately useful to do work, while others require a process of transformation., , The sun is the primary energy source in our lives., We use it directly for its warmth and through, various natural processes that provide us with, , food, water, fuel, and shelter. The, sun’s rays power, the growth of, plants, which form, our food material,, give off oxygen, which we breathe in and take up carbon dioxide that we breathe out. Energy from the sun, evaporates water from oceans, rivers and lakes,, to form clouds that turn into rain. Today’s fossil, fuels were once the forests that grew in prehistoric times due to the energy of the sun., Chemical energy, contained in chemical compounds is released when they are broken down, by animals in the presence of oxygen. In India,, manual labour is still extensively used to get work, done in agricultural systems, and domestic animals used to pull carts and ploughs. Electrical, energy produced in several ways, powers transport, artificial lighting, agriculture and industry., This comes from hydel power based on the, water cycle that is powered by the sun’s energy, that supports evaporation, or from thermal, power stations powered by fossil fuels. Nuclear, energy is held in the nucleus of an atom and is, now harnessed to develop electrical energy., We use energy for household use, agriculture,, production of industrial goods and for running, transport. Modern agriculture uses chemical, fertilizers, which require large amounts of energy during their, manufacture. Industry, uses energy to, p o w e r, manufacturing units and the urban complexes, that support it. Energy-demanding roads and, railway lines are built to transport products from, place to place and to reach raw materials in, mines and forests., , Natural Resources, , Chapter2.p65, , 35, , 35, , 4/9/2004, 5:07 PM
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No energy related technology is completely ‘risk, free’ and unlimited demands on energy increase, this risk factor many fold. All energy use creates, heat and contributes to atmospheric temperature. Many forms of energy release carbon dioxide and lead to global warming. Nuclear energy plants have caused enormous losses to the, environment due to the leakage of nuclear material. The inability to effectively manage and, safely dispose of nuclear waste is a serious, global concern., At present almost 2 billion people worldwide, have no access to electricity at all. While more, people will require electrical energy, those who, do have access to it continue to increase their, individual requirements. In addition, a large proportion of energy from electricity is wasted during transmission as well as at the user level. It is, broadly accepted that long-term trends in energy use should be towards a cleaner global, energy system that is less carbon intensive and, less reliant on finite non-renewable energy, sources. It is estimated that the currently used, methods of using renewable energy and non, renewable fossil fuel sources together will be, insufficient to meet foreseeable global demands, for power generation beyond the next 50 to, 100 years., Thus when we use energy wastefully, we are, contributing to a major environmental disaster, for our earth. We all need to become responsible energy users. An electrical light that is burning unnecessarily is a contributor to environmental degradation., , Growing energy needs: Energy has always, been closely linked to man’s economic growth, and development. Present strategies for development that have focused on rapid economic, growth have used energy utilization as an index, of economic development. This index however,, does not take into account the long-term ill effects on society of excessive energy utilisation., , Between 1950 and 1990, the world’s energy, needs increased four fold. The world’s demand, for electricity has doubled over the last 22 years!, The world’s total primary energy consumption, in 2000 was 9096 million tons of oil. A global, average per capita that works out to be 1.5 tons, of oil. Electricity is at present the fastest growing form of end-use energy worldwide. By 2005, the Asia-Pacific region is expected to surpass, North America in energy consumption and by, 2020 is expected to consume some 40% more, energy than North America., For almost 200 years, coal was the primary energy source fuelling the industrial revolution in, the 19th century. At the close of the 20th century, oil accounted for 39% of the world’s commercial energy consumption, followed by coal, (24%) and natural gas (24%), while nuclear, (7%) and hydro/renewables (6%) accounted for, the rest., Among the commercial energy sources used in, India, coal is a predominant source accounting, for 55% of energy consumption estimated in, 2001, followed by oil (31%), natural gas (8%),, hydro (5%) and nuclear (1%)., In India, biomass (mainly wood and dung) accounts for almost 40% of primary energy supply. While coal continues to remain the dominant fuel for electricity generation, nuclear, power has been increasingly used since the, 1970s and 1980s and the use of natural gas, has increased rapidly in the 80s and 90s., , Environmental Studies for Undergraduate Courses, , 36, , Chapter2.p65, , In 1998, the World Resources Institute found, that the average American uses 24 times the, energy used by an Indian., , 36, , 4/9/2004, 5:07 PM
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Types of energy: There are three main types, of energy; those classified as non-renewable;, those that are said to be renewable; and, nuclear energy, which uses such small quantities of raw material (uranium) that supplies are, to all effect, limitless. However, this classification is inaccurate because several of the renewable sources, if not used ‘sustainably’, can be, depleted more quickly than they can be renewed., , Non renewable energy, To produce electricity from non-renewable resources the material must be ignited. The fuel is, placed in a well contained area and set on fire., The heat generated turns water to steam, which, moves through pipes, to turn the blades of a, turbine. This converts magnetism into electricity, which we use in various appliances., , Non-Renewable Energy Sources: These consist, of the mineral based hydrocarbon fuels coal, oil, and natural gas, that were formed from ancient, prehistoric forests. These are called ‘fossil fuels’, because they are formed after plant life is fossilized. At the present rate of extraction there is, enough coal for a long time to come. Oil and, gas resources however are likely to be used up, within the next 50 years. When these fuels are, burnt, they produce waste products that are, released into the atmosphere as gases such as, carbon dioxide, oxides of sulphur, nitrogen, and, carbon monoxide, all causes of air pollution., These have led to lung problems in an enormous number of people all over the world, and, have also affected buildings like the Taj Mahal, and killed many forests and lakes due to acid, rain. Many of these gases also act like a green, house letting sunlight in and trapping the heat, inside. This is leading to global warming, a raise, in global temperature, increased drought in, some areas, floods in other regions, the melting, of icecaps, and a rise in sea levels, which is slowly, submerging coastal belts all over the world., , Warming the seas also leads to the death of, sensitive organisms such as coral., , Oil and its environmental impacts: India’s oil, reserves which are being used at present lie off, the coast of Mumbai and in Assam. Most of our, natural gas is linked to oil and, because there is, no distribution system, it is just burnt off. This, wastes nearly 40% of available gas. The processes of oil and natural gas drilling, processing, transport and utilisation have serious environmental consequences, such as leaks in which, air and water are polluted and accidental fires, that may go on burning for days or weeks before the fire can be controlled. During refining, oil, solid waste such as salts and grease are produced which also damage the environment. Oil, slicks are caused at sea from offshore oil wells,, cleaning of oil tankers and due to shipwrecks., The most well-known disaster occurred when, the Exxon, Valdez sank, in 1989 and, birds, sea otters, seals,, fish, and, other marine, life, along the, coast, of, Alaska was, seriously affected., Oil powered vehicles emit carbon dioxide, sulphur dioxide, nitrous oxide, carbon monoxide, and particulate matter which is a major cause, of air pollution especially in cities with heavy traffic density. Leaded petrol, leads to neuro damage and reduces attention spans. Running petrol, vehicles with unleaded fuel has been achieved, by adding catalytic converters on all the new, cars, but unleaded fuel contains benzene and, butadene which are known to be carcinogenic, compounds. Delhi, which used to have serious, , Natural Resources, , Chapter2.p65, , 37, , 37, , 4/9/2004, 5:07 PM
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smog problems due to traffic, has been able to, reduce this health hazard by changing a large, number of its vehicles to CNG, which contains, methane., Dependence on dwindling fossil fuel resources,, especially oil, results in political tension, instability and war. At present 65 percent of the, world’s oil reserves are located in the Middle, East., , Coal and its environmental impacts: Coal is, the world’s single largest contributor of green, house gases and is one of the most important, causes of global warming., , CASE STUDY, Oil related disasters, During the Gulf War, oil installations burned, for weeks polluting the air with poisonous, gasses. The fires wasted 5 million barrels of, oil and produced over a million tons of airborne pollutants, including sulphur dioxide,, a major cause of acid rain. The gases moved, to a height of 3km and spread as far as India. Oil also polluted coastlines, killing birds, and fish., , Renewable energy, Many coal-based power generation plants are, not fitted with devices such as electrostatic precipitators to reduce emissions of suspended particulate matter (SPM) which is a major contributor to air pollution. Burning coal also produces, oxides of sulphur and nitrogen which, combined, with water vapour, lead to ‘acid rain’. This kills, forest vegetation, and damages architectural, heritage sites, pollutes water and affects human, health., Thermal power stations that use coal produce, waste in the form of ‘fly ash’. Large dumps are, required to dispose off this waste material, while, efforts have been made to use it for making, bricks. The transport of large quantities of fly, ash and its eventual dumping are costs that have, to be included in calculating the cost-benefits, of thermal power., , Renewable energy systems use resources that, are constantly replaced and are usually less polluting. Examples include hydropower, solar,, wind, and geothermal (energy from the heat, inside the earth). We also get renewable energy from burning trees and even garbage as, fuel and processing other plants into biofuels., One day, all our homes may get their energy, from the sun or the wind. Your car’s gas tank, will use biofuel. Your garbage might contribute, to your city’s energy supply. Renewable energy, technologies will improve the efficiency and cost, of energy systems. We may reach the point, when we may no longer rely mostly on fossil, fuel energy., , CASE STUDY, The Exxon Valdez was wrecked in Prince William Sound in Alaska in 1989 and polluted, large parts of the surrounding seas., , Environmental Studies for Undergraduate Courses, , 38, , Chapter2.p65, , 38, , 4/9/2004, 5:07 PM
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CASE STUDY, , CASE STUDY, , Nearly 50% of the world’s population is dependent on fuel wood as a source of energy. This is obvious in our own country,, which has lost a large proportion of its forest cover as our population expands and, burns enormous amounts of wood. Rural, women, and even women from the lower, economic strata in towns, still have to spend, a large part of their lives collecting fuel wood., To overcome this, various types of fuel-efficient stoves (‘chulas’) can burn wood extremely slowly and do not waste the heat,, and also produce less smoke and ash than, normal ‘chulas’. There have also been several efforts to grow fuelwood by involving, local people in these efforts. Examples include Social Forestry, Farm Forestry and Joint, Forestry Management., , In 1882, the first Hydroelectric power dam, was built in Appleton, Wisconsin. In India the, first hydroelectric power dams were built in, the late 1800s and early 1900s by the Tatas, in the Western Ghats of Maharashtra., Jamshedjee Tata, a great visionary who developed industry in India in the 1800s, wished, to have a clean source of energy to run cotton and textile mills in Bombay as he found, people were getting respiratory infections, due to coal driven mills. He thus asked the, British Government to permit him to develop, dams in the Western Ghats to generate electricity. The four dams are the Andhra,, Shirowata, Valvan and Mulshi hydel dams., An important feature of the Tata power, projects is that they use the high rainfall in, the hills as storage areas. While the rivers, flowing eastwards from the Western Ghats, are dammed in the foothills near the Deccan, plateau, the water is tunneled through the, crest of the Ghats to drop several hundred, meters to the coastal belt. Large turbines in, the power plants generate electricity for, Mumbai and its giant industrial belt., , Hydroelectric Power, This uses water flowing down a natural gradient to turn turbines to generate electricity, known as ‘hydroelectric power’ by constructing, dams across rivers. Between 1950 and 1970,, Hydropower generation worldwide increased, , seven times. The long, life of hydropower, plants, the renewable nature of the, energy source, very, low operating and, maintenance costs,, and absence of inflationary pressures as, in fossil fuels, are, some of its advantages., , Natural Resources, , Chapter2.p65, , 39, , 39, , 4/9/2004, 5:07 PM
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Drawbacks: Although hydroelectric power has, led to economic progress around the world, it, has created serious ecological problems., , CASE STUDY, Narmada Project, , •, , To produce hydroelectric power, large areas of forest and agricultural lands are submerged. These lands traditionally provided, a livelihood for local tribal people and farmers. Conflicts over land use are inevitable., , •, , Silting of the reservoirs (especially as a result of deforestation) reduces the life of the, hydroelectric power installations., , •, , Water is required for many other purposes, besides power generation. These include, domestic requirements, growing agricultural, crops and for industry. This gives rise to, conflicts., , •, , The use of rivers for navigation and fisheries becomes difficult once the water is, dammed for generation of electricity., , •, , Resettlement of displaced persons is a problem for which there is no ready solution., The opposition to many large hydroelectric, schemes is growing as most dam projects, have been unable to resettle people that, were affected and displaced., , •, , In certain regions large dams can induce, seismic activity which will result in earthquakes. There is a great possibility of this, occurring around the Tehri dam in the Himalayan foothills. Shri Sunderlal Bahuguna,, the initiator of the Chipko Movement has, fought against the Tehri Dam for several, years., , With large dams causing social problems, there, has been a trend to develop small hydroelectric, generation units. Multiple small dams have less, impact on the environment. China has the largest number of these - 60,000, generating 13,250, megawatts, i.e. 30% of China’s electricity. Sweden, the US, Italy and France also have developed small dams for electrical power generation. The development of small hydroelectric, power units could become a very important resource in India, which has steeply falling rivers, and the economic capability and technical resources to exploit them., , Solar energy: In one hour, the sun pours as, much energy onto the earth as we use in a whole, year. If it were possible to harness this colossal, quantum of energy, humanity would need no, other source of energy. Today we have developed several methods of collecting this energy, for heating water and generating electricity., , Environmental Studies for Undergraduate Courses, , 40, , Chapter2.p65, , The Narmada Bachao Andolan in India is an, example of a movement against large dams., The gigantic Narmada River Project has affected the livelihoods of hundreds of extremely poor forest dwellers. The rich, landholders downstream from the Sardar, Sarovar dam will derive the maximum economic benefit, whereas the poor tribal, people have lost their homes and traditional, way of life. The dam will also destroy the, livelihood of fishermen at the estuary. The, disastrous impact that this project has on the, lives of the poor, and the way in which they, are being exploited, need to be clearly understood., , 40, , 4/9/2004, 5:07 PM
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Solar heating for homes: Modern housing that, uses air conditioning and/ or heating are extremely energy dependant. A passive solar home, or building is designed to collect the sun’s heat, through large, south-facing glass windows. In, solar heated buildings, sunspaces are built on, the south side of the structure which act as large, heat absorbers. The floors of sunspaces are usually made of tiles or bricks that absorb heat, throughout the day, then release heat at night, when its cold., In energy efficient architecture the sun, water, and wind are used to heat a building when the, weather is cold and to cool it in summer. This is, based on design and building material. Thick, walls of stone or mud were used in traditional, architecture as an insulator. Small doors and, windows kept direct sunlight and heat out., Deeply set glass windows in colonial homes, on, which direct sunlight could not reach, permitted the glass from creating a green house effect. Verandahs also served a similar purpose., Traditional bungalows had high roofs and ventilators that permitted hot air to rise and leave, the room. Cross ventilation where wind can drive, the air in and out of a room keeps it cool. Large, overhangs over windows prevent the glass from, heating the room inside. Double walls are used, to prevent heating. Shady trees around the, house help reduce temperature., , Solar water heating: Most solar water-heating, systems have two main parts: the solar collector and the storage tank. The solar energy collector heats the water, which then flows to a, well insulated storage tank., A common type of collector is the flat-plate collector, a rectangular box with a transparent, cover that faces the sun, usually mounted on, the roof. Small tubes run through the box, carrying the water or other fluid, such as antifreeze,, to be heated. The tubes are mounted on a metal, absorber plate, which is painted black to ab-, , sorb the sun’s heat. The back and sides of the, box are insulated to hold in the heat. Heat builds, up in the collector, and as the fluid passes, through the tubes, it too heats up., Solar water-heating systems cannot heat water, when the sun is not shining. Thus homes must, also have a conventional backup system. About, 80% of homes in Israel have solar hot water, heaters., , Solar cookers: The heat produced by the sun, can be directly used for cooking using solar cookers. A solar cooker is a metal box which is black, on the inside to absorb and retain heat. The lid, has a reflective surface to reflect the heat from, the sun into the box. The box contains black, vessels in which the food to be cooked is placed., India has the world’s largest solar cooker program and an estimated 2 lakh families that use, solar cookers. Although solar cookers reduce the, need for fuel wood and pollution from smoky, wood fires, they have not caught on well in rural areas as they are not suitable to traditional, cooking practices. However, they have great, potential if marketed well., , Other Solar-Powered Devices: Solar desalination, systems (for converting saline or brackish water, into pure distilled water) have been developed., In future, they should become important alternatives for man’s future economic growth in, areas where fresh water is not available., , Photovoltaic energy: The solar technology, which has the greatest potential for use throughout the world is that of solar photo voltaic cells, which directly produce electricity from sunlight, using photovoltaic (PV) (also called solar) cells., Solar cells use the sun’s light, not its heat, to, make electricity. PV cells require little maintenance, have no moving parts, and essentially, no environmental impact. They work cleanly,, , Natural Resources, , Chapter2.p65, , 41, , 41, , 4/9/2004, 5:07 PM
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Photovoltaic Cells, , CASE STUDIES, , safely and silently. They can be installed quickly, in small modules, anywhere there is sunlight., Solar cells are made up of two separate layers, of silicon, each of which contains an electric, charge. When light hits the cells, the charges, begin to move between the two layers and electricity is produced. PV cells are wired together, to form a module. A module of about 40 cells is, enough to power a light bulb. For more power,, PV modules are wired together into an array., PV arrays can produce enough power to meet, the electrical needs of a home. Over the past, few years, extensive work has been done in, decreasing PV technology costs, increasing efficiency, and extending cell lifetimes. Many new, materials, such as amorphous silicon, are being, tested to reduce costs and automate manufacturing., PV cells are commonly used today in calculators, and watches. They also provide power to satellites, electric lights, and small electrical appliances such as radios and for water pumping,, highway lighting, weather stations, and other, electrical systems located away from power lines., Some electric utility companies are building PV, systems into their power supply networks., PV cells are environmentally benign, ie. they do, not release pollutants or toxic material to the, air or water, there is no radioactive substance,, and no catastrophic accidents. Some PV cells,, however, do contain small quantities of toxic, substances such as cadmium and these can be, released to the environment in the event of a, fire. Solar cells are made of silicon which, al-, , In 1981, a plane called ‘The Solar Challenger’ flew from Paris to England in 5, hours, 20 minutes. It had 16,000 solar, cells glued to the wings and tail of the, plane and they produced enough power, to drive a small electric motor and propeller. Since 1987, every three years, there is a World Solar challenge for solar operated vehicles in Australia where, the vehicles cover 3000 kms., , •, , The world’s first solar-powered hospital, is in Mali in Africa. Being situated at the, edge of the Sahara desert, Mali receives, a large amount of sunlight. Panels of, solar cells supply the power needed to, run vital equipment and keep medical, supplies cool in refrigerators., , •, , Space technology required solar energy, and the space race spurred the development of solar cells. Only sunlight can, provide power for long periods of time, for a space station or long distance, spaceship., , •, , Japanese farmers are substituting PV operated insect killers for toxic pesticides., , •, , In recent years, the popularity of building integrated photovoltaics (BIPV’s) has, grown considerably. In this application,, PV devices are designed as part of building materials (i.e. roofs and siding) both, to produce electricity and reduce costs, by replacing the costs of normal construction materials. There are more than, 3,000 BIPV systems in Germany and Japan has a program that will build 70,000, BIPV buildings., , Environmental Studies for Undergraduate Courses, , 42, , Chapter2.p65, , •, , 42, , 4/9/2004, 5:07 PM
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though the second most abundant element in, the earth’s crust, has to be mined. Mining creates environmental problems. PV systems also, of course only work when the sun is shining,, and thus need batteries to store the electricity., , Solar thermal electric power: Solar radiation, can produce high temperatures, which can generate electricity. Areas with low cloud levels of, cover with little scattered radiation as in the, desert are considered most suitable sites. According to a UNDP assessment, STE is about 20, years behind the wind energy market exploitation, but is expected to grow rapidly in the near, future., , Mirror energy: During the 1980s, a major solar, thermal electrical generation unit was built in, California, containing 700 parabolic mirrors,, each with 24 reflectors, 1.5 meters in diameter,, which focused the sun’s energy to produce, steam to generate electricity., , Biomass energy: When a log is burned we are, using biomass energy. Because plants and trees, depend on sunlight to grow, biomass energy is, a form of stored solar energy. Although wood, is the largest source of biomass energy, we also, use agricultural waste, sugarcane wastes, and, other farm byproducts to make energy., There are three ways to use biomass. It can be, burned to produce heat and electricity, changed, to a gas-like fuel such as methane, or changed, to a liquid fuel. Liquid fuels, also called biofuels,, include two forms of alcohol: ethanol and, methanol. Because biomass can be changed, directly into liquid fuel, it could someday supply, much of our transportation fuel needs for cars,, trucks, buses, airplanes and trains with diesel, fuel replaced by ‘biodiesel’ made from vegetable, oils. In the United States, this fuel is now being, produced from soybean oil. Researchers are also, developing algae that produce oils, which can, be converted to biodiesel and new ways have, been found to produce ethanol from grasses,, trees, bark, sawdust, paper, and farming wastes., , Organic municipal solid waste includes paper,, food wastes, and other organic non-fossil-fuel, derived materials such as textiles, natural rubber, and leather that are found in the waste of, urban areas. Currently, in the US, approximately, 31% of organic waste is recovered from municipal solid waste via recycling and composting, programs, 62% is deposited in landfills, and 7%, is incinerated. Waste material can be converted, into electricity by combustion boilers or steam, turbines., Mirror Energy, , Solar thermal systems change sunlight into electricity, by focusing sunlight to boil water to make, steam., , Note that like any fuel, biomass creates some, pollutants, including carbon dioxide, when, burned or converted into energy. In terms of air, pollutants, biomass generate less relative to fossil, fuels. Biomass is naturally low in sulphur and, therefore, when burned, generates low sulphur, dioxide emissions. However, if burned in the, open air, some biomass feedstocks would emit, relatively high levels of nitrous oxides (given the, , Natural Resources, , Chapter2.p65, , 43, , 43, , 4/9/2004, 5:07 PM
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high nitrogen content of plan material), carbon, monoxide, and particulates., , Biogas: Biogas is produced from plant material, and animal waste, garbage, waste from households and some types of industrial wastes, such, as fish processing, dairies, and sewage treatment, plants. It is a mixture of gases which includes, methane, carbon dioxide, hydrogen sulphide, and water vapour. In this mixture, methane, burns easily. With a ton of food waste, one can, produce 85 Cu. M of biogas. Once used, the, residue is used as an agricultural fertilizer., Denmark produces a large quantity of biogas, from waste and produces 15,000 megawatts, of electricity from 15 farmers’ cooperatives. London has a plant which makes 30 megawatts of, electricity a year from 420,000 tons of municipal waste which gives power to 50,000 families. In Germany, 25% of landfills for garbage, produce power from biogas. Japan uses 85%, of its waste and France about 50%., Biogas plants have become increasingly popular in India in the rural sector. The biogas plants, use cowdung, which is converted into a gas, which is used as a fuel. It is also used for running dual fuel engines. The reduction in kitchen, smoke by using biogas has reduced lung conditions in thousands of homes., The fibrous waste of the sugar industry is the, world’s largest potential source of biomass energy. Ethanol produced from sugarcane molasses is a good automobile fuel and is now used, in a third of the vehicles in Brazil., The National Project on Biogas Development, (NPBD), and Community/ Institutional Biogas, Plant Program promote various biogas projects., By 1996 there were already 2.18 million families in India that used biogas. However China, has 20 million households using biogas!, , What you may throw out in your garbage, today could be used as fuel for someone, else. Municipal solid waste has the potential to be a large energy source. Garbage is, an inexpensive energy resource. Unlike, most other energy resources, someone will, collect garbage, deliver it to the power, plant, and even pay to get rid of it. This, helps cover the cost of turning garbage into, energy. Garbage is also a unique resource, because we all contribute to it., Keep a record of all the garbage that you, and our family produce in a day. What proportion of it is in the form of biomass?, Weigh this., How long would it take you to gather, enough waste biomass to make a tankful, (0.85 cu.m.) of biogas? (Remember one ton, of biomass produces 85 cu.m. of biogas), , Wind Power: Wind was the earliest energy, source used for transportation by sailing ships., Some 2000 years ago, windmills were developed, , in China, Afghanistan and Persia to draw water, for irrigation and grinding grain. Most of the, early work on generating electricity from wind, was carried out in Denmark, at the end of the, last century. Today, Denmark and California, have large wind turbine cooperatives which sell, electricity to the government grid. In Tamil Nadu,, there are large wind farms producing 850 megawatts of electricity. At present, India is the third, largest wind energy producer in the world., Environmental Studies for Undergraduate Courses, , 44, , Chapter2.p65, , Activity 5:, , 44, , 4/9/2004, 5:07 PM
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The power in wind is a function of the wind, speed and therefore the average wind speed of, an area is an important determinant of economically feasible power. Wind speed increases with, height. At a given turbine site, the power available 30 meters above ground is typically 60 percent greater than at 10 meters., Over the past two decades, a great deal of technical progress has been made in the design, siting, installation, operation, and maintenance of, power-producing wind mills (turbines). These improvements have led to higher wind conversion, efficiencies and lower electricity production, costs., , Environmental Impacts: Wind power has few environmental impacts, as there are virtually no, air or water emissions, or radiation, or solid, waste production. The principal problems are, bird kills, noise, effect on TV reception, and aesthetic objections to the sheer number of wind, turbines that are required to meet electricity, needs., Although large areas of land are required for, setting up wind farms, the, amount used by the turbine, bases, the foundations and, the access roads is less than, 1% of the total area covered, by the wind farm. The rest, of the area can also be used, for agricultural purposes or, for grazing., , electricity, and requires some other backup or, stand-by electricity source., , Tidal and Wave Power: The earth’s surface is, 70% water. By warming the water, the sun,, creates ocean currents and wind that produces, waves. It is estimated that the solar energy absorbed by the tropical oceans in a week could, equal the entire oil reserves of the world – 1, trillion barrels of oil. The energy of waves in the, sea that crash on the land of all the continents, is estimated at 2 to 3 million megawatts of energy. From the 1970s several countries have, been experimenting with technology to harness, the kinetic energy of the ocean to generate electricity., Tidal power is tapped by placing a barrage across, an estuary and forcing the tidal flow to pass, through turbines. In a one-way system the incoming tide is allowed to fill the basin through, a sluice, and the water so collected is used to, produce electricity during the low tide. In a twoway system power is generated from both the, incoming as well as the outgoing tide., , Siting windmills offshore reduces their demand for land, and visual impact., Wind is an intermittent, source and the intermittency, of wind depends on the geographic distribution of wind., Wind therefore cannot be, used as the sole resource for, Natural Resources, , Chapter2.p65, , 45, , 45, , 4/9/2004, 5:07 PM
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Tidal power stations bring about major ecological changes in the sensitive ecosystem of coastal, regions and can destroy the habitats and nesting places of water birds and interfere with fisheries. A tidal power station at the mouth of a, river blocks the flow of polluted water into the, sea, thereby creating health and pollution hazards in the estuary. Other drawbacks include, offshore energy devices posing navigational, hazards. Residual drift current could affect, spawning of some fish, whose larvae would be, carried away from spawning grounds. They may, also affect the migration patterns of surface, swimming fish., Wave power converts the motion of waves into, electrical or mechanical energy. For this, an energy extraction device is used to drive turbogenerators. Electricity can be generated at sea, and transmitted by cable to land. This energy, source has yet to be fully explored. The largest, concentration of potential wave energy on earth, is located between latitudes 40 to 60 degrees, in both the northern and southern hemispheres,, where the winds blow most strongly., Another developing concept harnesses energy, due to the differences in temperature between, the warm upper layers of the ocean and the, cold deep sea water. These plants are known as, Ocean Thermal Energy Conversion (OTEC). This, is a high tech installation which may prove to, be highly valuable in the future., , Geothermal energy: is the energy stored, within the earth (“geo” for earth and “thermal” for heat). Geothermal energy starts with, hot, molten rock (called magma) deep inside the, earth which surfaces at some parts of the earth’s, crust. The heat rising from the magma warms, underground pools of water known as geothermal reservoirs. If there is an opening, hot underground water comes to the surface and, forms hot springs, or it may boil to form geysers. With modern technology, wells are drilled, , deep below the surface of the earth to tap into, geothermal reservoirs. This is called direct use, of geothermal energy, and it provides a steady, stream of hot water that is pumped to the, earth’s surface., In the 20th century geothermal energy has been, harnessed on a large scale for space heating,, industrial use and electricity production, especially in Iceland, Japan and New Zealand., Geothermal energy is nearly as cheap as hydropower and will thus be increasingly utilised in, future. However, water from geothermal reservoirs often contains minerals that are corrosive, and polluting. Geothermal fluids are a problem, which must be treated before disposal., , Nuclear Power, In 1938 two German scientists Otto Hahn and, Fritz Strassman demonstrated nuclear fission., They found they could split the nucleus of a uranium atom by bombarding it with neutrons. As, the nucleus split, some mass was converted to, energy. The nuclear power industry however, was born in the late 1950s. The first large-scale, nuclear power plant in the world became operational in 1957 in Pennsylvania, US., Dr. Homi Bhabha was the father of Nuclear, Power development in India. The Bhabha Atomic, Environmental Studies for Undergraduate Courses, , 46, , Chapter2.p65, , Geo-Thermal, Energy, , 46, , 4/9/2004, 5:07 PM
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Research Center in Mumbai studies and develops modern nuclear technology. India has 10, nuclear reactors at 5 nuclear power stations that, produce 2% of India’s electricity. These are located in Maharashtra (Tarapur), Rajasthan, Tamil, Nadu, Uttar Pradesh and Gujrat. India has uranium from mines in Bihar. There are deposits of, thorium in Kerala and Tamil Nadu., The nuclear reactors use Uranium 235 to produce electricity. Energy released from 1kg of, Uranium 235 is equivalent to that produced by, burning 3,000 tons of coal. U235 is made into, rods which are fitted into a nuclear reactor. The, control rods absorb neutrons and thus adjust, the fission which releases energy due to the, chain reaction in a reactor unit. The heat energy produced in the reaction is used to heat, water and produce steam, which drives turbines, that produce electricity. The drawback is that, the rods need to be changed periodically. This, has impacts on the environment due to disposal, of nuclear waste. The reaction releases very hot, waste water that damages aquatic ecosystems,, even though it is cooled by a water system before it is released., The disposal of nuclear waste is becoming an, increasingly serious issue. The cost of Nuclear, Power generation must include the high cost of, disposal of its waste and the decommissioning, of old plants. These have high economic as well, as ecological costs that are not taken into account when developing new nuclear installations. For environmental reasons, Sweden has, decided to become a Nuclear Free Country by, 2010., Although the conventional environmental impacts from nuclear power are negligible, what, overshadows all the other types of energy, sources is that an accident can be devastating, and the effects last for long periods of time., While it does not pollute air or water routinely, like oil or biomass, a single accident can kill thousands of people, make many others seriously ill,, , and destroy an area for decades by its radioactivity which leads to death, cancer and genetic, deformities. Land, water, vegetation are destroyed for long periods of time. Management,, storage and disposal of radioactive wastes resulting from nuclear power generation are the, biggest expenses of the nuclear power industry. There have been nuclear accidents at, Chernobyl in USSR and at the Three Mile Island, in USA. The radioactivity unleashed by such an, accident can affect mankind for generations., , Energy Conservation: Conventional energy, sources have a variety of impacts on nature and, human society., India needs to rapidly move into a policy to reduce energy needs and use cleaner energy production technologies. A shift to alternate energy use and renewable energy sources that are, used judiciously and equitably would bring about, environmentally friendly and sustainable, lifestyles. India must reduce its dependency on, imported oil. At present we are under-utilizing, our natural gas resources. We could develop, thousands of mini dams to generate electricity., India wastes great amounts of electricity during, transmission. Fuel wood plantations need to be, enhanced and management through Joint Forestry Management (JFM) has a great promise, for the future., Energy efficient cooking stoves or ‘chulas’ help, the movement of air through it so that the wood, is burnt more efficiently. They also have a chimney to prevent air pollution and thus reduce respiratory problems. While over 2 lakh improved, chulas have been introduced throughout the, country, the number in active use is unknown, as most rural people find it to be unusable for, several reasons. TERI in 1995 estimated that in, India 95% of rural people and 60% of urban, poor still depend on firewood, cattle dung and, crop residue for cooking and other domestic, purposes. Biomass can be converted into biogas, , Natural Resources, , Chapter2.p65, , 47, , 47, , 4/9/2004, 5:07 PM
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or liquid fuels ie. ethanol and methanol. Biogas, digesters convert animal waste or agricultural, residues into gas. This is 60% methane and 40%, CO2 generated by fermentation. The commonly, used agri waste is dung of domestic animals and, rice husk, coconut shells, straw or weeds. The, material left after the gas is used acts as a fertilizer., Small hydrogeneration units are environmentfriendly. They do not displace people, destroy, forests or wildlife habitats or kill aquatic and, terrestrial biodiversity. They can be placed in, several hill streams, on canals or rivers. The generation depends on flowing water due to gravity. However, this fails if the flow is seasonal., It is easy to waste energy but cheaper to save it, than generate it. We can conserve energy by, preventing or reducing waste of energy and by, using resources more efficiently. People waste, energy because government subsidises it. If the, real cost was levied, people would not be able, to afford to waste it carelessly., , Industry and transport are the main growing users of energy in India. Industries that, are known for generating pollution also, waste the most energy. These include chemical industries, especially petrochemical units,, iron and steel, textiles, paper, etc. Unplanned, and inefficient public transport systems, especially in cities, waste large amount of energy. Using bicycles is an excellent method, to reduce the use of energy. In agriculture,, irrigation pumps to lift water are the most, energy intensive agricultural use. These are, either electrical or run on fossil fuels., , Indian industries use more energy than necessary., , Steel and energy: To produce one tonne of, steel, India spends 9.5 million kilocalories. In, Italy it is 4.3 million kilocalories and for Japan it is only 4.1 million kilocalories., Cement industry: Over 2 million kilocalories, are used to produce one tonne of cement in, India. In Germany it is 0.82 million kilocalories, in USA, 0.92 million kilocalories., Vehicles: Lighter materials should be used, for cars. Instead of steel we should use aluminum, fiber glass or plastics. These lighter, materials can reduce the weight by 15 %, and increase the fuel economy by 6 to 8%., Refrigerators: Better technologies reduced, the annual energy needed by a typical Danish 200 liter refrigerator (with no freezer), from 350 kilo Watt hour (kWh) to 90 kWh., Lighting: An 18-watt modern, compact fluorescent lamp, can replace a standard 75-watt, incandescent lamp., , f) Land resources:, Land as a resource: Landforms such as hills,, valleys, plains, river basins and wetlands include, different resource generating areas that the, people living in them depend on. Many traditional farming societies had ways of preserving, areas from which they used resources. Eg. In, the ‘sacred groves’ of the Western Ghats, requests to the spirit of the Grove for permission, to cut a tree, or extract a resource, were accompanied by simple rituals. The outcome of a, chance fall on one side or the other of a stone, Environmental Studies for Undergraduate Courses, , 48, , Chapter2.p65, , CASE STUDIES, , 48, , 4/9/2004, 5:07 PM
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balanced on a rock gave, or withheld permission., The request could not be, repeated for a specified, period., Changes in land use, , If land is utilized carefully, it can be considered a, renewable resource., The roots of trees and, grasses bind the soil. If, forests are depleted, or, grasslands overgrazed,, the land becomes unproductive and wasteland is formed. Intensive, irrigation leads to water logging and salination,, on which crops cannot grow. Land is also converted into a non-renewable resource when, highly toxic industrial and nuclear wastes are, dumped on it., Land on earth is as finite as any of our other, natural resources. While mankind has learnt to, adapt his lifestyle to various ecosystems world, over, he cannot live comfortably for instance on, polar ice caps, on under the sea, or in space in, the foreseeable future., Man needs land for building homes, cultivating, food, maintaining pastures for domestic animals,, developing industries to provide goods, and supporting the industry by creating towns and cities. Equally importantly, man needs to protect, wilderness area in forests, grasslands, wetlands,, mountains, coasts, etc. to protect our vitally, valuable biodiversity., Thus a rational use of land needs careful planning. One can develop most of these different, types of land uses almost anywhere, but Protected Areas (National Park’s and Wildlife Sanctuaries) can only be situated where some of the, natural ecosystems are still undisturbed. These, Protected Areas are important aspects of good, landuse planning., , Land Degradation: Farmland is under threat, due to more and more intense utilisation. Every, year, between 5 to 7 million hectares of land, worldwide is added to the existing degraded, farmland. When soil is used more intensively by, farming, it is eroded more rapidly by wind and, rain. Over irrigating farmland leads to, salinisation, as evaporation of water brings the, salts to the surface of the soil on which crops, cannot grow. Over irrigation also creates water, logging of the topsoil so that crop roots are affected and the crop deteriorates. The use of, more and more chemical fertilizers poisons the, soil so that eventually the land becomes unproductive., As urban centers grow and industrial expansion, occurs, the agricultural land and forests shrink., This is a serious loss and has long term ill effects, on human civilisation., , Soil erosion: The characteristics of natural ecosystems such as forests and grasslands depend, on the type of soil. Soils of various types support a wide variety of crops. The misuse of an, ecosystem leads to loss of valuable soil through, erosion by the monsoon rains and, to a smaller, extent, by wind. The roots of the trees in the, forest hold the soil. Deforestation thus leads to, , Natural Resources, , Chapter2.p65, , 49, , 49, , 4/9/2004, 5:07 PM
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rapid soil erosion. Soil is washed into streams, and is transported into rivers and finally lost to, the sea. The process is more evident in areas, where deforestation has led to erosion on steep, hill slopes as in the Himalayas and in the Western Ghats. These areas are called ‘ecologically, sensitive areas’ or ESAs. To prevent the loss of, millions of tons of valuable soil every year, it is, essential to preserve what remains of our natural forest cover. It is equally important to reforest denuded areas. The linkage between the, existence of forests and the presence of soil is, greater than the forest’s physical soil binding, , CASE STUDY, Selenium – Punjab, In 1981-82, farmers from Hoshirapur and, Nawanshehar Districts approached scientists, of the Punjab Agricultural University (PAU),, Ludhiana, as wheat crops had turned white., Soil analysis indicated selenium (Se) levels in, the area were above toxic limits. Se is a naturally occurring trace element, essential for, animal and human health, but the gap between requirement and excess is narrow., Soils containing 0.5 microgrammes (ug) of, Se per kg or more are injurious to health. In, some areas of Punjab, Se levels ranges from, 0.31 ug/kg to 4.55ug/kg. Rice cultivation, requires the presence of standing water., Being highly soluble, Se dissolves and comes, to the surface. The water then evaporates, leaving the Se behind., , function alone. The soil is enriched by the leaflitter of the forest. This detritus is broken down, by soil micro-organisms, fungi, worms and insects, which help to recycle nutrients in the system. Further losses of our soil wealth will impoverish our country and reduce its capacity to, grow enough food in future., , Until fairly recently mankind acted as if he could, go on for ever exploiting the ecosystems and, natural resources such as soil, water, forests and, grasslands on the Earth’s surface and extracting minerals and fossil fuels from underground., But, in the last few decades, it has become increasingly evident that the global ecosystem has, the capacity to sustain only a limited level of, utilization. Biological systems cannot go on replenishing resources if they are overused or misused. At a critical point, increasing pressure destabilizes their natural balance. Even biological, resources traditionally classified as ‘renewable’, - such as those from our oceans, forests, grasslands and wetlands, are being degraded by overuse and may be permanently destroyed. And, no natural resource is limitless. ‘Non-renewable’, resources will be rapidly exhausted if we continue to use them as intensively as at present., The two most damaging factors leading to the, current rapid depletion of all forms of natural, resources are increasing ‘consumerism’ on the, part of the affluent sections of society, and rapid, population growth. Both factors are the results, of choices we make as individuals. As individuals we need to decide;, •, , What will we leave to our children? (Are, we thinking of short-term or long-term, gain?), , •, , Is my material gain someone else’s loss?, , Greed for material goods has become a way of, life for a majority of people in the developed, world. Population growth and the resulting, shortage of resources most severely affects, people in the developing countries. In nations, such as ours, which are both developing rapidly, and suffering from a population explosion,, both factors are responsible for environmental, degradation. We must ask ourselves if we have, Environmental Studies for Undergraduate Courses, , 50, , Chapter2.p65, , 2.3 ROLE OF AN INDIVIDUAL IN CONSERVATION OF NATURAL RESOURCES, , 50, , 4/9/2004, 5:07 PM
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perhaps reached a critical flash point, at which, economic ‘development’ affects the lives of, people more adversely than the benefits it provides., , What can you do to save electricity?, •, , Turn off lights and fans as soon as you leave, the room., , •, , Use tube lights and energy efficient bulbs, that save energy rather than bulbs. A 40watt tube light gives as much light as a 100, watt bulb., , •, , Keep the bulbs and tubes clean. Dust on, tubes and bulbs decreases lighting levels by, 20 to 30 percent., , •, , Switch off the television or radio as soon as, the program of interest is over., , •, , A pressure cooker can save up to 75 percent of energy required for cooking. It is, also faster., , •, , Keeping the vessel covered with a lid during cooking, helps to cook faster, thus saving energy., , tional levels must be based on the ability to distribute benefits of natural resources by sharing, them more equally among the countries as well, as among communities within countries such, as our own. It is at the local level where people, subsist by the sale of locally collected resources,, that the disparity is greatest. ‘Development’ has, not reached them and they are often unjustly, accused of ‘exploiting’ natural resources. They, must be adequately compensated for the removal of the sources to distant regions and thus, develop a greater stake in protecting natural, resources., There are several principles that each of us can, adopt to bring about sustainable lifestyles. This, primarily comes from caring for our Mother, Earth in all respects. A love and respect for Nature is the greatest sentiment that helps bring, about a feeling for looking at how we use natural resources in a new and sensitive way. Think, of the beauty of a wilderness, a natural forest, in all its magnificence, the expanse of a green, grassland, the clean water of a lake that supports so much life, the crystal clear water of a, hill stream, or the magnificent power of the, oceans, and we cannot help but support the, conservation of nature’s wealth. If we respect, this we cannot commit acts that will deplete, our life supporting systems., , 2.4 EQUITABLE USE OF RESOURCES FOR, SUSTAINABLE LIFESTYLES, Reduction of the unsustainable and unequal use, of resources, and control of our population, growth are essential for the survival of our nation and indeed of human kind everywhere. Our, environment provides us with a variety of goods, and services necessary for our day-to-day lives,, but the soil, water, climate and solar energy, which form the ‘abiotic’ support that we derive, from nature, are in themselves not distributed, evenly throughout the world or within countries., A new economic order at the global and at naNatural Resources, , Chapter2.p65, , 51, , 51, , 4/9/2004, 5:07 PM
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UNIT 3:, , Ecosystems, , 3.1 CONCEPT OF AN ECOSYSTEM, 3.1.1 Understanding ecosystems, 3.1.2 Ecosystem degradation, 3.1.3 Resource utilisation, , 54, 55, 55, 56, , 3.2 STRUCTURE AND FUNCTIONS OF AN ECOSYSTEM, , 56, , 3.3 PRODUCERS, CONSUMERS AND DECOMPOSERS, , 57, , 3.4 ENERGY FLOW IN THE ECOSYSTEM, 3.4.1 The water cycle, 3.4.2 The Carbon cycle, 3.4.3 The Oxygen cycle, 3.4.4 The Nitrogen cycle, 3.4.5 The energy cycle, 3.4.6 Integration of cycles in nature, , 58, 58, 59, 60, 60, 61, 62, , 3.5 ECOLOGICAL SUCCESSION, , 62, , 3.6 FOOD CHAINS, FOOD WEBS AND ECOLOGICAL PYRAMIDS, 3.6.1 The food chains, 3.6.2 The food webs, 3.6.3 The ecological pyramids, , 62, 62, 63, 63, , 3.7 INTRODUCTION, TYPES, CHARACTERISTIC FEATURES, STRUCTURE AND FUNCTIONS 63, 3.7.1 Forest ecosystem, 65, 3.7.2 Grassland ecosystem, 70, 3.7.3 Desert ecosystem, 74, 3.7.4 Aquatic ecosystems (ponds, lakes, streams, rivers, estuaries, oceans), 75, Ecosystems, , Chapter3.p65, , 53, , 53, , 4/9/2004, 5:08 PM
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3.1 CONCEPT OF AN ECOSYSTEM, An ‘Ecosystem’ is a region with a specific and, recognizable landscape form such as forest,, grassland, desert, wetland or coastal area. The, nature of the ecosystem is based on its geographical features such as hills, mountains,, plains, rivers, lakes, coastal areas or islands. It is, also controlled by climatic conditions such as the, amount of sunlight, the temperature and the, rainfall in the region. The geographical, climatic, and soil characteristics form its non-living (abiotic) component. These features create conditions that support a community of plants and, animals that evolution has produced to live in, these specific conditions. The living part of the, ecosystem is referred to as its biotic component., Ecosystems are divided into terrestrial or landbased ecosystems, and aquatic ecosystems in, water. These form the two major habitat conditions for the Earth’s living organisms., All the living organisms in an area live in communities of plants and animals. They interact, with their non-living environment, and with each, other at different points in time for a large number of reasons. Life can exist only in a small proportion of the earth’s land, water and its atmosphere. At a global level the thin skin of the earth, on the land, the sea and the air, forms the biosphere., At a sub-global level, this is divided into biogeographical realms, eg. Eurasia called the, palaeartic realm; South and South-East Asia (of, which India forms a major part) is the Oriental, realm; North America is the Nearctic realm;, South America forms the Neotropical realm;, Africa the Ethiopian realm; and Australia the, Australian realm., At a national or state level, this forms biogeographic regions. There are several distinctive, geographical regions in India- the Himalayas, the, Gangetic Plains, the Highlands of Central India,, , At an even more local level, each area has several structurally and functionally identifiable ecosystems such as different types of forests, grasslands, river catchments, mangrove swamps in, deltas, seashores, islands, etc. to give only a few, examples. Here too each of these forms a habitat for specific plants and animals., Ecosystems have been formed on land and in, the sea by evolution that has created species to, live together in a specific region. Thus ecosystems have both non-living and living components that are typical to an area giving it its own, special characteristics that are easily observed., Definition: The living community of plants and, animals in any area together with the non-living components of the environment such as soil,, air and water, constitute the ecosystem., Some ecosystems are fairly robust and are less, affected by a certain level of human disturbance., Others are highly fragile and are quickly destroyed by human activities. Mountain ecosystems are extremely fragile as degradation of, forest cover leads to severe erosion of soil and, changes in river courses. Island ecosystems are, easily affected by any form of human activity, which can lead to the rapid extinction of several of their unique species of plants and animals. Evergreen forests and coral reefs are also, examples of species rich fragile ecosystems, which must be protected against a variety of, human activities that lead to their degradation., River and wetland ecosystems can be seriously, affected by pollution and changes in surrounding landuse., , Environmental Studies for Undergraduate Courses, , 54, , Chapter3.p65, , the Western and Eastern Ghats, the semi-arid, desert in the West, the Deccan Plateau, the, Coastal Belts, and the Andaman and Nicobar, Islands. These geographically distinctive areas, have plants and animals that have been adapted, to live in each of these regions., , 54, , 4/9/2004, 5:08 PM
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3.1.1 Understanding ecosystems, Natural ecosystems include the forests, grasslands, deserts, and aquatic ecosystems such as, ponds, rivers, lakes, and the sea. Man modified, ecosystems include agricultural land and urban, or industrial land use patterns., Each ecosystem has a set of common features, that can be observed in the field:, •, , ‘What does the ecosystem look like?’, One should be able to describe specific features of the different ecosystems in ones, own surroundings. Field observations must, be made in both urban and natural surroundings., , •, , What is its structure?, Is it a forest, a grassland, a water body, an, agricultural area, a grazing area, an urban, area, an industrial area, etc.?, What you should see are its different characteristics. A forest has layers from the, ground to the canopy. A pond has different types of vegetation from the periphery, to its center. The vegetation on a mountain, changes from its base to its summit., , •, , What is the composition of its plant and, animal species?, List the well-known plants and animals you, can see. Document their abundance and, numbers in nature: very common, common,, uncommon, rare. Wild mammals will not, be seen in large numbers, cattle would be, common. Some birds are common – which, are the most common species? Insect species are very common and most abundant., In fact there are so many that they cannot, be easily counted., , •, , ‘How does the ecosystem work’?, The ecosystem functions through several, biogeochemical cycles and energy transfer, mechanisms. Observe and document the, components of the ecosystem which consists of its non-living or abiotic features such, as air, water, climate and soil. Its biotic components, the various plants and animals., Both these aspects of the ecosystem interact with each other through several functional aspects to form Nature’s ecosystems., Plants, herbivores and carnivores can be, seen to form food chains. All these chains, are joined together to form a ‘web of life’, on which man depends. Each of these use, energy that comes from the sun and powers the ecosystem., , 3.1.2 Ecosystem degradation, Ecosystems are the basis of life itself! The natural ecosystems in the wilderness provide a variety of products and are regions in which a number of vital ecological processes are present,, without which human civilization would not be, able to exist., Ecosystems are however frequently disrupted by, human actions which lead to the extinction of, species of plants and animals that can live only, in the different natural ecosystems. Some species if eliminated seriously affect the ecosystem., These are called ‘keystone’ species. Extinction, occurs due to changes in land use. Forests are, deforested for timber, wetlands are drained to, create more agricultural land and semi arid, grasslands that are used as pastures are changed, into irrigated fields. Pollution from industry and, waste from urban settings can also lead to extinction of several species., The reason for the depletion of natural resources, is twofold – our rapidly exploding population, that needs to sustain itself on resources, and, the growth of affluent societies, which consume, , Ecosystems, , Chapter3.p65, , 55, , 55, , 4/9/2004, 5:08 PM
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and waste a very large proportion of resources, and energy. Increasing extraction of resources, is at the cost of natural ecosystems, leading to a, derangement of their important functions. Each, of us in our daily lives use a variety of resources., If tracked back to their source, one finds that, the resources were originally obtained from, nature and natural ecosystems. Our insensitivity to using resources carefully has produced, societies that nature can no longer sustain. If, one thinks before wasting resources such as water, reusing and recycling paper, using less plastics that are non-degradable, culminatively this, can have positive implications on the integrity, of our natural resource base and conserve the, resources that nature provides., , 3.2 STRUCTURE AND FUNCTIONS OF AN, ECOSYSTEM, Structural aspects, Components that make up the structural aspects of an ecosystem include:, 1) Inorganic aspects – C, N, CO2, H2O., , Ecosystems and man: Every region of our earth, has different ecosystems based on its climatic, conditions and geographical feature. There are, terrestrial ecosystems on land and aquatic ecosystems in water., , 2) Organic compounds – Protein, Carbohydrates, Lipids – link abiotic to biotic, aspects., , 3.1.3 Resource utilisation, , 4) Producers – Plants., , Most traditional societies used their environment, sustainably. Though inequality in resource utilization has existed in every society, the number, of individuals that used a large proportion of, resources was extremely limited. In recent times, the proportion of ‘rich’ people in affluent societies, grew rapidly. Inequality thus became a serious problem. Whereas in the past many resources such as timber and fuel wood from the, forest were extracted sustainably, this pattern, has drastically changed during the last century., The economically better off sections began to, use greater amounts of forest products, while, those people who lived in the forest became, increasingly poor. Similarly the building of large, irrigation projects led to wealth in those areas, that had canals, while those who hand to remain dependent on a constant supply of water, from the river itself, found it difficult to survive., , 5) Macro consumers – Phagotrophs – Large, animals., , 3) Climatic regimes – Temperature, Moisture, Light & Topography., , 6) Micro consumers – Saprotrophs, absorbers – fungi., , Functional aspects, 1) Energy cycles., 2) Food chains., 3) Diversity-interlinkages between organisms., 4) Nutrient cycles-biogeochemical cycles., 5) Evolution., Environmental Studies for Undergraduate Courses, , 56, , Chapter3.p65, , The key to this issue is the need for an ‘equitable’ distribution of all types of natural resources. A more even sharing of resources within, the community can reduce these pressures on, the natural ecosystems., , 56, , 4/9/2004, 5:08 PM
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Since each ecosystem has a non-living and a living part that are linked to each other, one needs, to look around us and observe this closely. This, is an important aspect that is a vital part of our, lives., , producers, Plants are the ‘producers, producers’ in the ecosystem as, they manufacture their food by using energy, from the sun. In the forest these form communities of plant life. In the sea these include tiny, algal forms to large seaweed., , The non-living components of an ecosystem are, the amount of water, the various inorganic substances and organic compounds, and climatic, conditions such as rainfall and temperature,, which depend on geographical conditions and, location which is also related to the amount of, sunlight. The living organisms in an ecosystem, are inseparable from their habitat., , The herbivorous animals are primary consumers as they live on the producers. In a forest,, these are the insects, amphibia, reptiles, birds, and mammals. The herbivorous animals include, for example hare, deer and elephants that live, on plant life. They graze on grass or feed on the, foliage from trees. In grasslands, there are herbivores such as the blackbuck that feed on grass., In the semiarid areas, there are species such as, the chinkara or Indian gazelle. In the sea, there, , The living component of plant life ranges from, extremely small bacteria, which live in air, water and soil, algae which live in fresh and salt, water, to the terrestrial plants which range from, grasses and herbs that grow after the monsoon, every year, to the giant long-lived trees of the, forest. The plants convert energy from sunlight, into organic matter for their growth. They thus, function as producers in the ecosystem. The living component of the animal world ranges from, microscopic animals, to small insects and the, larger animals such as fish, amphibia, reptiles,, birds and mammals. Man is just one of the 1.8, million species of plants and animals that inhabit, the earth., , 3.3 PRODUCERS, CONSUMERS AND DECOMPOSERS, Every living organism is in some way dependent, on other organisms. Plants, Grass, are food for herbivorous animals which are in turn food, for carnivorous animals., Thus there are different, tropic levels in the ecosystem. Some organisms such, as fungi live only on dead, material and inorganic matter., , Herbivores, , Nectarivores, Frugivores, , Gramnivores, , are small fish that live on algae and other plants., At a higher tropic level, there are carnivorous, animals, or secondary, animals, consumers, which live, on herbivorous animals. In our forests,, the carnivorous animals are tigers, leopards, jackals, foxes, and small wild cats. In Carnivores, , Ecosystems, , Chapter3.p65, , 57, , 57, , 4/9/2004, 5:08 PM
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the sea, carnivorous fish live on other fish and, marine animals. Animals that live in the sea, range in size from microscopic forms to giant, mammals such as the whale., , is not widely distributed, it becomes extinct for, all time., , 3.4 ENERGY FLOW IN THE ECOSYSTEM, Decomposers or detrivores are a group of organisms consisting of small animals like worms,, insects, bacteria and fungi, which break down, dead organic material into smaller particles and, finally into simpler substances that are used by, plants as nutrition. Decomposition thus is a vital, function in nature, as without this, all the nutrients would be tied up in dead matter and no, new life could be produced., Most ecosystems are highly complex and consist of an extremely large number of individuals, Detrivores, , of a wide variety of species. In the species-rich, tropical ecosystems (such as in our country), only, a few species are very common, while most species have relatively few individuals. Some species of plants and animals are extremely rare, and may occur only at a few locations. These, are said to be ‘endemic’ to these areas., When human activities alter the balance in these, ecosystems, the “perturbation” leads to the, disappearance of these uncommon species., When this happens to an endemic species that, , All the functions of the ecosystem are in some, way related to the growth and regeneration of, its plant and animal species. These linked processes can be depicted as the various cycles. These processes depend on energy from sunlight., During photosynthesis carbon dioxide is taken up by plants and, oxygen is released. Animals depend on this oxygen for their respiration. The water cycle depends, on the rainfall, which is necessary, for plants and animals to live. The, energy cycle recycles nutrients, into the soil on which plant life, grows. Our own lives are closely, linked to the proper functioning, of these cycles of life. If human, activities go on altering them, humanity cannot, survive on our earth., , 3.4.1 The Water Cycle, When it rains, the water runs along the ground, and flows into rivers or falls directly into the sea., A part of the rainwater that falls on land percolates into the ground. This is stored underground, throughout the rest of the year. Water is drawn, up from the ground by plants along with the, nutrients from the soil. The water is transpired, from the leaves as water vapour and returned, Environmental Studies for Undergraduate Courses, , 58, , Chapter3.p65, , Every ecosystem has several interrelated mechanisms that affect human life. These are the water cycle, the carbon cycle, the oxygen cycle,, the nitrogen cycle and the energy cycle. While, every ecosystem is controlled by these cycles, in, each ecosystem its abiotic and biotic features, are distinct from each other., , 58, , 4/9/2004, 5:08 PM
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3.4.2 The Carbon cycle, Water Cycle, , to the atmosphere. As it is lighter than air, water vapour rises and forms clouds. Winds blow, the clouds for long distances and when the, clouds rise higher, the vapour condenses and, changes into droplets, which fall on the land as, rain. Though this is an endless cycle on which life depends, man’s activities are, making drastic changes in, the atmosphere through, pollution which is altering, rainfall patterns. This is, leading to prolonged, drought periods extending, over years in countries, such as Africa, while causing floods in countries such, as the US. El Nino storms, due to these effects have, devastated many places in, the last few years., , The carbon, which occurs in, organic compounds, is included in both the abiotic and, biotic parts of the ecosystem., Carbon is a building block of, both plant and animal tissues., In the atmosphere, carbon, occurs as carbon dioxide, (CO2). In the presence of sunlight, plants take up carbon, dioxide from the atmosphere, through their leaves. The, plants combine carbon dioxide with water, which is absorbed by their roots from the, soil. In the presence of sunlight they are able to form carbohydrates that contain carbon. This process is known as, photosynthesis. Plants use this, complex mechanism for their, growth and development. In, this process, plants release, oxygen into the atmosphere on which animals, depend for their respiration. Plants therefore, help in regulating and monitoring the percentage of Oxygen and Carbon dioxide in the earth’s, atmosphere. All of mankind thus depends on, , Carbon Cycle, , Ecosystems, , Chapter3.p65, , 59, , 59, , 4/9/2004, 5:08 PM
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the oxygen generated through this cycle. It also, keeps the CO2 at acceptable levels., Herbivorous animals feed on plant material,, which is used by them for energy and for their, growth. Both plants and animals release carbon, dioxide during respiration. They also return fixed, carbon to the soil in the waste they excrete., When plants and animals die they return their, carbon to the soil. These processes complete the, carbon cycle., , Oxygen Cycle, , >, , >, , 3.4.4 The Nitrogen Cycle, Carnivorous animals feed on herbivorous animals that live on plants. When animals defecate,, this waste material is broken down by worms, and insects mostly beetles and ants. These small, ‘soil animals’ break the waste material into, smaller bits on which microscopic bacteria and, fungi can act. This material is thus broken down, further into nutrients that plants can absorb and, use for their growth. Thus nutrients are recycled, back from animals to plants. Similarly the bodies of dead animals are also broken down into, nutrients that are used by the, plants for their growth. Thus, the nitrogen cycle on which, life is dependent is completed., , >, , Nitrogen fixing bacteria and, fungi in soil gives this important element to plants, which, absorb it as nitrates. The nitrates are a part of the plant’s, metabolism, which help in, forming new plant proteins., This is used by animals that, feed on the plants. The nitrogen is then transferred to carnivorous animals when they, feed on the herbivores. Thus our own lives are, , 3.4.3 The Oxygen Cycle, , >, , Nitrogen, Cycle, , >, >, , Environmental Studies for Undergraduate Courses, , 60, , Chapter3.p65, , >, , >, , Oxygen is taken up by plants and animals from the air during respiration., The plants return oxygen to the atmosphere during photosynthesis. This, links the Oxygen Cycle to the Carbon, Cycle. Deforestation is likely to gradually reduce the oxygen levels in our, atmosphere. Thus plant life plays an, important role in our lives which we, frequently do not appreciate. This is, an important reason to participate in, afforestation programs., , 60, , 4/9/2004, 5:08 PM
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closely interlinked to soil animals, fungi and even, bacteria in the soil. When we think of food webs,, we usually think of the large mammals and other, large forms of life. But we need to understand, that it is the unseen small animals, plants and, microscopic forms of life that are of great value, for the functioning of the ecosystem., , 3.4.5 The Energy Cycle, The energy cycle is based on the flow of energy, through the ecosystem. Energy from sunlight is, converted by plants themselves into growing, new plant material which includes leaves, flowers, fruit, branches, trunks and roots of plants., , Since plants can grow by converting the sun’s, energy directly into their tissues, they are known, as producers in the ecosystem. The plants are, used by herbivorous animals as food, which, gives them energy. A large part of this energy is, used up for day to day functions of these animals such as breathing, digesting food, supporting growth of tissues, maintaining blood flow, and body temperature. Energy is also used for, activities such as looking for food, finding shelter, breeding and bringing up young ones. The, carnivores in turn depend on herbivorous animals on which they feed. Thus the different plant, and animal species are linked to one another, through food chains, chains. Each food chain has three, or four links. However as each plant or animal, can be linked to several other plants or, animals through many different linkages, these inter-linked chains can be, depicted as a complex food web, web. This, is thus called the ‘web of life’ that shows, that there are thousands of interrelationships in nature., The energy in the ecosystem can be depicted in the form of a food pyramid or, energy pyramid, pyramid. The food pyramid has, produca large base of plants called ‘producers, ers’. The pyramid has a narrower middle, section that depicts the number and biomass of herbivorous animals, animals, which are, first order consumers, called ‘first, consumers’. The apex, depicts the small biomass of carnivorous, animals called ‘second, second order consumers, ers’. Man is one of the animals at the, apex of the pyramid. Thus to support, mankind, there must be a large base of, herbivorous animals and an even greater, quantity of plant material., When plants and animals die, this material is returned to the soil after being, broken down into simpler substances by, decomposers such as insects, worms,, bacteria and fungi so that plants can, absorb the nutrients through their roots., , Energy Cycle, , Ecosystems, , Chapter3.p65, , 61, , 61, , 4/9/2004, 5:08 PM
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Animals excrete waste products after digesting, food, which goes back to the soil. This links the, energy cycle to the Nitrogen cycle., , 3.4.6 Integration of cycles in Nature, These cycles are a part of global life processes., These biogeochcemical cycles have specific features in each of the ecosystems. These cycles, are however linked to those of adjacent ecosystems. Their characteristics are specific to the, plant and animal communities in the region. This, is related to the geographical features of the, area, the climate and the chemical composition, of the soil. Together the cycles are responsible, for maintaining life on earth. If mankind disturbs, these cycles beyond the limits that nature can, sustain, they will eventually break down and lead, to a degraded earth on which man will not be, able to survive., , 3.5 ECOLOGICAL SUCCESSION, Ecological succession is a process through which, ecosystems tend to change over a period of time., Succession can be related to seasonal environmental changes, which create changes in the, community of plants and animals living in the, ecosystem. Other successional events may take, much longer periods of time extending to several decades. If a forest is cleared, it is initially, colonized by a certain group of species of plants, and animals, which gradually change through, an orderly process of community development., One can predict that an opened up area will, gradually be converted into a grassland, a, shrubland and finally a woodland and a forest if, permitted to do so without human interference., There is a tendency for succession to produce a, more or less stable state at the end of the successional stages. Developmental stages in the, ecosystem thus consist of a pioneer stage, a, series of changes known as serel stages, and, finally a climax stage. The successive stages are, , 3.6 FOOD CHAINS, FOOD WEBS AND ECOLOGICAL PYRAMIDS, The transfer of energy from the source in plants, through a series of organisms by eating and, being eaten constitutes food chains. At each, transfer, a large proportion of energy is lost in, the form of heat. These food chains are not isolated sequences, but are interconnected with, each other. This interlocking pattern is known, as the food web. Each step of the food web is, called a trophic level. Hence green plants occupy the first level, herbivores the second level,, carnivores the third level and secondary carnivores the fourth level. These trophic levels together form the ecological pyramid., , 3.6.1 The food chains, The most obvious aspect of nature is that energy must pass from one living organism to another. When herbivorous animals feed on plants,, energy is transferred from plants to animals. In, an ecosystem, some of the animals feed on other, living organisms, while some feed on dead organic matter. The latter form the ‘detritus’ food, chain. At each linkage in the chain, a major part, of the energy from the food is lost for daily activities. Each chain usually has only four to five, such links. However a single species may be, linked to a large number of species., , Environmental Studies for Undergraduate Courses, , 62, , Chapter3.p65, , related to the way in which energy flows, through the biological system. The most frequent example of successional changes occur, in a pond ecosystem where it fluctuates from a, dry terrestrial habitat to the early colonisation, stage by small aquatic species after the monsoon, which gradually passes through to a mature aquatic ecosystem, and then reverts back, to its dry stage in summer where its aquatic life, remains dormant., , 62, , 4/9/2004, 5:08 PM
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3.6.2 The food webs, , Aquatic, Food Pyramid, , In an ecosystem there are a very large number, of interlinked chains. This forms a food web. If, the linkages in the chains that make up the web, of life are disrupted due to human activities that, lead to the loss or extinction of species, the web, breaks down., , 3.6.3 The ecological pyramids, In an ecosystem, green plants – the producers,, utilize energy directly from sunlight and convert, it into matter. A large number of these organisms form the most basic, or first ‘trophic level’, of the food pyramid. The herbivorous animals, that eat plants are at the second trophic level, , and are called primary consumers. The predators that feed on them form the third trophic, level and are known as secondary consumers., Only a few animals form the third trophic level, consisting of carnivores at the apex of the food, pyramid. This is how energy is used by living, creatures and flows through the ecosystem from, its base to the apex. Much of the energy is used, up in activities of each living organism., , Terrestrial, Food Pyramid, , 3.7 INTRODUCTION, TYPES, CHARACTERISTIC FEATURES, STRUCTURE AND FUNCTIONS, Types of Ecosystems, Terrestrial Ecosystems, , Aquatic Ecosystems, , Forest, , Pond, , Grassland, , Lake, , Semi arid areas, , Wetland, , Deserts, , River, , Mountains, , Delta, , Islands, , Marine, , Ecosystems, , Chapter3.p65, , 63, , 63, , 4/9/2004, 5:08 PM
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For each of these ecosystems we need to understand 4 basic issues:, 1. What is the nature of the ecosystem? What, is its structure and its functions?, 2. Who uses the ecosystem and for what purpose?, 3. How are these ecosystems degraded?, 4. What can be done to protect it from deteriorating in the long-term? How can the ecosystem be conserved?, , Ecosystem goods and services, Direct Values:, These are resources that people depend upon, directly and are easy to quantify in economic, terms., •, , Consumptive Use Value - Non-market, value of fruit, fodder, firewood, etc., that are used by people who collect, them from their surrounds.], , •, , Productive Use Value - Commercial, value of timber, fish, medicinal plants,, etc. that people collect for sale., , Indirect Values:, These are uses that do not have easy ways to, quantify them in terms of a clearly definable, price., •, , Non-consumptive use value - scientific, research, bird-watching, ecotourism,, etc., , •, , Option value - maintaining options for, the future, so that by preserving them, one could reap economic benefits in the, future., , Existence value - ethical and emotional, aspects of the existence of wildlife and, nature., , Terrestrial ecosystems in their natural state are, found in different types of forests, grasslands,, semiarid areas, deserts and sea coasts. Where, the land is intensively used, these have been, gradually modified over several thousand years, into agricultural and pastoral regions. In the recent past they have been rapidly converted into, intensively irrigated agricultural ecosystems or, into urban and industrial centers. Though this, has increased production of food and provides the raw material for ‘consumer’ goods, that we use, the overuse and misuse of land, and natural ecosystems has led to a serious, degradation of our environment. The unsustainable use of environmental goods such as soil,, water, fuelwood, timber from forest, grasses, and herbs from grasslands for grazing and repeatedly burning the grass, degrades these natural ecosystems. Similarly, improper use of resources can destroy the services that the natural ecosystems provide. These processes of nature such as photosynthesis, climate control, prevention of soil erosion are disturbed by many, human activities. When our human population, was small, most ecosystems could supply all our, sustainably’., needs. Resources were thus used ‘sustainably’., As industrial ‘development’ led to a very great, increase in consumption of resources, the short, term economic gains for people became an indicator of progress, rather than long term ecounsuslogical benefits. This has resulted in an ‘unsustainable use’ of natural resources. Forests thus, disappear, rivers run dry, deserts begin to spread,, and air, water and soil become increasingly polluted as by-products of development. Human, well being itself is then seriously affected., , Environmental Studies for Undergraduate Courses, , 64, , Chapter3.p65, , •, , 64, , 4/9/2004, 5:08 PM
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3.7.1 Forest ecosystem, Forests are formed by a community of plants, which is predominantly structurally defined by, its trees, shrubs, climbers and ground cover., Natural vegetation looks vastly different from a, group of planted trees, which are in orderly, rows. The most ‘natural’ undisturbed forests are, located mainly in our National Parks and Wildlife Sanctuaries. The landscapes that make up, various types of forests look very different from, each other. Their distinctive appearance is a fascinating aspect of nature. Each forest type forms, a habitat for a specific community of animals, that are adapted to live in it., , What is a forest ecosystem?, The forest ecosystem has two parts:, •, , •, , The non-living or abiotic aspects of the, forest: The type of forest depends upon the, abiotic conditions at the site. Forests on, mountains and hills differ from those along, river valleys. Vegetation is specific to the, amount of rainfall and the local temperature which varies according to latitude and, altitude. Forests also vary in their plant communities in response to the type of soil., The living or the biotic aspects of the forest: The plants and animals form communities that are specific to each forest type., For instance coniferous trees occur in the, Himalayas. Mangrove trees occur in river, deltas. Thorn trees grow in arid areas. The, snow leopard lives in the Himalayas while, the leopard and tiger live in the forests of, the rest of India. Wild sheep and goats live, high up in the Himalayas. Many of the birds, of the Himalayan forests are different from, the rest of India. Evergreen forests of the, Western Ghats and North East India are, most rich in plant and animal species., , The biotic component includes both the large, (macrophytes) and the microscopic plants and, animals., Plants include the trees, shrubs, climbers,, grasses, and herbs in the forest. These include, species that flower (angiosperms), and non-flowering species (gymnosperms) such as ferns, bryophytes, fungi and algae., The animals include species of mammals, birds,, reptiles, amphibians, fish, insects and other invertebrates and a variety of microscopic animals., As the plant and animal species are closely dependent on each other, together they form different types of forest communities. Man is a part, of these forest ecosystems and the local people, depend directly on the forest for several natural, resources that act as their life support systems., People who do not live in the forest buy forest, products such as wood and paper, which has, been extracted from the forest. Thus they use, forest produce indirectly from the market., Forest types in India: The forest type depends, upon the abiotic factors such as climate and soil, characteristics of a region. Forests in India can, be broadly divided into Coniferous forests and, Broadleaved forests., They can also be classified according to the nature of their tree species – evergreen, deciduous, xerophytic or thorn trees, mangroves, etc., They can also be classified according to the most, abundant species of trees such as Sal or Teak, forests. In many cases a forest is named after, the first three or four most abundant tree species., , Coniferous forests grow in the Himalayan mountain region, where the temperatures are low., These forests have tall stately trees with needlelike leaves and downward sloping branches so, that the snow can slip off the branches. They, , Ecosystems, , Chapter3.p65, , 65, , 65, , 4/9/2004, 5:08 PM
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eral months. Some even get two, monsoons, such as in Southern India. Evergreen plants shed a few of, their leaves throughout the year., There is no dry leafless phase as in a, deciduous forest. An evergreen forest thus looks green throughout the, year. The trees overlap with each, other to form a continuous canopy., Thus very little light penetrates down, to the forest floor. Only a few shade, loving plants can grow in the ground, layer in areas where some light filters down from the closed canopy., The forest is rich in orchids and ferns., The barks of the trees are covered, in moss. The forest abounds in animal life and is most rich in insect life., , Coniferous forest, , Evergreen forest, , Broadleaved forest, , have cones instead of seeds and are, called gymnosperms., , Broadleaved forests have several types,, such as evergreen forests, deciduous, forests, thorn forests, and mangrove, forests. Broadleaved forests have large, leaves of various shapes., Evergreen forests grow in the high rainfall areas of the Western Ghats, North, Eastern India and the Andaman and, Nicobar Islands. These forests grow in, areas where the monsoon lasts for sevEnvironmental Studies for Undergraduate Courses, , 66, , Chapter3.p65, , 66, , 4/9/2004, 5:08 PM
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Deciduous forest, , Thorn forest, , called xerophytic species and are, able to conserve water. Some of, these trees have small leaves,, while other species have thick,, waxy leaves to reduce water, losses during transpiration. Thorn, forest trees have long or fibrous, roots to reach water at great, depths. Many of these plants, have thorns, which reduce water loss and protect them from, herbivores., , Mangrove forests grow along the, coast especially in the river deltas. These plants are able to grow, , Deciduous forests are found in regions, with a moderate amount of seasonal, rainfall that lasts for only a few months., Most of the forests in which Teak trees, grow are of this type. The deciduous, trees shed their leaves during the winter and hot summer months. In March, or April they regain their fresh leaves just, before the monsoon, when they grow, vigorously in response to the rains. Thus, there are periods of leaf fall and canopy, regrowth. The forest frequently has a, thick undergrowth as light can penetrate, easily onto the forest floor., , Mangrove, , Thorn forests are found in the semi- arid, regions of India. The trees, which are, sparsely distributed, are surrounded by, open grassy areas. Thorny plants are, Ecosystems, , Chapter3.p65, , 67, , 67, , 4/9/2004, 5:08 PM
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Forest communities:, Forest type, , Plants Examples, , Common Animal Examples, , Rare Animal Examples, , Himalayan Coniferous, , Pine, deodar, , Wild goats and sheep,, Himalayan black bear., , Himalayan Broadleaved, , Maple, oak, , Snow leopard, Hangul,, Himalayan brown bear,, Musk deer, Himalayan, Wolf., , Evergreen North-east,, Western Ghats,, Andaman & Nicobar, , Jamun, Ficus,, Dipterocarpus, , Tiger, Leopard, Sambar, Malabar, whistling thrush, Malabar Pied, hornbill, tree frogs., , Pigmy Hog, Rhino,, Liontailed macaque, , Deciduous – Dry, , Teak, Ain,, Terminalia, , Tiger, Chital, Barking deer,, Babblers, Flycatchers, Hornbills., , Moist, , Sal, , Thorn and scrub,, Semiarid forests, , Babul, Ber, Neem, , Blackbuck, Chinkara, Fourhorned, antelope, Partridge, Monitor, lizard., , Wolf, Bustard, Florican,, Bustards,, , Mangrove Delta, Forests, , Avicenia, , Crocodile, shorebirds – sandpipers,, plovers, fish, crustacea., , Water monitor lizard., , in a mix of saline and fresh water. They grow, luxuriantly in muddy areas covered with silt that, the rivers have brought down. The mangrove, trees have breathing roots that emerge from, the mudbanks., , Forest utilisation: Natural forests provide local, people with a variety of products if the forest is, used carefully. Over-exploitation for fuel wood, or timber, and conversion to monoculture plantations for timber or other products, impoverishes local people as the economic benefit goes, to people who live elsewhere. The entire resource base on which local people have traditionally survived for generations, is rapidly destroyed. Eventually the forest is completely degraded., Natural forest ecosystems play an important role, in controlling local climate and water regimes., It is well-known that under the canopy of a natural forest, it is cooler than outside the forest., , Forest products that are collected by people, include food such as fruit, roots, herbs and medicinal plants. People depend on fuelwood to, cook food, collect fodder for domestic animals,, cut building material for housing, collect, medicinal plants that have been known for, generations for several ailments and use a variety of non timer forest products such as fiber,, cane, gum, to make household articles. Wood, from different species of trees have special uses., For instance a soft wood is used for the yok of a, bullock cart while a very hard wood is used for, its axil. These forest products are of great ecoEnvironmental Studies for Undergraduate Courses, , 68, , Chapter3.p65, , During the monsoon, the forest retains moisture and slowly releases it through perennial, streams during the rest of the year. Plantations, fail to perform this function adequately. The loss, of forest cover in the catchments of a river thus, leads to irreversible changes such as excessive, soil erosion, large run-off of surface water during monsoons leading to flash floods, and a, shortage of water once the monsoons are over., , 68, , 4/9/2004, 5:08 PM
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are more resistant to diseases. New industrial, products are being produced from the wild, plants of the forest. Many of our new medicines come from wild plants., , Forest Products, , Direct uses of forest products, Fruits – mango, jamun, awla, Roots – Dioscoria, Medicine – Gloriosa, Foxglove, Fuelwood – many species of trees and shrubs, Small timber for building huts and houses, nomic value as they are collected, sold and marketed. Forest dwellers and agricultural people, use these goods directly. Other people get them, indirectly from the market. Traditional types of, agriculture needs forest material such as, branches and leaves, which are burnt to form, wood ash which acts as a fertiliser for crops such, as rice., Urban people use these forest resources indirectly as all their food and other goods come, from agricultural areas that are dependent on, the neighbouring forests., Forest services include the control of the flow, of water in streams and rivers. Forest cover reduces surface runoff of rainwater and allows, ground water to be stored. Forests prevent erosion of soil. Once soil is lost by erosion, it can, take thousands of years to reform. Forests regulate local temperature. It is cooler and more, moist under the shade of the trees in the forest., Most importantly, forests absorb carbon dioxide and release oxygen that we breathe., The wild relatives of our crop plants and fruit, trees have special characteristics in their genes, which are used to develop new crops and newer, varieties of fruit. These newer varieties developed from wild relatives give greater yields or, , Wood for farm implements, Bamboo and cane for baskets, Grass for grazing and stall feeding livestock, , Indirect uses of forest products, Building material for construction and furniture for the urban sector, Medicinal products collected and processed, into drugs, Gums and resins processed into a variety of, products, Raw material for industrial products and, chemicals, Paper from bamboo and softwoods, , What are the threats to the forest ecosystem?, As forests grow very slowly, we cannot use more, resources than they can produce during a growing season. If timber is felled beyond a certain, limit the forest cannot regenerate. The gaps in, the forest change the habitat quality for its animals. The more sensitive species cannot survive, under these changed conditions. Overutilizing, , Ecosystems, , Chapter3.p65, , 69, , 69, , 4/9/2004, 5:08 PM
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forest resources is an unsustainable way of misusing our limited forest resources. We are now, creating more and more goods that are manufactured from raw material from the forest. This, leads to forest degradation and finally changes, the ecosystem into wasteland. Wood is illegally, extracted from many forests leading to a highly, disturbed ecosystem., Developmental activities such as rapid population growth together with, urbanisation,, industrialisation and the increasing use of consumer goods, leads to over utilisation of forest, produce. Forests are shrinking as our need for, agricultural land increases. It is estimated that, India’s forest cover has decreased from about, 33% to 11% in the last century. The increasing, use of wood for timber, wood pulp for paper, and the extensive use of fuelwood results in, continual forest loss. Forests are also lost by, mining and building dams. As the forest resources are exploited beyond what they can produce the forest canopy is opened up, the ecosystem is degraded, and its wildlife is seriously, threatened. As the forest is fragmented into, small patches its wild plant and animal species, become extinct. These can never be brought, back. Extinction is forever., , What if the forests disappear?, When forests are cut down tribal people who, depend directly on them for food and fuelwood, and other products find it very difficult to survive. Agricultural people do not get enough, fuelwood, small timber, etc. for making houses, and farm implements. Urban people who depend on food from agricultural areas, which in, turn depend on neighbouring forest ecosystems, have to pay a higher price for food as human, population grows., Insects that live and breed in the forest such as, bees, butterflies and moths decrease in abundance once forests are degraded. As their numbers decrease they are unable to effectively pol-, , The rain that falls on deforested land flows directly into nearby rivers. Thus water is not retained under the ground. People thus do not, get a sufficient quantity of water throughout, the year. The exposed soil is rapidly washed away, during the rains once the protective forest cover, is removed. Thus agriculture is seriously affected, in such areas. In deforested areas, the water in, streams is brown in colour as soil is washed away, while water in forested streams is crystal clear., Wild animals lose their habitat. This leads to, extinction of our precious species. Residual forests must be protected from being destroyed, any further if all the diverse species of plants, and animals are to be kept for future generations., , How can forest ecosystems be conserved?, We can conserve forests only if we use its resources carefully. This can be done by using alternate sources of energy instead of fuelwood., There is a need to grow more trees than are cut, down from forests every year for timber. Afforestation needs to be done continuously from, which fuelwood and timber can be judiciously, used., The natural forests with all their diverse species, must be protected as National Parks and Wildlife Sanctuaries where all the plants and animals, can be preserved., , 3.7.2 Grassland ecosystems, A wide range of landscapes in which the vegetation is mainly formed by grasses and small, annual plants are adapted to India’s various climatic conditions. These form a variety of grassland ecosystems with their specific plants and, animals., Environmental Studies for Undergraduate Courses, , 70, , Chapter3.p65, , linate agricultural crops and fruit trees. This leads, to a decrease in agricultural yields., , 70, , 4/9/2004, 5:08 PM
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What is a grassland ecosystem?, Grasslands cover areas where rainfall is usually, low and/or the soil depth and quality is poor., The low rainfall prevents the growth of a large, number of trees and shrubs, but is sufficient to, support the growth of grass cover during the, monsoon. Many of the grasses and other small, herbs become dry and the part above the, ground dies during the summer months. In the, next monsoon the grass cover grows back from, the root stock and the seeds of the previous, year. This change gives grasslands a highly seasonal appearance with periods of increased, growth followed by a dormant phase., A variety of grasses, herbs, and several species, of insects, birds and mammals have evolved so, that they are adapted to these wide-open grass, covered areas. These animals are able to live in, conditions where food is plentiful after the rains,, so that they can store this as fat that they use, during the dry period when there is very little to, eat. Man began to use these grasslands as pastures to feed his livestock when he began to, domesticate animals and became a pastoralist, in ancient times., Grassland Types in India: Grasslands form a, variety of ecosystems that are located in different climatic conditions ranging from near desert, conditions, to patches of shola grasslands that, occur on hillslopes alongside the extremely moist, evergreen forests in South India. In the Himalayan mountains there are the high cold Himalayan pastures. There are tracts of tall elephant, grass in the low-lying Terai belt south of the, Himalayan foothills. There are semi-arid grasslands in Western India, parts of Central India,, and in the Deccan Plateau., The Himalayan pasture belt extends upto the, snowline. The grasslands at a lower level form, patches along with coniferous or broadleaved, forests. Himalayan wildlife require both the forest and the grassland ecosystem as important, parts of their habitat. The animals migrate up, , Himalayan Pastures, , into the high altitude grasslands in summer and, move down into the forest in winter when the, snow covers the grassland. These Himalayan, pastures have a large variety of grasses and, herbs. Himalayan hill slopes are covered with, thousands of colourful flowering plants. There, are also a large number of medicinal plants., The Terai consists of patches of tall grasslands, interspersed with a Sal forest ecosystem. The, patches of tall elephant grass, which grows to a, height of about five meters, are located in the, low-lying waterlogged areas. The Sal forest, patches cover the elevated regions and the Himalayan foothills. The Terai also includes, marshes in low-lying depressions. This ecosystem extends as a belt south of the Himalayan, foothills., , Terai grassland, , Ecosystems, , Chapter3.p65, , 71, , 71, , 4/9/2004, 5:08 PM
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Semiarid grassland, , patches of forest that occur along the streams, and in depressions. The grasslands are related, to repeated fires that do not permit the forest, to grow., The grasses are the major producers of biomass, in these regions. Each grassland ecosystem has, a wide variety of species of grasses and herbs., Some grass and herb species are more sensitive, to excessive grazing and are suppressed if the, area is over grazed. Others are destroyed by repeated fires and cannot regenerate. Thus overused or frequently burnt grasslands are degraded and are poor in plant species diversity., , The Semi-arid plains of Western India, Central India and the Deccan are covered by grassland tracts with patches of thorn forest. Several, mammals such as the wolf, the blackbuck, the, chinkara, and birds such as the bustards and, floricans are adapted to these arid conditions., The Scrublands of the Deccan Plateau are covered with seasonal grasses and herbs on which, its fauna is dependent. It is teaming with insect, life on which the insectivorous birds feed., Shola grassland, , The Shola grasslands consist of patches on, hillslopes along with the Shola forests on the, Western Ghats, Nilgiri and Annamalai ranges., This forms a patchwork of grassland on the, slopes and forest habitats along the streams and, lowlying areas., Grasslands are not restricted only to low rainfall, areas. Certain grassland types form when clearings are made in different forest types. Some, are located on the higher steep hill slopes with, , Overgrazing by huge herds of domestic livestock, has degraded many grasslands. Grasslands have, diverse species of insects that pollinate crops., There are also predators of these insects such, as the small mammals like shrews, reptiles like, lizards, birds of prey, and amphibia such as frogs, and toads. All these carnivorous animals help to, control insect pests in adjoining agricultural, lands., , What are the threats to grassland ecosystems?, In many areas grasslands have been used for, centuries by pastoral communities., Overutilization and changes in landuse of the, Environmental Studies for Undergraduate Courses, , 72, , Chapter3.p65, , How are grasslands used?, Grasslands are the grazing areas of many rural, communities. Farmers who keep cattle or goats,, as well as shepherds who keep sheep, are highly, dependent on grasslands. Domestic animals are, grazed in the ‘common’ land of the village. Fodder is collected and stored to feed cattle when, there is no grass left for them to graze in summer. Grass is also used to thatch houses and, farm sheds. The thorny bushes and branches of, the few trees that are seen in grasslands are, used as a major source of fuelwood., , 72, , 4/9/2004, 5:08 PM
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‘common grazing lands’ of rural communities, has lead to their degradation. The grassland, cover in the country in terms of permanent pastures now covers only 3.7 percent of land. A, major threat to natural grasslands is the conversion of grasslands into irrigated farmlands., In the Deccan, grasslands have been altered to, irrigated farms and are now mainly used to grow, sugarcane. After continuous irrigation such land, becomes saline and useless in a few years. More, recently many of these residual grassland tracts, have been converted into industrial areas. This, provides short-term economic gains but result, in long-term economic and ecological losses., Grasslands have a limited ability to support domestic animals and wildlife. Increasing this pressure by increasing the number of domestic animals reduces the ‘naturalness’ of the grassland, ecosystem leading to its degradation., Most grassland ecosystems are highly modified, by human activities. Cattle, sheep and goat grazing, and lighting repeated fires affects grasslands, adversely. Changing the grasslands to other, forms of landuse such as agriculture, tree plantations and industrialisation forms a serious, threat to this highly productive ecosystem. Thus, some of the grassland patches which are in a, less disturbed state and have retained their special plants and animals need to be urgently protected., Degradation of grasslands due to over grazing, by cattle, sheep and goats occurs if more than, a critical number of domestic animals are present, in the grasslands. When animals overgraze the, area, the grasses are converted into flat stubs, with very little green matter. Degraded grasslands have fewer grass species as the nutritious, species are entirely used up by the large number of domestic animals. They are thus unable, to regenerate., When fires are lit in the grasslands in summer,, the burnt grass gets a fresh flush of small green, , shoots which the domestic animals graze on. If, this is done too frequently the grasslands begin, to deteriorate. Finally grasslands become bare,, the soil is solidly compacted by trampling, or is, washed away during the monsoon by rain and, whipped into dust storms during the hot dry, summer. The land is degraded, as there is no, grass to hold the soil in place. It becomes a, wasteland., , Why are our grassland species vanishing?, Most people feel that it is only our forests and, its wildlife that is disappearing. However, other, natural ecosystems such as grasslands are disappearing even more rapidly., Many of the grassland species have disappeared, from several parts of India in which they were, found 50 or 60 years ago. The Cheetah is extinct in India. The Wolf is now highly threatened., Blackbuck and chinkara are poached for meat., Birds such as the beautiful Great Indian Bustards, are vanishing. Unless grassland species are protected they will vanish from their shrinking habitat, as natural and undisturbed grasslands are, left in very few locations. If these animals and, birds are killed or their habitat is reduced further, their extinction will rapidly follow., , What if our grasslands disappear?, If our grasslands are lost we will lose a highly, specialised ecosystem in which plants and animals have been adapted to these habitat conditions over millions of years. Local people will not, be able to support their livestock herds., The extinction of species is a great loss to Mankind. The genes of wild grasses are extremely, useful for developing new crop varieties. New, medicines could well be discovered from wild, grassland plants. It is possible that genes from, wild herbivores such as wild sheep, goats and, antelopes may be used for developing new, strains of domestic animals., , Ecosystems, , Chapter3.p65, , 73, , 73, , 4/9/2004, 5:08 PM
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How can grassland ecosystems be conserved?, Grasslands should not be overgrazed and areas, of the grasslands should be closed for grazing., It is better to collect grass for stall feeding cattle., A part of the grassland in an area must be closed, every year so that a rotational grazing pattern is, established. Fires must be prevented and rapidly controlled. In hilly areas soil and water management in each micro-catchment helps grasslands to return to a natural highly productive, ecosystem., To protect the most natural undisturbed grassland ecosystems, Sanctuaries and National Parks, must be created. Their management should focus on preserving all their unique species of, plants and animals. Thus they should not be, converted into plantations of trees. The open, grassland is the habitat of its specialised fauna., Planting trees in these areas reduces the natural features of this ecosystem resulting in the, destruction of this unique habitat for wildlife., , What should we do?, • There is a need to preserve the few natural, grassland areas that still survive by creating, National Parks and Wildlife Sanctuaries in, all the different types of grasslands., •, , Animals such as the wolf, blackbuck,, chinkara and birds such as bustards and, floricans have now become rare all over the, country. They must be carefully protected, in the few National Parks and Wildlife Sanctuaries that have natural grassland habitats, as well as outside these Protected Areas., , •, , We need to create an awareness among, people that grasslands are of great value. If, we are all concerned about our disappearing grasslands and their wonderful wildlife,, the Government will be motivated to protect them., , •, , Keeping grasslands alive is a National priority., , 3.7.3 Desert ecosystem, Desert and semi arid lands are highly specialised, and sensitive ecosystems that are easily destroyed by human activities. The species of these, dry areas can live only in this specialised habitat., , What is a desert or a semi-arid ecosystem?, Deserts and semi arid areas are located in Western India and the Deccan Plateau. The climate, in these vast tracts is extremely dry. There are, also cold deserts such as in Ladakh, which are, located in the high plateaus of the Himalayas., The most typical desert landscape that is seen, in Rajasthan is in the Thar Desert. This has sand, dunes. There are also areas covered with sparse, grasses and a few shrubs, which grow if it rains., In most areas of the Thar the rainfall is scanty, and sporadic. In an area it may rain only once, every few years. In the adjoining semi arid tract, the vegetation consists of a few shrubs and, thorny trees such as kher and babul., The Great and Little Rann of Kutch are highly, specialised arid ecosystems. In the summers they, are similar to a desert landscape. However as, , Desert and Semi arid eco systems, , Environmental Studies for Undergraduate Courses, , 74, , Chapter3.p65, , 74, , 4/9/2004, 5:08 PM
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these are low-lying areas near the sea, they get, converted to salt marshes during the monsoons., During this period they attract an enormous, number of aquatic birds such as ducks, geese,, cranes, storks, etc. The Great Rann is famous,, as it is the only known breeding colony of the, Greater and Lesser Flamingos in our country., The Little Rann of Kutch is the only home of the, wild ass in India., Desert and semi arid regions have a number of, highly specialized insects and reptiles. The rare, animals include the Indian wolf, desert cat,, desert fox and birds such as the Great Indian, Bustard and the Florican. Some of the commoner birds include partridges, quails and, sandgrouse., , How are desert and semi-arid ecosystems, used?, Areas of scanty vegetation with semi-arid scrubland have been used for camel, cattle and goat, grazing in Rajasthan and Gujarat, and for sheep, grazing in the Deccan Plateau., Areas that have a little moisture, such as along, the watercourses, have been used for growing, crops such as jowar, and bajra. The natural, grasses and local varieties of crops have adapted, to growing at very low moisture levels. These, can be used for genetic engineering and developing arid land crops for the future., , What are the threats to desert ecosystems?, Several types of development strategies as well, as human population growth have begun to, affect the natural ecosystem of the desert and, semi arid land. Conversion of these lands, through extensive irrigation systems has, changed several of the natural characteristics, of this region. The canal water evaporates rapidly bringing the salts to the surface. The region, becomes highly unproductive as it becomes saline. Pulling excessive groudwater from tube, , wells lowers the water table creating an even, drier environment. Thus human activities destroy, the naturalness of this unique ecosystem. The, special species that evolved here over millions, of years may soon become extinct., , How can desert ecosystems be conserved?, Desert ecosystems are extremely sensitive. Their, ecological balance that forms a habitat for their, plants and animals is easily disturbed. Desert, people have traditionally protected their meagre water resources. The Bishnois in Rajasthan, are known to have protected their Khejdi trees, and the blackbuck antelope for several generations. The tradition began when the ruler of their, region ordered his army to cut down trees for, his own use. Several Bishnois were said to have, been killed while trying to protect their trees., There is an urgent need to protect residual, patches of this ecosystem within National Parks, and Wildlife Sanctuaries in desert and semi arid, areas. The Indira Gandhi Canal in Rajasthan is, destroying this important natural arid ecosystem, as it will convert the region into intensive, agriculture. In Kutch, areas of the little Rann,, which is the only home of the Wild Ass, will be, destroyed by the spread of salt works., Development Projects alter the desert and arid, landscape. There is a sharp reduction in the habitat available for its specialised species bringing, them to the verge of extinction. We need a sustainable form of development that takes the, special needs of the desert into account., , 3.7.4 Aquatic ecosystems, The aquatic ecosystems constitute the marine, environments of the seas and the fresh water, systems in lakes, rivers, ponds and wetlands., These ecosystems provide human beings with a, wealth of natural resources. They provide goods, that people collect for food such as fish and, , Ecosystems, , Chapter3.p65, , 75, , 75, , 4/9/2004, 5:08 PM
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Aquatic ecosystems, , crustaceans. Natural aquatic systems such as rivers and seas break down chemical and organic, wastes created by man. However, this function, has limitations, as the aquatic ecosystem cannot handle great quantities of waste. Beyond a, certain limit, pollution destroys this natural function., If aquatic ecosystems are misused or over utilized, their ability to provide resources suffers in, the long term. Over-fishing leads to a fall in the, fish catch. River courses that are changed by, dams to provide electricity affect thousands of, people who do not get a continuous supply of, water downstream for their daily use. When, wetlands are drained, their connected rivers tend, to cause floods. These are all examples of unsustainable changes in the use of natural resources and nature’s ecosystems that are dependent on hydrological regimes., Water is an important factor in all our ecosystems. Several ecosystems exist in freshwater and, , marine salt water. There is very little fresh water on earth, which is a key resource for people, all over the world., , What is an aquatic ecosystem?, In aquatic ecosystems, plants and animals live, in water. These species are adapted to live in, different types of aquatic habitats. The special, abiotic features are its physical aspects such as, the quality of the water, which includes its clarity, salinity, oxygen content and rate of flow., Aquatic ecosystems may be classified as being, stagnant ecosystems, or running water ecosystems. The mud gravel or rocks that form the, bed of the aquatic ecosystem alter its characteristics and influence its plant and animal species composition. The aquatic ecosystems are, classified into freshwater, freshwater, brackish and marine, ecosystems, which are based on the salinity levels., The fresh water ecosystems that have running, water are streams and rivers. Ponds, tanks and, lakes are ecosystems where water does not flow., Wetlands are special ecosystems in which the, water level fluctuates dramatically in different, seasons. They have expanses of shallow water, with aquatic vegetation, which forms an ideal, habitat for fish, crustacea and water birds., Marine ecosystems are highly saline, while brackish areas have less saline water such as in river, deltas. Coral reefs are very rich in species and, , Types of Aquatic ecosystems, Fresh water ecosystems, Flowing water, Streams, , Rivers, , Still water, , Brackish water, , Ponds,, wetlands,, lakes, , Deltas, , Saline water, Coastal, shallows,, Coral reefs, , Deep ocean, , Environmental Studies for Undergraduate Courses, , 76, , Chapter3.p65, , Marine ecosystems, , 76, , 4/9/2004, 5:08 PM
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are found in only a few shallow tropical seas., The richest coral reefs in India are around the, Andaman and Nicobar islands and in the gulf of, Kutch., , water consists of floating weeds and rooted vegetation on the periphery which grow on the, muddy floor under water and emerge out of, the surface of the water., , Brackish water ecosystems in river deltas are, covered by mangrove forests and are among, the world’s most productive ecosystems in terms, of biomass production. The largest mangrove, swamps are in the Sunderbans in the delta of, the Ganges., , As the pond fills in the monsoon a large number of food chains are formed. Algae is eaten, by microscopic animals, which are in turn eaten, by small fish on which larger carnivorous fish, depend. These are in turn eaten by birds such, as kingfishers, herons and birds of prey. Aquatic, insects, worms and snails feed on the waste, material excreted by animals and the dead or, decaying plant and animal matter. They act on, the detritus, which is broken down into nutrients which aquatic plants can absorb, thus completing the nutrient cycle in the pond. The temporary ponds begin to dry after the rains and, the surrounding grasses and terrestrial plants, spread into the moist mud that is exposed. Animals such as frogs, snails and worms remain dormant in the mud, awaiting the next monsoon., , The Pond ecosystem, The pond is the simplest aquatic ecosystem to, observe., There are differences in a pond that is temporary and has water only in the monsoon, and a, larger tank or lake that is an aquatic ecosystem, throughout the year. Most ponds become dry, after the rains are over and are covered by terrestrial plants for the rest of the year., , Lake ecosystem, When a pond begins to fill during the rains, its, life forms such as the algae and microscopic, animals, aquatic insects, snails, and worms come, out of the floor of the pond where they have, remained dormant in the dry phase. Gradually, more complex animals such as crabs frogs and, fish return to the pond. The vegetation in the, , Pond, , A lake ecosystem functions like a giant permanent pond. A large amount of its plant material, is the algae, which derives energy from the sun., This is transferred to the microscopic animals,, which feed on the algae. There are fish that are, herbivorous and are dependent on algae and, aquatic weeds. The small animals such as, snails are used as food by small carnivorous fish, which in turn are eaten by larger, carnivorous fish. Some specialised fish,, such as catfish, feed on the detritus on the, muddy bed of the lake., Energy cycles through the lake ecosystem, from the sunlight that penetrates the water surface to the plants. From plants energy is transferred to herbivorous animals, and carnivores. Animals excrete waste, products, which settle on the bottom of, the lake. This is broken down by small ani-, , Ecosystems, , Chapter3.p65, , 77, , 77, , 4/9/2004, 5:08 PM
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mals that live in the mud in the floor of the lake., This acts as the nutrient material that is used by, aquatic plants for their growth. During this process plants use Carbon from CO2 for their, growth and in the process release Oxygen. This, Oxygen is then used by aquatic animals, which, filter water through their respiratory system., , Stream and River ecosystems, Streams and rivers are flowing water ecosystems, in which all the living forms are specially adapted, to different rates of flow. Some plants and animals such as snails and other burrowing animals can withstand the rapid flow of the hill, streams. Other species of plants and animals, such as water beetles and skaters can live only, in slower moving water. Some species of fish,, such as Mahseer, go upstream from rivers to, hill streams for breeding. They need crystal clear, water to be able to breed. They lay eggs only in, clear water so that their young can grow successfully., As deforestation occurs in the hills the water in, the streams that once flowed throughout the, year become seasonal. This leads to flash floods, in the rains and a shortage of water once the, streams dry up after the monsoon., , in this ecosystem vary from microscopic algae, to large seaweeds. There are millions of zooplankton and a large variety of invertebrates on, which live fish, turtles and marine mammals., The shallow areas near Kutch and around the, Andaman and Nicobar Islands are some of the, most incredible coral reefs in the world. Coral, reefs are only second to tropical evergreen forests in their richness of species. Fish, crustacea,, starfish, jellyfish and the polyps that deposit the, coral are a few of the thousands of species that, form this incredible world under the shallow sea., Deforestation of adjacent mangroves leads to, silt being carried out to sea where it is deposited on the coral which then dies. There are, many different types of coastal ecosystems, which are highly dependent on the tide., The marine ecosystem is used by coastal, fisherfolk for fishing which forms their livelihood., In the past, fishing was done at a sustainable, level. The marine ecosystem continued to maintain its abundant supply of fish over many generations. Now with intensive fishing by using, giant nets and mechanised boats, fish catch in, the Indian Ocean has dropped significantly., , Seashore ecosystems, The community of flora and fauna of streams, and rivers depends on the clarity, flow and oxygen content as well as the nature of their beds., The stream or river can have a sandy, rocky or, muddy bed, each type having its own species of, plants and animals., , Marine ecosystems, , Various shore birds feed on their prey by probing into the sand or mud on the sea shore., , The Indian Ocean, the Arabian Sea and the Bay, of Bengal constitute the marine ecosystems, around peninsular India. In the coastal area the, sea is shallow while further away, it is deep. Both, these are different ecosystems. The producers, , Several different species of fish are caught by, fishermen. In many areas the fish catch has decreased during the last decade or two., Environmental Studies for Undergraduate Courses, , 78, , Chapter3.p65, , Beaches can be sandy, rocky, shell covered or, muddy. On each of these different types, there, are several specific species which have evolved, to occupy a separate niche. There are different, crustacea such as crabs that make holes in the, sand., , 78, , 4/9/2004, 5:08 PM
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How are aquatic ecosystems used?, Man uses aquatic ecosystems for the clean freshwater on which his life is completely dependent., We need clean water to drink and for other, domestic uses. Water is essential for agriculture., Fisherfolk use the aquatic ecosystems to earn a, livelihood. People catch fish and crabs. They also, collect edible plants. This is used locally as food, or for sale in the market. Over fishing leads to a, serious decline in the catch and a long-term loss, of income for fisherfolk., Marshes and wetlands are of great economic, importance for people who live on their fish,, crustacea, reeds, grasses and other produce., Modern man impounds water in dams to be able, to store it throughout the year. Agriculture and, industry are highly dependent on large quantities of water. However this leads to problems, for tribal people who have lived there before, the dams were built as they are displaced to, build large dams. These dams make rich people, richer in the farmland and supports people in, large urban centres that use enormous quantities of water. The poor tribal folk become even, poorer as the natural resources they depend on, are taken away as their lands are submerged, under the water of the dam., Dams are built across rivers to generate electricity. A large proportion of this energy is used, by urban people, by agriculturists in irrigated, farmlands and in enormous quantities for industry. Large dams have serious ill effects on natural river ecosystems. While water from dams, used for irrigation has lead to economic prosperity in some areas, in semiarid areas that are, artificially irrigated the high level of evaporation, leads to severe salinisation as salts are brought, up into the surface layers of the soil. This makes, such lands gradually more and more saline and, unproductive., , What are the threats to aquatic ecosystems?, Water pollution occurs from sewage and poorly, managed solid waste in urban areas when it, enters the aquatic ecosystem of lakes and rivers. Sewage leads to a process called eutrophication, which destroys life in the water as the, oxygen content is severely reduced. Fish and, crustacea cannot breathe and are killed. A foul, odour is produced. Gradually the natural flora, and fauna of the aquatic ecosystem is destroyed., In rural areas the excessive use of fertilisers, causes an increase in nutrients, which leads to, eutrophication. Pesticides used in adjacent fields, pollute water and kills off its aquatic animals., Chemical pollution from industry kills a large, number of life forms in adjacent aquatic ecosystems. Contamination by heavy metals and, other toxic chemicals affects the health of people, who live near these areas as they depend on, this water., , CASE STUDY, Threats to wetlands in Assam, Almost 40% of all wetlands in Assam are, under threat. A survey conducted by the, Assam Remote Sensing Application Center, (ARSAC), Guwahati, and the Space Research, Center, Ahemadabad, has revealed that, 1367 out of 3513 wetlands in Assam are, under severe threat due to invasion of, aquatic weeds and several developmental, activities. The wetlands of Assam form the, greatest potential source of income for the, State in terms of fisheries and tourism., Though the wetlands of Assam have the capacity of producing 5,000 tones of fish per, hectare per year, around 20,000 tones of, fish have to be imported to meet local demands. This is primarily due to poor wetland, management., , Ecosystems, , Chapter3.p65, , 79, , 79, , 4/9/2004, 5:08 PM
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How can aquatic ecosystems be conserved?, For sustainable use of an aquatic ecosystem,, water pollution must be prevented. It does not, make sense to allow water to be polluted and, then try to clean it up., Changing the nature of the aquatic ecosystem, from a flowing water ecosystem to a static ecosystem destroys its natural biological diversity., Thus dams across rivers decrease the population of species that require running water, while, favouring those that need standing water., Aquatic ecosystems, especially wetlands, need, protection by including them in Sanctuaries or, National Parks in the same way in which we, protect natural forests. These sanctuaries in, aquatic ecosystems protect a variety of forms, of life as well as rare fish which are now highly, endangered such as the Mahseer. Wetland, Sanctuaries and National Parks are of greatest, importance as this is one of the most threatened of our ecosystems. As the proportion of, the earth’s surface that is naturally covered by, wetlands is very small compared to forests or, grasslands, the wetland ecosystems are very, highly threatened., , Environmental Studies for Undergraduate Courses, , 80, , Chapter3.p65, , 80, , 4/9/2004, 5:08 PM
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UNIT 4:, , Biodiversity, , 4.1 INTRODUCTION – DEFINITION: GENETIC, SPECIES, ECOSYSTEM DIVERSITY, 4.1.1 Genetic diversity, 4.1.2 Species diversity, 4.1.3 Ecosystem diversity, , 82, 82, 82, 83, , 4.2 BIOGEOGRAPHIC CLASSIFICATION OF INDIA, , 84, , 4.3 VALUE OF BIODIVERSITY: CONSUMPTIVE, PRODUCTIVE USE, SOCIAL, ETHICAL,, AESTHETIC AND OPTION VALUES, 4.3.1Consumptive value, 4.3.2 Productive value, 4.3.3 Social value, 4.3.4 Ethical value, 4.3.5 Aesthetic value, 4.3.6 Option value, , 84, 85, 86, 86, 88, 88, 88, , 4.4 BIODIVERSITY AT GLOBAL, NATIONAL AND LOCAL LEVELS, , 88, , 4.5 INDIA AS A MEGA DIVERSITY NATION, , 89, , 4.6 HOTSPOTS OF BIODIVERSITY, , 90, , 4.7 THREATS TO BIODIVERSITY: HABITAT LOSS, POACHING OF WILDLIFE,, MAN-WILDLIFE CONFLICTS, , 91, , 4.8 ENDANGERED AND ENDEMIC SPECIES OF INDIA, 4.8.1 Common Plant species, 4.8.2 Common Animal species, , 94, 94, 99, , 4.9 CONSERVATION OF BIODIVERSITY: IN-SITU AND EX-SITU, 4.9.1 In-situ conservation, 4.9.2 Ex-situ conservation, Biodiversity, , 104, 104, 108, 81
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4.1 INTRODUCTION, The great variety of life on earth has provided, for man’s needs over thousands of years. This, diversity of living creatures forms a support system which has been used by each civilization, for its growth and development. Those that used, this “bounty of nature” carefully and sustainably, survived. Those that overused or misused it disintegrated., , What is biodiversity?, Biological diversity deals with the degree of, nature’s variety in the biosphere. This variety can, be observed at three levels; the genetic variability within a species, the variety of species within, a community, and the organisation of species, in an area into distinctive plant and animal communities constitutes ecosystem diversity., , 4.1.1 Genetic diversity, Science has attempted to classify and categorize the variability in nature for over a century., This has led to an understanding of its organization into communities of plants and animals., This information has helped in utilizing the, earth’s biological wealth for the benefit of humanity and has been integral to the process of, ‘development’. This includes better health care,, better crops and the use of these life forms as, raw material for industrial growth which has led, to a higher standard of living for the developed, world. However this has also produced the, modern consumerist society, which has had a, negative effect on the diversity of biological resources upon which it is based. The diversity of, life on earth is so great that if we use it, sustainably we can go on developing new products from biodiversity for many generations. This, can only happen if we manage biodiversity as a, precious resource and prevent the extinction of, species., , Definition:, ‘Biological diversity’ or biodiversity is that part, of nature which includes the differences in genes, among the individuals of a species, the variety, and richness of all the plant and animal species, at different scales in space, locally, in a region,, in the country and the world, and various types, of ecosystems, both terrestrial and aquatic,, within a defined area., , 82, , Each member of any animal or plant species differs widely from other individuals in its genetic, makeup because of the large number of combinations possible in the genes that give every, individual specific characteristics. Thus, for example, each human being is very different from, all others. This genetic variability is essential for, a healthy breeding population of a species. If, the number of breeding individuals is reduced,, the dissimilarity of genetic makeup is reduced, and in-breeding occurs. Eventually this can lead, to the extinction of the species. The diversity in, wild species forms the ‘gene pool’ from which, our crops and domestic animals have been developed over thousands of years. Today the variety of nature’s bounty is being further, harnessed by using wild relatives of crop plants, to create new varieties of more productive crops, and to breed better domestic animals. Modern, biotechnology manipulates genes for developing better types of medicines and a variety of, industrial products., , 4.1.2 Species diversity, The number of species of plants and animals, that are present in a region constitutes its species diversity. This diversity is seen both in natural ecosystems and in agricultural ecosystems., Some areas are more rich in species than others. Natural undisturbed tropical forests have a, much greater species richness than plantations, developed by the Forest Department for timber, Environmental Studies for Undergraduate Courses
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production. A natural forest ecosystem provides, a large number of non-wood products that local people depend on such as fruit, fuel wood,, fodder, fiber, gum, resin and medicines. Timber, plantations do not provide the large variety of, goods that are essential for local consumption., In the long-term the economic sustainable returns from non-wood forest products is said to, be greater than the returns from felling a forest, for its timber. Thus the value of a natural forest,, with all its species richness is much greater than, a plantation. Modern intensive agricultural ecosystems have a relatively lower diversity of crops, than traditional agropastoral farming systems, where multiple crops were planted., At present conservation scientists have been able, to identify and categorise about 1.8 million species on earth. However, many new species are, being identified, especially in the flowering, plants and insects. Areas that are rich in species, diversity are called ‘hotspots’ of diversity. India, is among the world’s 15 nations that are exceptionally rich in species diversity., , productivity eventually decreases and they are, then said to be degraded. India is exceptionally, rich in its ecosystem diversity., , 4.1.3 Ecosystem diversity, , Most species appear to have a life span extending over several million years. Their adaptability, to gradual changes in their habitat, and interactions with newly formed species produce, groups of inter linked organisms that continue, to evolve together. Food chains, prey-predator, relationships, parasitism (complete dependence, on another species), commensalism (a partnership beneficial to both species), etc. are important examples. Behavioural patterns of the, different species comprising a community of species links them to each other through their, breeding biology, feeding patterns, migrations,, etc. As ancient species became extinct due to, geological upheavals, they left behind empty, ‘niches’ in the habitat that stimulated existing, species to fill them through the formation of, new species. The Earth’s ancient history has seen, periods of mega extinctions, which have been, followed by periods of formation of new species. Though these repeatedly led to a drastic, , There are a large variety of different ecosystems, on earth, which have their own complement of, distinctive inter linked species based on the differences in the habitat. Ecosystem diversity can, be described for a specific geographical region,, or a political entity such as a country, a State or, a taluka. Distinctive ecosystems include landscapes such as forests, grasslands, deserts,, mountains, etc., as well as aquatic ecosystems, such as rivers, lakes, and the sea. Each region, also has man-modified areas such as farmland, or grazing pastures., An ecosystem is referred to as ‘natural’ when it, is relatively undisturbed by human activities, or, ‘modified’ when it is changed to other types of, uses, such as farmland or urban areas. Ecosystems are most natural in wilderness areas. If, natural ecosystems are overused or misused their, Biodiversity, , Evolution and the Genesis of Biodiversity:, The origins of life on earth some three and a, half billion years ago are obscure. Life was probably initiated as a product of organic reactions, in the Earth’s primordial seas. Alternative possibilities such as life beginning in a muddy ooze,, or of life having been seeded from outer space, have also been suggested. Once life took hold, on the planet, it began gradually to diversify., Unicellular unspecialized forms gradually evolved, into complex multi-cellular plants and animals., Evolution is related to the ability of living organisms to adapt to changes in their environment., Thus the abiotic changes in nature such as climatic and atmospheric upheavals, repeated glaciations, continental drift and the formation of, geographical barriers, segregated different communities of plants and animals and gradually, lead to the formation of new species over millions of years., , 83
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reduction in the number of species, the diversity of life recuperated each time by gradually, increasing the number of species existing on, earth. This however took millions of years, as, evolution is a very slow process. Thus when man, came on the scene some 2 million years ago,, the earth was more rich in species than ever, before. During the recent past however, extinctions due to the activities of modern man have, begun to take place so rapidly that nature has, had no time to evolve new species. The earth is, loosing species more rapidly than ever before., , 4. The Gangetic and Bhramaputra plains., , The diversity of life at all three organisational, levels, genetic, species and ecosystem, is thus, being rapidly modified by modern man. This is, a great loss to future generations who will follow us., , 9. The Andaman and Nicobar Islands., , 5. The Thar Desert of Rajasthan., 6. The semi arid grassland region of the, Deccan plateau Gujarat, Maharashtra,, Andra Pradesh, Karnataka and Tamil Nadu., 7. The Northeast States of India,, 8. The Western Ghats in Maharashtra,, Karnataka and Kerala., , 10. The long western and eastern coastal belt, with sandy beaches, forests and mangroves., , 4.3 VALUE OF BIODIVERSITY, 4.2 BIOGEOGRAPHIC CLASSIFICATION OF, INDIA, Our country can be conveniently divided into, ten major regions, based on the geography, climate and pattern of vegetation seen and the, communities of mammals, birds, reptiles, amphibia, insects and other invertebrates that live, in them. Each of these regions contains a variety of ecosystems such as forests, grasslands,, lakes, rivers, wetlands, mountains and hills,, which have specific plant and animal species., , India’s Biogeographic Zones, 1. The cold mountainous snow covered Trans, Himalayan region of Ladakh., 2. The Himalayan ranges and valleys of Kashmir, Himachal Pradesh, Uttarakhand, Assam, and other North Eastern States., 3. The Terai, the lowland where the Himalayan, rivers flow into the plains., , 84, , Environmental services from species and ecosystems are essential at global, regional and local levels. Production of oxygen, reducing carbon, dioxide, maintaining the water cycle, protecting soil are important services. The world now, acknowledges that the loss of biodiversity contributes to global climatic changes. Forests are, the main mechanism for the conversion of carbon dioxide into carbon and oxygen. The loss, of forest cover, coupled with the increasing release of carbon dioxide and other gases through, industrialization contributes to the ‘greenhouse, effect’. Global warming is melting ice caps, resulting in a rise in the sea level which will submerge the low lying areas in the world. It is, causing major atmospheric changes, leading to, increased temperatures, serious droughts in, some areas and unexpected floods in other areas., Biological diversity is also essential for preserving ecological processes, such as fixing and recycling of nutrients, soil formation, circulation, and cleansing of air and water, global life support (plants absorb CO2, give out O2), maintainEnvironmental Studies for Undergraduate Courses
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ing the water balance within ecosystems, watershed protection, maintaining stream and river, flows throughout the year, erosion control and, local flood reduction., Food, clothing, housing, energy, medicines, are, all resources that are directly or indirectly linked, to the biological variety present in the biosphere., This is most obvious in the tribal communities, who gather resources from the forest, or, fisherfolk who catch fish in marine or freshwater ecosystems. For others, such as agricultural, communities, biodiversity is used to grow their, crops to suit the environment. Urban communities generally use the greatest amount of, goods and services, which are all indirectly drawn, from natural ecosystems., It has become obvious that the preservation of, biological resources is essential for the well-being and the long-term survival of mankind. This, diversity of living organisms which is present in, the wilderness, as well as in our crops and livestock, plays a major role in human ‘development’. The preservation of ‘biodiversity’ is, therefore integral to any strategy that aims at, improving the quality of human life., , 4.3.1 Consumptive use value, The direct utilisation of timber, food, fuelwood,, fodder by local communities., The biodiversity held in the ecosystem provides, forest dwellers with all their daily needs, food,, building material, fodder, medicines and a variety of other products. They know the qualities, and different uses of wood from different species of trees, and collect a large number of local, fruits, roots and plant material that they use as, food, construction material or medicines., Fisherfolk are highly dependent on fish and, know where and how to catch fish and other, edible aquatic animals and plants., Biodiversity, , Man and the Web of Life, The Biodiversity of an area influences every, aspect of the lives of people who inhabit it., Their living space and their livelihoods depend on the type of ecosystem. Even people, living in urban areas are dependent on the, ecological services provided by the wilderness in the PAs. We frequently don’t see this, in everyday life as it is not necessarily overt., It is linked with every service that nature provides us. The quality of water we drink and, use, the air we breathe, the soil on which, our food grows are all influenced by a wide, variety of living organisms both plants and, animals and the ecosystem of which each, species is linked with in nature., While it is well known that plant life removes, carbon dioxide and releases the oxygen we, breathe, it is less obvious that fungi, small, soil invertebrates and even microbes are essential for plants to grow., That a natural forest maintains the water in, the river after the monsoon, or that the absence of ants could destroy life on earth, are, to be appreciated to understand how we are, completely dependent on the living ‘web of, life’ on earth., The wilderness is an outcome of a long evolutionary process that has created an, unimaginably large diversity of living species,, their genetic differences and the various ecosystems on earth in which all living creatures, live. This includes mankind as well. Think, about this and we cannot but want to protect out earth’s unique biodiversity. We are, highly dependent on these living resources., , 85
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4.3.2 Productive use value, Marketable goods., , Value of MFP>Timber (which is part of sustainable use)., , development. A variety of industries such as, pharmaceuticals are highly dependent on identifying compounds of great economic value from, the wide variety of wild species of plants located, in undisturbed natural forests. This is called biological prospecting., , 4.3.3 Social values, The biotechnologist uses biorich areas to ‘prospect’ and search for potential genetic properties in plants or animals that can be used to, develop better varieties of crops that are used, in farming and plantation programs or to develop better livestock. To the pharmacist, biological diversity is the raw material from which, new drugs can be identified from plant or animal products. To industrialists, biodiversity is a, rich store-house from which to develop new, products. For the agricultural scientist the, biodiversity in the wild relatives of crop plants is, the basis for developing better crops., Genetic diversity enables scientists and farmers, to develop better crops and domestic animals, through careful breeding. Originally this was, done by selecting or pollinating crops artificially, to get a more productive or disease resistant, strain. Today this is increasingly being done by, genetic engineering, selecting genes from one, plant and introducing them into another. New, crop varieties (cultivars) are being developed, using the genetic material found in wild relatives of crop plants through biotechnology., Even today, species of plants and animals are, being constantly discovered in the wild. Thus, these wild species are the building blocks for, the betterment of human life and their loss is a, great economic loss to mankind. Among the, known species, only a tiny fraction have been, investigated for their value in terms of food, or, their medicinal or industrial potential., , While traditional societies which had a small, population and required less resources had preserved their biodiversity as a life supporting resource, modern man has rapidly depleted it even, to the extent of leading to the irrecoverable loss, due to extinction of several species. Thus apart, from the local use or sale of products of, biodiversity there is the social aspect in which, more and more resources are used by affluent, societies. The biodiversity has to a great extent, been preserved by traditional societies that valued it as a resource and appreciated that its, depletion would be a great loss to their society., The consumptive and productive value of, biodiversity is closely linked to social concerns, in traditional communities. ‘Ecosystem people’, value biodiversity as a part of their livelihood as, well as through cultural and religious sentiments., A great variety of crops have been cultivated in, traditional agricultural systems and this permitted a wide range of produce to be grown and, marketed throughout the year and acted as an, insurance against the failure of one crop. In recent years farmers have begun to receive economic incentives to grow cash crops for national, or international markets, rather than to supply, local needs. This has resulted in local food shortages, unemployment (cash crops are usually, mechanised), landlessness and increased vulnerability to drought and floods., , Preservation of biodiversity has now become, essential for industrial growth and economic, 86, , Environmental Studies for Undergraduate Courses
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Commonly used modern drugs derived from plant sources:, DRUG, , PLANT SOURCE, , USE, , Atropine, , Belladonna, , Anticholinergic: reduces intestinal pain in diarrhoea., , Bromelain, , Pineapple, , Controls tissue inflammation due to infection., , Caffeine, , Tea, Coffee, , Stimulant of the central nervous system., , Camphor, , Camphor tree, , Rebefacient: increases local blood supply., , Cocaine, , Cocoa, , Analgesic and local anesthetic: reduces pain and, prevents pain during surgery., , Codeine, , Opium poppy, , Analgesic: reduces pain., , Morphine, , Opium poppy, , Analgesic: controls pain., , Colchicine, , Autumn crocus, , Anticancer agent., , Digitoxin, , Common foxglove, , Cardiac stimulant used in heart diseases., , Diosgenin, , Wild yams, , Source of female contraceptive: prevents pregnancy., , L-Dopa, , Velvet bean, , Controls Parkinson’s Disease which leads to jerky, movements of the hands, , Ergotamine, , Smut-of-rye or ergot, , Control of haemorrhage and migraine headaches., , Glaziovine, , ocotea glaziovii, , Antidepressant: Elevates mood of depressed patients., , Gossypol, , Cotton, , Male contraceptive., , Indicine N-oxide, , heliotropium indicum, , Anticancer agent., , Menthol, , Mint, , Rubefacient: increases local blood supply and reduces, pain on local application., , Monocrotaline, , Cotolaria sessiliflora, , Anticancer agent., , Papain, , Papaya, , Dissolves excess protein and mucus, during digestion., , Penicillin, , Penicillium fungi, , General antibiotic, skills bacteria and controls infection, by various micro-organisms., , Quinine, , Yellow cinochona, , Antimalarial., , Reserpine, , Indian snakeroot, , Reduces high blood pressure., , Scopolamine, , Thorn apple, , Sedative., , Taxol, , Pacific yew, , Anticancer (ovarian)., , Vinblastine,, vincristine, , Rosy periwinkle, (Vinca rosea) (Sadaphali), , Anticancer agent: Controls cancer in children., , From: ‘The Diversity of Life’; Edward O. Wilson, (Norton Paperback. In association with Havard University Press – 1993), , Biodiversity, , 87
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4.3.4 Ethical and moral values, Ethical values related to biodiversity conservation are based on the importance of protecting, all forms of life. All forms of life have the right, to exist on earth. Man is only a small part of the, Earth’s great family of species. Don’t plants and, animals have an equal right to live and exist on, our planet which is like an inhabited spaceship?, We do not know if life as we know it exists elsewhere in the universe. Do we have the right to, destroy life forms or do we have a duty to protect them?, Apart from the economic importance of conserving biodiversity, there are several cultural,, moral and ethical values which are associated, with the sanctity of all forms of life. Indian civilization has over several generations preserved, nature through local traditions. This has been, an important part of the ancient philosophy of, many of our cultures. We have in our country a, large number of sacred groves or ‘deorais’ preserved by tribal people in several States. These, sacred groves around ancient sacred sites and, temples act as gene banks of wild plants., , 4.3.5 Aesthetic value, Knowledge and an appreciation of the presence, of biodiversity for its own sake is another reason to preserve it. Quite apart from killing, wildlife for food, it is important as a tourist attraction. Biodiversity is a beautiful and wonderful aspect of nature. Sit in a forest and listen to, the birds. Watch a spider weave its complex, web. Observe a fish feeding. It is magnificent, and fascinating., Symbols from wild species such as the lion of, Hinduism, the elephant of Buddhism and deities such as Lord Ganesh, and the vehicles of, several deities that are animals, have been venerated for thousands of years. Valmiki begins, his epic story with a couplet on the unfortunate, 88, , killing of a crane by a hunter. The ‘Tulsi’ has, been placed at our doorsteps for centuries., , 4.3.6 Option value, Keeping future possibilities open for their use is, called option value. It is impossible to predict, which of our species or traditional varieties of, crops and domestic animals will be of great use, in the future. To continue to improve cultivars, and domestic livestock, we need to return to, wild relatives of crop plants and animals. Thus, the preservation of biodiversity must also include, traditionally used strains already in existence in, crops and domestic animals., , 4.4 BIODIVERSITY AT GLOBAL, NATIONAL, AND LOCAL LEVELS, There are at present 1.8 million species known, and documented by scientists in the world. However, scientists have estimated that the number, of species of plants and animals on earth could, vary from 1.5 to 20 billion! Thus the majority of, species are yet to be discovered., Most of the world’s bio-rich nations are in the, South, which are the developing nations. In contrast, the majority of the countries capable of, exploiting biodiversity are Northern nations, in, the economically developed world. These nations however have low levels of biodiversity., Thus the developed world has come to support, the concept that biodiversity must be considered to be a ‘global resource’. However, if, biodiversity should form a ‘common property, resource’ to be shared by all nations, there is no, reason to exclude oil, or uranium, or even intellectual and technological expertise as global assets. India’s sovereignty over its biological, diversity cannot be compromised without a revolutionary change in world thinking about sharing of all types of natural resources., Environmental Studies for Undergraduate Courses
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Countries with diversities higher than India are, located in South America such as Brazil, and, South East Asian countries such as Malaysia and, Indonesia. The species found in these countries,, however, are different from our own. This makes, it imperative to preserve our own biodiversity, as a major economic resource. While few of the, other ‘megadiversity nations’ have developed, the technology to exploit their species for biotechnology and genetic engineering, India is capable of doing so., Throughout the world, the value of biologically, rich natural areas is now being increasingly appreciated as being of unimaginable value. International agreements such as the World, Heritage Convention attempt to protect and, support such areas. India is a signatory to the, convention and has included several protected, Areas as World Heritage sites. These include, Manas on the border between Bhutan and India, Kaziranga in Assam, Bharatpur in U.P.,, Nandadevi in the Himalayas, and the Sunderbans, in the Ganges delta in West Bengal., India has also signed the Convention in the, Trade of Endangered Species (CITES) which, is intended to reduce the utilization of endangered plants and animals by controlling trade in, their products and in the pet trade., , 4.5 INDIA AS A MEGA DIVERSITY NATION, Geological events in the landmass of India have, provided conditions for high levels of biological, diversity. A split in the single giant continent, around 70 million years ago, led to the formation of northern and southern continents, with, India a part of Gondwanaland - the southern, landmass, together with Africa, Australia and, the Antarctic. Later tectonic movements shifted, India northward across the equator to join the, Northern Eurasian continent. As the intervening shallow Tethis Sea closed down, plants and, animals that had evolved both in Europe and in, Biodiversity, , the Far East migrated into India before the, Himalayas had formed. A final influx came from, Africa with Ethiopian species, which, were, adapted to the Savannas and semi-arid regions., Thus India’s special geographical position between three distinctive centres of biological evolution and radiation of species is responsible for, our rich and varied biodiversity., Among the biologically rich nations, India stands, among the top 10 or 15 countries for its great, variety of plants and animals, many of which, are not found elsewhere. India has 350 different mammals (rated eight highest in the world),, 1,200 species of birds (eighth in the world), 453, species of reptiles (fifth in the world) and 45,000, plant species, of which most are angiosperms,, (fifteenth in the world). These include especially, high species diversity of ferns (1022 species) and, orchids (1082 species). India has 50,000 known, species of insects, including 13,000 butterflies, and moths. It is estimated that the number of, unknown species could be several times higher., It is estimated that 18% of Indian plants are, endemic to the country and found nowhere, else in the world. Among the plant species the, flowering plants have a much higher degree of, endemism, a third of these are not found elsewhere in the world. Among amphibians found, in India, 62% are unique to this country. Among, lizards, of the 153 species recorded, 50% are, endemic. High endemism has also been recorded for various groups of insects, marine, worms, centipedes, mayflies and fresh water, sponges., India’s World, Ranking, , Number of, species in India, , Mammals, , 8th, , 350, , Birds, , 8th, , 1200, , Reptiles, , 5th, , 453, , Amphibia, , 15th, , 182, , 15th-20th, , 14,500, , Angiosperms, , 89
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Apart from the high biodiversity of Indian wild, plants and animals there is also a great diversity, of cultivated crops and breeds of domestic livestock. This is a result of several thousand years, during which civilizations have grown and flourished in the Indian subcontinent. The traditional, cultivars included 30,000 to 50,000 varieties of, rice and a number of cereals, vegetables and, fruit. The highest diversity of cultivars is concentrated in the high rainfall areas of the Western Ghats, Eastern Ghats, Northern Himalayas, and the North-Eastern hills., Gene-banks have collected over 34,000 cereals, and 22,000 pulses grown in India. India has 27, indigenous breeds of cattle, 40 breeds of sheep,, 22 breeds of goats and 8 breeds of buffaloes., , 4.6 HOTSPOTS OF BIODIVERSITY, The earth’s biodiversity is distributed in specific, ecological regions. There are over a thousand, major ecoregions in the world. Of these, 200, are said to be the richest, rarest and most distinctive natural areas. These areas are referred, to as the Global 200., It has been estimated that 50,000 endemic, plants which comprise 20% of global plant life,, probably occur in only 18 ‘hot spots’ in the, world. Countries which have a relatively large, proportion of these hot spots of diversity are, referred to as ‘megadiversity nations’., The rate at which the extinction of species is, occurring throughout our country remains ob-, , Global species diversity, Group, , No. of Described Species, , Bacteria and blue-green algae, Fungi, Algae, Bryophytes (Mosses and Liverworts), Gymnosperms (Conifers), Angiosperms (Flowering plants), Protozoans, Sponges, Corals and Jellyfish, Roundworms and earthworms, Crustaceans, Insects, other arthropods and minor Invertebrates, Molluscs, Starfish, Fishes (Teleosts), Amphibians, Reptiles, Birds, Mammals, , 4,760, 46,983, 26,900, 17,000, 750, 250,000, 30,800, 5,000, 9,000, 24,000, 38,000, 751,000, 132,461, 50,000, 6,100, 19,056, 4,184, 6,300, 9,198, 4,170, , (WCMC, 1988), (Reven et al., 1986), (Reven et al., 1986), , (Clements, 1981), (Honacki et al., 1982), , Total: 1,435,662 SPECIES, From ‘Conserving the World’s Biological Diversity WRI, IUCN, CI, WWF-US, The World Bank.’, , 90, , Environmental Studies for Undergraduate Courses
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scure. It is likely to be extremely high as our wilderness areas are shrinking rapidly. Our globally, accepted national ‘hot spots’ are in the forests, of the North-East and the Western Ghats,, which are included in the world’s most biorich, areas. The Andaman and Nicobar Islands are, extremely rich in species and many subspecies, of different animals and birds have evolved., Among the endemic species i.e. those species, found only in India, a large proportion are concentrated in these three areas. The Andaman, and Nicobar Islands alone have as many as 2200, species of flowering plants and 120 species of, ferns. Out of 135 genera of land mammals in, India, 85 (63%) are found in the Northeast. The, Northeast States have 1,500 endemic plant species. A major proportion of amphibian and reptile species, especially snakes, are concentrated, in the Western Ghats, which is also a habitat, for 1,500 endemic plant species., Coral reefs in Indian waters surround the, Andaman and Nicobar Islands, Lakshadweep, Islands, the Gulf areas of Gujarat and Tamil, Nadu. They are nearly as rich in species as tropical evergreen forests!, , 4.7 THREATS TO BIODIVERSITY: HABITAT, LOSS, POACHING OF WILDLIFE, MAN-WILDLIFE CONFLICTS, Man has begun to overuse or misuse most of, these natural ecosystems. Due to this ‘unsustainable’ resource-use, once productive forests, and grasslands have been turned into deserts, and wasteland have increased all over the world., Mangroves have been cleared for fuelwood and, prawn farming, which has led to a decrease in, the habitat essential for breeding of marine fish., Wetlands have been drained to increase agricultural land. These changes have grave economic implications in the longer term., The current destruction of the remaining large, areas of wilderness habitats, especially in the, Biodiversity, , CASE STUDY, Kailadevi Wildlife Sanctuary – Sawai, Madhopur, Rajashtan, While conservation efforts are associated, with conflicts between villagers and Forest, Officials in most Protected Areas across the, country, the Kailadevi Wildlife Sanctuary in, Rajasthan has involved local community initiatives for conservation and regeneration., The Sanctuary was initiated in 1983, over, 674 sq km forming a part of the 1334 sq km, Ranthambore Tiger Reserve. It is located, within the Karauli and Sapotra blocks of, Sawai Madhopur district., The primary occupation of the predominant, Meena and Gujjar communities is pastoralism and subsistence agriculture., Pressures on the sanctuary included migrant, grazers known as the Rabaris, who came, from the Mewar region of Rajasthan with, herds of over 150,000 sheep. Other pressures were from exploitation of timber and, fuelwood and mining. The threat poised by, the migrant grazers spurred the formation, of the “Baragaon ki Panchayat” in 1990,, which in turn initiated a ‘Bhed Bhagao, Andolan’., The Forest Department supported the villagers in the formation of Forest Protection, Committees and Van Suraksha Samitis. The, benefits of involving local people in protection of their resources were obvious. Illegal, felling was checked. The use of forest resources for local use was monitored. The, Forest Protection Committees (FPCs) were, also successful in stopping the mining in the, Sanctuary. Mining is now banned in the, Sanctuary. The people not only protect their, forests but also use their resources judiciously., 91
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super diverse tropical forests and coral reefs, is, the most important threat worldwide to, biodiversity. Scientists have estimated that human activities are likely to eliminate approximately 10 million species by the year 2050., , Loss of species occurs due to the destruction of, natural ecosystems, either for conversion to, agriculture or industry, or by over-extraction of, their resources, or through pollution of air, water and soil., , There are about 1.8 million species of plants and, animals, both large and microscopic, known to, science in the world at present. The number of, species however is likely to be greater by a factor of at least 10. Plants and insects as well as, other forms of life not known to science are, continually being identified in the worlds’ ‘hotspots’ of diversity. Unfortunately at the present, rate of extinction about 25% of the worlds’ species will undergo extinction fairly rapidly. This, may occur at the rate of 10 to 20 thousand species per year, a thousand to ten thousand times, faster than the expected natural rate! Human, actions could well exterminate 25% of the, world’s species within the next twenty or thirty, years. Much of this mega extinction spasm is, related to human population growth, industrialization and changes in land-use patterns. A, major part of these extinctions will occur in ‘biorich’ areas such as tropical forests, wetlands, and, coral reefs. The loss of wild habitats due to rapid, human population growth and short term economic development are major contributors to, the rapid global destruction of biodiversity., , In India, forests and grasslands are continuously, being changed to agricultural land. Encroachments have been legalized repeatedly. Similarly, natural wetland systems have been drained to, establish croplands resulting in loss of aquatic, species. Grasslands that were once sustainably, used by a relatively smaller number of human, beings and their cattle are either changed to, other forms of use or degraded by overgrazing., , Island flora and fauna having high endemism in, small isolated areas surrounded by sea have so, far been most seriously affected by human activity, which has already led to extinction of many, island plants and animals (the dodo is a famous, example). Habitat loss also results from man’s, introduction of species from one area into another, disturbing the balance in existing communities. In the process, the purposely or, accidentally introduced organisms (Eupatorium,, Lantana , Hyacinth, Congress grass or, Parthenium) have led to the extinction of many, local species., , 92, , CASE STUDY:, Kokkare Bellure – Karnataka: Co-existence (Man and Wildlife), The pelican, which is an endangered species, breeds in large numbers at Kokkare Bellur, which is one of the ten known breeding sites, in India. Kokkare Bellure is a village in, Karnataka in Southern India. In December, every year, hundreds of spot billed pelicans,, painted storks, ibis and other birds migrate, to this area to establish breeding colonies, on the tall tamarind trees in the center of, the village. The local people have protected, the birds, believing that they bring good luck, with regard to rain and crops. The villagers, collect a rich supply of the natural fertilizer, that collects below the nests – the guano., The droppings of fish-eating birds are rich in, nitrates., The owners of the trees inhabited by the, birds dig deep pits under the trees, into which, the guano falls. Silt from nearby lakes and, ponds is mixed with the guano which is used, in their fields and sold as fertilizer. They have, now planted trees around their homes to, encourage nesting., Environmental Studies for Undergraduate Courses
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Our natural forests are being deforested for timber and replanted using teak, sal or other single, species for their timber value. Such plantations, do not support the same biological diversity as, a multi-storied natural forest, which has a closed, canopy and a rich understorey of vegetation., When excessive firewood is collected from the, forest by lopping the branches of trees, the forest canopy is opened up and this alters local, biodiversity. Foraging cattle retard the regeneration of the forest as seedlings are constantly, trampled., Increasing human population on the fringes of, our Protected Areas degrade forest ecosystems., This is a major factor to consider in evaluating, the quality of the ecosystem. Repeated fires, started by local grazers to increase grass growth, ultimately reduces regeneration and lowers the, diversity of plant species. Without alternate, sources of fodder this pressure cannot be decreased., Another factor that disrupts forest biodiversity, is the introduction of exotic weeds which are, not a part of the natural vegetation. Common, examples in India are lantana bushes, Eupatorium shrubs and ‘congress’ grass. These have, been imported into the country from abroad and, have invaded several large tracts of our natural, forests. These weeds spread at the expense of, the diverse range of indigenous undergrowth, species. The impact on the diversity of insect,, bird and other wildlife species, though not adequately studied, is quite obvious., In our country a variety of traditional farming, techniques have evolved over several centuries., Cultivation by slash and burn in the Himalayas,, and ‘rab’ by lopping of tree branches to act as a, wood-ash fertilizer in the Western Ghats, are, two such systems. When human population in, these areas was low, these were sustainable, Biodiversity, , methods of agriculture. Unfortunately these areas now have a large number of people who, subsist largely on forest agriculture. These methods are now unsustainable and are leading to a, loss of forest biodiversity., Overharvesting of fish, especially by trawling is, leading to serious depletion of fish stocks. Turtles, are being massacred off the coast of Orissa. The, rare whale shark, a highly endangered species,, is being killed off the coast of Gujarat., Poaching: Specific threats to certain animals are, related to large economic benefits. Skin and, bones from tigers, ivory from elephants, horns, from rhinos and the perfume from the must deer, are extensively used abroad. Bears are killed for, their gall bladders. Corals and shells are also collected for export or sold on the beaches of, Chennai and Kanyakumari. A variety of wild, plants with real or at times dubious medicinal, value are being over harvested. The commonly, collected plants include Rauvolfia, Nuxvomica,, Datura, etc. Collection of garden plants includes, orchids, ferns and moss., , The Rights of Species, We do not see all the varied functions that, biodiversity plays in our lives because they, are not obvious. We rarely see how they are, controlling our environment unless we study, nature. Thus we tend to take short-term actions that can have serious impacts on, biodiversity leading to even extinction of species by disturbing their habitats. Man has no, right to do so. We only share this planet with, millions of other species that also have a right, to survive on earth. It is morally wrong to, allow man’s actions to lead to the extinction, of species., , 93
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4.8 ENDANGERED AND ENDEMIC SPECIES, OF INDIA, , Many plants are threatened due to overharvesting as ingredients in medicinal products., , To appreciate the endemic and endangered species of India it is important to understand the, wide variety of plant and animal species that, are found in the country., , To protect endangered species India has created, the Wildlife Protection Act. This includes lists of, plants and animals categorised according to the, threat on their survival., , Of the well-known species, there are several, which are endangered by human activity. The, endangered species in the country are, categorised as Vulnerable, Rare, Indeterminate, and Threatened. Other species are found only, in India and are thus endemic or restricted to, our country. Some of these may have very localized distribution and are considered highly, endemic., , We know so little about the species diversity of, our country. There are several groups of which, we know very little. Most of us are only aware, of the plight of a few glamorous large mammals, but we need to appreciate the threat to, the less known species of plants and animals., We need to find ways to support the conservation of our incredible wildlife for future generations., , Several plant and animal species in the country, are now found in only one or a few Protected, Areas. Among the important endangered animals are charismatic species such as the tiger,, the elephant, the rhino, etc. The less well-known, major mammals restricted to a single area include the Indian wild ass, the Hangul or, Kashmir stag, the Golden langur, the pygmy, hog and a host of others. There are also endangered bird species such as the Siberian crane,, the Great Indian Bustard, the Florican and, several birds of prey. During the recent past,, vultures which were common a decade ago,, have suddenly disappeared and are now, highly threatened. Equally threatened are several species of reptiles and amphibia. Many, invertebrates are also threatened, including a, large number of species that inhabit our coral, reefs., Many plant species are now increasingly threatened due to changes in their habitats induced, by human activity. Apart from major trees,, shrubs and climbers that are extremely habitat, specific and thus endangered, there are thousands of small herbs which are greatly threatened by habitat loss. Several orchids are yet, another group of plants that are under threat., 94, , 4.8.1 Common Plant species, Teak: This tree is from the Southwest parts of, peninsular India. It is a common tree in deciduous forests. It yields a much sought after timber, used for making excellent furniture. During the, early British period it was cut down from many, forest tracts to build ships. As the stocks were, diminishing, the British selected areas which they, called Reserved Forests where teak was planted, for the Government’s use. Teak is grown extensively by the Forest Department and is a, highly priced wood., The teak tree is identified by its large leaves,, which grow to more than 40 or 50cms long and, 20cms wide. It has tiny flowers and fruit. In the, winter, the trees shed all their leaves. In the, growing season, which begins in April and extends through the monsoon, teak forests are, bright green and shady. Most natural teak forests have various other species of plants and, have a large number of wild animals. Some areas of teak forests that have exceptional populations of wildlife have been included in our, National Parks and Wildlife Sanctuaries., Environmental Studies for Undergraduate Courses
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Sal: This is a common species of several types, of forests of the Northeastern region of India,, extending into Madhya Pradesh and Orissa. It, has bright green foliage and its canopy remains, green nearly throughout the year. Sal wood is, hard and durable. Sal gets a large number of, seeds which are used in making cosmetics. The, sal forests are rich in wild mammals, birds, reptiles and insect life. Several areas are included, in our network of National Parks and Sanctuaries., Mango: This has become one of our most popular horticultural species with different varieties, grown all over the country. The wild mango tree, has small tangy fruit and a big seed in comparison to the large pulpy fruit used in horticulture., The mango tree is an evergreen species and gets, small flowers that are pollinated by insects. In, the forest, fruit dependent animals such as, monkeys, squirrels and fruit eating birds relish, its ripe fruit., , berries on which the larvae feed and grow. The, ficus trees bear berries throughout the year, thus, supplying nutritious food to several animal species when other trees have no fruit. Ficus species are thus known as ‘keystone’ species in the, ecosystem and support a major part of the food, web in several ecosystems. Ficus trees such as, Peepal and Banyan are considered sacred and, are protected in India., Neem: This species is known as Azadirachta Indica. It has been traditionally used in indigenous, medicine. It has small yellow fruit. The leaves, and fruit are bitter to taste. It is used extensively, as an environmentally friendly insecticide. It, grows extremely well in semi-arid regions and, can be planted in afforestation programs where, soil is poor and rainfall is low., , Neem, , Mango, , Ficus sp.: Peepal, Banyan and many other ficus, species form a part of this group of important, trees. They are all ecologically of great importance as many different species of insects, birds, and mammals live on ficus berries. The flowers, are inside the berries. They are pollinated by a, specific wasp which lays its eggs inside the, Ficus, , Biodiversity, , Tamarind: One of the best known Indian trees,, it grows to a large size and is known to live for, over 200 years. Its familiar fruit is a curved pod, with sour pulp and contains a number of squarish seeds. The pulp in the fresh fruit is either, green or red. As it ripens, it turns sticky and, brown and separates from the skin. The tree is, commonly cultivated as a shade tree and for its, edible sour fruit which contains high concentrations of vitamin C. It is used as an additive in, food to give a tangy flavour. It is valued for its, timber as well as for fuelwood., 95
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Babul: This is a thorny species that is characteristic of semi arid areas of Western India and the, Deccan plateau. It grows sparsely in tracts of, grassland and around farms. It is used for fodder and fuelwood. It remains green throughout, the year even under the driest conditions and is, browsed by wild animals and cattle. It has small, leaves and bright yellow flowers and small seedpods with multiple seeds. Its main characteristic, is its long sharp, straight thorns which prevent, excessive browsing of its older branches., Zizyphus: These are the typical small trees and, shrubs that are found in the arid and semi arid, areas of India. Z. mauritiana and Z. jujuba are, the most frequent species. It is a favourite of, frugivorous birds. The tree fruits extensively and, is eaten by a variety of birds and mammals. The, popular fruit is commonly collected and sold in, local markets., Jamun: This tree is an evergreen species which, has a tasty purple fruit. It is a favourite with not, only people but also with many wild birds and, mammals. It grows in many parts of India and, has several varieties with fruit of different sizes., , branches profusely forming a dense crown. The, leaves are elliptical and leathery and its young, leaves are extensively used for making ‘bidis’., The fruit is brownish yellow and astringent., Tendu leaf collection necessitates burning undergrowth and slashing the branches of the trees, to get at the leaves. The resulting disturbance, to wildlife is a serious issue in Protected Areas., Jackfruit: A tree that is planted around many, villages and has huge fruit growing from its, branches. The fruit has a prickly skin. The fruit, when unripe is cooked. Once ripe it is eaten raw, after it turns into a sweet, sticky, golden-yellow, fruit which has a strong smell., Flame of the Forest (Butea monosperma):, This tree grows in many parts of India. It has, bright orange flowers when it is leafless, thus it, is called ‘flame of the forest’. The flowers are, full of nectar which attracts monkeys and many, nectar dependent birds., , Flame of, the forest, Jamun, , Tendu is a mid-sized, deciduous tree, common, in dry deciduous forests throughout the Subcontinent. There are around 50 Indian species., Its bark exfoliates in large rectangular scales. It, 96, , Coral Tree (Erythrina): A common deciduous, tree that is leafless in February when it gets, bright scarlet flowers that are used for their, nectar by many birds such as mynas, crows and, sunbirds, that act as its major pollinators. Its long, black seed pods contain several shiny brown, seeds which germinate well. This tree can also, be propagated by cutting and planting its young, Environmental Studies for Undergraduate Courses
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Erythrina, , Pine, , branches. It is a rapid grower and usually begins to flower in four or five years time., Amla: This deciduous medium sized tree is, known for its sour, green-yellow fruit which is, rich in vitamin C. It is used as a medicine, in, pickles and for dying and tanning. It is frequently, referred to as the Indian ‘olive’, to which it has, no similarity either in appearance or taste., Dipterocarps: This group of trees grows in evergreen forests of the southern part of the, Western Ghats and in the Northeast of India, in, high rainfall areas. It grows to an enormous, height with a wide girth. The seed has a pair of, wing like structures which aid in wind dispersal., Quercus (Oak) is a large tree and is economically an important genus which includes many, trees known for their beautiful shape and their, changing seasonal colours. There are 30 to 40, Indian species of this genus found in the temperate areas throughout the Himalayas. The fruit, is a large, hard, solitary characteristic nut (acorn)., Oaks provide the finest hardwoods of great, strength and durability and were once used for, building ships and bridges. It is a famous wood, for high quality furniture. Some of its species, are excellent fodder plants., Pine: There are 5 species of true pines that are, found in India in the Himalayan region. The timber of these trees is frequently used in construction, carpentry and the paper industry. Pine resin, is used to make turpentine, rosin, tar and pitch., Pine oils are obtained by distillation of leaves, and shoots. Pine leaves are thin and needle-like., Biodiversity, , The male and female spores are produced in, woody cones. Dispersal of pollen is aided by each, grain having two wings., Cycas: These plants are uncommon in India and, have a palm-like appearance. Cycads along with, conifers make up the gymnosperms. They are, among the most primitive seed plants, and have, remained virtually unchanged through the past, 200 million years. There are five species found, in India, mostly in high rainfall areas., Coconut: This tall stately palm has a more or, less straight trunk with circular markings. It, mostly grows in coastal plains. The base is surrounded by a mass of fine roots. It produces the, familiar coconut, filled with liquid and a soft, white edible, initially jelly like material that hardens when the fruit ripens. It is a common ingredient of food in India, especially in the Southern, States. It is extensively cultivated along the, coastal regions and islands of India. Most parts, of the tree yield several useful products such as, broomsticks from its leaves and fiber from the, husk of dried coconuts., Orchids: This is the largest group of flowering, plants in the world with over 18,000 known, species. Of these, 1500 species are found in India, making it one of the largest plant families, in the country with a high concentration of a, staggering 700 species in the Northeastern, States. These plants are terrestrial or epiphytic, herbs. Flowers show a range of bright colours, 97
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has pretty flowers. It grows in shallow poor quality soil. It is a rare, plant and is found in small patches., , Orchid, , and great variations in structure. In some species, one of the petals is distinct from the others, and is called a lip or labellum. This colourful petal, attracts pollinators. In India a large number of, orchid species are found in the Western Ghats,, the Northeast, and the Andaman and Nicobar, Islands. Orchids are however seen in several ecological conditions except extremes such as very, cold or very hot and dry ecosystems., Drosera: This is a small insectivorous plant, usually 5 or 6cms in height, which has tiny hair which, secrete a sticky droplet of fluid on which insects, get stuck. The leaf winds around the struggling, insect which is then slowly digested. The plant, , Drosera, , Lotus: An aquatic floating plant, with a large rhizome, which is, rooted in mud. Its leaves are circular flat and covered with a waxy, coating which protects it from, water. The flower grows on an, erect stalk with several petals ranging from pink violet to white. The, fruit is a spongy cone with multiple round seeds. It is widely distributed in wetland habitats and, shallow parts of lakes and marshy, areas. The rhizome, stalks of the leaves and, seeds are considered delicacies. The fruit is used, for dry decorations. The flower has been a traditional motif in Indian art. The lotus is the National flower of India., Grasses: Grasses form the second largest group, of flowering plants in the world. They are a very, important group of plants as they are used for, various purposes such as making fiber, paper,, thatching material for roofs, oil, gum, medicines, and many other useful products. The economically important grasses include sugarcane, bamboo and cereals like rice, wheat, millets, maize,, etc. Grasses are important as they provide fodder for domestic animals., Bamboo: This is a group of large grasslike species that grow as a clump to great heights in, many forests of India. It is extremely useful and, is used for constructing huts and making several useful household articles in rural areas such, as baskets, farm implements, fences, household, implements, matting, etc. The young shoots are, used as food. It is extensively used in the pulp, and paper industry as a raw material., Bamboos flower after more than two decades., The plant then dies. The flowering produces, thousands of seeds which results in the slow, , 98, , Environmental Studies for Undergraduate Courses
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regrowth of the bamboo. Bamboo is a favorite, food of elephants and other large herbivores of, the forest such as gaur and deer., Wild relatives of crop plants: All our present, day cultivated varieties of rice, which are grown, for food, come from wild varieties of rice, many, of which have originated in India, China and, Indonesia. Rice forms one of the staple foods of, the world. Although wild varieties are not used, as food crops, they are important as they contain genes, which can be used to develop disease or pest resistance in crops. Many local, varieties of rice have already been lost, as most, farmers now grow only high yielding varieties., , The rare Hangul deer is found only in Kashmir., It has a magnificent spread of antlers with 6, branches on each antler. The Barasingha, or, swamp deer, has wide hoofs that enable this, beautiful animal to live in boggy areas of the, Terai. Each antler has 6 or more branches. The, tiny barking deer lives in many forest areas all, over India. It has two ridges on its face and a, short antler with only 2 branches. Its call sounds, like the bark of a dog., , Blackbuck, , 4.8.2 Common Animal species, , Mammals:, The common deer species found in India include, the sambar, chital, barasingha and barking deer., Sambar live in small family parties especially in, hilly forested areas and feed mainly on shrubs, and leaves of low branches. They are dark brown, in colour and have large thick antlers, each having 3 branches. Chital or spotted deer live in, large herds in forest clearings where they graze, on the grass. They have a rust brown body with, white spots which camouflages them in the forest. Each antler has three branches called tines., , Chinkara, , Nilgai, , Chital, , Barasingha, , Biodiversity, , The blackbuck is the only true antelope found, in India. It lives in large herds. The males are, black on top and cream below and have beautiful spiral horns that form a ‘V’ shape. The, chinkara, also known as the Indian gazelle, is, a smaller animal and is pale brown in colour it, has beautiful curved horns. The rare, Chausingha, or four horned antelope, is the, only animal in the world that has four horns., The nilgai is the largest of the dryland herbi99
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vores. The males are blue-gray. Nilgai have white, markings on the legs and head. They have short, strong spike-like horns., Nilgiri Tahr, , four times a month. Its numbers have declined, due to poaching for its superb skin, and for the, supposed magical value of its teeth, claws and, whiskers. In the recent past it has been extensively killed for the supposed medicinal properties of its bones that are used in Chinese, medicine., The Asiatic lion is now found only in the Gir, forests of Gujarat., , Indian, wild ass, , A very special rare species is the Indian wild, ass, endemic to the Little Rann of Kutch. Himalayan pastures support several species of wild, goats and sheep, many of them restricted to, the region, like the goral and the Himalayan, tahr. A single species, the Nilgiri tahr is found, in the Nilgiri and Annamalai hills in south India., The rhinocerous is now restricted to Assam but, was once found throughout the Gangetic plains., The wild buffalo is now also restricted to the, Terai. The elephant is distributed in the Northeastern and Southern States. It is threatened by, habitat loss and poaching for ivory. Gaur is, found in patches in several well-wooded parts, of India., The best known predator of our forests is the, tiger. Its gold and black stripes hide it perfectly, in the forest undergrowth. It preys on herbivores, such as sambar or chital or less frequently on, domestic animals. The tiger kills only three or, , Tiger, , 100, , The leopard is more adaptable than the tiger, and lives both in thick forests and degraded forest areas. Its beautiful ring like markings camouflage it so perfectly that its prey cannot see, its stealthy approach. The smaller jungle cat,, which is a light brown animal and the leopard, cat, which is a little bigger than a domestic cat,, are very rare. The most typical predator of the, HImalayas is the snow leopard, which is very, rare and poached for its beautiful skin which is, pale grey with dark grey ring-like markings., , Leopard, , Snow Leopard, , The wolf, jackal, fox and the wild dog or, ‘dhole’ form a group called canids. Another, threatened predator is the Himalayan wolf., The wolves are now highly threatened as they, have become increasingly dependent on, shepherd’s flocks. Thus shepherds constantly, find ways to kill the wolves., Environmental Studies for Undergraduate Courses
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Wolf, , be seen in the Western, Ghats. There are several, species of Hornbills that, live on fruit. They have, heavy curved beaks with a, projection on top., Frugivores such as parakeets, barbets and bulbuls live on fruit and are, often seen eating Ficus, fruits such as those of banyan and peepal., Hornbill, , Fox, , Paradise, flycatcher, , Bee-eater, , One of the common monkey species of the forest is the bonnet macaque, which has a red, face, a very long tail and a whorl of hair on the, scalp which looks like a cap. Our other common monkey is the rhesus macaque, which is, smaller and has a shorter tail than the bonnet., A rare macaque is the lion-tailed macaque, found only in a few forests of the southern, Western Ghats and Annamalai ranges. It is black, in colour, has long hair, a grey mane and a tassel at the end of its tail that looks like a lion’s, tail. The common langur has a black face and, is known as the Hanuman monkey. The rare, golden langur, is golden yellow in colour and, lives along the banks of the Manas River in, Assam. The capped langur is an uncommon, species of Northeast India. The rare black nilgiri, langur lives in the southern Western Ghats,, Nilgiris and Annamalais., , Bird of pray, , Birds:, , Insectivorous birds of many species live on forest insects. They include various species of flycatchers, bee-eaters, and others. The male, paradise flycatcher is a small beautiful white bird, with a black head and two long white trailing, tail feathers. The female is brown and does not, have the long tail feathers. There are several, eagles, falcons and kites many of which are now, endangered., , There are over 1200 bird species found in India, in different habitats. Most of our forest birds, are specially adapted to life in certain forest, types. Some Himalayan species however can also, , Grasslands support many species of birds. The, most threatened species is the Great Indian, bustard, a large, brown stately bird with long, legs which struts about through grasslands look-, , Biodiversity, , 101
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Great Indian, Bustard, , Monitor, Lizard, , Reptiles:, India has a wide, variety of lizards,, snakes and turtles,, with a high level of, endemism. The lizards include the, , common garden lizard,, Fan throated, l i z a r d ,, Chamelion,, Skink, Common Monitor and Water Monitor. Some of, these are threatened due to trade in reptile skins., Indian snakes include the Rock Python,, Russell’s viper and the Vine snake. We rarely, appreciate the fact, that only a few spe- Star, cies of snakes are tortoise, poisonous and most, snakes are harmless. The Star tortoise, and, Travancore tortoise are now rare. The Olive Ridley and Flapshell turtle are the well-known turtles of India., Many turtles are becoming increasingly rare due, to poaching of adults and eggs. The crocodile, is our largest reptile, Gharial which is poached for, its prized skin. The, gharial is endemic to, India and is highly, threatened., Fanthroated Lizard, , ing for locusts and grasshoppers. Another rare, group of threatened birds, are the floricans. There are, Partridge, many species of quails,, partridges, larks, munias, and other grain eating birds, that are adapted to grasslands., There are several species of, aquatic birds such as waders,, gulls and terns, which live, along the seashore and go out, Stilt, fishing many kilometers to the, sea. Many of these birds have, lost their coastal habitats due, to pollution. Aquatic birds in, freshwater are those with long legs and are, known as waders such as stilts and sandpipers. The other group form birds that swim on, water such as several species of ducks and, geese., There are many species of, spectacular large birds associated with water or, marshy areas. These include different species of, Flamingo, storks, cranes, spoonbills, flamingo and pelicans. Many aquatic species, are migrants. They breed, in Northern Europe or Siberia and come to India, in thousands during winter., 102, , Amphibia:, Most of the amphibians found in India are frogs, and toads. These include several species like the, Indian Bull frog, Tree frog, etc. These amphibians are mostly found in the hotspots in the, Northeast and the Western Ghats. It is now, thought that global warming and increasing levEnvironmental Studies for Undergraduate Courses
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els of UV radiation may be seriously affecting, amphibian populations in some areas., , Invertebrates:, Snail, , Invertebrates include a variety of taxa that inhabit, both terrestrial and aquatic, ecosystems. Microscopic, animals like protozoa and, zooplankton form the basis of the food chain, in aquatic habitats., Coral is formed by, Crab, colonies of polyp like, animals. Worms, molluscs (snails), spiders,, crabs, jellyfish, octopus are a few of the, better known invertebrates found in India., , There are more than a million insect species on earth, that are known to science., They include grasshoppers, bugs, beetles, ants,, bees, butterflies and, moths. India is rich in its butterfly and moth species., , Spider, , Beetle, , Marine Life:, Marine ecosystems are most frequently associated with fish and crustacea like crabs and, shrimp, which we use as food. The other species that are endangered include the marine, turtles, which are reptiles, and whales that are, mammals. There are a large number of species, of freshwater fish found in our Indian rivers and, lakes that are now threatened by the introduction of fish from abroad as well as due to being, , Marine Life, , Biodiversity, , 103
Page 131 : introduced from one river into another. Fish are, also now seriously affected by pollution. Marine fisheries are being over harvested in our, coastal waters and the fish catch has decreased, seriously over the last few years. Mechanized, boats with giant, small-meshed nets are a major cause of depleting this resource. There are, many endangered fish such as the Mahseer, which once grew to over a meter in length., Many species of marine animals such as the, whales, sharks and dolphins that live in the, Indian Ocean are now threatened by extinction, due to fishing in the deep sea., For further details see:, 1) CD ROM on ‘The Biodiversity of India’, Mapin, Publications, Ahmedabad,
[email protected], , Project Tiger: Project Tiger was launched, by the Government of India with the support of WWF-International in 1973 and was, the first such initiative aimed at protecting, this key species and all its habitats. Project, Tiger was initiated in nine Tiger Reserves in, different ecosystems of the country covering an area of 16339 sq km. By 2001 the, number of Tiger Reserves increased to 27,, covering an area of 37761 sq km. The tiger, count climbed from 268 in 1972 in the nine, Tiger Reserves, to around 1500 in 1997 in, the 23 Tiger Reserves. The Project tiger recognized the fact that tigers cannot be protected in isolation, and that to protect the, tiger, its habitat needed to be protected., , 2) The Book of Indian Animals, SH Prater, BNHS., 3) The Book of Indian Birds, Salim Ali, BNHS., , 4.9 CONSERVATION OF BIODIVERSITY: INSITU AND EX-SITU, 4.9.1 In-situ conservation, Biodiversity at all its levels, genetic species and, as intact ecosystems, can be best preserved insitu by setting aside an adequate representation of wilderness as ‘Protected Areas’. These, should consist of a network of National Parks, and Wildlife Sanctuaries with each distinctive, ecosystem included in the network. Such a network would preserve the total diversity of life, of a region., In the past National Parks and Sanctuaries in, India were notified to preserve major wildlife, species such as tigers, lions, elephants, and deer., The objective of these areas should be expanded, to the preservation of relatively intact natural, ecosystems, where biological diversity – from, microscopic unicellular plants and animals, to, the giant trees and major mammals – can all be, preserved., 104, , Crocodile Conservation: Crocodiles have, been threatened as their skin is used for, making leather articles. This led to the near, extinction of crocodiles in the wild in the, 1960s in India., A Crocodile Breeding and Conservation Program was initiated in 1975 to protect the, remaining population of crocodilians in their, natural habitat and by creating breeding, centers. It is perhaps one of the most successful ex situ conservation breeding projects, in the country., Crocodiles have been extensively bred in over, 30 captive breeding centers, zoos and other, sites where successful breeding takes place., Thousands of crocodiles of all three species, have been bred and restocked in 20 natural, water bodies., , Environmental Studies for Undergraduate Courses
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Project Elephant: Project Elephant was, launched in 1992 to ensure the long-term, survival of a viable population of elephants, in their natural habitats in north and northeastern India and south India. It is being, implemented in 12 States. In spite of this,, our elephant herds are at threat as their habitat is shrinking and their migration routes, are disrupted by human activities., , However species cannot be protected individually as they are all inter dependent on each other., Thus the whole ecosystem must be protected., The biologist’s view point deals with areas that, are relatively species rich, or those where rare,, threatened or endangered species are found,, or those with ‘endemic’ species which are not, found elsewhere. As rare endemic species are, found only in a small area these easily become, extinct due to human activity. Such areas must, be given an added importance as their, biodiversity is a special feature of the region., Animals such as elephants require different types, of habitat to feed in during different seasons., They utilize open grasslands after the rains when, the young grass shoots are highly nutritious. As, the grasses dry, the elephants move into the, forest to feed on foliage from the trees. A Protected Area that is meant to protect elephants, must therefore be large enough and include diverse habitat types to support a complete, complement of inter linked species., Wildlife Sanctuaries and National Parks of, India: There are 589 Protected Areas in India of, which 89 are National Parks and 500 are Wildlife Sanctuaries. They include a variety of ecosystems and habitats. Some have been created, in order to protect highly endangered species, of wild plants and animals found nowhere else, in the world., , Biodiversity, , The Great Himalayan National Park is the, largest sanctuary in this ecosystem and is one, of the last homes of the beautiful snow leopard. Dachigam Sanctuary is the only place, where the rare Hangul or Kashmir stag is found., There are several Sanctuaries in the Terai region,, Kaziranga National Park is the most famous, which has elephant, wild buffalo, gaur, wild, boar, swamp deer, and hog deer, in large numbers, as well as tiger and leopard. Its bird life is, extremely rich and includes ducks, geese, pelicans and storks. The Manas Sanctuary, in addition to the above Terai species, also includes, the rare golden langur and the very rare pygmy, hog, the smallest wild boar in the world. The, florican is found only in a few undisturbed grasslands in the Terai sanctuaries., In the sal forests of Madhya Pradesh, there are, several Protected Areas. Kanha offers a wonderful opportunity to observe wild tigers from, elephant back. It is the only Protected Area in, which a sub species of the Barasingha is found., Bharatpur is one of the most famous water bird, sanctuaries in the world. Thousands of ducks,, geese, herons, and other wading birds can be, seen here. This is the only home of the very rare, Siberian crane which migrates to India every, winter. During the last 20 years, the 30 or 40, Siberian cranes have dwindled to only 2 or 3., During 2002-3 no cranes were seen and it is, possible that this beautiful bird will never again, come to India., In the Thar desert, the wild life is protected in, the Desert National Park. Here large numbers, of black buck, neelgai and chinkara can be seen., The Great Indian Bustard lives in these arid lands., Ranthambor was the most well known sanctuary for observing tigers in the wild till about 3, or 4 years ago. Since then many tigers have been, killed by poachers., , 105
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The Great and the Little Rann of Kutch have, been made into sanctuaries to protect the very, rare wild ass, the flamingo, the star tortoise and, the desert fox., In Gujarat, the Gir Sanctuary protects the last, population of the majestic Asiatic lion. This thorn, and deciduous forest is also the home of large, herds of chital, sambhar, and nilgai., The Sanctuaries of the Western Ghats and associated hill ranges protect some of the most, diverse forest types in the country. The few examples of highly threatened species include the, Malabar giant squirrel, the flying squirrel and a, variety of hill birds, several species of amphibians, reptiles and insects. These regions are also, rich in highly endemic plant life. Sanctuaries such, as Bhimashankar, Koyana, Chandoli and, Radhanagari preserve this rich flora in, Maharashtra, Bandipur, Bhadra, Dandeli,, Nagarhole, etc. in Karnataka, and Eraviculum,, Perambiculum, Periyar, Silent Valley, in, Kerala., In the Nilgiri Hills the rich forest Sanctuaries protect some of the last pockets of the Indian elephant in South India. Examples include, Bandipur, Madhumalai, Wynad and Bhadra., During the last 10 years, a large number of the, great tusker elephants of this region have been, ruthlessly killed for their ivory. Now very few of, these magnificent animals are left in these, jungles., Two important sanctuaries meant for preservation of coastal ecosystems are the Chilka Lake, and Point Calimere. The Sunderbans protect, the largest mangrove delta in India. The Marine National Park in Gujarat protects shallow, areas in the sea, islands, coral reefs and extensive mudflats., Over a hundred Protected Areas have been created in the Andaman and Nicobar Islands to, preserve their very special island ecosystems., 106, , CASE STUDY, Orissa – Olive Ridley Turtles, Every year at Gahirmatha and two other sites, on the Orissa coast, hundreds of thousands, of Olive Ridley turtles congregate on the, beach, between December and April, for, mass nesting. This was the largest nesting, site for the Olive Ridleys in the world. In 1999, by the end of March it was estimated that, around 200,000 turtles had nested at the, Gahirmatha beach. Marine biologists believe, that only one out of every 1000 eggs actually matures into an adult., There are severe threats to these nesting, sites. Shrinking nesting sites, construction of, roads and buildings close to these rookeries, and other infrastructure development, projects hamper nesting. Trawler fishing is, another large threat to the turtles., After its ‘discovery’ in 1974, the beach was, notified as a Sanctuary (the Bhitarkanaika, Sanctuary) and was closed for hunting., Recognising the threats to turtles from fishing by large trawlers, the Orissa Marine Fisheries Regulation Act was passed in 1982. This, Act prohibits trawling within 10 km of the, coastline throughout the state and makes it, mandatory for all trawlers to use Turtle Excluder Devices (TEDs). In 2001, the State Government of Orissa declared that a five month, period between January to May should constitute a no-fishing season for a distance of, 20 km from the coastline., Apart form these initiatives, Operation, Kachhapa is being coordinated by the Wildlife Protection Society of India, Delhi and, Wildlife Society of Orissa with many local, NGOs as partners. The Orissa Forest Department, WII, Dehra Dun and the Coast Guard, are also involved in the Project., Environmental Studies for Undergraduate Courses
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The need for an Integrated Protected Area, System (IPAS): Protected Areas, to be effective, must be established in every biogeographic, region. A relatively larger representation must, be included of highly fragile ecosystems, areas, of high species diversity or high endemism. Protected Areas must also be integrated with each, other by establishing corridors between adjacent areas wherever possible so that wildlife can, move between them., In our country, which has a rapidly growing, human population, it is not easily feasible to set, aside more and more land to create Protected, Areas. The need to provide a greater amount of, land for agricultural and other needs has become an increasing cause of concern in land and, resource management. This forms a major impediment for creating new Protected Areas., Having said this, there is an urgent need to add, to our Protected Areas to preserve our very rich, biological diversity. Much of the natural wilderness has already undergone extensive changes., The residual areas that have high levels of species richness, endemism or endangered plants, and animals must be notified as National Parks, and Wildlife Sanctuaries. Other areas can be, made into Community Conserved Areas which, are managed by local people., The International Union for Conservation of, Nature and Natural Resources states that it is, essential to include at least 10% of all ecosystems as Protected Areas if biodiversity is to be, conserved in the long-term., India has only 5% of land in its 589 Protected, Areas in 2004. However much of this includes, plantations of sal or teak, which were developed for timber in the past and are thus relatively poor in diversity and have a low level of, ‘naturalness’. There are only a few good grasslands left in our country that are notified as Protected Areas. Some are overgrazed wastelands, in areas that were once flourishing grasslands., Most of these areas have a low biological value, Biodiversity, , and need careful management to allow them, to revert to a more ‘natural’ state, with their, full complement of plants and animals. Only a, few wetlands have been made into Sanctuaries. These require better management., A major strategy to reduce impacts on the, biodiversity of the PAs should be to provide a, sustainable source of resources for local people, living around them. A Protected Area curtails, their traditional grazing practices and access, fuelwood sources. These resources must be provided by developing them in buffer areas. Plantations of fuel wood and good grassland, management in areas outside Protected Areas, can help reduce the pressure on the habitat of, wildlife in the Protected Area. Management, must ensure that local people derive a direct, economic benefit from the presence of the PA., Involving local people in Protected Area management and developing tourist facilities that, support the income generation for local people, helps in involving their support for the Protected, Area., A carefully designed management plan which, incorporates an ‘ecodevelopment’ component, aimed at providing a source of fuel wood, fodder and alternate income generation for local, people, is an important aspect of PA management., There are several species of plants and animals, that survive without protection outside our current network of PAs. As it is not practical to, notify more PAs without affecting the lives of, people, alternate strategies such as Community, Reserves or Community Conserved Areas need, to be created. These should be managed by local people to bring about the conservation of, biodiversity while using the area’s resources in, an equitable and sustainable way. A Community Conserved Area must have specific conservation goals that can be achieved without, compromising the area’s utilitarian potential., , 107
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A major drive for conservation of biological diversity can only come from a mass environmental education program on the value of protecting, our dwindling biological resources., , 4.9.2 Ex-situ conservation, Conservation of a species is best done by protecting its habitat along with all the other species that live in it in nature. This is known as, in-situ conservation, which is conserving a species in its own environment by creating National, Parks and Wildlife Sanctuaries. However, there, are situations in which an endangered species, is so close to extinction that unless alternate, methods are instituted, the species may be rapidly driven to extinction. This strategy is known, as ex-situ conservation, i.e. outside its natural, habitat in a carefully controlled situation such, as a botanical garden for plants or a zoological, park for animals, where there is expertise to, multiply the species under artificially managed, conditions. These breeding programs for rare, plants and animals are however more expensive than managing a Protected Area., There is also another form of preserving a plant, by preserving its germ plasm in a gene bank so, that it can be used if needed in future. This is, even more expensive., When an animal is on the brink of extinction, it, must be carefully bred so that inbreeding does, not lead to the genetic makeup becoming weak., Breeding from the same stock can lead to poorly, adapted progeny or even inability to get enough, offspring., Modern breeding programs are done in zoos, that provide for all the animal’s needs, including enclosures that simulate their wild habitats., There may also be a need to assist breeding artificially. Thus while most zoos are meant to provide visitors with a visual experience of seeing a, wild animal close up, and provide the visitors, 108, , with information about the species, a modern, zoo has to go beyond these functions that include breeding of endangered species as a conservation measure., In India, successful ex situ conservation programs, have been done for all our three species of crocodiles. This has been highly successful. Another, recent success has been the breeding of the very, rare pygmy hog in Gauhati zoo. Delhi zoo has, successfully bred the rare Manipur brow antlered deer., However the most important step of a successful breeding program is the reintroduction of a, species into its original wild habitat. This requires, rehabilitation of the degraded habitat and removal of the other causes such as poaching,, disturbance, or other manmade influences that, have been the primary cause of reducing the, population of the species., , Conservation of cultivars and livestock, breeds: There were an estimated thirty thousand varieties of rice grown in India till about 50, years ago. Now only a few of these are still, grown. The new varieties which are now being, cultivated everywhere have been developed, using germ plasm of these original types of rice., If all the traditional varieties vanish completely, it will be difficult to develop new disease resistant varieties of rice in the future. Several varieties have been preserved in gene banks., However, this is both very expensive and risky., Encouraging farmers to continue to grow several traditional varieties is thus an important, concern for the future of mankind. At present, gene bank collections have over 34 thousand, cereals and 22 thousand pulses., , Environmental Studies for Undergraduate Courses
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CASE STUDY, Beej Bachao Andolan (Save the Seeds, Movement), This movement began in the Himalayan foothills. The members have collected seeds of, diverse crops in Garhwal. The movement has, successfully conserved hundreds of local rice, varieties, rajma, pulses, millets, vegetables,, spices and herbs. Many different varieties are, being grown as an outcome of this program, in local farmer’s fields. This has also been, supported by local women’s groups who felt, these varieties were better than those provided by the green revolution. In contrast,, men who were interested in cash returns in, a short time found it difficult to appreciate, the benefits of growing indigenous varieties., , In the past, domestic animals were selected and, bred for their ability to adapt to local conditions., Traditional agropastoralists in India have selectively bred livestock for 2 to 3 thousand years., India has 27 breeds of cattle, 40 breeds of sheep,, 22 breeds of goats, and 8 breeds of buffaloes., These traditional breeds must be maintained for, their genetic variability., , Biodiversity, , 109
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UNIT 5:, , Pollution, , Chapter5.p65, , 5.1 DEFINITION, , 112, , 5.2 CAUSES, EFFECTS AND CONTROL MEASURES OF:, , 113, , 5.2.1 Air Pollution, , 113, , 5.2.2 Water Pollution, , 123, , 5.2.3 Soil Pollution, , 131, , 5.2.4 Marine Pollution, , 135, , 5.2.5 Noise Pollution, , 140, , 5.2.6 Thermal Pollution, , 142, , 5.2.7 Nuclear hazards, , 143, , 5.3 SOLID WASTE MANAGEMENT: CAUSES, EFFECTS AND CONTROL MEASURES, OF URBAN AND INDUSTRIAL WASTE, , 145, , 5.4 ROLE OF INDIVIDUALS IN POLLUTION PREVENTION, , 150, , 5.5 POLLUTION CASE STUDIES, , 153, , 5.6 DISASTER MANAGEMENT: FLOODS, EARTHQUAKES, CYCLONES, LANDSLIDES, , 156, , Pollution, , 111, , 111, , 4/9/2004, 5:09 PM
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‘We spray our elms, and the following spring,, trees are silent of robin song, not because, we sprayed the robins directly but because, the poison traveled step by step through the, now familiar elm-earthworm-robin cycle’, – Rachael Carson, , book has inspired controversy and has initiated, a major change in thinking about the safety of, using pesticides and other toxic chemicals., , This quotation appeared in Rachael Carson’s, book entitled Silent Spring. In the years following the publication of Silent Spring in 1962, the, , Pollution is the effect of undesirable changes in, our surroundings that have harmful effects on, plants, animals and human beings. This occurs, Environmental Studies for Undergraduate Courses, , 112, , Chapter5.p65, , 5.1 DEFINITION, , 112, , 4/9/2004, 5:09 PM
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when only short-term economic gains are made, at the cost of the long-term ecological benefits, for humanity. No natural phenomenon has led, to greater ecological changes than have been, made by mankind. During the last few decades, we have contaminated our air, water and land, on which life itself depends with a variety of, waste products., Pollutants include solid, liquid or gaseous substances present in greater than natural abundance produced due to human activity, which, have a detrimental effect on our environment., The nature and concentration of a pollutant, determines the severity of detrimental effects, on human health. An average human requires, about 12 kg of air each day, which is nearly 12, to15 times greater than the amount of food we, eat. Thus even a small concentration of pollutants in the air becomes more significant in comparison to the similar levels present in food., Pollutants that enter water have the ability to, spread to distant places especially in the marine, ecosystem., From an ecological perspective pollutants can, be classified as follows:, Degradable or non-persistent pollutants: These, can be rapidly broken down by natural processes. Eg: domestic sewage, discarded vegetables, etc., Slowly degradable or persistent pollutants: Pollutants that remain in the environment for many, years in an unchanged condition and take decades or longer to degrade. Eg: DDT and most, plastics., Non-degradable pollutants: These cannot be, degraded by natural processes. Once they are, released into the environment they are difficult, to eradicate and continue to accumulate. Eg:, toxic elements like lead or mercury., , 5.2 CAUSES, EFFECTS AND CONTROL MEASURES OF POLLUTION, 5.2.1 Air Pollution, History of air pollution: The origin of air pollution on the earth can be traced from the times, when man started using firewood as a means, of cooking and heating. Hippocrates has mentioned air pollution in 400 BC. With the discovery and increasing use of coal, air pollution, became more pronounced especially in urban, areas. It was recognized as a problem 700 years, ago in London in the form of smoke pollution,, which prompted King Edward I to make the first, antipollution law to restrict people from using, coal for domestic heating in the year 1273. In, the year 1300 another Act banning the use of, coal was passed. Defying the law led to imposition of capital punishment. In spite of this air, pollution became a serious problem in London, during the industrial revolution due to the use, of coal in industries. The earliest recorded major disaster was the ‘London Smog’ that occurred, in 1952 that resulted in more than 4000 deaths, due to the accumulation of air pollutants over, the city for five days., In Europe, around the middle of the 19th century, a black form of the Peppered moth was, noticed in industrial areas. Usually the normal, Peppered moth is well camouflaged on a clean, lichen covered tree. However the peppered pattern was easily spotted and picked up by birds, on the smoke blackened bark of trees in the, industrial area, while the black form remained, well camouflaged. Thus while the peppered, patterned moths were successful in surviving in, clean non-industrial areas, the black coloured, moths were successful in industrial areas. With, the spread of industrialization, it has been observed that the black forms are not only see in, Peppered moth, but also in many other moths., This is a classic case of pollution leading to adaptation., , Pollution, , Chapter5.p65, , 113, , 113, , 4/9/2004, 5:09 PM
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Air pollution began to increase in the beginning, of the twentieth century with the development, of the transportation systems and large-scale use, of petrol and diesel. The severe air quality problems due to the formation of photochemical, smog from the combustion residues of diesel, and petrol engines were felt for the first time in, Los Angeles. Pollution due to auto-exhaust remains a serious environmental issue in many, developed and developing countries including, India., The Air Pollution Control Act in India was passed, in 1981 and the Motor Vehicle Act for controlling the air pollution, very recently. These laws, are intended to prevent air from being polluted., The greatest industrial disaster leading to serious air pollution took place in Bhopal where, extremely poisonous methyl isocyanide gas was, accidentally released from the Union Carbide’s, pesticide manufacturing plant on the night of, December 3rd 1984. The effects of this disaster, on human health and the soil are felt even today., , Temperature declines with altitude in the troposphere. At the top of the troposphere temperatures abruptly begin to rise. This boundary, where this temperature reversal occurs is called, the tropopause., The tropopause marks the end of the troposphere and the beginning of the stratosphere,, the second layer of the atmosphere. The stratosphere extends from 17 to 48 kilometers above, the earth’s surface. While the composition of, the stratosphere is similar to that of the troposphere it has two major differences. The volume of water vapour here is about 1000 times, less while the volume of ozone is about 1000, times greater. The presence of ozone in the, stratosphere prevents about 99 percent of the, sun’s harmful ultraviolet radiation from reaching the earth’s surface thus protecting humans, from cancer and damage to the immune system. This layer does not have clouds and hence, airplanes fly in this layer as it creates less turbulence. Temperature rises with altitude in the, stratosphere until there is another reversal. This, point is called the stratopause and it marks the, end of the stratosphere and the beginning of, the atmosphere’s next layer, the mesosphere., , Structure of the atmosphere, The atmosphere is normally composed of 79, percent nitrogen, 20 percent oxygen and one, percent as a mixture of carbon dioxide, water, vapour and trace amounts of several other gases, such as neon, helium, methane, krypton, hydrogen and xenon. The general structure of the, atmosphere has several important features that, have relevance to environmental problems. The, atmosphere is divided into several layers., The innermost layer the troposphere extends 17, kilometers above sea level at the equator and, about 8 kilometers over the poles. It contains, about 75 percent of the mass of the earth’s air., The fragility of this layer is obvious from the fact, that if the earth were an apple this particular, layer would be no thicker than an apple’s skin., , Types and sources of Air Pollution, What is air pollution?, Air pollution occurs due to the presence of undesirable solid or gaseous particles in the air in, quantities that are harmful to human health and, the environment. Air may get polluted by natuEnvironmental Studies for Undergraduate Courses, , 114, , Chapter5.p65, , In the mesosphere the temperature decreases, with altitude falling up to –110 oC at the top., Above this is a layer where ionization of the, gases is a major phenomenon, thus increasing, the temperature. This layer is called the thermosphere. Only the lower troposphere is routinely involved in our weather and hence air, pollution. The other layers are not significant in, determining the level of air pollution., , 114, , 4/9/2004, 5:09 PM
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ral causes such as volcanoes, which release ash,, dust, sulphur and other gases, or by forest fires, that are occasionally naturally caused by lightning. However, unlike pollutants from human, activity, naturally occurring pollutants tend to, remain in the atmosphere for a short time and, do not lead to permanent atmospheric change., Pollutants that are emitted directly from identifiable sources are produced both by natural, events (for example, dust storms and volcanic, eruptions) and human activities (emission from, vehicles, industries, etc.). These are called primary pollutants. There are five primary pollutants that together contribute about 90 percent, of the global air pollution. These are carbon, oxides (CO and CO2), nitrogen oxides, sulfur, oxides, volatile organic compounds (mostly hydrocarbons) and suspended particulate matter., Pollutants that are produced in the atmosphere, when certain chemical reactions take place, among the primary pollutants are called secondary pollutants. Eg: sulfuric acid, nitric acid, carbonic acid, etc., , Carbon monoxide is a colourless, odorless and, toxic gas produced when organic materials such, as natural gas, coal or wood are incompletely, burnt. Vehicular exhausts are the single largest, source of carbon monoxide. The number of vehicles has been increasing over the years all over, the world. Vehicles are also poorly maintained, and several have inadequate pollution control, equipment resulting in release of greater, amounts of carbon monoxide. Carbon monoxide is however not a persistent pollutant. Natural processes can convert carbon monoxide to, other compounds that are not harmful. Therefore the air can be cleared of its carbon monoxide if no new carbon monoxide is introduced, into the atmosphere., Sulfur oxides are produced when sulfur containing fossil fuels are burnt., , Nitrogen oxides are found in vehicular exhausts., Nitrogen oxides are significant, as they are involved in the production of secondary air pollutants such as ozone., Hydrocarbons are a group of compounds consisting of carbon and hydrogen atoms. They either evaporate from fuel supplies or are, remnants of fuel that did not burn completely., Hydrocarbons are washed out of the air when, it rains and run into surface water. They cause, an oily film on the surface and do not as such, cause a serious issue until they react to form, secondary pollutants. Using higher oxygen concentrations in the fuel-air mixture and using, valves to prevent the escape of gases, fitting of, catalytic converters in automobiles, are some of, the modifications that can reduce the release, of hydrocarbons into the atmosphere., Particulates are small pieces of solid material (for, example, smoke particles from fires, bits of asbestos, dust particles and ash from industries), dispersed into the atmosphere. The effects of, particulates range from soot to the carcinogenic, (cancer causing) effects of asbestos, dust particles and ash from industrial plants that are dispersed into the atmosphere. Repeated exposure, to particulates can cause them to accumulate, in the lungs and interfere with the ability of the, lungs to exchange gases., Lead is a major air pollutant that remains largely, unmonitored and is emitted by vehicles. High, lead levels have been reported in the ambient, air in metropolitan cities. Leaded petrol is the, primary source of airborne lead emissions in Indian cities., Pollutants are also found indoors from infiltration of polluted outside air and from various, chemicals used or produced inside buildings., Both indoor and outdoor air pollution are equally, harmful., , Pollution, , Chapter5.p65, , 115, , 115, , 4/9/2004, 5:09 PM
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Types of particulates, Term, , Meaning, , Examples, , Aerosol, , General term for particles suspended in air, , Sprays from pressurized cans, , Mist, , Aerosol consisting of liquid droplets, , Sulfuric acid mist, , Dust, , Aerosol consisting of solid particles that are blown into, the air or are produced from larger particles by grinding, them down, , Dust storm, , Smoke, , Aerosol consisting of solid particles or a mixture of solid, and liquid particles produced by chemical reaction such, as fires, , Cigarette smoke, smoke, from burning garbage, , Fume, , Generally means the same as smoke but often applies, specifically to aerosols produced by condensation of hot, vapors of metals., , Zinc/lead fumes, , Plume, , Geometrical shape or form of the smoke coming out of, a chimney, , Fog, , Aerosol consisting of water droplets, , Smog, , Term used to describe a mixture of smoke and fog., , What happens to pollutants in the atmosphere?, Once pollutants enter the troposphere they are, transported downwind, diluted by the large volume of air, transformed through either physical, or chemical changes or are removed from the, atmosphere by rain during which they are attached to water vapour that subsequently forms, rain or snow that falls to the earth’s surface., The atmosphere normally disperses pollutants, by mixing them in the very large volume of air, that covers the earth. This dilutes the pollutants, to acceptable levels. The rate of dispersion however varies in relation to the following aspects:, , However on a still evening, the process is reversed. An hour or two before sunset after a, sunny day, the ground starts to lose heat and, the air near the ground begins to cool rapidly., Due to the absence of wind, a static layer of, cold air is produced as the ground cools. This in, turn induces condensation of fog. The morning, sun cannot initially penetrate this fog layer. The, Environmental Studies for Undergraduate Courses, , 116, , Chapter5.p65, , Topography, Normally as the earth’s surface becomes, warmed by sunlight the layer of air in contact, with the ground is also heated by convection., This warmer air is less dense than the cold air, above it, so it rises. Thus pollutants produced in, the surface layer are effectively dispersed., , 116, , 4/9/2004, 5:09 PM
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cold air being dense cannot rise and is trapped, by the warm air above. It cannot move out of, the area due to the surrounding hills. The topographic features resemble a closed chemical reactor in which the pollutants are trapped. This, condition often continues through the cool night, and reaches its maximum intensity before sunrise. When the morning sun warms the ground, the air near the ground also warms up and rises, within an hour or two. This may be broken up, by strong winds. In cold regions this situation, can persist for several days. Such a situation is, known as smog (smoke + fog)., , other industrial establishments. This used to lead, to the generation of high levels of smoke containing sulphur oxides. Due to a sudden adverse, meteorological condition air pollutants like, smoke and sulphur oxides started to build-up in, the atmosphere. The white fog accumulated, over the city turned black forming a ‘pea-soup’, smog with almost zero visibility. Within two days, of the formation of this smog, people started, suffering from acute pulmonary disorders which, caused irritation of bronchi, cough, nasal discharges, sore throat, vomiting and burning sensations in the eyes. This event lead to several, deaths., , Meteorological conditions, The velocity of the wind affects the dispersal of, pollutants. Strong winds mix polluted air more, rapidly with the surrounding air diluting the, pollutants rapidly. When wind velocity is low, mixing takes place and the concentration of, pollutants remains high., , The most well known example is that of the, ‘London Smog’ that occurred in 1952. The city, used large quantities of sulphur containing coal, for domestic heating that released smoke, along, with smoke from thermal power plants and, Pollution, , Chapter5.p65, , 117, , 117, , 4/9/2004, 5:09 PM
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When sulphur dioxide and nitrogen oxides are, transported by prevailing winds they form secondary pollutants such as nitric acid vapour,, droplets of sulfuric acid and particles of sulphate, and nitrate salts. These chemicals descend on, the earth’s surface in two forms: wet (as acidic, rain, snow, fog and cloud vapour) and dry (as, acidic particles). The resulting mixture is called, acid deposition, commonly called acid rain., Acid deposition has many harmful effects especially when the pH falls below 5.1 for terrestrial, systems and below 5.5 for aquatic systems. It, contributes to human respiratory diseases such, as bronchitis and asthma, which can cause premature death. It also damages statues, buildings, metals and car finishes. Acid deposition, can damage tree foliage directly but the most, serious effect is weakening of trees so they become more susceptible to other types of damage. The nitric acid and the nitrate salts in acid, deposition can lead to excessive soil nitrogen, levels. This can over stimulate growth of other, plants and intensify depletion of other important soil nutrients such as calcium and magnesium, which in turn can reduce tree growth and, vigour., , Effects of air pollution on living organisms, Our respiratory system has a number of mechanisms that help in protecting us from air pollution. The hair in our nose filters out large, particles. The sticky mucus in the lining of the, upper respiratory tract captures smaller particles, and dissolves some gaseous pollutants. When, the upper respiratory system is irritated by pollutants sneezing and coughing expel contaminated air and mucus. Prolonged smoking or, exposure to air pollutants can overload or breakdown these natural defenses causing or contributing to diseases such as lung cancer,, asthma, chronic bronchitis and emphysema. Elderly people, infants, pregnant women and, people with heart disease, asthma or other res-, , Cigarette smoking is responsible for the greatest exposure to carbon monoxide. Exposure to, air containing even 0.001 percent of carbon, monoxide for several hours can cause collapse,, coma and even death. As carbon monoxide remains attached to hemoglobin in blood for a, long time, it accumulates and reduces the oxygen carrying capacity of blood. This impairs perception and thinking, slows reflexes and causes, headaches, drowsiness, dizziness and nausea., Carbon monoxide in heavy traffic causes headaches, drowsiness and blurred vision., Sulfur dioxide irritates respiratory tissues., Chronic exposure causes a condition similar to, bronchitis. It also reacts with water, oxygen and, other material in the air to form sulfur-containing acids. The acids can become attached to, particles which when inhaled are very corrosive, to the lung., Nitrogen oxides especially NO2 can irritate the, lungs, aggravate asthma or chronic bronchitis, and also increase susceptibility to respiratory, infections such as influenza or common colds., Suspended particles aggravate bronchitis and, asthma. Exposure to these particles over a long, period of time damages lung tissue and contributes to the development of chronic respiratory disease and cancer., Many volatile organic compounds such as (benzene and formaldehyde) and toxic particulates, (such as lead, cadmium) can cause mutations,, reproductive problems or cancer. Inhaling ozone,, a component of photochemical smog causes, coughing, chest pain, breathlessness and irritation of the eye, nose and the throat., , Environmental Studies for Undergraduate Courses, , 118, , Chapter5.p65, , piratory diseases are especially vulnerable to air, pollution., , 118, , 4/9/2004, 5:09 PM
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centration can produce dramatic effects on life, on earth., , Effects on plants, When some gaseous pollutants enter leaf pores, they damage the leaves of crop plants. Chronic, exposure of the leaves to air pollutants can break, down the waxy coating that helps prevent excessive water loss and leads to damage from, diseases, pests, drought and frost. Such exposure interferes with photosynthesis and plant, growth, reduces nutrient uptake and causes, leaves to turn yellow, brown or drop off altogether. At a higher concentration of sulphur, dioxide majority of the flower buds become stiff, and hard. They eventually fall from the plants,, as they are unable to flower., Prolonged exposure to high levels of several air, pollutants from smelters, coal burning power, plants and industrial units as well as from cars, and trucks can damage trees and other plants., , Effects of air pollution on materials, Every year air pollutants cause damage worth, billions of rupees. Air pollutants break down, exterior paint on cars and houses. All around, the world air pollutants have discoloured irreplaceable monuments, historic buildings, marble, statues, etc., , Effects of air pollution on the stratosphere, The upper stratosphere consists of considerable, amounts of ozone, which works as an effective, screen for ultraviolet light. This region called the, ozone layer extends up to 60 kms above the, surface of the earth. Though the ozone is, present upto 60 kms its greatest density remains, in the region between 20 to 25 kms. The ozone, layer does not consist of solely ozone but a mixture of other common atmospheric gases. In the, most dense ozone layer there will be only one, ozone molecule in 100,000 gas molecules., Therefore even small changes in the ozone con-, , The total amount of ozone in a ‘column’ of air, from the earth’s surface upto an altitude of 50, km is the total column ozone. This is recorded, in Dobson Units (DU), a measure of the thickness of the ozone layer by an equivalent layer, of pure ozone gas at normal temperature and, pressure at sea level. This means that 100, DU=1mm of pure ozone gas at normal temperature and pressure at sea level., Ozone is a form of oxygen with three atoms, instead of two. It is produced naturally from the, photodissociation of oxygen gas molecules in, the atmosphere. The ozone thus formed is constantly broken down by naturally occurring processes that maintain its balance in the ozone, layer. In the absence of pollutants the creation, and breakdown of ozone are purely governed, by natural forces, but the presence of certain, pollutants can accelerate the breakdown of, ozone. Though it was known earlier that ozone, shows fluctuations in its concentrations which, may be accompanied sometimes with a little, ozone depletion, it was only in 1985 that the, large scale destruction of the ozone also called, the Ozone Hole came into limelight when some, British researchers published measurements, about the ozone layer., Soon after these findings a greater impetus was, given to research on the ozone layer, which, convincingly established that CFC’s were leading to its depletion. These CFCs (chloro-flurocarbons) are extremely stable, non-flammable,, non-toxic and harmless to handle. This makes, them ideal for many industrial applications like, aerosols, air conditioners, refrigerators and fire, extinguishers. Many cans, which give out foams, and sprays, use CFCs. (eg: perfumes, room fresheners, etc.) CFCs are also used in making foams, for mattresses and cushions, disposable, Styrofoam cups, glasses, packaging material for, insulation, cold storage etc. However their sta-, , Pollution, , Chapter5.p65, , 119, , 119, , 4/9/2004, 5:09 PM
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bility also gives them a long life span in the atmosphere., Halons are similar in structure to the CFCs but, contain bromine atoms instead of chlorine. They, are more dangerous to the ozone layer than, CFCs. Halons are used as fire extinguishing, agents as they do not pose a harm to people, and equipment exposed to them during fire, fighting., The CFCs and the halons migrate into the upper atmosphere after they are released. As they, are heavier than air they have to be carried by, air currents up to just above the lower atmosphere and then they slowly diffuse into the, upper atmosphere. This is a slow process and, can take as long as five to fifteen years. In the, stratosphere unfiltered UV-radiation severs the, chemical bonds releasing chlorine from the rest, of the CFC. This attacks the ozone molecule, resulting in its splitting into an oxygen molecule, and an oxygen atom., Despite the fact that CFCs are evenly distribute, over the globe, the ozone depletion is especially, pronounced over the South Pole due to the extreme weather conditions in the Antarctic atmosphere. The presence of the ice crystals, makes the Cl-O bonding easier. The ozone layer, over countries like Australia, New Zealand, South, Africa and parts of South America is also depleted., India has signed the Montreal Protocol in 1992,, which aims to control the production and consumption of Ozone Depleting Substances., , Ozone depletion-What does it do?, Changes in the ozone layer have serious implications for mankind., Effects on human health: Sunburn, cataract,, aging of the skin and skin cancer are caused by, , Food production: Ultra violet radiation affects, the ability of plants to capture light energy during the process of photosynthesis. This reduces, the nutrient content and the growth of plants., This is seen especially in legumes and cabbage., Plant and animal planktons are damaged by ultra-violet radiation. In zooplanktons (microscopic, animals) the breeding period is shortened by, changes in radiation. As planktons form the basis, of the marine food chain a change in their number and species composition influences fish and, shell fish production., Effect on materials: Increased UV radiation, damages paints and fabrics, causing them to, fade faster., Effect on climate: Atmospheric changes induced by pollution contribute to global warming, a phenomenon which is caused due to the, increase in concentration of certain gases like, carbon dioxide, nitrogen oxides, methane and, CFCs. Observations of the earth have shown, beyond doubt that atmospheric constituents, such as water vapour, carbon dioxide, methane,, nitrogen oxides and Chloro Fluro Carbons trap, heat in the form of infra-red radiation near the, earth’s surface. This is known as the ‘Greenhouse Effect’. The phenomenon is similar to, what happens in a greenhouse. The glass in a, greenhouse allows solar radiation to enter which, is absorbed by the objects inside. These objects, radiate heat in the form of terrestrial radiation,, which does not pass out through the glass. The, heat is therefore trapped in the greenhouse increasing the temperature inside and ensuring, the luxuriant growth of plants., Environmental Studies for Undergraduate Courses, , 120, , Chapter5.p65, , increased ultra-violet radiation. It weakens the, immune system by suppressing the resistance, of the whole body to certain infections like, measles, chicken pox and other viral diseases, that elicit rash and parasitic diseases such as, malaria introduced through the skin., , 120, , 4/9/2004, 5:09 PM
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Green House Effect, , There could be several adverse effects of global, warming., •, , With a warmer earth the polar ice caps will, melt causing a rise in ocean levels and flooding of coastal areas., , •, , In countries like Bangladesh or the Maldives, this would be catastrophic. If the sea level, rises by 3m., Maldives will disappear completely beneath the waves., , ane are trapped beneath the frozen soil of, Alaska. When the permafrost melts the, methane that will be released can accelerate the process of global warming., , Control measures for air pollution, , •, , The rise in temperature will bring about a, fall in agricultural produce., , •, , Changes in the distribution of solar energy, can bring about changes in habitats. A previously productive agricultural area will suffer severe droughts while rains will fall in, locations that were once deserts. This could, bring about changes in the species of natural plants, agricultural crops, insects, livestock and micro-organisms., , •, , In the polar regions temperature rises, caused by global warming would have disastrous effects. Vast quantities of meth-, , Air pollution can be controlled by two fundamental approaches: preventive techniques and, effluent control., One of the effective means of controlling air, pollution is to have proper equipment in, place. This includes devices for removal of pollutants from the flue gases though scrubbers,, closed collection recovery systems through, which it is possible to collect the pollutants, before they escape, use of dry and wet collectors, filters, electrostatic precipitators, etc., Providing a greater height to the stacks can, help in facilitating the discharge of pollutants, as far away from the ground as possible. Industries should be located in places so as to minimize the effects of pollution after considering, the topography and the wind directions., Substitution of raw material that causes more, , Pollution, , Chapter5.p65, , 121, , 121, , 4/9/2004, 5:09 PM
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pollution with those that cause less pollution can, be done., , Air pollution in India, The World health Organization (WHO) which, rates only mega cities of the world has rated, Delhi the fourth most polluted city ion the world., However compared to other cities in India, Delhi, is not at the top of the list of polluted cities. Our, country has several pollution hotspots. The recent release from the Central Pollution Control, Board (CPCB), Parivesh, January 2003 states that, Ahmedabad’s air is most noxious flowed by, Kanpur, Solapur and Lucknow with small particulate levels (PM10) 3-4 times the standard of, 60 microgram per cubic meter (mg/m3). The report has ranked 29 cities according to Respirable Particulate Matter (RSPM) levels recorded, during the year 2000. This report thus confirms, the fact that Indian cities show high particulate, pollution with 14 cities hitting critical levels., Nitrogen dioxide levels in most major cities are, generally close to the acceptable annual standard of 60 mg/m3. However sharp increases have, been noticed in a few cities with heavy vehicular traffic and density as in a few locations in, Kolkata and Delhi indicating stronger impact of, traffic. The CPCB indicates vehicles as one of, the predominant sources of air pollution. However the impact of hard measures implemented, in Delhi over the last few years such as introduction of Euro II standards, lowering the sulphur content in fuel to 500 ppm and, implementing Compressed Natural Gas program, has succeeded in improving the quality of air., Rapid urbanization of smaller cities especially, those situated near the big commercial centers, have an enormous increase in traffic load especially in the most polluted segment such as two, and three wheelers and diesel vehicles combined, with poor quality fuel contribute to the deteriorating air quality in a big way., , The Supreme Court also played a vital role protecting the Taj Mahal. Being exposed to sulphur, dioxide and suspended particulate matter, the, Taj had contracted ‘marble cancer’, a fungal, growth that corroded its surface giving it a yellowish tinge. The SPM deposits blackened it. Shri, MC Mehta an environmental lawyer filed a public interest litigation in 1984 expressing concern, over the havoc the polluting units in Agra were, wreaking on the Taj Mahal. Twelve years later, the Supreme Court ordered 292 industries in, the vicinity to either adopt pollution control, measures or shut down. It also made it mandatory for these units to either switch over to ecofriendly fuels like natural gas or shift out of the, area., , Air quality monitoring, India does not presently have a well established, system of monitoring air pollution. When air, quality monitoring began in India in the late, 1960s planners focused only on a few pollutants namely sulphur dioxide, nitrogen oxides and, suspended particulate matter. Other pollutants, such as carbon monoxide and lead were monitored only on a limited scale. The threat from, other air toxins such as benzene, ozone, other, small particulates is not known as these are not, monitored at all. A database on ambient air, quality in Indian cities has been prepared by the, monitoring networks of the National Environmental Engineering Research Institute (NEERI),, Nagpur. The Central Pollution Control Board, (CPCB) initiated its own national Ambient Air, Quality Monitoring (NAAQM) program in 1985., Environmental Studies for Undergraduate Courses, , 122, , Chapter5.p65, , It is alarming to note that residential locations, in India are fast outpacing industrial locations in, air pollution implying that vehicular fumes are, responsible for this trend. The Supreme Court’s, order of April 5, 2002 has directed the Central, Government for an action plan for other polluted cities. Absence of any local initiatives for, action and delay in air pollution control measures will only make the situation worse., , 122, , 4/9/2004, 5:09 PM
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Ambient air quality standards in India developed by the Central Pollution Control Board, Area Category, , SPM µg/m3, , SO2 µg/m3, , Co µg/m3, , NOx µg/m3, , Industrial and mixed use, , 500, , 120, , 5000, , 120, , Residential and rural, , 200, , 80, , 2000, , 80, , Sensitive, , 100, , 3, , 1000, , 30, , Data to the NAAQM is supplied by the respective state pollution control boards, which is then, transmitted to the CPCB. Experts feel that the, present air quality-monitoring network cannot, capture the true profile of urban air pollution, due to the lack of adequate monitoring stations., Moreover critical toxins have still not been included in the list of pollutants to be monitored., , Legal aspects of air pollution control in India, The Air (Prevention and Control of Pollution) Act, was legislated in 1981. The Act provided for, prevention, control and abatement of air pollution. In areas notified under this Act no industrial pollution causing activity could come up, without the permission of the concerned State, Pollution Control Board. But this Act was not, strong enough to play a precautionary or a corrective role. After the Bhopal disaster, a more, comprehensive Environment Protection Act, (EPA) was passed in 1986. This Act for the first, time conferred enforcement agencies with necessary punitive powers to restrict any activity that, can harm the environment. To regulate vehicular pollution the Central Motor Vehicles Act of, 1939 was amended in 1989. Following this, amendment the exhaust emission rules for vehicle owners were notified in 1990 and the mass, emission standards for vehicle manufacturers, were enforced in 1991 for the first time. The, mass emission norms have been further revised, for 2000., , Air quality management as a well-defined program has yet to emerge in India. We need a, much more strengthened air quality management with continuous monitoring of air if we, are to have a better quality of air. This would, also need an integrated approach with strict air, pollution control laws. Some of the suggestions, for doing this include:, •, , Putting a greater emphasis on pollution prevention rather than control, , •, , Reducing the use of fossil fuels, , •, , Improving the quality of vehicular fuel, , •, , Increasing the use of renewable energy, , 5.2.2 Water Pollution, Our liquid planet glows like a soft blue sapphire in the hard-edged darkness of space., There is nothing else like it in the solar system. It is because of water., – John Todd, Introduction: Water is the essential element, that makes life on earth possible. Without water there would be no life. We usually take water for granted. It flows from our taps when they, are turned on. Most of us are able to bathe when, we want to, swim when we choose and water, , Pollution, , Chapter5.p65, , 123, , 123, , 4/9/2004, 5:09 PM
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our gardens. Like good health we ignore water, when we have it., Although 71% of the earth’s surface is covered, by water only a tiny fraction of this water is available to us as fresh water. About 97% of the, total water available on earth is found in oceans, and is too salty for drinking or irrigation. The, remaining 3% is fresh water. Of this 2.997% is, locked in ice caps or glaciers. Thus only 0.003%, of the earth’ total volume of water is easily available to us as soil moisture, groundwater, water, vapour and water in lakes, streams, rivers and, wetlands., In short if the world’s water supply were only, 100 litres our usable supply of fresh water would, be only about 0.003 litres (one-half teaspoon)., This makes water a very precious resource. The, future wars in our world may well be fought, over water. By the middle of this century, almost twice as many people will be trying to share, the same amount of fresh water the earth has, today. As freshwater becomes more scarce access to water resources will be a major factor in, determining the economic growth of several, countries around the world., Water availability on the planet: Water that, is found in streams, rivers, lakes, wetlands and, artificial reservoirs is called surface water. Water that percolates into the ground and fills the, pores in soil and rock is called groundwater., Porous water-saturated layers of sand, gravel, or bedrock through which ground water flows, are called aquifers. Most aquifers are replenished naturally by rainfall that percolates downward through the soil and rock. This process is, called natural recharge. If the withdrawal rate, of an aquifer exceeds its natural recharge rate,, the water table is lowered. Any pollutant that is, discharged onto the land above is also pulled, into the aquifer and pollutes the groundwater, resulting in polluted water in the nearby wells., , When the quality or composition of water, changes directly or indirectly as a result of, man’s activities such that it becomes unfit, for any purpose it is said to be polluted., Point sources of pollution: When a source of, pollution can be readily identified because it has, a definite source and place where it enters the, water it is said to come from a point source., Eg. Municipal and Industrial Discharge Pipes., When a source of pollution cannot be readily, identified, such as agricultural runoff, acid rain,, etc, they are said to be non-point sources of, pollution., , Environmental Studies for Undergraduate Courses, , 124, , Chapter5.p65, , India receives most of her rainfall during the, months of June to September due to the seasonal winds and the temperature differences, between the land and the sea. These winds blow, from the opposite directions in the different seasons. They blow into India from the surrounding oceans during the summer season and blow, out from the subcontinent to the oceans during, the winter. The monsoon in India is usually reasonably stable but varies geographically. In some, years the commencement of the rains may be, delayed considerably over the entire country or, a part of it. The rains may also terminate earlier, than usual. They may be heavier than usual over, one part than over another. All these may cause, local floods or drought. However in India even, areas that receive adequate rainfall during the, monsoon suffer from water shortages in the post, monsoon period due to lack of storage facilities., , 124, , 4/9/2004, 5:09 PM
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Sources of Pollution, , Causes of water pollution, There are several classes of common water pollutants. These are disease-causing agents, (pathogens) which include bacteria, viruses, protozoa and parasitic worms that enter water from, domestic sewage and untreated human and, animal wastes. Human wastes contain concentrated populations of coliform bacteria such as, Escherichia coli and Streptococcus faecalis. These, bacteria normally grow in the large intestine of, humans where they are responsible for some, food digestion and for the production of vitamin K. These bacteria are not harmful in low, numbers. Large amounts of human waste in, water, increases the number of these bacteria, which cause gastrointestinal diseases. Other, potentially harmful bacteria from human wastes, may also be present in smaller numbers. Thus, the greater the amount of wastes in the water, the greater are the chances of contracting diseases from them., Another category of water pollutants is oxygen depleting wastes. These are organic, wastes that can be decomposed by aerobic (oxygen requiring) bacteria. Large populations of, bacteria use up the oxygen present in water to, , degrade these wastes. In the process this degrades water quality. The amount of oxygen, required to break down a certain amount of, organic matter is called the biological oxygen, demand (BOD). The amount of BOD in the water is an indicator of the level of pollution. If too, much organic matter is added to the water all, the available oxygen is used up. This causes fish, and other forms of oxygen dependent aquatic, life to die. Thus anaerobic bacteria (those that, do not require oxygen) begin to break down, the wastes. Their anaerobic respiration produces, chemicals that have a foul odour and an unpleasant taste that is harmful to human health., A third class of pollutants are inorganic plant, nutrients. These are water soluble nitrates and, phosphates that cause excessive growth of algae and other aquatic plants. The excessive, growth of algae and aquatic plants due to added, nutrients is called eutrophication. They may interfere with the use of the water by clogging, water intake pipes, changing the taste and, odour of water and cause a buildup of organic, matter. As the organic matter decays, oxygen, levels decrease and fish and other aquatic species die., , Pollution, , Chapter5.p65, , 125, , 125, , 4/9/2004, 5:09 PM
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The quantity of fertilizers applied in a field is, often many times more than is actually required, by the plants. The chemicals in fertilizers and, pesticides pollute soil and water. While excess, fertilizers cause eutrophication, pesticides cause, bioaccumulation and biomagnification. Pesticides which enter water bodies are introduced, into the aquatic food chain. They are then absorbed by the phytoplanktons and aquatic, plants. These plants are eaten by the herbivorous fish which are in turn eaten by the carnivorous fish which are in turn eaten by the water, birds. At each link in the food chain these chemicals which do not pass out of the body are accumulated and increasingly concentrated, resulting in biomagnification of these harmful, substances., , A fourth class of water pollutants is water, soluble inorganic chemicals which are acids,, salts and compounds of toxic metals such as, mercury and lead. High levels of these chemicals can make the water unfit to drink, harm, , Environmental Studies for Undergraduate Courses, , 126, , Chapter5.p65, , One of the effects of accumulation of high levels of pesticides such as DDT is that birds lay, eggs with shells that are much thinner than, normal. This results in the premature breaking, of these eggs, killing the chicks inside. Birds of, prey such as hawks, eagles and other fish eating birds are affected by such pollution. Although DDT has been banned in India for, agricultural use and is to be used only for malaria eradication, it is still used in the fields as it, is cheap., , 126, , 4/9/2004, 5:09 PM
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fish and other aquatic life, reduce crop yields, and accelerate corrosion of equipment that use, this water., Another cause of water pollution is a variety of, organic chemicals, which include oil, gasoline,, plastics, pesticides, cleaning solvents, detergent, and many other chemicals. These are harmful, to aquatic life and human health. They get into, the water directly from industrial activity either, from improper handling of the chemicals in industries and more often from improper and illegal disposal of chemical wastes., Sediment of suspended matter is another, class of water pollutants. These are insoluble particles of soil and other solids that become suspended in water. This occurs when soil is eroded, from the land. High levels of soil particles suspended in water, interferes with the penetration of sunlight. This reduces the photosynthetic, activity of aquatic plants and algae disrupting, the ecological balance of the aquatic bodies., When the velocity of water in streams and rivers decreases the suspended particles settle, down at the bottom as sediments. Excessive, sediments that settle down destroys feeding and, spawning grounds of fish, clogs and fills lakes,, artificial reservoirs etc., Water soluble radioactive isotopes are yet, another source of water pollution. These can, be concentrated in various tissues and organs, as they pass through food chains and food webs., Ionizing radiation emitted by such isotopes can, cause birth defects, cancer and genetic damage., Hot water let out by power plants and industries that use large volumes of water to cool the, plant result in rise in temperature of the local, water bodies. Thermal pollution occurs when, industry returns the heated water to a water, source. Power plants heat water to convert it, into steam, to drive the turbines that generate, electricity. For efficient functioning of the steam, , turbines, the steam is condensed into water after it leaves the turbines. This condensation is, done by taking water from a water body to absorb the heat. This heated water, which is at, least 15oC higher than the normal is discharged, back into the water body. The warm water not, only decreases the solubility of oxygen but, changes the breeding cycles of various aquatic, organisms., Oil is washed into surface water in runoff from, roads and parking lots which also pollutes, groundwater. Leakage from underground tanks, CASE STUDY, One of the worst oil spill disasters that have, occurred is that of the Exxon Valdez. On 24th, march 1989 the Exxon Valdez, a tanker more, than three football fields wide went off, course in a 16 kilometer wide channel in, Prince William Sound near Valdez in Alaska., It hit submerged rocks, creating an environmental disaster. The rapidly spreading oil slick, coated more than 1600 kilometers of shoreline killing between 300,000 and 645,000, water birds and a large number of sea otters, harbor seals, whales and fishes. Exxon, spent $ 2.2. billion directly on the clean-up, operations. However some results of the, cleanup effort showed that where high pressure jets of hot water were used to clean, beaches coastal plants and animals that had, survived the spill were killed. Thus it did more, harm than good. Exxon pleaded guilty in, 1991 and agreed to pay the Federal Government and the state of Alaska $ 1 billion, in fines and civil damages. This $8.5 billion, accident might have been prevented if Exxon, had spent only $22.5 million to fit the tanker, with a double hull-one inside the other. Such, double hulled vessels would be less likely to, rupture and spill their contents. The spill highlighted the need for marine pollution prevention., , Pollution, , Chapter5.p65, , 127, , 127, , 4/9/2004, 5:09 PM
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is another source of pollution. Accidental oil spills, from large transport tankers at sea have been, causing significant environmental damage., , •, , Leakage from underground storage tanks, containing gasoline and other hazardous, substances, , Though accidents such as the Exxon Valdez get, worldwide attention, much more oil is released, as a result of small, regular releases from other, less visible sources. Nearly two thirds of all marine oil pollution comes from three sources: runoff from streets, improper discharge of, lubricating oil from machines or automobile, crankcases and intentional oil discharges that, occur during the loading and unloading of tankers. Oil tankers often use sea water as ballast to, stabilize the ship after they have discharged their, oil. This oil contaminated water is then discharged back into the sea when the tanker is, refilled., , •, , Leachate from landfills, , •, , Poorly designed and inadequately maintained septic tanks, , •, , Mining wastes, , Groundwater pollution: While oil spills are, highly visible and often get a lot of media attention, a much greater threat to human life, comes from our groundwater being polluted, which is used for drinking and irrigation. While, groundwater is easy to deplete and pollute it, gets renewed very slowly and hence must be, used judiciously. Groundwater flows are slow, and not turbulent hence the contaminants are, not effectively diluted and dispersed as compared to surface water. Moreover pumping, groundwater and treating it is very slow and, costly. Hence it is extremely essential to prevent, the pollution of groundwater in the first place., Ground water is polluted due to:, •, , Urban run-off of untreated or poorly treated, waste water and garbage, , •, , Industrial waste storage located above or, near aquifers, , •, , Agricultural practices such as the application of large amounts of fertilizers and pesticides, animal feeding operations, etc. in, the rural sector, , There are two theories that have been put forth, to explain this unusually high content of arsenic, in groundwater. One group of researchers suggested that the cause is natural while the other, stated that the cause is man-made., According to the first hypothesis, arsenic probably originates in the Himalayan headwaters of, the Ganga and the Brahmaputra rivers and has, been lying undisturbed beneath the surface of, Environmental Studies for Undergraduate Courses, , 128, , Chapter5.p65, , Severe cases of arsenic poisoning from contaminated groundwater have been reported from, West Bengal in what is known today as the worst, case of groundwater pollution. The School of, Environmental Sciences, Jadhavpur University,, West Bengal has been involved in the task of, surveying the magnitude of the arsenic problem in West Bengal for the last fourteen years., According to a report in the Down to Earth (Vol., 11, No.22), arsenic poisoning was first noticed, by K C Saha, former professor of dermatology, at the School of Tropical Medicine, Kolkata when, he began to receive patients with skin lesions, that resembled the symptoms of leprosy which, was in reality not leprosy. Since all the patients, were from the district of 24-Parganas, Saha, along with others began to look for the cause, and found it to be arsenic toxicity. Thus groundwater arsenic contamination in West Bengal was, first reported in a local daily newspaper in December 1983 when 63 people from three villages located in different districts were identified, by health officials as suffering from arsenic poisoning., , 128, , 4/9/2004, 5:09 PM
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the region’s deltas for thousands of years in the, thick layers of fine alluvial mud across the banks, of these rivers. Most of the arsenic affected areas of West Bengal lie in the alluvial plains, formed in the quarternary period (last 1.6 million years).The Purulia district of West Bengal is, part of the extensive area of the Precambrian, era (last 570 million year) having metamorphic, rocks and granites with widespread sulphide, mineralisation. Researchers from the UK based, British Geological Survey (BGS) suggested that, their position close to where the river Ganga, enters Bangladesh (geologically) may be the primary source of arsenic in the Bengal alluvium., According to David Kinniburgh project leader, with BGS the main factor is time. The mud in, these areas is thicker, wider and flatter than almost anywhere else on earth. It can thus take, hundreds or thousands of years for underground, water to percolate through the mud before, reaching the sea and thus it absorbs arsenic for, a long period., Other researchers feel that the excess amount, of arsenic in groundwater can be contributed, to by the high rate of groundwater extraction., Their hypothesis called the pyrite oxidation thesis describes how arsenic can get mobilized in, the groundwater. In this hypothesis arsenic is, assumed to be present in certain minerals (pyrites) that are deposited within the aquifer sediments. Due to the lowering of the water table, below the deposits, arseno-pyrite which is oxidized in a zone of the aquifer called the Vadose, zone releases arsenic as arsenic adsorbed on iron, hydroxide. During the subsequent recharge period, iron hydroxide releases arsenic into groundwater. This theory is supported by two, arguments. The first is the intensive irrigation, development in West Bengal using deep tube, wells and shallow tube wells. This method of, extraction, which was exactly in the 20m to, 100m below ground level ensured, increased, contribution of groundwater to irrigation. The, other argument that supports the pyrite oxidation theory is that prior to irrigation develop-, , ment and drinking water supply schemes based, on groundwater there were no reported cases, of arsenic poisoning., Arsenicosis or arsenic toxicity develops after two, to five years of exposure to arsenic contaminated, drinking water depending on the amount of, water consumption and the arsenic concentration in water. Initially the skin begins to darken, (called diffuse melanosis) which later leads to, spotted melanosis when darkened sports begin, to appear on the chest, back and limbs. At a, later stage leucomelanosis sets in and the body, begins to show black and white spots. In the, middle stage of arsenicosis the skin in parts becomes hard and fibrous. Rough, dry skin with, nodules on hands or the soles of feet indicate, severe toxicity. This can lead to the formation, of gangrene and cancer. Arsenic poisoning, brings with it other complications such as liver, and spleen enlargement, cirrhosis of the liver,, diabetes, goiter and skin cancers., , The state of India’s rivers, India has always had a tradition of worshipping, rivers. Most of the rivers in India are named after gods, goddesses or saints. However a large, majority of the Indian population including those, who worship the rivers do not think twice before polluting a river. Urbanization, industrialization, excess withdrawal of water, agricultural, run-off, improper agricultural practices and various religious and social practices all contribute, to river pollution in India. Every single river in, India be it the Ganga, Yamuna, Cauvery or the, Krishna have their own share of problems due, to pollution. Waters from the Ganga and the, Yamuna are drawn for irrigation through the, network of canals as soon as these rivers reach, the plains reducing the amount of water that, flows downstream. What flows in the river is, water from small nalas, and streams that carry, with them sewage and industrial effluents. The, residual freshwater, is unable to dilute the pol-, , Pollution, , Chapter5.p65, , 129, , 129, , 4/9/2004, 5:09 PM
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lutants and the rivers turn into stinking sewers., In spite of data from scientifically competent, studies conducted by the Central Pollution Control Board (CPCB), the Government has not been, able to tackle this issue. Sewage and municipal, effluents account for 75% of the pollution load, in rivers while the remaining 25% is from industrial effluents and non-point pollution, sources., In 1985, India launched the Ganga Action plan, (GAP) the largest ever river clean-up operation, in the country. The plan has been criticized for,, overspending and slow progress. The GAP Phase, II in 1991 included cleaning operations for the, tributaries of the Ganga, ie; the Yamuna, Gomti, and the Damodar. Thus the Yamuna Action Plan, (YAP), Gomti Action Plan and the Damodar Action plan were added., In 1995 the National River Conservation plan, was launched. Under this all the rivers in India, were taken up for clean-up operations. In most, of these plans, attempts have been made to tap, drains, divert sewage to sewage treatment, plants before letting out the sewage into the, rivers. The biggest drawback of these river cleaning programs was that they failed to pin responsibilities as to who would pay for running the, treatment facilities in the long run. With the, power supply being erratic and these plants, being heavily dependent on power, most of, these facilities lie underutilized. Moreover the, problem of river pollution due to agricultural runoff has not been addressed in these programs., NRCP is scheduled to be completed by March, 2005. The approved cost for the plan is Rs., 772.08 crores covering 18 rivers in 10 states including 46 towns. The cost is borne entirely by, the Central Government and the Ministry of, Environment and Forests is the nodal agency that, co-ordinates and monitors the plan. Under this, plan the major activities include treating the, pollution load from sewer systems of towns and, cities, setting up of Sewage treatment plants,, electric crematoria, low cost sanitation facilities,, , Control measures for preventing water, pollution, While the foremost necessity is prevention, setting up effluent treatment plants and treating, waste through these can reduce the pollution, load in the recipient water. The treated effluent, can be reused for either gardening or cooling, purposes wherever possible. A few years ago a, new technology called the Root Zone Process, has been developed by Thermax. This system, involves running contaminated water through, the root zones of specially designed reed beds., The reeds, which are essentially wetland plants, have the capacity to absorb oxygen from the, surrounding air through their stomatal openings., The oxygen is pushed through the porous stem, of the reeds into the hollow roots where it enters the root zone and creates conditions suitable for the growth of numerous bacteria and, fungi. These micro-organisms oxidize impurities, in the wastewaters, so that the water which finally comes out is clean., , Water Pollution, , Environmental Studies for Undergraduate Courses, , 130, , Chapter5.p65, , riverfront development, afforestation and solid, waste management., , 130, , 4/9/2004, 5:09 PM
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5.2.3 Soil Pollution, Introduction: We can no more manufacture a, soil with a tank of chemicals than we can invent, a rain forest or produce a single bird. We may, enhance the soil by helping its processes along,, but we can never recreate what we destroy. The, soil is a resource for which there is no substitute. (Environmental historian Donald Worster, reminds us that fertilizers are not a substitute, for fertile soil)., Soil is a thin covering over the land consisting of, a mixture of minerals, organic material, living, organisms, air and water that together support, the growth of plant life. Several factors contribute to the formation of soil from the parent, material. This includes mechanical weathering, of rocks due to temperature changes and abrasion, wind, moving water, glaciers, chemical, weathering activities and lichens. Climate and, time are also important in the development of, soils. Extremely dry or cold climates develop soils, very slowly while humid and warm climates develop them more rapidly. Under ideal climatic, conditions soft parent material may develop into, a centimeter of soil within 15 years. Under poor, climatic conditions a hard parent material may, require hundreds of years to develop into soil., Mature soils are arranged in a series of zones, called soil horizons. Each horizon has a distinct, texture and composition that varies with different types of soils. A cross sectional view of the, horizons in a soil is called a soil profile., The top layer or the surface litter layer called, the O horizon consists mostly of freshly fallen, and partially decomposed leaves, twigs, animal, waste, fungi and other organic materials. Normally it is brown or black., The uppermost layer of the soil called the A, horizon consists of partially decomposed organic, matter (humus) and some inorganic mineral, particles. It is usually darker and looser than the, , deeper layers. The roots of most plants are found, in these two upper layers. As long as these layers are anchored by vegetation soil stores water and releases it in a trickle throughout the, year instead of in a force like a flood. These two, top layers also contain a large amount of bacteria, fungi, earthworms and other small insects, that form complex food webs in the soil that, help recycle soil nutrients and contribute to soil, fertility., The B horizon often called the subsoil contains, less organic material and fewer organisms than, the A horizon. The area below the subsoil is, called the C horizon and consists of weathered, parent material. This parent material does not, contain any organic materials. The chemical, composition of the C-horizon helps to determine, the pH of the soil and also influences the soil’s, rate of water absorption and retention., Soils vary in their content of clay (very fine particles), silt (fine particles), sand (medium size, particles) and gravel (coarse to very coarse particles). The relative amounts of the different sizes, and types of mineral particles determine soil, texture. Soils with approximately equal mixtures, of clay, sand, silt and humus are called loams., , Causes of soil degradation, Erosion, Soil erosion can be defined as the movement of, surface litter and topsoil from one place to another. While erosion is a natural process often, caused by wind and flowing water it is greatly, accelerated by human activities such as farming, construction, overgrazing by livestock, burning of grass cover and deforestation., Loss of the topsoil makes a soil less fertile and, reduces its water holding capacity. The topsoil,, which is washed away, also contributes to water pollution clogging lakes, increasing turbidity, of the water and also leads to loss of aquatic, , Pollution, , Chapter5.p65, , 131, , 131, , 4/9/2004, 5:09 PM
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life. For one inch of topsoil to be formed it normally requires 200-1000 years depending upon, the climate and soil type. Thus if the topsoil, erodes faster than it is formed the soil becomes, a non-renewable resource., Thus it is essential that proper soil conservation, measures are used to minimize the loss of top, soil. There are several techniques that can protect soil from erosion. Today both water and, soil are conserved through integrated treatment, methods. Some of the most commonly employed methods include the two types of treatment that are generally used., •, , Area treatment which involves treating the, land, , •, , Drainage line treatment which involves, treating the natural water courses (nalas), , Continuous contour trenches can be used to, enhance infiltration of water reduce the runoff and check soil erosion. These are actually, shallow trenches dug across the slope of the, land and along the contour lines basically for, , the purpose of soil and water conservation. They, are most effective on gentle slopes and in areas, of low to medium rainfall. These bunds are stabilized by fast growing tree species and grasses., In areas of steep slopes where the bunds are, not possible, continuous contour benches (CCBs), made of stones are used for the same purpose., Gradonies can also be used to convert wastelands into agricultural lands. In this narrow, trenches with bunds on the downstream side, are built along contours in the upper reaches of, the catchment to collect run-off and to conserve, moisture from the trees or tree crops. The area, between the two bunds is use for cultivation of, crops after development of fertile soil cover., Some of the ways in which this can be achieved, are:, Live check dams which barriers created by, planting grass, shrubs and trees across the gullies can be used for this purpose., A bund constructed out of stones across the, stream can also be used for conserving soil and, water., , Area Treatment, Purpose, , Treatment Measure, , Effect, , Reduces the impact of, rain drops on the soil, , Develop vegetative cover on the, non arable land, , Minimum disturbance and, displacement of soil particles, , Infiltration of water, where it falls, , Apply water infiltration measures on, the area, , In situ soil and moisture conservation, , Minimum surface run off, , Store surplus rain water by constructing, bunds, ponds in the area, , Increased soil moisture in the area,, facilitate ground water recharge, , Ridge to valley sequencing Treat the upper catchment first and then Economically viable, less risk, proceed towards the outlet, of damage and longer life of, structures of the lower catchments, , Environmental Studies for Undergraduate Courses, , 132, , Chapter5.p65, , 132, , 4/9/2004, 5:09 PM
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Drainage line treatment, Purpose, , Treatment measure, , Effect, , Stop further deepening, of gullies and retain, sediment run-off, , Plug the gullies at formation, , Stops erosion, recharges, groundwater at the, upper level., , Reduce run-off velocity,, pass cleaner water to the, downstream side, , Crate temporary barriers in nalas, , Delayed flow and, increased groundwater, recharge, , Minimum sedimentation, in the storage basins, , Use various methods to treat the catchments, , Low construction cost, , Use local material and skills for constructing, the structures, , An Earthen checkbund is constructed out of, local soil across the stream to check soil erosion, and flow of water., A Gabion structure is a bund constructed of, stone and wrapped in galvanized chainlink., A Gabion structure with ferrocement impervious barrier has a one inch thick impervious, wall of ferrocement at the center of the structure which goes below the ground level upto, the hard strata. This ferrocement partition supported by the gabion portion is able to retain, the water and withstand the force of the runoff, water., An Underground bandhara is an underground structure across a nalla bed to function as a barrier to check the ground water, movement., Excess use of fertilizers: Approximately 25, percent of the world’s crop yield is estimated to, be directly attributed to the use of chemical fertilizers. The use of chemical fertilizes has increased significantly over the last few decades, , Structures are locally, maintained, , and is expected to rise even higher. Fertilizers, are very valuable as they replace the soil nutrients used up by plants. The three primary soil, nutrients often in short supply are potassium,, phosphorus and nitrogen compounds. These are, commonly referred to as macronutrients. Certain other elements like boron, zinc and manganese are necessary in extremely small amounts, and are known as micronutrients. When crops, are harvested a large amount of macronutrients, and a small amount of micronutrients are removed with the crops. If the same crop is grown, again depleted levels of thee nutrients can result in decreased yields. These necessary nutrients can be returned to the soil through the, application of fertilizers. In addition to fertilizers, a large amount of pesticides (chemicals used to, kill or control populations of unwanted fungi,, animals or plants often called pests) are also used, to ensure a good yield. Pesticides can be subdivided into several categories based on the kinds, of organisms they are used to control. Insecticides are used to control insect populations while, fungicides are used to control unwanted fungal, growth. Mice and rats are killed by rodenticides, while plant pests are controlled by herbicides., , Pollution, , Chapter5.p65, , 133, , 133, , 4/9/2004, 5:09 PM
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Problems with pesticide use, Pesticides not only kill the pests but also a large, variety of living things including humans. They, may be persistent or non-persistent. Persistent, pesticides once applied are effective for a long, time. However as they do not break down easily they tend to accumulate in the soil and in the, bodies of animals in the food chain., For example, DDT which was one of the first, synthetic organic insecticide to be used was, thought to be the perfect insecticide. During the, first ten years of its use (1942-1952) DDT is estimated to have saved about five million lives, primarily because of its use to control disease, carrying mosquitoes. However after a period of, use many mosquitoes and insects became tolerant of DDT, thus making it lose its effectiveness. DDT in temperate regions of the world, has a half life (the amount of time required for, half of the chemical to decompose) of 10 to 15, years. This means that if 100 kilograms of DDT, were to be sprayed over an area, 50 kilograms, would still be present in the area 10 to 15 years, later. The half-life of DDT varies according to, the soil type, temperature, kind of soil organisms present and other factors. In tropical parts, of the world the half life may be as short as six, months. The use of DDT has been banned in, some countries. India still however permits the, use of DDT though for purposes of mosquito, control only. Persistent pesticides become attached to small soil particles which are easily, moved by wind and water to different parts thus, affecting soils elsewhere. Persistent pesticides, may also accumulate in the bodies of animals,, and over a period of time increase in concentration if the animal is unable to flush them out, of its system thus leading to the phenomenon, called bioaccumulation. When an affected animal is eaten by another carnivore these pesticides are further concentrated in the body of, the carnivore. This phenomenon of acquiring, increasing levels of a substance in the bodies of, higher trophic level organisms is known as, biomagnification. This process especially in the, , Other problems associated with insecticides is, the ability of insect populations to become resistant to them thus rendering them useless in a, couple of generations. Most pesticides kill beneficial as well as pest species. They kill the predator as well as the parasitic insects that control, the pests. Thus the pest species increase rapidly, following the use of a pesticide as there are no, natural checks to their population growth. The, short term and the long-term health effects to, the persons using the pesticide and the public, that consumes the food grown by using the, pesticides are also major concerns. Exposure to, small quantities of pesticides over several years, can cause mutations, produce cancers, etc., Thus the question that comes to mind is that if, pesticides have so many drawbacks then why, are they used so extensively and what are the, substitutes for them? There are three main reasons for the use of pesticides. Firstly the use of, pesticides in the short term has increased the, amount of food that can be grown in many parts, of the world as the damage by pests is decreased. The second reason for its extensive use, is base on an economic consideration. The increased yields more than compensates the, farmer for cost of pesticides. Thirdly current, health problems especially in developing countries due to mosquitoes are impossible to control without insecticides., However more and more farmers are increasingly opting to replace chemical fertilizers and, use different methods of controlling pests without affecting their yield. Thus several different, approaches that have slightly varying and overlapping goals have been developed. Alternative, agriculture is the broadest term that is used that, includes all non-traditional agricultural methods, Environmental Studies for Undergraduate Courses, , 134, , Chapter5.p65, , case of insecticides like DDT have been proved, to be disastrous. DDT is a well known case of, biomagnification in ecosystems. DDT interferes, with the production of normal eggshells in birds, making them fragile., , 134, , 4/9/2004, 5:09 PM
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and encompasses sustainable agriculture, organic agriculture, alternative uses of traditional, crops, alternative methods for raising crops, etc., Sustainable agriculture advocates the use of, methods to produce adequate safe food in an, economically viable manner while maintaining, the state of the ecosystem. Organic agriculture, advocates avoiding the use of chemical fertilizers and pesticides. A wide variety of techniques, can be used to reduce this negative impact of, agriculture. Leaving crop residue on the soil and, incorporating it into the soil reduces erosion and, increase soil organic matter. Introduction of organic matter into the soil also makes compaction less likely. Crop rotation is an effective way, to enhance soil fertility, reduce erosion and control pests. There have been arguments both for, and against organic farming. Critics argue that, organic farming cannot produce the amount of, food required for today’s population and it is, economically viable only in certain conditions., However supporters for organic farming feel, that of the hidden costs of soil erosion and pollution are taken into account it is a viable approach. Besides organic farmers do not have to, spend on fertilizers and pesticides and also get, a premium price for their products thus making, it financially viable for them., Another way to reduce these impacts is through, the use of integrated pest management. This is, a technique that uses a complete understanding of all ecological aspects of a crop and the, particular pests to which it is susceptible to establish pest control strategies that uses no or, few pesticides. IPM promotes the use of, biopesticides. Biopesticides are derived from, three sources: microbial, botanical and biochemical. Microbial pesticides are micro-organisms such as bacteria, fungus, virus or protozoa, that fight pests through a variety of ways. They, produce toxins specific to the pests and produce, diseases in them. Biochemical pesticides contain, several chemicals that affect the reproductive, and digestive mechanisms of the pests. The most, , commonly used biopesticides are Bacillus, thuringiensis (Bt), neem (Azadirachta indica) and, trichogramma. Although they are available in, the market they are yet to become market, favourites., , Excess salts and water, Irrigated lands can produce crop yields much, higher than those that only use rainwater. However this has its own set of ill effects. Irrigation, water contains dissolved salts and in dry climates, much of the water in the saline solution evaporates leaving its salts such as sodium chloride in, the topsoil. The accumulation of these salts is, called salinization, which can stunt plant growth,, lower yields and eventually kill the crop and render the land useless for agriculture. These salts, can be flushed out of the soil by using more, water. This practice however increases the cost, of crop production and also wastes enormous, amounts of water. Flushing salts can also make, the downstream irrigation water saltier., Another problem with irrigation is water logging. This occurs when large amounts of water, is used to leach the salts deeper into the soil., However if the drainage is poor this water accumulates underground gradually raising the, water table. The roots of the plants then get, enveloped in this saline water and eventually, die., Thus in the long run it is better for us to adopt, sustainable farming practices so as to prevent, the degradation of soil., , 5.2.4 Marine Pollution, Marine pollution can be defined as the introduction of substances to the marine environment directly or indirectly by man resulting in, adverse effects such as hazards to human health,, obstruction of marine activities and lowering the, quality of sea water. While the causes of ma-, , Pollution, , Chapter5.p65, , 135, , 135, , 4/9/2004, 5:09 PM
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rine pollution may be similar to that of general, water pollution there are some very specific, causes that pollute marine waters., •, , The most obvious inputs of waste is through, pipes directly discharging wastes into the, sea. Very often municipal waste and sewage from residences and hotels in coastal, towns are directly discharged into the sea., , •, , Pesticides and fertilizers from agriculture, which are washed off the land by rain, enter water courses and eventually reach the, sea., , •, , Ships carry many toxic substances such as, oil, liquefied natural gas, pesticides, industrial chemicals, etc. in huge quantities sometimes to the capacity of 350,000 tonnes., Ship accidents and accidental spillages at, sea therefore can be very damaging to the, marine environment. Shipping channels in, estuaries and at the entrances to ports often require frequent dredging to keep them, open. This dredged material that may contain heavy metals and other contaminants, are often dumped out to sea., , •, , Offshore oil exploration and extraction also, pollute the seawater to a large extent., , Petroleum and oils washed off from the, roads normally enter the sewage system but, stormwater overflows carry these materials, into rivers and eventually into the seas., Environmental Studies for Undergraduate Courses, , 136, , Chapter5.p65, , •, , 136, , 4/9/2004, 5:09 PM
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Pollution due to organic wastes, The amount of oxygen dissolved in the water is, vital for the plants and animals living in it., Wastes, which directly or indirectly affect the, oxygen concentration, play an important role in, determining the quality of the water. Normally, the greatest volume of waste discharged to, watercourses, estuaries and the sea is sewage,, which is primarily organic in nature and is degraded by bacterial activity. Using the oxygen, present in the water these wastes are broken, down into stable inorganic compounds. However as a result of this bacterial activity the oxygen concentration in the water is reduced. When, the oxygen concentration falls below 1.5 mg/, lit, the rate of aerobic oxidation is reduced and, their place is taken over by the anaerobic bacteria that can oxidize the organic molecules without the use of oxygen. This results in end, products such as hydrogen sulphide, ammonia, and methane, which are toxic to many organisms. This process results in the formation of an, anoxic zone which is low in its oxygen content, from which most life disappears except for, anaerobic bacteria, fungi, yeasts and some protozoa. This makes the water foul smelling., Control measures: One way of reducing the, pollution load on marine waters is through the, introduction of sewage treatment plants. This, will reduce the biological oxygen demand (BOD), of the final product before it is discharged to, the receiving waters., Various stages of treatment such as primary,, secondary or advanced can be used depending, on the quality of the effluent that is required to, be treated., Primary treatment: These treatment plants use, physical processes such as screening and sedimentation to remove pollutants that will settle,, float or, that are too large to pass through simple, screening devices. This includes, stones, sticks,, rags, and all such material that can clog pipes., A screen consists of parallel bars spaced 2 to, 7cms apart followed by a wire mesh with smaller, , openings. One way of avoiding the problem of, disposal of materials collected on the screens is, to use a device called a comminuter which grinds, the coarse material into small pieces that can, then be left in the waste water. After screening, the wastewater passes into a grit chamber. The, detention time is chosen to be long enough to, allow lighter, organic material to settle. From, the grit chamber the sewage passes into a primary settling tank (also called as sedimentation, tank) where the flow speed is reduced sufficiently to allow most of the suspended solids to, settle out by gravity. If the waste is to undergo, only primary treatment it is then chlorinated to, destroy bacteria and control odours after which, the effluent is released. Primary treatment normally removes about 35 percent of the BOD and, 60 percent of the suspended solids., Secondary treatment: The main objective of, secondary treatment is to remove most of the, BOD. There are three commonly used approaches: trickling filters, activated sludge process and oxidation ponds. Secondary treatment, can remove at least 85 percent of the BOD., A trickling filter consists of a rotating distribution arm that sprays liquid wastewater over a, circular bed of ‘fist size’ rocks or other coarse, materials. The spaces between the rocks allow, air to circulate easily so that aerobic conditions, can be maintained. The individual rocks in the, bed are covered with a layer of slime, which, consists of bacteria, fungi, algae, etc. which, degrade the waste trickling through the bed., This slime periodically slides off individual rocks, and is collected at the bottom of the filter along, with the treated wastewater and is then passed, on to the secondary settling tank where it is removed., In the activated sludge process the sewage is, pumped into a large tank and mixed for several, hours with bacteria rich sludge and air bubbles, to facilitate degradation by micro-organisms., The water then goes into a sedimentation tank, , Pollution, , Chapter5.p65, , 137, , 137, , 4/9/2004, 5:09 PM
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where most of the microorganisms settle out as, sludge. This sludge is then broken down in an, anaerobic digester where methane-forming, bacteria slowly convert the organic matter into, carbon dioxide, methane and other stable end, products. The gas produced in the digester is, 60 percent methane, which is a valuable fuel, and can be put to many uses within the treatment plant itself. The digested sludge, which is, still liquid, is normally pumped out onto sludge, drying beds where evaporation and seepage, remove the water. This dried sludge is potentially a good source of manure. Activated sludge, tanks use less land area than trickling filters with, equivalent performance. They are also less expensive to construct than trickling filters and, have fewer problems with flies and odour and, can also achieve higher rates of BOD removal., Thus although the operating costs are a little, higher due to the expenses incurred on energy, for running pumps and blowers they are preferred over trickling filters., , Oxidation ponds are large shallow ponds approximately 1 to 2 metres deep where raw or, partially treated sewage is decomposed by microorganisms. They are easy to build and manage and accommodate large fluctuations in flow, and can provide treatment at a much lower cost., They however require a large amount of land, and hence can be used where land is not a limitation., Advanced sewage treatment: This involves a, series of chemical and physical process that removes specific pollutants left in the water after, primary and secondary treatment. Sewage treatment plant effluents contain nitrates and phosphates in large amounts. These contribute to, eutrophication. Thus advanced treatment plants, are designed to specifically remove these contaminants. Advanced treatment plants are very, expensive to build and operate and hence are, rarely used., , Tanker operations, Half the world production of crude oil which is, close to three billion tones a year is transported, by sea. After a tanker has unloaded its cargo of, oil it has to take on seawater as ballast for the, return journey. This ballast water is stored in the, cargo compartments that previously contained, the oil. During the unloading of the cargo a certain amount of oil remains clinging to the walls, of the container and this may amount to 800, tonnes in a 200,000 tonne tanker. The ballast, water thus becomes contaminated with this oil., When a fresh cargo of oil is to be loaded, these, compartments are cleaned with water, which, discharges the dirty ballast along with the oil, into the sea. Two techniques have substantially, reduced this oil pollution. In the load-on-top, system, the compartments are cleaned by high, pressure jets of water. The oily water is retained, in the compartment until the oil floats to the, top. The water underneath that contains only a, little oil is then discharged into the sea and the, oil is transferred to a slop tank. At the loading, terminal, fresh oil is loaded on top of the oil in, the tank and hence the name of the technique., In the second method called ‘crude oil washing’, the clingage is removed by jets of crude oil, while the cargo is being unloaded. Some modern tankers have segregated ballast where the, ballast water does not come in contact with the, oil. Thus with the introduction of these new, methods of deballasting, the amount of oil entering the sea has been considerably reduced., , Dry docking, All ships need periodic dry docking for servicing, repairs, cleaning the hull, etc. During this, period when the cargo compartments are to, Environmental Studies for Undergraduate Courses, , 138, , Chapter5.p65, , Pollution due to oil: Oil pollution of the sea, normally attracts the greatest attention because, of its visibility. There are several sources though, which the oil can reach the sea., , 138, , 4/9/2004, 5:09 PM
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completely emptied, residual oil finds its way into, the sea., , Bilge and fuel oils, As ballast tanks take up valuable space, additional ballast is sometimes carried in empty fuel, tanks. While being pumped overboard it carries, oil into the sea. Individually the quantity of oil, released may be small but it becomes a considerable amount when all the shipping operations, are taken into consideration., , Tanker accidents, A large number of oil tanker accidents happen, every year. Sometimes this can result in major, disasters such as that of the Exxon Valdez described in the section on water pollution., , Offshore oil production, Oil that is extracted from the seabed contains, some water. Even after it is passed through oil, separators the water that is discharged contains, some oil, which adds to marine pollution. Drilling muds which are pumped down oil wells, when it is being drilled normally contain 70 to, 80 percent of oil. They are dumped on the seabed beneath the platform thus heavily contaminating the water. Uncontrolled release of oil, from the wells can be catastrophic events resulting in oil pollution., Control measures for oil pollution: Cleaning, oil from surface waters and contaminated, beaches is a time consuming labour intensive, process. The natural process of emulsification, of oil in the water can be accelerated through, the use of chemical dispersants which can be, sprayed on the oil. A variety of slick-lickers in, which a continuous belt of absorbent material, dips through the oil slick and is passed through, rollers to extract the oil have been designed., Rocks, harbour walls can be cleaned with high-, , pressure steam or dispersants after which the, surface must be hosed down., Effects of marine pollution: Apart from causing eutrophication a large amount of organic, wastes can also result in the development of, red tides. These are phytoplankton blooms of, such intensity that the area is discolored. Many, important commercially important marine species are also killed due to clogging of gills or, other structures., When liquid oil is spilled on the sea it spreads, over the surface of the water to form a thin film, called an oil slick. The rate of spreading and the, thickness of the film depends on the sea temperature and the nature of the oil., Oil slicks damage marine life to a large extent., Salt marshes, mangrove swamps are likely to, trap oil and the plants, which form the basis for, these ecosystems thus suffer. For salt marsh, plants, oil slicks can affect the flowering, fruiting and germination., If liquid oil contaminates a bird’s plumage its, water repellent properties are lost. Water thus, penetrates the plumage and displaces the air, trapped between the feathers and the skin. This, air layer is necessary as it provides buoyancy and, thermal insulation. With this loss the plumage, becomes water logged and the birds may sink, and drown. Even if this does not happen loss of, thermal insulation results in exhaustion of food, reserves in an attempt to maintain body temperature often followed by death. Birds often, clean their plumage by preening and in the process consume oil which depending on its toxicity can lead to intestinal, renal or liver failure., Drill cuttings dumped on the seabed create anoxic conditions and result in the production of, toxic sulphides in the bottom sediment thus, eliminating the benthic fauna., , Pollution, , Chapter5.p65, , 139, , 139, , 4/9/2004, 5:09 PM
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Fish and shellfish production facilities can also, be affected by oil slicks. The most important, commercial damage can however also come, from tainting which imparts an unpleasant, flavour to fish and seafood and is detectable at, extremely low levels of contamination. This reduces the market value of seafood., , 5.2.5 Noise Pollution, Noise may not seem as harmful as the contamination of air or water but it is a pollution problem that affects human health and can, contribute to a general deterioration of environmental quality., Noise is undesirable and unwanted sound. Not, all sound is noise. What may be considered as, music to one person may be noise to another. It, is not a substance that can accumulate in the, environment like most other pollutants. Sound, is measured in a unit called the ‘Decibel’., , The differences between sound and noise is often subjective and a matter of personal opinion. There are however some very harmful, effects caused by exposure to high sound levels. These effects can range in severity from, being extremely annoying to being extremely, painful and hazardous., , Decibel levels of common sounds, , Effects of noise pollution on physical health, , dB, , Environmental Condition, , 0, , Threshold of hearing, , 10, , Rustle of leaves, , 20, , Broadcasting studio, , 30, , Bedroom at night, , 40, , Library, , 50, , Quiet office, , 60, , Conversational speech (at 1m), , 70, , Average radio, , 74, , Light traffic noise, , 90, , Subway train, , 100, , Symphony orchestra, , 110, , Rock band, , 120, , Aircraft takeoff, , 146, , Threshold of pain, , The most direct harmful effect of excessive noise, is physical damage to the ear and the temporary or permanent hearing loss often called a, temporary threshold shift (TTS). People suffering from this condition are unable to detect, weak sounds. However hearing ability is usually, recovered within a month of exposure. In, Maharashtra people living in close vicinity of, Ganesh mandals that play blaring music for ten, days of the Ganesh festival are usually known, to suffer from this phenomenon. Permanent, loss, usually called noise induced permanent, threshold shift (NIPTS) represents a loss of hearing ability from which there is no recovery., Below a sound level of 80 dBA haring loss does, not occur at all. However temporary effects are, noticed at sound levels between 80 and 130, dBA. About 50 percent of the people exposed, Environmental Studies for Undergraduate Courses, , 140, , Chapter5.p65, , There are several sources of noise pollution that, contribute to both indoor and outdoor noise, pollution. Noise emanating from factories, vehicles, playing of loudspeakers during various, festivals can contribute to outdoor noise pollution while loudly played radio or music systems,, and other electronic gadgets can contribute to, indoor noise pollution. A study conducted by, researchers from the New Delhi based National, Physical Laboratory show that noise generated, by firecrackers (presently available in the market) is much higher than the prescribed levels., The permitted noise level is 125 decibels, as per, the Environment (Protection) (second amendment) Rules, 1999., , 140, , 4/9/2004, 5:09 PM
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to 95 dBA sound levels at work will develop, NIPTS and most people exposed to more than, 105 dBA will experience permanent hearing loss, to some degree. A sound level of 150 dBA or, more can physically rupture the human eardrum., The degree of hearing loss depends on the duration as well as the intensity of the noise. For, example, 1hour of exposure to a 100 dBA sound, level can produce a TTS that may last for about, one day. However in factories with noisy machinery workers are subjected to high sound, levels for several hours a day. Exposure to 95, dBA for 8 hours everyday for over a period of, 10 years may cause about 15 dBA of NIPTS. In, addition to hearing losses excessive sound levels can cause harmful effects on the circulatory, system by raising blood pressure and altering, pulse rates., , Effects of noise pollution on mental health:, Noise can also cause emotional or psychological effects such as irritability, anxiety and stress., Lack of concentration and mental fatigue are, significant health effects of noise. It has been, observed that the performance of school children is poor in comprehension tasks when, schools are situated in busy areas of a city and, suffer from noise pollution., As noise interferes with normal auditory communication, it may mask auditory warning signals and hence increases the rate of accidents, especially in industries. It can also lead to lowered worker efficiency and productivity and, higher accident rates on the job., Thus noise is just more than a mere nuisance or, annoyance. It definitely affects the quality of life., It is thus important to ensure mitigation or control of noise pollution., , Permitted noise levels, Ambient Noise Levels dB, , Zone, , Day-time, , Night-time, , Silent Zone, , 50, , 40, , Residential Zone, , 55, , 45, , Commercial Zone, , 65, , 55, , Industrial Zone, , 70, , 70, , A standard safe time limit has been set for exposure to various noise levels. Beyond this ‘safe’, time continuing exposure over a period of a year, will lead to hearing loss., , Duration, , dBA, , 8 hours, , 90, , 4 hours, , 93, , 2 hours, , 96, , 1 hour, , 99, , 30 minutes, , 102, , 15 minutes, , 105, , 7 minutes, , 108, , 4 minutes, , 111, , 2 minutes, , 114, , 1 minute, , 117, , 30 seconds, , 120, , Instantaneous rupture of membrane, , 150, , Noise Control techniques, There are four fundamental ways in which noise, can be controlled: Reduce noise at the source,, block the path of noise, increase the path length, and protect the recipient. In general, the best, control method is to reduce noise levels at the, source., , Pollution, , Chapter5.p65, , 141, , 141, , 4/9/2004, 5:09 PM
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Source reduction can be done by effectively, muffling vehicles and machinery to reduce the, noise. In industries noise reduction can be done, by using rigid sealed enclosures around machinery lined with acoustic absorbing material. Isolating machines and their enclosures from the, floor using special spring mounts or absorbent, mounts and pads and using flexible couplings, for interior pipelines also contribute to reducing, noise pollution at the source., However one of the best methods of noise, source reduction is regular and thorough maintenance of operating machinery. Noise levels at, construction sites can be controlled using proper, construction planning and scheduling techniques. Locating noisy air compressors and other, equipment away from the site boundary along, with creation of temporary barriers to physically, block the noise can help contribute to reducing, noise pollution. Most of the vehicular noise, comes from movement of the vehicle tires on, the pavement and wind resistance. However, poorly maintained vehicles can add to the noise, levels. Traffic volume and speed also have significant effects on the overall sound. For example, doubling the speed increases the sound levels, by about 9 dBA and doubling the traffic volume, (number of vehicles per hour) increases sound, levels by about 3 dBA. A smooth flow of traffic, also causes less noise than does a stop-and-go, traffic pattern. Proper highway planning and, design are essential for controlling traffic noise., Establishing lower speed limits for highways that, pass through residential areas, limiting traffic, volume and providing alternative routes for truck, traffic are effective noise control measures. The, path of traffic noise can also be blocked by construction of vertical barriers alongside the highway. Planting of trees around houses can also, act as effective noise barriers. In industries different types of absorptive material can be used, to control interior noise. Highly absorptive interior finish material for walls, ceilings and floors, can decrease indoor noise levels significantly., Sound levels drop significantly with increasing, , 5.2.6 Thermal Pollution, Sources: The discharge of warm water into a, river is usually called a thermal pollution. It, occurs when an industry removes water from a, source, uses the water for cooling purposes and, then returns the heated water to its source., Power plants heat water to convert it into steam,, to drive the turbines that generate electricity., For efficient functioning of the steam turbines,, the steam is condensed into water after it leaves, the turbines. This condensation is done by taking water from a water body to absorb the heat., This heated water, which is at least 15oC higher, than the normal is discharged back into the, water body., Effects: The warmer temperature decreases the, solubility of oxygen and increases the metabolism of fish. This changes the ecological balance, of the river. Within certain limits thermal additions can promote the growth of certain fish, and the fish catch may be high in the vicinity of, a power plant. However sudden changes in temperature caused by periodic plant shutdowns, both planned and unintentional can change result in death of these fish that are acclimatized, to living in warmer waters., Tropical marine animals are generally unable to, withstand a temperature increase of 2 to 30C, Environmental Studies for Undergraduate Courses, , 142, , Chapter5.p65, , distance from the noise source. Increasing the, path length between the source and the recipient offers a passive means of control. Municipal land-use ordinances pertaining to the, location of airports make use of the attenuating effect of distance on sound levels. Use of, earplugs and earmuffs can protect individuals, effectively from excessive noise levels. Specially, designed earmuffs can reduce the sound level, reaching the eardrum by as much as 40 dBA., However very often workers tend not to wear, them on a regular basis despite company requirements for their use., , 142, , 4/9/2004, 5:09 PM
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and most sponges, mollusks and crustaceans are, eliminated at temperatures above 370C. This, results in a change in the diversity of fauna as, only those species that can live in warmer water survive., Control measures: Thermal pollution can be, controlled by passing the heated water through, a cooling pond or a cooling tower after it leaves, the condenser. The heat is dissipated into the, air and the water can then be discharged into, the river or pumped back to the plant for reuse, as cooling water. There are several ways in which, thermal pollution can be reduced. One method, is to construct a large shallow pond. Hot water, is pumped into one end of the pond and cooler, water is removed from the other end. The heat, gets dissipated from the pond into the atmosphere. A second method is to use a cooling, tower. These structures take up less land area, than the ponds. Here most of the heat transfer, occurs through evaporation. Here warm waters, coming from the condenser is sprayed downward over vertical sheets or baffles where the, water flows in thin films. Cool air enters the, tower through the water inlet that encircles the, base of the tower and rises upwards causing, evaporative cooling. A natural draft is maintained because of the density difference between the cool air outside and the warmer air, inside the tower. The waste heat is dissipated, into the atmosphere about 100 m above the, base of the tower. The cooled water is collected, at the floor of the tower and recycled back to, the power plant condensers. The disadvantage, in both these methods is however that large, amounts of water are lost by evaporation., , 5.2.7 Nuclear Hazards, Nuclear energy can be both beneficial and harmful depending on the way in which it is used., We routinely use X-rays to examine bones for, fractures, treat cancer with radiation and diagnose diseases with the help of radioactive iso-, , topes. Approximately 17 % of the electrical, energy generated in the world comes from, nuclear power plants. However on the other, hand it is impossible to forget the destruction, that nuclear bombs caused the cities of, Hiroshima and Nagasaki. The radioactive wastes, from nuclear energy have caused serious environmental damage., Nuclear fission is the splitting of the nucleus of, the atom. The resulting energy can be used for, a variety of purposes. The first controlled fission, of an atom was carried out in Germany in 1938., However the United States was the first country to develop an atomic bomb which was subsequently dropped on the Japanese cities of, Hiroshima and Nagasaki. The world’s first electricity generating reactor was constructed in the, United States in 1951 and the Soviet Union built, its first reactor in 1954. In December 1953, President Dwight D. Eisenhower in his ‘Atoms for, Peace’ speech made the following prediction:, ‘Nuclear reactors will produce electricity so, cheaply that it will not be necessary to meter it., The users will pay a fee and use as much electricity as they want. Atoms will provide a safe,, clean and dependable source of electricity.’, Today however though nuclear power is being, used as a reliable source of electricity the above, statement sounds highly optimistic. Several serious accidents have caused worldwide concern, about safety and disposal of radioactive wastes., In order to appreciate the consequences of using nuclear fuels to generate energy it is important to understand how the fuel is processed., Low-grade uranium ore, which contains 0.2, percent uranium by weight, is obtained by surface or underground mining. After it is mined, the ore goes through a milling process where it, is crushed and treated with a solvent to concentrate the uranium and produces yellow cake, a material containing 70 to 90 percent uranium, oxide. Naturally occurring uranium contains only, 0.7 percent of fissionable U-235, which is not, , Pollution, , Chapter5.p65, , 143, , 143, , 4/9/2004, 5:09 PM
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high enough for most types of reactors. Hence, it is necessary to increase the amount of U-235, by enrichment though it is a difficult and expensive process. The enrichment process increases the U-235 content from 0.7 to 3 percent., Fuel fabrication then converts the enriched material into a powder, which is then compacted, into pellets. These pellets are sealed in metal, fuel rods about 4 meters in length which is then, loaded into the reactor. As fission occurs the, concentration of U-235 atoms decreases. After, about three years, a fuel rod does not have, enough radioactive material to sustain a chain, reaction and hence the spent fuel rods must be, replaced by new ones. The spent rods are however still very radioactive containing about one, percent U-235 and one percent plutonium., These rods are a major source of radioactive, waste material produced by a nuclear reactor., Initially it was thought that spent fuel rods could, be reprocessed to not only provide new fuel but, also to reduce the amount of nuclear waste., However the cost of producing fuel rods by reprocessing was found to be greater than the, cost of producing fuel rods from ore. Presently, India does operate reprocessing plants to reprocess spent fuel as an alternative to storing them, as nuclear waste. At each step in the cycle there, is a danger of exposure and poses several health, and environmental concerns., Although nuclear power has significant benefits, an incident which changed people’s attitudes, towards nuclear power plants was the, Chernobyl disaster that occurred in 1986., Chernobyl is a small city in Ukraine near the, border with Belarus north of Kiev. At 1.00 am, April 25, 1986 a test to measure the amount of, electricity that the still spinning turbine would, produce if steam were shut off was being conducted at the Chernobyl Nuclear Power Station4. This was important information since the, emergency core cooling system required energy, for its operation and the coasting turbine could, provide some of that energy until another source, , At 1.00am, the operators shut off most of the, emergency warning signals and turned on all, the eight pumps to provide adequate cooling, for the reactor following the completion of the, test. Just as the final stages for the test were, beginning a signal indicated excessive reaction, in the reactor. In spite of the warning the operators blocked the automatic reactor shutdown, and began the test. As the test continued the, power output of the reactor rose beyond its, normal level and continued to rise. The operators activated the emergency system designed, to put the control rods back into the reactor, and stop the fission. But it was already too late., The core had already been deformed and the, rods would not fit properly thus the reaction, could not be stopped. In 4.5 seconds the energy level of the reactor increased two thousand times. The fuel rods ruptured the cooling, water turned into steam and a steam explosion, occurred. The lack of cooling water allowed the, reactor to explode. The explosion blew the 1000, metric ton concrete roof from the reactor and, the reactor caught fire. This resulted in the, world’s worst nuclear accident and it took ten, days to bring the runaway reaction under control., , Environmental Studies for Undergraduate Courses, , 144, , Chapter5.p65, , became available. The amount of steam being, produced was reduced by lowering the control, rods into the reactor. But the test was delayed, because of a demand for electricity and a new, shift of workers came on duty. The operators, failed to program the computer to maintain, power at 700 megawatts and the output, dropped to 30 megawatts. This presented an, immediate need to rapidly increase the power, and many of the control rods were withdrawn., Meanwhile an inert gas (xenon) had accumulated on the fuel rods. The gas absorbed the, neutrons and slowed the rate of power increase., In an attempt to obtain more power the operators withdrew all the control rods. This was a, second serious safety violation., , 144, , 4/9/2004, 5:09 PM
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There were of course immediate fatalities, but, the long-term consequences were devastating., 116,000 people were evacuated of which, 24,000 had received high doses of radiation., Even today many people suffer from illnesses, they feel are related to their exposure to the, fallout from Chernobyl. In 1996 ten years after, the accident it was clear that one of the longterm effects was the increased frequency of, thyroid cancer in children., The degree and the kind of damage from, nuclear accidents vary with the kind of radiation, the amount of radiation, the duration of, exposure and the types of cells irradiated. Radiation can also cause mutations which are, changes in the genetic makeup of the cells., Mutations can occur in the ovaries or the testes, leading to the formation of mutated eggs or, sperms which in turn can lead to abnormal offspring. Mutations can also occur in the tissues, of the body ad may manifest themselves as abnormal tissue growths known as cancer. Two, common cancers that are linked to increased, radiation exposure are leukemia and breast cancer., , 5.3 SOLID WASTE MANAGEEMNT:, CAUSES, EFFECTS AND CONTROL MEASURES OF URBAN AND INDUSTRIAL, WASTE, In ancient cities, food scraps and other wastes, were simply thrown into the unpaved streets, where they accumulated. Around 320 B.C. in, Athens, the first known law forbidding this practice was established and a system of waste removal began to evolve in several eastern, Mediterranean cities. Disposal methods were, very crude and often were just open pits outside the city walls. As populations increased,, efforts were made to transport the wastes out, further thus creating city dumps. Until recently, the disposal of municipal solid waste did not, attract much public attention. The favoured, , means of disposal was to dump solid wastes, outside the city or village limits., Around most towns and cities in India the approach roads are littered with multi-coloured, plastic bags and other garbage. Waste is also, burnt to reduce its volume. Modern methods, of disposal such as incineration and the development of sanitary landfills, etc. are now attempting to solve these problems. Lack of space, for dumping solid waste has become a serious, problem in several cities and towns all over the, world. Dumping and burning wastes is not an, acceptable practice today from either an environmental or a health perspective. Today disposal of solid waste should be part of an, integrated waste management plan. The, method of collection, processing, resource recovery and the final disposal should mesh with, one another to achieve a common objective., , Characteristics of municipal solid waste, Solid wastes are grouped or classified in several, different ways. These different classifications are, necessary to address the complex challenges of, solid waste management in an effective manner. The term municipal solid waste (MSW) is, generally used to describe most of the non-hazardous solid waste from a city, town or village, that requires routine collection and transport to, a processing or disposal site. Sources of MSW, include private homes, commercial establishments and institutions as well as industrial facilities. However MSW does not include wastes, from industrial processes, construction and, demolition debris, sewage sludge, mining wastes, or agricultural wastes., Municipal solid waste contains a wide variety of, materials. It can contain food waste such as vegetable and meat material, left over food, egg, shells, etc which is classified as wet garbage as, well as paper, plastic, tetrapacks, plastic cans,, newspaper, glass bottles, cardboard boxes, alu-, , Pollution, , Chapter5.p65, , 145, , 145, , 4/9/2004, 5:09 PM
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minum foil, metal items, wood pieces, etc. which, is classified as dry garbage., Control measures of urban and industrial, wastes: An integrated waste management, strategy includes three main components:, 1. Source reduction, 2. Recycling, 3. Disposal, Source reduction is one of the fundamental, ways to reduce waste. This can be done by using less material when making a product, reuse, of products on site, designing products or packaging to reduce their quantity. On an individual, level we can reduce the use of unnecessary items, while shopping, buy items with minimal packaging, avoid buying disposable items and also, avoid asking for plastic carry bags., Recycling is reusing some components of the, waste that may have some economic value., Recycling has readily visible benefits such as conservation of resources reduction in energy used, during manufacture and reducing pollution levels. Some materials such as aluminum and steel, can be recycled many times. Metal, paper, glass, and plastics are recyclable. Mining of new aluminum is expensive and hence recycled aluminum has a strong market and plays a significant, role in the aluminum industry. Paper recycling, can also help preserve forests as it takes about, 17 trees to make one ton of paper. Crushed, glass (cullet) reduces the energy required to, manufacture new glass by 50 percent. Cullet, lowers the temperature requirement of the, glassmaking process thus conserving energy and, reducing air pollution. However even if recycling, is a viable alternative, it presents several problems., The problems associated with recycling are either technical or economical. Plastics are difficult to recycle because of the different types of, polymer resins used in their production. Since, each type has its own chemical makeup differ-, , Disposal of solid waste is done most commonly, through a sanitary landfill or through incineration. A modern sanitary landfill is a depression, in an impermeable soil layer that is lined with, an impermeable membrane. The three key characteristics of a municipal sanitary landfill that, distinguish it from an open dump are:, •, , Solid waste is placed in a suitably selected, and prepared landfill site in a carefully prescribed manner., , •, , The waste material is spread out and compacted with appropriate heavy machinery., , •, , The waste is covered each day with a layer, of compacted soil., , The problem with older landfills are associated, with groundwater pollution. Pollutants seeping, out from the bottom of a sanitary landfill, (leachates) very often percolate down to the, groundwater aquifer no matter how thick the, underlying soil layer. Today it is essential to have, suitable bottom liners and leachate collection, systems along with the installation of monitoring systems to detect groundwater pollution., The organic material in the buried solid waste, Environmental Studies for Undergraduate Courses, , 146, , Chapter5.p65, , ent plastics cannot be recycled together. Thus, separation of different plastics before recycling, is necessary. Similarly in recycled paper the fibers are weakened and it is difficult to control, the colour of the recycled product. Recycled, paper is banned for use in food containers to, prevent the possibility of contamination. It very, often costs less to transport raw paper pulp than, scrap paper. Collection, sorting and transport, account for about 90 percent of the cost of, paper recycling. The processes of pulping,, deinking and screening wastepaper are generally more expensive than making paper from, virgin wood or cellulose fibers. Very often thus, recycled paper is more expensive than virgin, paper. However as technology improves the cost, will come down., , 146, , 4/9/2004, 5:09 PM
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will decompose due to the action of microorganisms. At first the waste decomposes aerobically until the oxygen that was present in the, freshly placed fill is used up by the aerobic microorganisms. The anerobes take over producing methane which is poisonous and highly, explosive when mixed with air in concentrations, between 5 and 15 percent. The movement of, gas can be controlled by providing impermeable, barriers in the landfill. A venting system to collect the blocked gas and vent it to the surface, where it can be safely diluted and dispersed into, the atmosphere is thus a necessary component, of the design of sanitary landfills., Even though landfilling is an economic alternative for solid waste disposal, it has become increasingly difficult to find suitable landfilling sites, that are within economic hauling distance and, very often citizens do not want landfills in their, vicinity. Another reason is that no matter how, well engineered the design and operation may, be, there is always the danger of some environmental damage in the form of leakage of, leachates., Incineration is the process of burning municipal solid waste in a properly designed furnace, under suitable temperature and operating conditions. Incineration is a chemical process in, which the combustible portion of the waste is, combined with oxygen forming carbon dioxide, and water, which are released into the atmosphere. This chemical reaction called oxidation, results in the release of heat. For complete oxidation the waste must be mixed with appropriate volumes of air at a temperature of about, 815o C for about one hour. Incineration can, reduce the municipal solid waste by about 90, percent in volume and 75 percent in weight., The risks of incineration however involve airquality problems and toxicity and disposal of the, fly and bottom ash produced during the incineration process. Fly ash consists of finely divided, particulate matter, including cinders, mineral, dust and soot. Most of the incinerator ash is, , bottom ash while the remainder is fly ash. The, possible presence of heavy metals in incinerator, ash can be harmful. Thus toxic products and, materials containing heavy metals (for example, batteries and plastics) should be segregated., Thus extensive air pollution control equipment, and high-level technical supervision and skilled, employees for proper operation and maintenance is required., Thus while sanitary landfills and incinerators have, their own advantages and disadvantages, the, most effective method of solid waste management is source reduction and recycling., , Vermi – Composting, Nature has perfect solutions for managing the, waste it creates, if left undisturbed. The biogeochemical cycles are designed to clear the, waste material produced by animals and plants., We can mimic the same methods that are, present in nature. All dead and dry leaves and, twigs decompose and are broken down by organisms such as worms and insects, and is finally broken down by bacteria and fungi, to form, a dark rich soil-like material called compost., These organisms in the soil use the organic material as food, which provides them with nutrients for their growth and activities. These, nutrients are returned to the soil to be used again, by trees and other plants. This process recycles, nutrients in nature., This soil can be used as a manure for farms and, gardens., , Pollution, , Chapter5.p65, , 147, , 147, , 4/9/2004, 5:09 PM
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Steps for Vermi-Compost, •, , Dig a pit about half a meter square, one, meter deep., , •, , Line it with straw or dried leaves and, grass., , •, , Organize the disposal of organic waste, into the pit as and when generated., , •, , Introduce a culture of worms that is now, produced commercially., , •, , Ensure that the contents are covered, with a sprinkling of dried leaves and soil, everyday., , •, , Water the pit once or twice a week to, keep it moist., , •, , Turn over the contents of the pit ever, 15 days., , •, , In about 45 days the waste will be decomposed by the action of the microorganisms., , •, , The soil derived is fertile and rich in nutrients., , Characteristics of hazardous wastes, A waste is classified as a hazardous waste if it, exhibits any of the four primary characteristics, based on the physical or chemical properties of, toxicity, reactivity, ignitability and corrosivity. In, addition to this waste products that are either, infectious or radioactive are also classified as, hazardous, , Toxic wastes are those substances that are poisonous even in very small or trace amounts., Some may have an acute or immediate effect, on humans or animals causing death or violent, illness. Others may have a chronic or long term, effect slowly causing irreparable harm to exposed persons. Acute toxicity is readily apparent because organisms respond to the toxin, shortly after being exposed. Chronic toxicity is, much more difficult to determine because the, effects may not be seen for years. Certain toxic, wastes are known to be carcinogenic, causing, cancer and others may be mutagenic causing, biological changes in the children of exposed, people and animals., Reactive wastes are those that have a tendency, to react vigorously with air or water, are unstable to shock or heat, generate toxic gases or, explode during routine management. For example, gunpowder, nitroglycerine, etc., , Hazardous wastes, Modern society produces large quantities of, hazardous waste which are generated by chemical manufacturing companies, petroleum refineries, paper mills, smelters and other industries., Hazardous wastes are those that can cause harm, to humans or the environment. Wastes are normally classified as hazardous waste when they, cause or significantly contribute to an increase, in mortality or an increase in serious irreversible, or incapacitating reversible illness or pose a sub-, , Ignitable wastes are those that burn at relatively, low temperatures (less than 60 C) and are capable of spontaneous combustion during storage, transport or disposal. For example, gasoline,, paint thinners, and alcohol., Corrosive wastes are those that destroy materials and living tissue by chemical reaction. For, example, acids and bases., Environmental Studies for Undergraduate Courses, , 148, , Chapter5.p65, , stantial present or potential hazard to human, health or the environment when improperly, treated, stored, transported or disposed of., , 148, , 4/9/2004, 5:09 PM
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Infectious wastes include human tissue from, surgery, used bandages and hypodermic, needles, microbiological materials, etc., , shortening their life span. Lead may also damage nerve tissue which can result in brain disease., , Radioactive waste is basically an output from, the nuclear power plants and can persist in the, environment for thousands of years before it, decays appreciably., , Mercury occurs in several different forms. Mercury is used in the production of chlorine. It is, also used as a catalyst in the production of some, plastics. Industrial processes such as the production of chlorine and plastics are responsible for, most of the environmental damage resulting, from mercury. Our body has a limited ability to, eliminate mercury. In the food web mercury, becomes more concentrated as it is taken up by, various organisms. In an aquatic environment,, mercury can be absorbed by the plankton which, are then consumed by fish. In addition, fish take, up mercury through their gills and by eating, , Environmental problems and health risks, caused by hazardous wastes., As most of the hazardous wastes are disposed, of on or in land the most serious environmental, effect is contaminated groundwater. Once, groundwater is polluted with hazardous wastes, it is very often not possible to reverse the damage., Pesticides are used increasingly to protect and, increase food production. They form residues, in the soil which are washed into streams which, then carry them forwards. The residues may, persist in the soil or in the bottom of lakes and, rivers. Exposure can occur through ingestion,, inhalation and skin contact resulting in acute or, chronic poisoning. Today we have an alternative to the excess use of pesticides through the, use of Integrated Pest Management (IPM). The, IPM system uses a wide variety of plants and, insects to create a more natural process. The, natural balance between climate, soil and insect populations can help to prevent an insect, from overpopulating an area and destroying a, particular crop., Lead, mercury and arsenic are hazardous substances which are often referred to as heavy, metals. Lead is an abundant heavy metal and is, relatively easy to obtain. It is used in batteries,, fuel, pesticides, paints, pipes and other places, where resistance to corrosion is required. Most, of the lead taken up by people and wildlife is, stored in bones. Lead can affect red blood cells, by reducing their ability to carry oxygen and, , Minamata-An important lesson about, mercury, A case of human mercury poisoning which, occurred about forty years ago in the, Minamata bay in Japan taught the world an, important lesson about the dangers of mercury poisoning. A large plastics plant located, near the Minamata bay used a mercury containing compound in a reaction to produce, vinyl chloride a common plastic material. The, left over mercury was dumped into the Bay, along with other wastes from the plant., Though the mercury was in its less toxic inorganic state when dumped microorganisms, at the bottom of the bay converted the mercury into its organic form. This organic mercury then entered into the tissues of fish, which were in turn consumed by the people, living in the area. The contaminated fish thus, caused an outbreak of poisoning killing and, affecting several people. Mothers who had, eaten the contaminated fish gave birth to, infants who showed signs of mercury poisoning. Mercury poisoning is thus called, Minamata Disease., , Pollution, , Chapter5.p65, , 149, , 149, , 4/9/2004, 5:09 PM
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other fish contaminated with mercury. Generally older the fish greater is the mercury concentration in its body. Birds that eat the fish, concentrate even more mercury in their bodies., It is a cumulative poison ( it builds up in the body, over long periods of time) and is known to cause, brain damage., Thousands of chemicals are used in industry, everyday. When used incorrectly or inappropriately they can become health hazards. PCBs, (Polychlorinated biphenyls) are resistant to fire, and do not conduct electricity very well which, makes them excellent materials for several industrial purposes. Rainwater can wash PCBs out, of disposal areas in dumps and landfills thus, contaminating water. PCBs do not break down, very rapidly in the environment and thus retain, their toxic characteristics. They cause long term, exposure problems to both humans and wildlife. PCBs are concentrated in the kidneys and, liver and thus cause damage. They cause reproductive failure in birds and mammals., Vinyl chloride is a chemical that is widely used, in the manufacture of plastic. Usually people are, only exposed to high levels of vinyl chloride if, they work with it or near it but exposure can, also occur from vinyl chloride gas leaks. After a, long continuous exposure (one to three years), in humans, vinyl chloride can cause deafness,, vision problems, circulation disorders and bone, deformities. Vinyl chloride can also cause birth, defects., It is essential to substitute the use of PCBs and, vinyl chloride with chemicals that are less toxic., Polyvinyl chloride use can be lowered by reducing our use of plastics. Thus by reducing waste,, encouraging recycling and using products that, are well made and durable we can greatly reduce our consumption of these chemicals thus, curtailing our exposure to these substances., We may not realize it but many household, chemicals can be quite toxic to humans as well, , Today the most common methods for disposing off hazardous wastes are land disposal and, incineration. In countries where there is abundant land available for disposal for example,, North America land disposal is the most widely, used method. In countries like Europe and Japan where land is not readily available and is, expensive, incineration is the preferred method, for disposal. In spite of strong laws however illegal dumping of these wastes continues. Hazardous waste management must move beyond, burying and burning. Industries need to be encouraged to generate less hazardous waste in, their manufacturing processes. Although toxic, wastes cannot be entirely eliminated, technologies are available for minimizing, recycling and, treating wastes. An informed public can also, contribute in a big way towards this end. It is, essential for us to understand the ill effects of, chemical substances so that we can make informed decisions about its use. We might decide that the benefits of the use of a toxic, substance do not outweigh the risks and choose, not to use it at all or we may decide that it is, acceptable to use a substance under certain, specific circumstances where it is adequately, controlled and exposure to toxic levels is prevented., , 5.4 ROLE OF AN INDIVIDUAL IN PREVENTION OF POLLUTION, There are a host of environmental problems, caused by human actions on the environment., If we are to respond to these problems we have, to recognize that each of us is individually responsible for the quality of the environment we, live in. Our personal actions can either worsen, or improve our environmental quality. Several, Environmental Studies for Undergraduate Courses, , 150, , Chapter5.p65, , as wildlife. Most of the dangerous substances, in our homes are found in various kinds of cleaners, solvents and products used in automotive, care. When these products are used incorrectly, they have the potential to be harmful., , 150, , 4/9/2004, 5:09 PM
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people may feel that environmental problems, can be solved with quick technological fixes., While a majority of individuals would want a, cleaner environment, not many of them want, to make major changes in their lifestyle that, could contribute to a cleaner environment. Decisions and actions taken by individuals to a very, large extent determine the quality of life for, everyone. This necessitates that individuals, should not only be aware of various environmental issues and the consequences of their, actions on the environment but should also, make a firm resolve to develop environmentally, ethical lifestyles., With the help of solar energy, natural processes, developed over billions of years can indefinitely, renew the topsoil, water, air, forests, grasslands, and wildlife on which all forms of life depend,, but only as long as we do not use these potentially renewable resources faster than they are, replenished. Some of our wastes can be diluted,, decomposed and recycled by natural processes, indefinitely as long as these processes are not, overloaded. Natural processes also provide services of flood prevention, erosion control at no, costs at all. We must therefore learn to value, these resources and use them sustainably., , •, , Try to plant trees wherever you can and, more importantly take care of them. They, reduce air pollution., , •, , Reduce the use of wood and paper products wherever possible. Manufacturing paper leads to pollution and loss of forests, which releases oxygen and takes up carbon, dioxide. Try to recycle paper products and, use recycled paper wherever possible., , •, , From the mail you receive reuse as many, envelopes that you can., , •, , Do not buy furniture, doors, window frames, made from tropical hardwoods such as teak, and mahogany. These are forest based., , •, , Help in restoring a degraded area near your, home or join in an afforestation program., , •, , Use pesticides in your home only when absolutely necessary and use them in as small, amounts as necessary. Some insect species, help to keep a check on the populations of, pest species., , •, , Advocate organic farming by asking your, grocery store to stock vegetables and fruits, grown by an organic method. This will automatically help to reduce the use of pesticides., , •, , Reduce the use of fossil fuels by either walking up a short distance using a car pool,, sharing a bike or using public transport. This, reduces air pollution., , •, , Shut off the lights and fans when not, needed., , •, , Don’t use aerosol spray products and commercial room air fresheners. They damage, the ozone layer., , Concepts that help individuals contribute towards a better quality of our environment and, human life., •, , Develop respect or reverence for all forms, of life., , •, , Each individual must try to answer four basic questions:, Where do the things that I consume, come from?, What do I know about the place where, I live?, How am I connected to the earth and, other living things?, What is my purpose and responsibility, as a human being?, , Pollution, , Chapter5.p65, , 151, , 151, , 4/9/2004, 5:09 PM
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•, , Do not pour pesticides, paints, solvents, oil, or other products containing harmful chemicals down the drain or on the ground., , •, , Start individual or community composting, or vemicomposting plants in your neighborhood and motivate people to join in., , •, , Buy consumer goods that last, keep them, as long as possible and have them repaired, as far as possible instead of disposing them, off. Such products end up in landfills that, could pollute ground water., , •, , Do not litter the roads and surroundings just, because the sweeper from the Municipal, Corporation will clean it up. Take care to, put trash into dustbins or bring it back home, with you where it can be appropriately disposed., , •, , Buy consumer goods ages in refillable glass, containers instead of cans or throwaway, bottles., , •, , You must realize that you cannot do everything and have solutions for every problem, in the world. You can however concentrate, on issues that you feel strongly about and, can do something about. Focusing your, energy on a particular issue will help you, get better results., , •, , You could join any of the several NGOs that, exist in our country or become volunteers., Organize small local community meetings, to discuss positive approaches of pollution, prevention., , •, , Learn about the biodiversity of your own, area. Understand the natural and cultural, assets. This would help you to develop a, sense of pride in your city/town/village and, will also help you understand the problems, facing their survival., , •, , Use rechargeable batteries., , •, , Try to avoid asking for plastic carry bags, when you buy groceries or vegetables or, any other items. Use your own cloth bag, instead., , •, , Use sponges and washable cloth napkins,, dish towels and handkerchiefs instead of, paper ones., , •, , Don’t use throwaway paper and plastic, plates and cups when reusable versions are, available., , •, , Recycle all newspaper, glass, aluminum and, other items accepted for recycling in your, area. You might have to take a little trouble, to locate such dealers., , •, , Set up a compost bin in your garden or terrace and use it to produce manure for your, plants to reduce use of fertilizers., , You cannot improve your world by not voting. You have the option to make a choice, rather than complain later on., , •, , It is important that you do not get discouraged at the first sign of trouble. Do not dwell, on the negative aspects. But take positive, actions wherever you can to make the world, a better place to live in., , •, , When talking to elected officials always be, courteous and reasonable. You may disagree with a particular position but be re-, , •, , •, , Try to lobby and push for setting up garbage separation and recycling programs in, your localities., , •, , Choose items that have the least packaging or no packaging., , Environmental Studies for Undergraduate Courses, , 152, , Chapter5.p65, , 152, , 4/9/2004, 5:09 PM
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spectful in doing so as you will gain little by, being hostile and brash., •, , Take care to put into practice what you, preach. Remember environment protection, begins with YOU., , 5.5 POLLUTION CASE STUDIES, A case study of groundwater pollution in, India, An example of groundwater pollution caused, by excessive extraction is that fluoride contamination. Fluorisis is not a localized problem. It has, spread across 19 states and across a variety of, ecological regions ranging from the Thar desert,, the Gangetic plains and the Deccan plateau., Each of these regions are distinct in terms of, rainfall, soil type, groundwater recharge regime,, climatic conditions and hydrology. High fluoride, concentration in groundwater is a natural phenomenon in several countries such as China, Sri, Lanka, West Indies, Spain, Holland, Italy and, Mexico. Experts claim that a fluoride belt, stretches across the Middle East across Pakistan, and India and then into Southeast Asia and the, South of China. According to a report of the, Rajiv Gandhi National Drinking Water mission,, the bedrock of the Indian peninsula consists of, a number of fluoride bearing minerals. When, the bedrock weathers the fluoride leaches into, water and the soil. Although the Indian peninsular bedrock has always been the same, this, problem has only surfaced during the last three, decades. This is related to the over extraction of, groundwater which has resulted in the tapping, of aquifers with high fluoride concentrations., The beginnings of this phenomenon can be, traced back to the 1970s and the 1980s when, there was massive state investment in rural, water development for irrigation as well as for, drinking. Encouraged by state subsidies on diesel and electricity, people invested in diesel and, , submersible pumps in a bid to extract groundwater through borewells. This policy aggravated, the fluoride problem., Fluoride mainly enters the human body through, drinking water where 96 to 99 percent of it, combines with the bones as it has an affinity for, calcium phosphate in the bones. Excess intake, of fluoride can lead to dental fluorosis, skeletal, fluorosis or non-skeletal fluorosis. Dental fluorosis is characterized by discoloured, blackened,, mottled or chalky white teeth. Skeletal fluorosis, leads to severe and permanent bone and joint, deformities. Non-skeletal fluorosis leads to, gastro-intestinal problems and neurological disorders. Fluoride can damage the foetus and, adversely affect the IQ of children., Once fluoride is detected in water, the only solution is to deflouridate it. Various technologies, are available for this process. However the type, of technology to be selected depends upon the, fluoride levels in the water and the volume of, water to be deflouridated. None of the Indian, technologies are however fool-proof., Deflouridation plants and household water treatment kits are stop-gap solutions., , A case study of pesticide pollution in India, One of the most terrifying effects of pesticide, contamination of ground water came to light, when pesticide residues were found in bottled, water. Between July and December 2002, the, Pollution Monitoring Laboratory of the New, Delhi based Center for Science and Environment, (CSE) analysed 17 brands of bottled water both, packaged drinking water and packaged natural, mineral water commonly sold in areas that fall, within the national capital region of Delhi. Pesticide residues of organochlorine and organophosphorus pesticides which are most, commonly used in India were found in all the, samples. Among organochlorines, gammahexachlorocyclohexane (lindane) and DDT were, , Pollution, , Chapter5.p65, , 153, , 153, , 4/9/2004, 5:09 PM
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prevalent while among organophosphorus pesticides, Malathion and Chlorpyrifos were most, common. All these were present above permissible limits specified by the European Economic, Community, which is the norm, used all over, Europe., One may wonder as to how these pesticide residues get into bottled water that is manufactured by several big companies. This can be, traced to several facts. There is no regulation, that the bottled water industry must be located, in ‘clean’ zones. Currently the manufacturing, plants of most brands are situated in the dirtiest, industrial estates or in the midst of agricultural, fields. Most companies use bore wells to pump, out water from the ground from depths varying from 24m to even 152 m below the ground., The raw water samples collected from the plants, also reveled the presence of pesticide residues., This clearly indicated that the source of pesticide residues in the polluted groundwater are, used to manufacture the bottled water. This is, despite the fact that all bottled water plants use, a range of purification methods. Thus obviously, the fault lies in the treatment methods used., These plants use the membrane technology, where the water is filtered using membranes, with ultra-small pores to remove fine suspended, solids and all bacteria and protozoa and even, viruses. While nanofiltration can remove insecticides and herbicides it is expensive and thus, rarely used. Most industries also use an activated, charcoal adsorption process, which is effective, in removing organic pesticides but not heavy, metals. To remove pesticides the plants use reverse osmosis and granular activated charcoal, methods. Thus even though manufacturers, claim to use these process the presence of pesticide residues points to the fact that either, manufacturers do not use the treatment process effectively or only treat a part of the raw, water., , Similarly six months after CSE reported pesticide residues in bottled water it also found these, pesticides in popular cold drink brands sold, across the country. This is because the main ingredient in a cold drink or a carbonated nonalcoholic beverage is water and there are no, standards specified for water to be used in these, beverages in India., There were no standards for bottled water in, India till on September 29, 2000 the Union Ministry of Health and Family Welfare issued a notification (no759(E)) amending the Prevention of, Food Adulteration Rules, 1954. The BIS (Bureau, of Indian Standards) certification mark became, mandatory for bottled water from March 29,, 2001. However the parameters for pesticide, residues remained ambiguous. Following the, report published by CSE in Down to Earth, Vol, 11, no. 18, a series of Committees were established and eventually on 18th July 2003 amendments were made in the Prevention of Food, Adulteration Rules stating that pesticide residues, considered individually should not exceed, 0.0001mg.lit and the total pesticide residues will, not be more than 0.0005 mg/lit that the analysis shall be conducted by using internationally, established test methods meeting the residue, limits specified herein. This notification came into, force from January 1, 2004., , A case study of river pollution in India, Almost all the rivers in India are polluted. The, causes of pollution may also be more or less similar. This is a case study of the river Damodar as, reported in Down to Earth. The 563 km long, Environmental Studies for Undergraduate Courses, , 154, , Chapter5.p65, , The low concentration of pesticide residues in, bottled water do not cause acute or immediate, effect. However repeated exposure even to extremely miniscule amounts can result in chronic, effects like cancer, liver and kidney damage,, disorders of the nervous system, damage to the, immune system and birth defects., , 154, , 4/9/2004, 5:09 PM
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Damodar river originates near Chandwa village, in the Chhotanagpur hills in Bihar’s Palamau, district. It flows through one of the richest mineral belts in the world before draining into the, Hooghly, about 50 km south of Calcutta. Indian industry depends heavily on this region as, 60 percent of the coal consumed in our country, comes from the Chhotanagpur belt. Coal based, industries of all types dot the area because of, locational advantages and the easy availability, of water and power. In addition various industries such as the steel, cement, fertilizer and, explosive plants are also located here. The river, Damodar is polluted with minerals, mine rejects, and toxic effluents. Both its water and its sand, are infested by coal dust and waste from these, industries. There are seven thermal power plants, in the Damodar valley. The states of Bihar and, West Bengal depend almost entirely on this area, for their power requirements. These power, plants not only consume a lot of water but also, dump ash in the valley., , Mining, As underground mines cannot keep pace with, the rising demand, 60 percent of the coal extracted from the area comes from open cast, mines which are responsible for serious land, degradation. The disposal of rock and soil extracted along with the coal only adds to the, problem., , Industries, The industries in the area do not have proper, effluent treatment plants. Among the big coal, based industries the washeries account for the, bulk of the pollution in terms of the total suspended solids (TSS), oil and grease. About 20, percent of the coal handled goes out in the form, of slurry which is deposited in the ponds outside. After the slurry settles, coalfine (the sediment) is collected manually. Due to inadequate, retrieval methods very often the water discharges into the river from the pond carries high, , amounts of fine coal particles and oil thus polluting the river. The other major coal based polluters are the coke oven plants that heat coal to, temperatures as high as 1100oC in the absence, of oxygen to prepare it for use in blast furnaces, and foundries. The volatile components in the, coal are removed, leaving hot, non-volatile coke, in the oven which is washed with huge quantities of water. This water that contains oil and, suspended particles is then discharged into the, river., , Flyash from the thermal power plants, Only one of the thermal power plants has an, electrostatic precipitator to collect the fly ash, while the other just make do with mechanical, dust collectors. As most of these plants are located on the banks of the river the fly ash eventually finds its way into the river. The bottom, ash from the boilers is mixed with water to form, a slurry which is then drained into ash ponds., Most of the ponds are full and in several cases, the drainage pipes are choked. The slurry is, therefore directly discharged into the river., , Effects, The river and its tributaries are the largest source, of drinking water for the huge population that, lives in the valley. On April 2, 1990 about, 200,000 litres of furnace oil spilled into the river, from the Bokaro Steel Plant. This oil traveled, 150 km downstream to Durgapur. For a week, after the incident five million people drank contaminated water in which the oil levels were 40, to 80 times higher than the permissible value of, 0.03 mg/l., The Damodar Action Plan an end-of-the pipe, pollution treatment scheme seeks to tackle effluents. One viable option could be to switch to, less polluting industries and cleaner technology., This would need strong Government initiative, and also a mass movement by people., , Pollution, , Chapter5.p65, , 155, , 155, , 4/9/2004, 5:09 PM
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5.6 DISASTER MANAGEMENT: FLOODS,, EARTHQUAKES, CYCLONES, LANDSLIDES, The Indian subcontinent is very vulnerable to, droughts, floods, cyclones, earthquakes, landslides, avalanches and forest fires. Among the, 36 states and Union territories in the country,, 22 are prone to disasters., Among all the disasters that occur in the country, floods are the most frequently occurring, natural disasters, due to the irregularities of the, Indian monsoon. About 75 percent of the annual rainfall in India is concentrated in three to, four months of the monsoon season. As a result there is a very heavy discharge from the, rivers during this period causing widespread, floods. Approximately 40 million hectares of land, in the country has been identified as being prone, to floods. Major floods are mainly caused in the, Ganga-Brahmaputra-Meghna basin which carries 60 percent of the total river flow of our country., , From management to mitigation of disasters, , India has a long coastline of 5700 kms, which is, exposed to tropical cyclones arising in the Bay, of Bengal and the Arabian sea. The Indian Ocean, is one of the six major cyclone prone regions of, the world. In India, cyclones occur usually between April and May and also between October and December. The eastern coastline is more, prone to cyclones as it is hit by about 80 percent of the total cyclones generated in the region., , It is evident today that human activities are responsible for accelerating the frequency and, severity of natural disasters. Natural occurrences, such as floods, earthquakes, cyclones, etc. will, always occur. They are a part of the environment that we live in. However destruction from, natural hazards can be minimized by the presence of a well functioning warning system combined with preparedness on part of the, community that will be affected. Thus though, traditionally disaster management consisted primarily of reactive mechanisms, the past few, years have witnessed a gradual shift towards a, more proactive, mitigation based approach., , Droughts are a perennial feature in some states, of India. Sixteen percent of the country’s total, area is drought prone. Drought is a significant, environmental problem as it is caused by a lower, than average rainfall over a long period of time., Most of the drought prone areas identified by, the Government lie in the arid and semi-arid, areas of the country., Earthquakes are considered to be one of the, most destructive natural hazards. The impact of, , Till very recently the approach towards dealing, with natural disasters has been post disaster, management involving problems such as evacuation, warnings, communications, search and, rescue, fire-fighting, medical and psychiatric, assistance, provision of relief, shelter, etc. After, the initial trauma and the occurrence of the, natural disaster is over and reconstruction and, rehabilitation is done by people, NGOs and the, Government, its memories are relegated to history., , Disaster management is a multidisciplinary area, in which a wide range of issues that range from, forecasting, warning, evacuation, search and, rescue, relief, reconstruction and rehabilitation, are included. It is also multi-sectoral as it involves, administrators, scientists, planners, volunteers, and communities. These roles and activities span, Environmental Studies for Undergraduate Courses, , 156, , Chapter5.p65, , this phenomenon occurs with so little warning, that it is almost impossible to make preparations against damages and collapse of buildings., About 50 to 60 percent of India is vulnerable to, seismic activity of varying intensities. Most of, the vulnerable areas are located in the Himalayan and sub-Himalayan regions., , 156, , 4/9/2004, 5:09 PM
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the pre-disaster, during disaster and post disaster plans. Since their activities are complementary as well as supplementary to each other there, is a critical need for coordinating these activities., In order to transfer the benefits of scientific research and development to the communities, links must be developed between scientific communities and field agencies. Coordination between Government agencies and NGOs needs, to be built up so that overlap of activities may, be avoided and linkages between the Government and communities are established., Today we have a range of early warning systems for a range of natural hazards. Although, they are more accurate than before and can help, in prediction it is not enough to ensure communities are safe from disasters. This is where disaster mitigation can play an important role., Mitigation means lessening the negative impact, of the natural hazards. It is defined as sustained, action taken to reduce long term vulnerability, of human life and property to natural hazards., While the preparatory, response and the recovery phases of emergency management relate, to specific events, mitigation activities have the, potential to produce repetitive benefits over, time., Certain guidelines if followed can result in an, effective mitigation program., •, , Pre-disaster mitigation can help in ensuring, faster recovery from the impacts of disasters., , •, , Mitigation measures must ensure protection of the natural and cultural assets of the, community., , •, , Hazard reduction methods must take into, account the various hazards faced by the, affected community and their desires and, priorities., , •, , Any mitigation program must also ensure, effective partnership between Government,, scientific, private sector, NGOs and the community., , The main elements of a mitigation strategy are, as follows:, , Risk assessment and Vulnerability analysis, This involves identification of hot spot areas of, prime concern, collection of information on past, natural hazards, information of the natural ecosystems and information on the population and, infrastructure. Once this information is collected, a risk assessment should be done to determine, the frequency, intensity, impact and the time, taken to return to normalcy after the disaster., The assessment of risk and vulnerabilities will, need to be revised periodically. A regular mechanism will therefore have to be established for, this. The use of Geographical Information Systems (GIS) a computer program can be a valuable tool in this process as the primary data can, be easily updated and the corresponding assessments can be made., , Applied research and technology transfer, There is a need to establish or upgrade observation equipment and networks, monitor the, hazards properly, improve the quality of forecasting and warning, disseminate information, quickly through the warning systems and undertake disaster simulation exercises., Thus space technologies such as remote sensing, satellite communications and Global Positioning Systems have a very important role to, play. Government organizations like ISRO (Indian Space Research Organization) can play a, vital role. Similarly Government organizations, the National Building Research Organization, the, Meteorological Department, Irrigation Department, etc. can undertake applied research for, devising locale specific mitigation strategies in, , Pollution, , Chapter5.p65, , 157, , 157, , 4/9/2004, 5:09 PM
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collaboration with educational institutions or, Universities., Such steps could lead to the formulation of locale specific mitigation measures. A combination of scientific knowledge and expertise with, the community based mitigation measures, would not only enhance the database but would, also form the basis of a successful mitigation, strategy., , Public awareness and training, One of the most critical components of a mitigation strategy is the training to be imparted to, the officials and staff of the various departments, involved at the state and the district level. This, enables sharing of information and methodology. The success of a mitigation strategy will, depend to a large extent on the inter-sectional,, inter-departmental coordination and efficient, teamwork. Thus a training program that is designed after assessment of gaps in knowledge,, skills and attitude with respect to the various, tasks that need to be undertaken is a vital component., , Institutional mechanisms, The most important need at the National level, is to strengthen or develop the capacity to undertake disaster mitigation strategies. There is, a need to emphasize on proactive and pre-disaster measures rather than post disaster response. It is thus essential to have a permanent, administrative structure which can monitor the, developmental activities across departments and, provides suggestions for necessary mitigation, measures. The National Disaster Management, Center (NDMC) can perform such a task. Professionals like architects, structural engineers,, doctors, chemical engineers who are involved, with management of hazardous chemicals can, be asked to form groups that can design specific mitigation measures., , Landuse planning and regulations, Long term disaster reduction efforts should aim, at promoting appropriate land-use in the disaster prone areas. Separation of industrial areas, from residential areas, maintaining wetlands as, buffer zones for floods, creation of public awareness of proper land practices and formation of, land-use policies for long term sustainable development is imperative., , Hazard resistant design and construction, In areas that are prone to disasters protection, can be enhanced by careful selection of sites, and the way the buildings are built. Thus it is, essential to promote the knowledge of disaster, resistant construction techniques and practices, among engineers, architects and technical personnel., , Structural and Constructional reinforcement of, existing buildings, It is also possible to reduce the vulnerability of, existing buildings through minor adaptations or, alterations thereby ensuring their safety. This can, be done by insertion of walls on the outside of, the building, buttresses, walls in the interior of, the building, portico fill-in-walls, specially anEnvironmental Studies for Undergraduate Courses, , 158, , Chapter5.p65, , Incentives and resources for mitigation, To a very large extent the success of mitigation, programs will depend upon the availability of, continued funding. There is thus a need to develop mechanisms to provide stable sources of, funding for all mitigation programs. This will, include incentives for relocation of commercial, and residential activities outside the disaster, prone areas. Housing finance companies should, make it mandatory for structures in such hazard prone areas to follow special building specifications. The introduction of disaster linked, insurance should be explored and should cover, not only life but also household goods, cattle,, structures and crops., , 158, , 4/9/2004, 5:09 PM
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chored frames, covering of columns and beams,, construction of new frame system, placing residential electrical equipment above flood level,, designing water storage tanks to be able to withstand cyclonic winds, earthquakes and floods,, etc., , •, , Prevention of over-bank spilling by the construction of embankments and floodwalls., , •, , Improvement of flow conditions in the channel and anti-erosion measures., , •, , Improved drainage., , Floods and mitigation measures, The lower plain regions of India in particular, Bihar, Uttar Pradesh and West Bengal in respect, of the Ganga and Assam in respect of the, Brahmaputra suffer from the adverse effects of, floods every year. The Ganga Brahmaputra basin receives maximum run off within the three, monsoon months. Based on hydrological studies carried out, it is estimated that only 18 percent of the rainwater can be stored in dams,, reservoirs, etc. while 82 percent of the rainwater flows through rivers ultimately into the sea., Floods are therefore a recurring phenomenon, in our country., Floods can be caused by natural, ecological or, anthropogenic factors either individually or as a, combined result. Anthropogenic activities such, as deforestation and shifting cultivation can also, contribute to floods. Forests on the hill slopes, normally exert a sponge effect soaking up the, abundant rainfall and storing it before releasing it in small amounts over a period of time., However when the forests are cleared the rivers turn muddy and swollen during the wet, monsoon season and run dry later on in the year, during the drier periods. An increasing proportion of the rainfall is therefore released shortly, after precipitation in the form of floods., The mitigation measures for floods include both, structural and non-structural measures. The, structural measures include:, •, , Reservoirs for impounding monsoon flows, to be released in a regulated manner after, the peak flood flow passes., , The non-structural measures include:, •, , Flood plain management such as Flood Plain, Zoning and Flood Proofing including Disaster Preparedness, , •, , Maintaining wetlands, , •, , Flood forecasting and warning services, , •, , Disaster relief, flood fighting and public, health measures, , •, , Flood insurance, , Earthquakes and mitigation measures, It has been several years since the earthquake, struck Gujarat on January 26, 2001. In these, years rehabilitation has been done on a massive, scale. Gujarat’s experience has taught that building shelters with less vulnerability to earthquakes, should also take into consideration the specific, needs of the victims instead of being a top down, approach. The role of NGOs in this is very important. Their strength lies in their manpower,, informality in operations and valuable human, resources. Their ability to reach out to the community and sensitivity to local traditions is an, asset in such situations. A report on the various, initiatives in Gujarat reported in Down to Earth, (Vol 12, No. 2) by Mihir Bhatt throws light on, the various developments that have taken place, after the earthquake. According to the report, the initiatives of the International Fund for, , Pollution, , Chapter5.p65, , 159, , 159, , 4/9/2004, 5:09 PM
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Agriculture Development in supporting the Self, Employed Women’s Association and the, Government’s initiative in community based livelihood security for earthquakes and drought victims have the potential to shape future disaster, response and development projects in Gujarat., Similarly the Gujarat Woman’s Economic Development Corporation initiative in reviving, women’s businesses after the calamity also provides many practical lessons in regenerating local economies and artisan markets. This project, supported by the Asian Development Bank, puts, premium on investments in income generation, and asset building after a natural disaster. The, farming kits provided to affected farmers by, Gujarat’s agriculture ministry is also showing, promising results after two seasons. The author, however states that coordination between Government, local NGOs and local community initiatives both for rescue as well as rehabilitation, needs to be strengthened as this can cause delays, overlaps and waste of relief material and, efforts., , Cyclones and mitigation measures, Tropical cyclones are the worst natural hazards, in the tropics. They are large revolving vortices, in the atmosphere extending horizontally from, 150 to1000 km and vertically from the surface, to 12 to 14 km. These are intense low-pressure, areas. Strong winds spiraling anti clockwise in, the Northern Hemisphere blow around the cyclone center at the lower level. At the higher, levels the sense of rotation is just opposite to, that at the lower level. They generally move 300, to 5000 km per day over the ocean. While moving over the ocean they pick up energy from, the warm water of the ocean and some of them, grow into a devastating intensity. On an average about 5 to 6 tropical cyclones form in the, Bay of Bengal and the Arabian Sea every year, out of which 2 to 3 may be severe. More cyclones form in the Bay of Bengal than in the, Arabian Sea. The main dangers from cyclones, , Although one cannot control cyclones, the effects of cyclones can be mitigated through effective and efficient mitigation policies and, strategies. A brief description of the same is, given below., , Installation of early warning systems: Such systems fitted along the coastlines can greatly assist forecasting techniques thus helping in early, evacuation of people in the storm surge areas., Developing communication infrastructure: Communication plays a vital role in cyclone disaster, mitigation and yet this is one of the first services that gets disrupted during cyclones. Amateur Radio has today emerged as a second line, unconventional communications systems and is, an important tool for disaster mitigation., Developing shelter belts: Shelter belts with plantations of trees can act as effective wind and, tide breakers. Apart from acting as effective, windbreakers and protecting soil crops from, being damaged they prevent soil erosion., Developing community cyclone shelters: Cyclone, shelters at strategic locations can help minimizing the loss of human life. In the normal course, these shelters can be used as public utility buildings., , Construction of permanent houses: There is a, need to build appropriately designed concrete, houses that can withstand high winds and tidal, waves., Training and education: Public awareness programs that inform the population about their, response to cyclone warnings and preparedness, can go a long way in reducing causalities., Environmental Studies for Undergraduate Courses, , 160, , Chapter5.p65, , are very strong winds, torrential rains and high, storm tides. Most of the causalities are caused, by coastal inundation by storm tides. This is often followed by heavy rainfall and floods. Storm, surges cause the greatest destruction., , 160, , 4/9/2004, 5:09 PM
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Landuse control and settlement planning: No, residential and industrial units should be ideally, permitted in the coastal belt of 5 km from the, sea as it is the most vulnerable belt. No further, growth of settlements in this region should allowed. Major settlements and other important, establishments should be located beyond 10 km, from the sea., , Landslides and mitigation measures, Landslides are recurring phenomena in the Himalayan region. In the recent years however, intensive construction activity and the destabilizing forces of nature have aggravated the problem. Landslides occur as a result of changes on, a slope, sudden or gradual, either in its composition, structure, hydrology or vegetation. The, changes can be due to geology, climate, weathering, land-use and earthquakes., A significant reduction in the hazards caused, by landslides can be achieved by preventing the, exposure of population and facilities to landslides, and by physically controlling the landslides. Developmental programs that involve modification, of the topography, exploitation of natural resources and change in the balance load on the, ground should not be permitted. Some critical, measures that could be undertaken to prevent, further landslides are drainage measures, erosion control measures such a bamboo check, dams, terracing, jute and coir netting and rockfall control measures such as grass plantation,, vegetated dry masonry wall, retaining wall and, most importantly preventing deforestation and, improving afforestation., Disasters cannot be totally prevented. However, early warning systems, careful planning and preparedness on part of the vulnerable community, would help in minimizing the loss of life and, property due to these disasters., , Pollution, , Chapter5.p65, , 161, , 161, , 4/9/2004, 5:09 PM
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UNIT 5:, , Pollution, , Chapter5.p65, , 5.1 DEFINITION, , 112, , 5.2 CAUSES, EFFECTS AND CONTROL MEASURES OF:, , 113, , 5.2.1 Air Pollution, , 113, , 5.2.2 Water Pollution, , 123, , 5.2.3 Soil Pollution, , 131, , 5.2.4 Marine Pollution, , 135, , 5.2.5 Noise Pollution, , 140, , 5.2.6 Thermal Pollution, , 142, , 5.2.7 Nuclear hazards, , 143, , 5.3 SOLID WASTE MANAGEMENT: CAUSES, EFFECTS AND CONTROL MEASURES, OF URBAN AND INDUSTRIAL WASTE, , 145, , 5.4 ROLE OF INDIVIDUALS IN POLLUTION PREVENTION, , 150, , 5.5 POLLUTION CASE STUDIES, , 153, , 5.6 DISASTER MANAGEMENT: FLOODS, EARTHQUAKES, CYCLONES, LANDSLIDES, , 156, , Pollution, , 111, , 111, , 4/9/2004, 5:09 PM
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‘We spray our elms, and the following spring,, trees are silent of robin song, not because, we sprayed the robins directly but because, the poison traveled step by step through the, now familiar elm-earthworm-robin cycle’, – Rachael Carson, , book has inspired controversy and has initiated, a major change in thinking about the safety of, using pesticides and other toxic chemicals., , This quotation appeared in Rachael Carson’s, book entitled Silent Spring. In the years following the publication of Silent Spring in 1962, the, , Pollution is the effect of undesirable changes in, our surroundings that have harmful effects on, plants, animals and human beings. This occurs, Environmental Studies for Undergraduate Courses, , 112, , Chapter5.p65, , 5.1 DEFINITION, , 112, , 4/9/2004, 5:09 PM
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when only short-term economic gains are made, at the cost of the long-term ecological benefits, for humanity. No natural phenomenon has led, to greater ecological changes than have been, made by mankind. During the last few decades, we have contaminated our air, water and land, on which life itself depends with a variety of, waste products., Pollutants include solid, liquid or gaseous substances present in greater than natural abundance produced due to human activity, which, have a detrimental effect on our environment., The nature and concentration of a pollutant, determines the severity of detrimental effects, on human health. An average human requires, about 12 kg of air each day, which is nearly 12, to15 times greater than the amount of food we, eat. Thus even a small concentration of pollutants in the air becomes more significant in comparison to the similar levels present in food., Pollutants that enter water have the ability to, spread to distant places especially in the marine, ecosystem., From an ecological perspective pollutants can, be classified as follows:, Degradable or non-persistent pollutants: These, can be rapidly broken down by natural processes. Eg: domestic sewage, discarded vegetables, etc., Slowly degradable or persistent pollutants: Pollutants that remain in the environment for many, years in an unchanged condition and take decades or longer to degrade. Eg: DDT and most, plastics., Non-degradable pollutants: These cannot be, degraded by natural processes. Once they are, released into the environment they are difficult, to eradicate and continue to accumulate. Eg:, toxic elements like lead or mercury., , 5.2 CAUSES, EFFECTS AND CONTROL MEASURES OF POLLUTION, 5.2.1 Air Pollution, History of air pollution: The origin of air pollution on the earth can be traced from the times, when man started using firewood as a means, of cooking and heating. Hippocrates has mentioned air pollution in 400 BC. With the discovery and increasing use of coal, air pollution, became more pronounced especially in urban, areas. It was recognized as a problem 700 years, ago in London in the form of smoke pollution,, which prompted King Edward I to make the first, antipollution law to restrict people from using, coal for domestic heating in the year 1273. In, the year 1300 another Act banning the use of, coal was passed. Defying the law led to imposition of capital punishment. In spite of this air, pollution became a serious problem in London, during the industrial revolution due to the use, of coal in industries. The earliest recorded major disaster was the ‘London Smog’ that occurred, in 1952 that resulted in more than 4000 deaths, due to the accumulation of air pollutants over, the city for five days., In Europe, around the middle of the 19th century, a black form of the Peppered moth was, noticed in industrial areas. Usually the normal, Peppered moth is well camouflaged on a clean, lichen covered tree. However the peppered pattern was easily spotted and picked up by birds, on the smoke blackened bark of trees in the, industrial area, while the black form remained, well camouflaged. Thus while the peppered, patterned moths were successful in surviving in, clean non-industrial areas, the black coloured, moths were successful in industrial areas. With, the spread of industrialization, it has been observed that the black forms are not only see in, Peppered moth, but also in many other moths., This is a classic case of pollution leading to adaptation., , Pollution, , Chapter5.p65, , 113, , 113, , 4/9/2004, 5:09 PM
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Air pollution began to increase in the beginning, of the twentieth century with the development, of the transportation systems and large-scale use, of petrol and diesel. The severe air quality problems due to the formation of photochemical, smog from the combustion residues of diesel, and petrol engines were felt for the first time in, Los Angeles. Pollution due to auto-exhaust remains a serious environmental issue in many, developed and developing countries including, India., The Air Pollution Control Act in India was passed, in 1981 and the Motor Vehicle Act for controlling the air pollution, very recently. These laws, are intended to prevent air from being polluted., The greatest industrial disaster leading to serious air pollution took place in Bhopal where, extremely poisonous methyl isocyanide gas was, accidentally released from the Union Carbide’s, pesticide manufacturing plant on the night of, December 3rd 1984. The effects of this disaster, on human health and the soil are felt even today., , Temperature declines with altitude in the troposphere. At the top of the troposphere temperatures abruptly begin to rise. This boundary, where this temperature reversal occurs is called, the tropopause., The tropopause marks the end of the troposphere and the beginning of the stratosphere,, the second layer of the atmosphere. The stratosphere extends from 17 to 48 kilometers above, the earth’s surface. While the composition of, the stratosphere is similar to that of the troposphere it has two major differences. The volume of water vapour here is about 1000 times, less while the volume of ozone is about 1000, times greater. The presence of ozone in the, stratosphere prevents about 99 percent of the, sun’s harmful ultraviolet radiation from reaching the earth’s surface thus protecting humans, from cancer and damage to the immune system. This layer does not have clouds and hence, airplanes fly in this layer as it creates less turbulence. Temperature rises with altitude in the, stratosphere until there is another reversal. This, point is called the stratopause and it marks the, end of the stratosphere and the beginning of, the atmosphere’s next layer, the mesosphere., , Structure of the atmosphere, The atmosphere is normally composed of 79, percent nitrogen, 20 percent oxygen and one, percent as a mixture of carbon dioxide, water, vapour and trace amounts of several other gases, such as neon, helium, methane, krypton, hydrogen and xenon. The general structure of the, atmosphere has several important features that, have relevance to environmental problems. The, atmosphere is divided into several layers., The innermost layer the troposphere extends 17, kilometers above sea level at the equator and, about 8 kilometers over the poles. It contains, about 75 percent of the mass of the earth’s air., The fragility of this layer is obvious from the fact, that if the earth were an apple this particular, layer would be no thicker than an apple’s skin., , Types and sources of Air Pollution, What is air pollution?, Air pollution occurs due to the presence of undesirable solid or gaseous particles in the air in, quantities that are harmful to human health and, the environment. Air may get polluted by natuEnvironmental Studies for Undergraduate Courses, , 114, , Chapter5.p65, , In the mesosphere the temperature decreases, with altitude falling up to –110 oC at the top., Above this is a layer where ionization of the, gases is a major phenomenon, thus increasing, the temperature. This layer is called the thermosphere. Only the lower troposphere is routinely involved in our weather and hence air, pollution. The other layers are not significant in, determining the level of air pollution., , 114, , 4/9/2004, 5:09 PM
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ral causes such as volcanoes, which release ash,, dust, sulphur and other gases, or by forest fires, that are occasionally naturally caused by lightning. However, unlike pollutants from human, activity, naturally occurring pollutants tend to, remain in the atmosphere for a short time and, do not lead to permanent atmospheric change., Pollutants that are emitted directly from identifiable sources are produced both by natural, events (for example, dust storms and volcanic, eruptions) and human activities (emission from, vehicles, industries, etc.). These are called primary pollutants. There are five primary pollutants that together contribute about 90 percent, of the global air pollution. These are carbon, oxides (CO and CO2), nitrogen oxides, sulfur, oxides, volatile organic compounds (mostly hydrocarbons) and suspended particulate matter., Pollutants that are produced in the atmosphere, when certain chemical reactions take place, among the primary pollutants are called secondary pollutants. Eg: sulfuric acid, nitric acid, carbonic acid, etc., , Carbon monoxide is a colourless, odorless and, toxic gas produced when organic materials such, as natural gas, coal or wood are incompletely, burnt. Vehicular exhausts are the single largest, source of carbon monoxide. The number of vehicles has been increasing over the years all over, the world. Vehicles are also poorly maintained, and several have inadequate pollution control, equipment resulting in release of greater, amounts of carbon monoxide. Carbon monoxide is however not a persistent pollutant. Natural processes can convert carbon monoxide to, other compounds that are not harmful. Therefore the air can be cleared of its carbon monoxide if no new carbon monoxide is introduced, into the atmosphere., Sulfur oxides are produced when sulfur containing fossil fuels are burnt., , Nitrogen oxides are found in vehicular exhausts., Nitrogen oxides are significant, as they are involved in the production of secondary air pollutants such as ozone., Hydrocarbons are a group of compounds consisting of carbon and hydrogen atoms. They either evaporate from fuel supplies or are, remnants of fuel that did not burn completely., Hydrocarbons are washed out of the air when, it rains and run into surface water. They cause, an oily film on the surface and do not as such, cause a serious issue until they react to form, secondary pollutants. Using higher oxygen concentrations in the fuel-air mixture and using, valves to prevent the escape of gases, fitting of, catalytic converters in automobiles, are some of, the modifications that can reduce the release, of hydrocarbons into the atmosphere., Particulates are small pieces of solid material (for, example, smoke particles from fires, bits of asbestos, dust particles and ash from industries), dispersed into the atmosphere. The effects of, particulates range from soot to the carcinogenic, (cancer causing) effects of asbestos, dust particles and ash from industrial plants that are dispersed into the atmosphere. Repeated exposure, to particulates can cause them to accumulate, in the lungs and interfere with the ability of the, lungs to exchange gases., Lead is a major air pollutant that remains largely, unmonitored and is emitted by vehicles. High, lead levels have been reported in the ambient, air in metropolitan cities. Leaded petrol is the, primary source of airborne lead emissions in Indian cities., Pollutants are also found indoors from infiltration of polluted outside air and from various, chemicals used or produced inside buildings., Both indoor and outdoor air pollution are equally, harmful., , Pollution, , Chapter5.p65, , 115, , 115, , 4/9/2004, 5:09 PM
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Types of particulates, Term, , Meaning, , Examples, , Aerosol, , General term for particles suspended in air, , Sprays from pressurized cans, , Mist, , Aerosol consisting of liquid droplets, , Sulfuric acid mist, , Dust, , Aerosol consisting of solid particles that are blown into, the air or are produced from larger particles by grinding, them down, , Dust storm, , Smoke, , Aerosol consisting of solid particles or a mixture of solid, and liquid particles produced by chemical reaction such, as fires, , Cigarette smoke, smoke, from burning garbage, , Fume, , Generally means the same as smoke but often applies, specifically to aerosols produced by condensation of hot, vapors of metals., , Zinc/lead fumes, , Plume, , Geometrical shape or form of the smoke coming out of, a chimney, , Fog, , Aerosol consisting of water droplets, , Smog, , Term used to describe a mixture of smoke and fog., , What happens to pollutants in the atmosphere?, Once pollutants enter the troposphere they are, transported downwind, diluted by the large volume of air, transformed through either physical, or chemical changes or are removed from the, atmosphere by rain during which they are attached to water vapour that subsequently forms, rain or snow that falls to the earth’s surface., The atmosphere normally disperses pollutants, by mixing them in the very large volume of air, that covers the earth. This dilutes the pollutants, to acceptable levels. The rate of dispersion however varies in relation to the following aspects:, , However on a still evening, the process is reversed. An hour or two before sunset after a, sunny day, the ground starts to lose heat and, the air near the ground begins to cool rapidly., Due to the absence of wind, a static layer of, cold air is produced as the ground cools. This in, turn induces condensation of fog. The morning, sun cannot initially penetrate this fog layer. The, Environmental Studies for Undergraduate Courses, , 116, , Chapter5.p65, , Topography, Normally as the earth’s surface becomes, warmed by sunlight the layer of air in contact, with the ground is also heated by convection., This warmer air is less dense than the cold air, above it, so it rises. Thus pollutants produced in, the surface layer are effectively dispersed., , 116, , 4/9/2004, 5:09 PM
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cold air being dense cannot rise and is trapped, by the warm air above. It cannot move out of, the area due to the surrounding hills. The topographic features resemble a closed chemical reactor in which the pollutants are trapped. This, condition often continues through the cool night, and reaches its maximum intensity before sunrise. When the morning sun warms the ground, the air near the ground also warms up and rises, within an hour or two. This may be broken up, by strong winds. In cold regions this situation, can persist for several days. Such a situation is, known as smog (smoke + fog)., , other industrial establishments. This used to lead, to the generation of high levels of smoke containing sulphur oxides. Due to a sudden adverse, meteorological condition air pollutants like, smoke and sulphur oxides started to build-up in, the atmosphere. The white fog accumulated, over the city turned black forming a ‘pea-soup’, smog with almost zero visibility. Within two days, of the formation of this smog, people started, suffering from acute pulmonary disorders which, caused irritation of bronchi, cough, nasal discharges, sore throat, vomiting and burning sensations in the eyes. This event lead to several, deaths., , Meteorological conditions, The velocity of the wind affects the dispersal of, pollutants. Strong winds mix polluted air more, rapidly with the surrounding air diluting the, pollutants rapidly. When wind velocity is low, mixing takes place and the concentration of, pollutants remains high., , The most well known example is that of the, ‘London Smog’ that occurred in 1952. The city, used large quantities of sulphur containing coal, for domestic heating that released smoke, along, with smoke from thermal power plants and, Pollution, , Chapter5.p65, , 117, , 117, , 4/9/2004, 5:09 PM
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When sulphur dioxide and nitrogen oxides are, transported by prevailing winds they form secondary pollutants such as nitric acid vapour,, droplets of sulfuric acid and particles of sulphate, and nitrate salts. These chemicals descend on, the earth’s surface in two forms: wet (as acidic, rain, snow, fog and cloud vapour) and dry (as, acidic particles). The resulting mixture is called, acid deposition, commonly called acid rain., Acid deposition has many harmful effects especially when the pH falls below 5.1 for terrestrial, systems and below 5.5 for aquatic systems. It, contributes to human respiratory diseases such, as bronchitis and asthma, which can cause premature death. It also damages statues, buildings, metals and car finishes. Acid deposition, can damage tree foliage directly but the most, serious effect is weakening of trees so they become more susceptible to other types of damage. The nitric acid and the nitrate salts in acid, deposition can lead to excessive soil nitrogen, levels. This can over stimulate growth of other, plants and intensify depletion of other important soil nutrients such as calcium and magnesium, which in turn can reduce tree growth and, vigour., , Effects of air pollution on living organisms, Our respiratory system has a number of mechanisms that help in protecting us from air pollution. The hair in our nose filters out large, particles. The sticky mucus in the lining of the, upper respiratory tract captures smaller particles, and dissolves some gaseous pollutants. When, the upper respiratory system is irritated by pollutants sneezing and coughing expel contaminated air and mucus. Prolonged smoking or, exposure to air pollutants can overload or breakdown these natural defenses causing or contributing to diseases such as lung cancer,, asthma, chronic bronchitis and emphysema. Elderly people, infants, pregnant women and, people with heart disease, asthma or other res-, , Cigarette smoking is responsible for the greatest exposure to carbon monoxide. Exposure to, air containing even 0.001 percent of carbon, monoxide for several hours can cause collapse,, coma and even death. As carbon monoxide remains attached to hemoglobin in blood for a, long time, it accumulates and reduces the oxygen carrying capacity of blood. This impairs perception and thinking, slows reflexes and causes, headaches, drowsiness, dizziness and nausea., Carbon monoxide in heavy traffic causes headaches, drowsiness and blurred vision., Sulfur dioxide irritates respiratory tissues., Chronic exposure causes a condition similar to, bronchitis. It also reacts with water, oxygen and, other material in the air to form sulfur-containing acids. The acids can become attached to, particles which when inhaled are very corrosive, to the lung., Nitrogen oxides especially NO2 can irritate the, lungs, aggravate asthma or chronic bronchitis, and also increase susceptibility to respiratory, infections such as influenza or common colds., Suspended particles aggravate bronchitis and, asthma. Exposure to these particles over a long, period of time damages lung tissue and contributes to the development of chronic respiratory disease and cancer., Many volatile organic compounds such as (benzene and formaldehyde) and toxic particulates, (such as lead, cadmium) can cause mutations,, reproductive problems or cancer. Inhaling ozone,, a component of photochemical smog causes, coughing, chest pain, breathlessness and irritation of the eye, nose and the throat., , Environmental Studies for Undergraduate Courses, , 118, , Chapter5.p65, , piratory diseases are especially vulnerable to air, pollution., , 118, , 4/9/2004, 5:09 PM
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centration can produce dramatic effects on life, on earth., , Effects on plants, When some gaseous pollutants enter leaf pores, they damage the leaves of crop plants. Chronic, exposure of the leaves to air pollutants can break, down the waxy coating that helps prevent excessive water loss and leads to damage from, diseases, pests, drought and frost. Such exposure interferes with photosynthesis and plant, growth, reduces nutrient uptake and causes, leaves to turn yellow, brown or drop off altogether. At a higher concentration of sulphur, dioxide majority of the flower buds become stiff, and hard. They eventually fall from the plants,, as they are unable to flower., Prolonged exposure to high levels of several air, pollutants from smelters, coal burning power, plants and industrial units as well as from cars, and trucks can damage trees and other plants., , Effects of air pollution on materials, Every year air pollutants cause damage worth, billions of rupees. Air pollutants break down, exterior paint on cars and houses. All around, the world air pollutants have discoloured irreplaceable monuments, historic buildings, marble, statues, etc., , Effects of air pollution on the stratosphere, The upper stratosphere consists of considerable, amounts of ozone, which works as an effective, screen for ultraviolet light. This region called the, ozone layer extends up to 60 kms above the, surface of the earth. Though the ozone is, present upto 60 kms its greatest density remains, in the region between 20 to 25 kms. The ozone, layer does not consist of solely ozone but a mixture of other common atmospheric gases. In the, most dense ozone layer there will be only one, ozone molecule in 100,000 gas molecules., Therefore even small changes in the ozone con-, , The total amount of ozone in a ‘column’ of air, from the earth’s surface upto an altitude of 50, km is the total column ozone. This is recorded, in Dobson Units (DU), a measure of the thickness of the ozone layer by an equivalent layer, of pure ozone gas at normal temperature and, pressure at sea level. This means that 100, DU=1mm of pure ozone gas at normal temperature and pressure at sea level., Ozone is a form of oxygen with three atoms, instead of two. It is produced naturally from the, photodissociation of oxygen gas molecules in, the atmosphere. The ozone thus formed is constantly broken down by naturally occurring processes that maintain its balance in the ozone, layer. In the absence of pollutants the creation, and breakdown of ozone are purely governed, by natural forces, but the presence of certain, pollutants can accelerate the breakdown of, ozone. Though it was known earlier that ozone, shows fluctuations in its concentrations which, may be accompanied sometimes with a little, ozone depletion, it was only in 1985 that the, large scale destruction of the ozone also called, the Ozone Hole came into limelight when some, British researchers published measurements, about the ozone layer., Soon after these findings a greater impetus was, given to research on the ozone layer, which, convincingly established that CFC’s were leading to its depletion. These CFCs (chloro-flurocarbons) are extremely stable, non-flammable,, non-toxic and harmless to handle. This makes, them ideal for many industrial applications like, aerosols, air conditioners, refrigerators and fire, extinguishers. Many cans, which give out foams, and sprays, use CFCs. (eg: perfumes, room fresheners, etc.) CFCs are also used in making foams, for mattresses and cushions, disposable, Styrofoam cups, glasses, packaging material for, insulation, cold storage etc. However their sta-, , Pollution, , Chapter5.p65, , 119, , 119, , 4/9/2004, 5:09 PM
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bility also gives them a long life span in the atmosphere., Halons are similar in structure to the CFCs but, contain bromine atoms instead of chlorine. They, are more dangerous to the ozone layer than, CFCs. Halons are used as fire extinguishing, agents as they do not pose a harm to people, and equipment exposed to them during fire, fighting., The CFCs and the halons migrate into the upper atmosphere after they are released. As they, are heavier than air they have to be carried by, air currents up to just above the lower atmosphere and then they slowly diffuse into the, upper atmosphere. This is a slow process and, can take as long as five to fifteen years. In the, stratosphere unfiltered UV-radiation severs the, chemical bonds releasing chlorine from the rest, of the CFC. This attacks the ozone molecule, resulting in its splitting into an oxygen molecule, and an oxygen atom., Despite the fact that CFCs are evenly distribute, over the globe, the ozone depletion is especially, pronounced over the South Pole due to the extreme weather conditions in the Antarctic atmosphere. The presence of the ice crystals, makes the Cl-O bonding easier. The ozone layer, over countries like Australia, New Zealand, South, Africa and parts of South America is also depleted., India has signed the Montreal Protocol in 1992,, which aims to control the production and consumption of Ozone Depleting Substances., , Ozone depletion-What does it do?, Changes in the ozone layer have serious implications for mankind., Effects on human health: Sunburn, cataract,, aging of the skin and skin cancer are caused by, , Food production: Ultra violet radiation affects, the ability of plants to capture light energy during the process of photosynthesis. This reduces, the nutrient content and the growth of plants., This is seen especially in legumes and cabbage., Plant and animal planktons are damaged by ultra-violet radiation. In zooplanktons (microscopic, animals) the breeding period is shortened by, changes in radiation. As planktons form the basis, of the marine food chain a change in their number and species composition influences fish and, shell fish production., Effect on materials: Increased UV radiation, damages paints and fabrics, causing them to, fade faster., Effect on climate: Atmospheric changes induced by pollution contribute to global warming, a phenomenon which is caused due to the, increase in concentration of certain gases like, carbon dioxide, nitrogen oxides, methane and, CFCs. Observations of the earth have shown, beyond doubt that atmospheric constituents, such as water vapour, carbon dioxide, methane,, nitrogen oxides and Chloro Fluro Carbons trap, heat in the form of infra-red radiation near the, earth’s surface. This is known as the ‘Greenhouse Effect’. The phenomenon is similar to, what happens in a greenhouse. The glass in a, greenhouse allows solar radiation to enter which, is absorbed by the objects inside. These objects, radiate heat in the form of terrestrial radiation,, which does not pass out through the glass. The, heat is therefore trapped in the greenhouse increasing the temperature inside and ensuring, the luxuriant growth of plants., Environmental Studies for Undergraduate Courses, , 120, , Chapter5.p65, , increased ultra-violet radiation. It weakens the, immune system by suppressing the resistance, of the whole body to certain infections like, measles, chicken pox and other viral diseases, that elicit rash and parasitic diseases such as, malaria introduced through the skin., , 120, , 4/9/2004, 5:09 PM
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Green House Effect, , There could be several adverse effects of global, warming., •, , With a warmer earth the polar ice caps will, melt causing a rise in ocean levels and flooding of coastal areas., , •, , In countries like Bangladesh or the Maldives, this would be catastrophic. If the sea level, rises by 3m., Maldives will disappear completely beneath the waves., , ane are trapped beneath the frozen soil of, Alaska. When the permafrost melts the, methane that will be released can accelerate the process of global warming., , Control measures for air pollution, , •, , The rise in temperature will bring about a, fall in agricultural produce., , •, , Changes in the distribution of solar energy, can bring about changes in habitats. A previously productive agricultural area will suffer severe droughts while rains will fall in, locations that were once deserts. This could, bring about changes in the species of natural plants, agricultural crops, insects, livestock and micro-organisms., , •, , In the polar regions temperature rises, caused by global warming would have disastrous effects. Vast quantities of meth-, , Air pollution can be controlled by two fundamental approaches: preventive techniques and, effluent control., One of the effective means of controlling air, pollution is to have proper equipment in, place. This includes devices for removal of pollutants from the flue gases though scrubbers,, closed collection recovery systems through, which it is possible to collect the pollutants, before they escape, use of dry and wet collectors, filters, electrostatic precipitators, etc., Providing a greater height to the stacks can, help in facilitating the discharge of pollutants, as far away from the ground as possible. Industries should be located in places so as to minimize the effects of pollution after considering, the topography and the wind directions., Substitution of raw material that causes more, , Pollution, , Chapter5.p65, , 121, , 121, , 4/9/2004, 5:09 PM
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pollution with those that cause less pollution can, be done., , Air pollution in India, The World health Organization (WHO) which, rates only mega cities of the world has rated, Delhi the fourth most polluted city ion the world., However compared to other cities in India, Delhi, is not at the top of the list of polluted cities. Our, country has several pollution hotspots. The recent release from the Central Pollution Control, Board (CPCB), Parivesh, January 2003 states that, Ahmedabad’s air is most noxious flowed by, Kanpur, Solapur and Lucknow with small particulate levels (PM10) 3-4 times the standard of, 60 microgram per cubic meter (mg/m3). The report has ranked 29 cities according to Respirable Particulate Matter (RSPM) levels recorded, during the year 2000. This report thus confirms, the fact that Indian cities show high particulate, pollution with 14 cities hitting critical levels., Nitrogen dioxide levels in most major cities are, generally close to the acceptable annual standard of 60 mg/m3. However sharp increases have, been noticed in a few cities with heavy vehicular traffic and density as in a few locations in, Kolkata and Delhi indicating stronger impact of, traffic. The CPCB indicates vehicles as one of, the predominant sources of air pollution. However the impact of hard measures implemented, in Delhi over the last few years such as introduction of Euro II standards, lowering the sulphur content in fuel to 500 ppm and, implementing Compressed Natural Gas program, has succeeded in improving the quality of air., Rapid urbanization of smaller cities especially, those situated near the big commercial centers, have an enormous increase in traffic load especially in the most polluted segment such as two, and three wheelers and diesel vehicles combined, with poor quality fuel contribute to the deteriorating air quality in a big way., , The Supreme Court also played a vital role protecting the Taj Mahal. Being exposed to sulphur, dioxide and suspended particulate matter, the, Taj had contracted ‘marble cancer’, a fungal, growth that corroded its surface giving it a yellowish tinge. The SPM deposits blackened it. Shri, MC Mehta an environmental lawyer filed a public interest litigation in 1984 expressing concern, over the havoc the polluting units in Agra were, wreaking on the Taj Mahal. Twelve years later, the Supreme Court ordered 292 industries in, the vicinity to either adopt pollution control, measures or shut down. It also made it mandatory for these units to either switch over to ecofriendly fuels like natural gas or shift out of the, area., , Air quality monitoring, India does not presently have a well established, system of monitoring air pollution. When air, quality monitoring began in India in the late, 1960s planners focused only on a few pollutants namely sulphur dioxide, nitrogen oxides and, suspended particulate matter. Other pollutants, such as carbon monoxide and lead were monitored only on a limited scale. The threat from, other air toxins such as benzene, ozone, other, small particulates is not known as these are not, monitored at all. A database on ambient air, quality in Indian cities has been prepared by the, monitoring networks of the National Environmental Engineering Research Institute (NEERI),, Nagpur. The Central Pollution Control Board, (CPCB) initiated its own national Ambient Air, Quality Monitoring (NAAQM) program in 1985., Environmental Studies for Undergraduate Courses, , 122, , Chapter5.p65, , It is alarming to note that residential locations, in India are fast outpacing industrial locations in, air pollution implying that vehicular fumes are, responsible for this trend. The Supreme Court’s, order of April 5, 2002 has directed the Central, Government for an action plan for other polluted cities. Absence of any local initiatives for, action and delay in air pollution control measures will only make the situation worse., , 122, , 4/9/2004, 5:09 PM
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Ambient air quality standards in India developed by the Central Pollution Control Board, Area Category, , SPM µg/m3, , SO2 µg/m3, , Co µg/m3, , NOx µg/m3, , Industrial and mixed use, , 500, , 120, , 5000, , 120, , Residential and rural, , 200, , 80, , 2000, , 80, , Sensitive, , 100, , 3, , 1000, , 30, , Data to the NAAQM is supplied by the respective state pollution control boards, which is then, transmitted to the CPCB. Experts feel that the, present air quality-monitoring network cannot, capture the true profile of urban air pollution, due to the lack of adequate monitoring stations., Moreover critical toxins have still not been included in the list of pollutants to be monitored., , Legal aspects of air pollution control in India, The Air (Prevention and Control of Pollution) Act, was legislated in 1981. The Act provided for, prevention, control and abatement of air pollution. In areas notified under this Act no industrial pollution causing activity could come up, without the permission of the concerned State, Pollution Control Board. But this Act was not, strong enough to play a precautionary or a corrective role. After the Bhopal disaster, a more, comprehensive Environment Protection Act, (EPA) was passed in 1986. This Act for the first, time conferred enforcement agencies with necessary punitive powers to restrict any activity that, can harm the environment. To regulate vehicular pollution the Central Motor Vehicles Act of, 1939 was amended in 1989. Following this, amendment the exhaust emission rules for vehicle owners were notified in 1990 and the mass, emission standards for vehicle manufacturers, were enforced in 1991 for the first time. The, mass emission norms have been further revised, for 2000., , Air quality management as a well-defined program has yet to emerge in India. We need a, much more strengthened air quality management with continuous monitoring of air if we, are to have a better quality of air. This would, also need an integrated approach with strict air, pollution control laws. Some of the suggestions, for doing this include:, •, , Putting a greater emphasis on pollution prevention rather than control, , •, , Reducing the use of fossil fuels, , •, , Improving the quality of vehicular fuel, , •, , Increasing the use of renewable energy, , 5.2.2 Water Pollution, Our liquid planet glows like a soft blue sapphire in the hard-edged darkness of space., There is nothing else like it in the solar system. It is because of water., – John Todd, Introduction: Water is the essential element, that makes life on earth possible. Without water there would be no life. We usually take water for granted. It flows from our taps when they, are turned on. Most of us are able to bathe when, we want to, swim when we choose and water, , Pollution, , Chapter5.p65, , 123, , 123, , 4/9/2004, 5:09 PM
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our gardens. Like good health we ignore water, when we have it., Although 71% of the earth’s surface is covered, by water only a tiny fraction of this water is available to us as fresh water. About 97% of the, total water available on earth is found in oceans, and is too salty for drinking or irrigation. The, remaining 3% is fresh water. Of this 2.997% is, locked in ice caps or glaciers. Thus only 0.003%, of the earth’ total volume of water is easily available to us as soil moisture, groundwater, water, vapour and water in lakes, streams, rivers and, wetlands., In short if the world’s water supply were only, 100 litres our usable supply of fresh water would, be only about 0.003 litres (one-half teaspoon)., This makes water a very precious resource. The, future wars in our world may well be fought, over water. By the middle of this century, almost twice as many people will be trying to share, the same amount of fresh water the earth has, today. As freshwater becomes more scarce access to water resources will be a major factor in, determining the economic growth of several, countries around the world., Water availability on the planet: Water that, is found in streams, rivers, lakes, wetlands and, artificial reservoirs is called surface water. Water that percolates into the ground and fills the, pores in soil and rock is called groundwater., Porous water-saturated layers of sand, gravel, or bedrock through which ground water flows, are called aquifers. Most aquifers are replenished naturally by rainfall that percolates downward through the soil and rock. This process is, called natural recharge. If the withdrawal rate, of an aquifer exceeds its natural recharge rate,, the water table is lowered. Any pollutant that is, discharged onto the land above is also pulled, into the aquifer and pollutes the groundwater, resulting in polluted water in the nearby wells., , When the quality or composition of water, changes directly or indirectly as a result of, man’s activities such that it becomes unfit, for any purpose it is said to be polluted., Point sources of pollution: When a source of, pollution can be readily identified because it has, a definite source and place where it enters the, water it is said to come from a point source., Eg. Municipal and Industrial Discharge Pipes., When a source of pollution cannot be readily, identified, such as agricultural runoff, acid rain,, etc, they are said to be non-point sources of, pollution., , Environmental Studies for Undergraduate Courses, , 124, , Chapter5.p65, , India receives most of her rainfall during the, months of June to September due to the seasonal winds and the temperature differences, between the land and the sea. These winds blow, from the opposite directions in the different seasons. They blow into India from the surrounding oceans during the summer season and blow, out from the subcontinent to the oceans during, the winter. The monsoon in India is usually reasonably stable but varies geographically. In some, years the commencement of the rains may be, delayed considerably over the entire country or, a part of it. The rains may also terminate earlier, than usual. They may be heavier than usual over, one part than over another. All these may cause, local floods or drought. However in India even, areas that receive adequate rainfall during the, monsoon suffer from water shortages in the post, monsoon period due to lack of storage facilities., , 124, , 4/9/2004, 5:09 PM
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Sources of Pollution, , Causes of water pollution, There are several classes of common water pollutants. These are disease-causing agents, (pathogens) which include bacteria, viruses, protozoa and parasitic worms that enter water from, domestic sewage and untreated human and, animal wastes. Human wastes contain concentrated populations of coliform bacteria such as, Escherichia coli and Streptococcus faecalis. These, bacteria normally grow in the large intestine of, humans where they are responsible for some, food digestion and for the production of vitamin K. These bacteria are not harmful in low, numbers. Large amounts of human waste in, water, increases the number of these bacteria, which cause gastrointestinal diseases. Other, potentially harmful bacteria from human wastes, may also be present in smaller numbers. Thus, the greater the amount of wastes in the water, the greater are the chances of contracting diseases from them., Another category of water pollutants is oxygen depleting wastes. These are organic, wastes that can be decomposed by aerobic (oxygen requiring) bacteria. Large populations of, bacteria use up the oxygen present in water to, , degrade these wastes. In the process this degrades water quality. The amount of oxygen, required to break down a certain amount of, organic matter is called the biological oxygen, demand (BOD). The amount of BOD in the water is an indicator of the level of pollution. If too, much organic matter is added to the water all, the available oxygen is used up. This causes fish, and other forms of oxygen dependent aquatic, life to die. Thus anaerobic bacteria (those that, do not require oxygen) begin to break down, the wastes. Their anaerobic respiration produces, chemicals that have a foul odour and an unpleasant taste that is harmful to human health., A third class of pollutants are inorganic plant, nutrients. These are water soluble nitrates and, phosphates that cause excessive growth of algae and other aquatic plants. The excessive, growth of algae and aquatic plants due to added, nutrients is called eutrophication. They may interfere with the use of the water by clogging, water intake pipes, changing the taste and, odour of water and cause a buildup of organic, matter. As the organic matter decays, oxygen, levels decrease and fish and other aquatic species die., , Pollution, , Chapter5.p65, , 125, , 125, , 4/9/2004, 5:09 PM
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The quantity of fertilizers applied in a field is, often many times more than is actually required, by the plants. The chemicals in fertilizers and, pesticides pollute soil and water. While excess, fertilizers cause eutrophication, pesticides cause, bioaccumulation and biomagnification. Pesticides which enter water bodies are introduced, into the aquatic food chain. They are then absorbed by the phytoplanktons and aquatic, plants. These plants are eaten by the herbivorous fish which are in turn eaten by the carnivorous fish which are in turn eaten by the water, birds. At each link in the food chain these chemicals which do not pass out of the body are accumulated and increasingly concentrated, resulting in biomagnification of these harmful, substances., , A fourth class of water pollutants is water, soluble inorganic chemicals which are acids,, salts and compounds of toxic metals such as, mercury and lead. High levels of these chemicals can make the water unfit to drink, harm, , Environmental Studies for Undergraduate Courses, , 126, , Chapter5.p65, , One of the effects of accumulation of high levels of pesticides such as DDT is that birds lay, eggs with shells that are much thinner than, normal. This results in the premature breaking, of these eggs, killing the chicks inside. Birds of, prey such as hawks, eagles and other fish eating birds are affected by such pollution. Although DDT has been banned in India for, agricultural use and is to be used only for malaria eradication, it is still used in the fields as it, is cheap., , 126, , 4/9/2004, 5:09 PM
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fish and other aquatic life, reduce crop yields, and accelerate corrosion of equipment that use, this water., Another cause of water pollution is a variety of, organic chemicals, which include oil, gasoline,, plastics, pesticides, cleaning solvents, detergent, and many other chemicals. These are harmful, to aquatic life and human health. They get into, the water directly from industrial activity either, from improper handling of the chemicals in industries and more often from improper and illegal disposal of chemical wastes., Sediment of suspended matter is another, class of water pollutants. These are insoluble particles of soil and other solids that become suspended in water. This occurs when soil is eroded, from the land. High levels of soil particles suspended in water, interferes with the penetration of sunlight. This reduces the photosynthetic, activity of aquatic plants and algae disrupting, the ecological balance of the aquatic bodies., When the velocity of water in streams and rivers decreases the suspended particles settle, down at the bottom as sediments. Excessive, sediments that settle down destroys feeding and, spawning grounds of fish, clogs and fills lakes,, artificial reservoirs etc., Water soluble radioactive isotopes are yet, another source of water pollution. These can, be concentrated in various tissues and organs, as they pass through food chains and food webs., Ionizing radiation emitted by such isotopes can, cause birth defects, cancer and genetic damage., Hot water let out by power plants and industries that use large volumes of water to cool the, plant result in rise in temperature of the local, water bodies. Thermal pollution occurs when, industry returns the heated water to a water, source. Power plants heat water to convert it, into steam, to drive the turbines that generate, electricity. For efficient functioning of the steam, , turbines, the steam is condensed into water after it leaves the turbines. This condensation is, done by taking water from a water body to absorb the heat. This heated water, which is at, least 15oC higher than the normal is discharged, back into the water body. The warm water not, only decreases the solubility of oxygen but, changes the breeding cycles of various aquatic, organisms., Oil is washed into surface water in runoff from, roads and parking lots which also pollutes, groundwater. Leakage from underground tanks, CASE STUDY, One of the worst oil spill disasters that have, occurred is that of the Exxon Valdez. On 24th, march 1989 the Exxon Valdez, a tanker more, than three football fields wide went off, course in a 16 kilometer wide channel in, Prince William Sound near Valdez in Alaska., It hit submerged rocks, creating an environmental disaster. The rapidly spreading oil slick, coated more than 1600 kilometers of shoreline killing between 300,000 and 645,000, water birds and a large number of sea otters, harbor seals, whales and fishes. Exxon, spent $ 2.2. billion directly on the clean-up, operations. However some results of the, cleanup effort showed that where high pressure jets of hot water were used to clean, beaches coastal plants and animals that had, survived the spill were killed. Thus it did more, harm than good. Exxon pleaded guilty in, 1991 and agreed to pay the Federal Government and the state of Alaska $ 1 billion, in fines and civil damages. This $8.5 billion, accident might have been prevented if Exxon, had spent only $22.5 million to fit the tanker, with a double hull-one inside the other. Such, double hulled vessels would be less likely to, rupture and spill their contents. The spill highlighted the need for marine pollution prevention., , Pollution, , Chapter5.p65, , 127, , 127, , 4/9/2004, 5:09 PM
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is another source of pollution. Accidental oil spills, from large transport tankers at sea have been, causing significant environmental damage., , •, , Leakage from underground storage tanks, containing gasoline and other hazardous, substances, , Though accidents such as the Exxon Valdez get, worldwide attention, much more oil is released, as a result of small, regular releases from other, less visible sources. Nearly two thirds of all marine oil pollution comes from three sources: runoff from streets, improper discharge of, lubricating oil from machines or automobile, crankcases and intentional oil discharges that, occur during the loading and unloading of tankers. Oil tankers often use sea water as ballast to, stabilize the ship after they have discharged their, oil. This oil contaminated water is then discharged back into the sea when the tanker is, refilled., , •, , Leachate from landfills, , •, , Poorly designed and inadequately maintained septic tanks, , •, , Mining wastes, , Groundwater pollution: While oil spills are, highly visible and often get a lot of media attention, a much greater threat to human life, comes from our groundwater being polluted, which is used for drinking and irrigation. While, groundwater is easy to deplete and pollute it, gets renewed very slowly and hence must be, used judiciously. Groundwater flows are slow, and not turbulent hence the contaminants are, not effectively diluted and dispersed as compared to surface water. Moreover pumping, groundwater and treating it is very slow and, costly. Hence it is extremely essential to prevent, the pollution of groundwater in the first place., Ground water is polluted due to:, •, , Urban run-off of untreated or poorly treated, waste water and garbage, , •, , Industrial waste storage located above or, near aquifers, , •, , Agricultural practices such as the application of large amounts of fertilizers and pesticides, animal feeding operations, etc. in, the rural sector, , There are two theories that have been put forth, to explain this unusually high content of arsenic, in groundwater. One group of researchers suggested that the cause is natural while the other, stated that the cause is man-made., According to the first hypothesis, arsenic probably originates in the Himalayan headwaters of, the Ganga and the Brahmaputra rivers and has, been lying undisturbed beneath the surface of, Environmental Studies for Undergraduate Courses, , 128, , Chapter5.p65, , Severe cases of arsenic poisoning from contaminated groundwater have been reported from, West Bengal in what is known today as the worst, case of groundwater pollution. The School of, Environmental Sciences, Jadhavpur University,, West Bengal has been involved in the task of, surveying the magnitude of the arsenic problem in West Bengal for the last fourteen years., According to a report in the Down to Earth (Vol., 11, No.22), arsenic poisoning was first noticed, by K C Saha, former professor of dermatology, at the School of Tropical Medicine, Kolkata when, he began to receive patients with skin lesions, that resembled the symptoms of leprosy which, was in reality not leprosy. Since all the patients, were from the district of 24-Parganas, Saha, along with others began to look for the cause, and found it to be arsenic toxicity. Thus groundwater arsenic contamination in West Bengal was, first reported in a local daily newspaper in December 1983 when 63 people from three villages located in different districts were identified, by health officials as suffering from arsenic poisoning., , 128, , 4/9/2004, 5:09 PM
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the region’s deltas for thousands of years in the, thick layers of fine alluvial mud across the banks, of these rivers. Most of the arsenic affected areas of West Bengal lie in the alluvial plains, formed in the quarternary period (last 1.6 million years).The Purulia district of West Bengal is, part of the extensive area of the Precambrian, era (last 570 million year) having metamorphic, rocks and granites with widespread sulphide, mineralisation. Researchers from the UK based, British Geological Survey (BGS) suggested that, their position close to where the river Ganga, enters Bangladesh (geologically) may be the primary source of arsenic in the Bengal alluvium., According to David Kinniburgh project leader, with BGS the main factor is time. The mud in, these areas is thicker, wider and flatter than almost anywhere else on earth. It can thus take, hundreds or thousands of years for underground, water to percolate through the mud before, reaching the sea and thus it absorbs arsenic for, a long period., Other researchers feel that the excess amount, of arsenic in groundwater can be contributed, to by the high rate of groundwater extraction., Their hypothesis called the pyrite oxidation thesis describes how arsenic can get mobilized in, the groundwater. In this hypothesis arsenic is, assumed to be present in certain minerals (pyrites) that are deposited within the aquifer sediments. Due to the lowering of the water table, below the deposits, arseno-pyrite which is oxidized in a zone of the aquifer called the Vadose, zone releases arsenic as arsenic adsorbed on iron, hydroxide. During the subsequent recharge period, iron hydroxide releases arsenic into groundwater. This theory is supported by two, arguments. The first is the intensive irrigation, development in West Bengal using deep tube, wells and shallow tube wells. This method of, extraction, which was exactly in the 20m to, 100m below ground level ensured, increased, contribution of groundwater to irrigation. The, other argument that supports the pyrite oxidation theory is that prior to irrigation develop-, , ment and drinking water supply schemes based, on groundwater there were no reported cases, of arsenic poisoning., Arsenicosis or arsenic toxicity develops after two, to five years of exposure to arsenic contaminated, drinking water depending on the amount of, water consumption and the arsenic concentration in water. Initially the skin begins to darken, (called diffuse melanosis) which later leads to, spotted melanosis when darkened sports begin, to appear on the chest, back and limbs. At a, later stage leucomelanosis sets in and the body, begins to show black and white spots. In the, middle stage of arsenicosis the skin in parts becomes hard and fibrous. Rough, dry skin with, nodules on hands or the soles of feet indicate, severe toxicity. This can lead to the formation, of gangrene and cancer. Arsenic poisoning, brings with it other complications such as liver, and spleen enlargement, cirrhosis of the liver,, diabetes, goiter and skin cancers., , The state of India’s rivers, India has always had a tradition of worshipping, rivers. Most of the rivers in India are named after gods, goddesses or saints. However a large, majority of the Indian population including those, who worship the rivers do not think twice before polluting a river. Urbanization, industrialization, excess withdrawal of water, agricultural, run-off, improper agricultural practices and various religious and social practices all contribute, to river pollution in India. Every single river in, India be it the Ganga, Yamuna, Cauvery or the, Krishna have their own share of problems due, to pollution. Waters from the Ganga and the, Yamuna are drawn for irrigation through the, network of canals as soon as these rivers reach, the plains reducing the amount of water that, flows downstream. What flows in the river is, water from small nalas, and streams that carry, with them sewage and industrial effluents. The, residual freshwater, is unable to dilute the pol-, , Pollution, , Chapter5.p65, , 129, , 129, , 4/9/2004, 5:09 PM
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lutants and the rivers turn into stinking sewers., In spite of data from scientifically competent, studies conducted by the Central Pollution Control Board (CPCB), the Government has not been, able to tackle this issue. Sewage and municipal, effluents account for 75% of the pollution load, in rivers while the remaining 25% is from industrial effluents and non-point pollution, sources., In 1985, India launched the Ganga Action plan, (GAP) the largest ever river clean-up operation, in the country. The plan has been criticized for,, overspending and slow progress. The GAP Phase, II in 1991 included cleaning operations for the, tributaries of the Ganga, ie; the Yamuna, Gomti, and the Damodar. Thus the Yamuna Action Plan, (YAP), Gomti Action Plan and the Damodar Action plan were added., In 1995 the National River Conservation plan, was launched. Under this all the rivers in India, were taken up for clean-up operations. In most, of these plans, attempts have been made to tap, drains, divert sewage to sewage treatment, plants before letting out the sewage into the, rivers. The biggest drawback of these river cleaning programs was that they failed to pin responsibilities as to who would pay for running the, treatment facilities in the long run. With the, power supply being erratic and these plants, being heavily dependent on power, most of, these facilities lie underutilized. Moreover the, problem of river pollution due to agricultural runoff has not been addressed in these programs., NRCP is scheduled to be completed by March, 2005. The approved cost for the plan is Rs., 772.08 crores covering 18 rivers in 10 states including 46 towns. The cost is borne entirely by, the Central Government and the Ministry of, Environment and Forests is the nodal agency that, co-ordinates and monitors the plan. Under this, plan the major activities include treating the, pollution load from sewer systems of towns and, cities, setting up of Sewage treatment plants,, electric crematoria, low cost sanitation facilities,, , Control measures for preventing water, pollution, While the foremost necessity is prevention, setting up effluent treatment plants and treating, waste through these can reduce the pollution, load in the recipient water. The treated effluent, can be reused for either gardening or cooling, purposes wherever possible. A few years ago a, new technology called the Root Zone Process, has been developed by Thermax. This system, involves running contaminated water through, the root zones of specially designed reed beds., The reeds, which are essentially wetland plants, have the capacity to absorb oxygen from the, surrounding air through their stomatal openings., The oxygen is pushed through the porous stem, of the reeds into the hollow roots where it enters the root zone and creates conditions suitable for the growth of numerous bacteria and, fungi. These micro-organisms oxidize impurities, in the wastewaters, so that the water which finally comes out is clean., , Water Pollution, , Environmental Studies for Undergraduate Courses, , 130, , Chapter5.p65, , riverfront development, afforestation and solid, waste management., , 130, , 4/9/2004, 5:09 PM
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5.2.3 Soil Pollution, Introduction: We can no more manufacture a, soil with a tank of chemicals than we can invent, a rain forest or produce a single bird. We may, enhance the soil by helping its processes along,, but we can never recreate what we destroy. The, soil is a resource for which there is no substitute. (Environmental historian Donald Worster, reminds us that fertilizers are not a substitute, for fertile soil)., Soil is a thin covering over the land consisting of, a mixture of minerals, organic material, living, organisms, air and water that together support, the growth of plant life. Several factors contribute to the formation of soil from the parent, material. This includes mechanical weathering, of rocks due to temperature changes and abrasion, wind, moving water, glaciers, chemical, weathering activities and lichens. Climate and, time are also important in the development of, soils. Extremely dry or cold climates develop soils, very slowly while humid and warm climates develop them more rapidly. Under ideal climatic, conditions soft parent material may develop into, a centimeter of soil within 15 years. Under poor, climatic conditions a hard parent material may, require hundreds of years to develop into soil., Mature soils are arranged in a series of zones, called soil horizons. Each horizon has a distinct, texture and composition that varies with different types of soils. A cross sectional view of the, horizons in a soil is called a soil profile., The top layer or the surface litter layer called, the O horizon consists mostly of freshly fallen, and partially decomposed leaves, twigs, animal, waste, fungi and other organic materials. Normally it is brown or black., The uppermost layer of the soil called the A, horizon consists of partially decomposed organic, matter (humus) and some inorganic mineral, particles. It is usually darker and looser than the, , deeper layers. The roots of most plants are found, in these two upper layers. As long as these layers are anchored by vegetation soil stores water and releases it in a trickle throughout the, year instead of in a force like a flood. These two, top layers also contain a large amount of bacteria, fungi, earthworms and other small insects, that form complex food webs in the soil that, help recycle soil nutrients and contribute to soil, fertility., The B horizon often called the subsoil contains, less organic material and fewer organisms than, the A horizon. The area below the subsoil is, called the C horizon and consists of weathered, parent material. This parent material does not, contain any organic materials. The chemical, composition of the C-horizon helps to determine, the pH of the soil and also influences the soil’s, rate of water absorption and retention., Soils vary in their content of clay (very fine particles), silt (fine particles), sand (medium size, particles) and gravel (coarse to very coarse particles). The relative amounts of the different sizes, and types of mineral particles determine soil, texture. Soils with approximately equal mixtures, of clay, sand, silt and humus are called loams., , Causes of soil degradation, Erosion, Soil erosion can be defined as the movement of, surface litter and topsoil from one place to another. While erosion is a natural process often, caused by wind and flowing water it is greatly, accelerated by human activities such as farming, construction, overgrazing by livestock, burning of grass cover and deforestation., Loss of the topsoil makes a soil less fertile and, reduces its water holding capacity. The topsoil,, which is washed away, also contributes to water pollution clogging lakes, increasing turbidity, of the water and also leads to loss of aquatic, , Pollution, , Chapter5.p65, , 131, , 131, , 4/9/2004, 5:09 PM
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life. For one inch of topsoil to be formed it normally requires 200-1000 years depending upon, the climate and soil type. Thus if the topsoil, erodes faster than it is formed the soil becomes, a non-renewable resource., Thus it is essential that proper soil conservation, measures are used to minimize the loss of top, soil. There are several techniques that can protect soil from erosion. Today both water and, soil are conserved through integrated treatment, methods. Some of the most commonly employed methods include the two types of treatment that are generally used., •, , Area treatment which involves treating the, land, , •, , Drainage line treatment which involves, treating the natural water courses (nalas), , Continuous contour trenches can be used to, enhance infiltration of water reduce the runoff and check soil erosion. These are actually, shallow trenches dug across the slope of the, land and along the contour lines basically for, , the purpose of soil and water conservation. They, are most effective on gentle slopes and in areas, of low to medium rainfall. These bunds are stabilized by fast growing tree species and grasses., In areas of steep slopes where the bunds are, not possible, continuous contour benches (CCBs), made of stones are used for the same purpose., Gradonies can also be used to convert wastelands into agricultural lands. In this narrow, trenches with bunds on the downstream side, are built along contours in the upper reaches of, the catchment to collect run-off and to conserve, moisture from the trees or tree crops. The area, between the two bunds is use for cultivation of, crops after development of fertile soil cover., Some of the ways in which this can be achieved, are:, Live check dams which barriers created by, planting grass, shrubs and trees across the gullies can be used for this purpose., A bund constructed out of stones across the, stream can also be used for conserving soil and, water., , Area Treatment, Purpose, , Treatment Measure, , Effect, , Reduces the impact of, rain drops on the soil, , Develop vegetative cover on the, non arable land, , Minimum disturbance and, displacement of soil particles, , Infiltration of water, where it falls, , Apply water infiltration measures on, the area, , In situ soil and moisture conservation, , Minimum surface run off, , Store surplus rain water by constructing, bunds, ponds in the area, , Increased soil moisture in the area,, facilitate ground water recharge, , Ridge to valley sequencing Treat the upper catchment first and then Economically viable, less risk, proceed towards the outlet, of damage and longer life of, structures of the lower catchments, , Environmental Studies for Undergraduate Courses, , 132, , Chapter5.p65, , 132, , 4/9/2004, 5:09 PM
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Drainage line treatment, Purpose, , Treatment measure, , Effect, , Stop further deepening, of gullies and retain, sediment run-off, , Plug the gullies at formation, , Stops erosion, recharges, groundwater at the, upper level., , Reduce run-off velocity,, pass cleaner water to the, downstream side, , Crate temporary barriers in nalas, , Delayed flow and, increased groundwater, recharge, , Minimum sedimentation, in the storage basins, , Use various methods to treat the catchments, , Low construction cost, , Use local material and skills for constructing, the structures, , An Earthen checkbund is constructed out of, local soil across the stream to check soil erosion, and flow of water., A Gabion structure is a bund constructed of, stone and wrapped in galvanized chainlink., A Gabion structure with ferrocement impervious barrier has a one inch thick impervious, wall of ferrocement at the center of the structure which goes below the ground level upto, the hard strata. This ferrocement partition supported by the gabion portion is able to retain, the water and withstand the force of the runoff, water., An Underground bandhara is an underground structure across a nalla bed to function as a barrier to check the ground water, movement., Excess use of fertilizers: Approximately 25, percent of the world’s crop yield is estimated to, be directly attributed to the use of chemical fertilizers. The use of chemical fertilizes has increased significantly over the last few decades, , Structures are locally, maintained, , and is expected to rise even higher. Fertilizers, are very valuable as they replace the soil nutrients used up by plants. The three primary soil, nutrients often in short supply are potassium,, phosphorus and nitrogen compounds. These are, commonly referred to as macronutrients. Certain other elements like boron, zinc and manganese are necessary in extremely small amounts, and are known as micronutrients. When crops, are harvested a large amount of macronutrients, and a small amount of micronutrients are removed with the crops. If the same crop is grown, again depleted levels of thee nutrients can result in decreased yields. These necessary nutrients can be returned to the soil through the, application of fertilizers. In addition to fertilizers, a large amount of pesticides (chemicals used to, kill or control populations of unwanted fungi,, animals or plants often called pests) are also used, to ensure a good yield. Pesticides can be subdivided into several categories based on the kinds, of organisms they are used to control. Insecticides are used to control insect populations while, fungicides are used to control unwanted fungal, growth. Mice and rats are killed by rodenticides, while plant pests are controlled by herbicides., , Pollution, , Chapter5.p65, , 133, , 133, , 4/9/2004, 5:09 PM
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Problems with pesticide use, Pesticides not only kill the pests but also a large, variety of living things including humans. They, may be persistent or non-persistent. Persistent, pesticides once applied are effective for a long, time. However as they do not break down easily they tend to accumulate in the soil and in the, bodies of animals in the food chain., For example, DDT which was one of the first, synthetic organic insecticide to be used was, thought to be the perfect insecticide. During the, first ten years of its use (1942-1952) DDT is estimated to have saved about five million lives, primarily because of its use to control disease, carrying mosquitoes. However after a period of, use many mosquitoes and insects became tolerant of DDT, thus making it lose its effectiveness. DDT in temperate regions of the world, has a half life (the amount of time required for, half of the chemical to decompose) of 10 to 15, years. This means that if 100 kilograms of DDT, were to be sprayed over an area, 50 kilograms, would still be present in the area 10 to 15 years, later. The half-life of DDT varies according to, the soil type, temperature, kind of soil organisms present and other factors. In tropical parts, of the world the half life may be as short as six, months. The use of DDT has been banned in, some countries. India still however permits the, use of DDT though for purposes of mosquito, control only. Persistent pesticides become attached to small soil particles which are easily, moved by wind and water to different parts thus, affecting soils elsewhere. Persistent pesticides, may also accumulate in the bodies of animals,, and over a period of time increase in concentration if the animal is unable to flush them out, of its system thus leading to the phenomenon, called bioaccumulation. When an affected animal is eaten by another carnivore these pesticides are further concentrated in the body of, the carnivore. This phenomenon of acquiring, increasing levels of a substance in the bodies of, higher trophic level organisms is known as, biomagnification. This process especially in the, , Other problems associated with insecticides is, the ability of insect populations to become resistant to them thus rendering them useless in a, couple of generations. Most pesticides kill beneficial as well as pest species. They kill the predator as well as the parasitic insects that control, the pests. Thus the pest species increase rapidly, following the use of a pesticide as there are no, natural checks to their population growth. The, short term and the long-term health effects to, the persons using the pesticide and the public, that consumes the food grown by using the, pesticides are also major concerns. Exposure to, small quantities of pesticides over several years, can cause mutations, produce cancers, etc., Thus the question that comes to mind is that if, pesticides have so many drawbacks then why, are they used so extensively and what are the, substitutes for them? There are three main reasons for the use of pesticides. Firstly the use of, pesticides in the short term has increased the, amount of food that can be grown in many parts, of the world as the damage by pests is decreased. The second reason for its extensive use, is base on an economic consideration. The increased yields more than compensates the, farmer for cost of pesticides. Thirdly current, health problems especially in developing countries due to mosquitoes are impossible to control without insecticides., However more and more farmers are increasingly opting to replace chemical fertilizers and, use different methods of controlling pests without affecting their yield. Thus several different, approaches that have slightly varying and overlapping goals have been developed. Alternative, agriculture is the broadest term that is used that, includes all non-traditional agricultural methods, Environmental Studies for Undergraduate Courses, , 134, , Chapter5.p65, , case of insecticides like DDT have been proved, to be disastrous. DDT is a well known case of, biomagnification in ecosystems. DDT interferes, with the production of normal eggshells in birds, making them fragile., , 134, , 4/9/2004, 5:09 PM
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and encompasses sustainable agriculture, organic agriculture, alternative uses of traditional, crops, alternative methods for raising crops, etc., Sustainable agriculture advocates the use of, methods to produce adequate safe food in an, economically viable manner while maintaining, the state of the ecosystem. Organic agriculture, advocates avoiding the use of chemical fertilizers and pesticides. A wide variety of techniques, can be used to reduce this negative impact of, agriculture. Leaving crop residue on the soil and, incorporating it into the soil reduces erosion and, increase soil organic matter. Introduction of organic matter into the soil also makes compaction less likely. Crop rotation is an effective way, to enhance soil fertility, reduce erosion and control pests. There have been arguments both for, and against organic farming. Critics argue that, organic farming cannot produce the amount of, food required for today’s population and it is, economically viable only in certain conditions., However supporters for organic farming feel, that of the hidden costs of soil erosion and pollution are taken into account it is a viable approach. Besides organic farmers do not have to, spend on fertilizers and pesticides and also get, a premium price for their products thus making, it financially viable for them., Another way to reduce these impacts is through, the use of integrated pest management. This is, a technique that uses a complete understanding of all ecological aspects of a crop and the, particular pests to which it is susceptible to establish pest control strategies that uses no or, few pesticides. IPM promotes the use of, biopesticides. Biopesticides are derived from, three sources: microbial, botanical and biochemical. Microbial pesticides are micro-organisms such as bacteria, fungus, virus or protozoa, that fight pests through a variety of ways. They, produce toxins specific to the pests and produce, diseases in them. Biochemical pesticides contain, several chemicals that affect the reproductive, and digestive mechanisms of the pests. The most, , commonly used biopesticides are Bacillus, thuringiensis (Bt), neem (Azadirachta indica) and, trichogramma. Although they are available in, the market they are yet to become market, favourites., , Excess salts and water, Irrigated lands can produce crop yields much, higher than those that only use rainwater. However this has its own set of ill effects. Irrigation, water contains dissolved salts and in dry climates, much of the water in the saline solution evaporates leaving its salts such as sodium chloride in, the topsoil. The accumulation of these salts is, called salinization, which can stunt plant growth,, lower yields and eventually kill the crop and render the land useless for agriculture. These salts, can be flushed out of the soil by using more, water. This practice however increases the cost, of crop production and also wastes enormous, amounts of water. Flushing salts can also make, the downstream irrigation water saltier., Another problem with irrigation is water logging. This occurs when large amounts of water, is used to leach the salts deeper into the soil., However if the drainage is poor this water accumulates underground gradually raising the, water table. The roots of the plants then get, enveloped in this saline water and eventually, die., Thus in the long run it is better for us to adopt, sustainable farming practices so as to prevent, the degradation of soil., , 5.2.4 Marine Pollution, Marine pollution can be defined as the introduction of substances to the marine environment directly or indirectly by man resulting in, adverse effects such as hazards to human health,, obstruction of marine activities and lowering the, quality of sea water. While the causes of ma-, , Pollution, , Chapter5.p65, , 135, , 135, , 4/9/2004, 5:09 PM
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rine pollution may be similar to that of general, water pollution there are some very specific, causes that pollute marine waters., •, , The most obvious inputs of waste is through, pipes directly discharging wastes into the, sea. Very often municipal waste and sewage from residences and hotels in coastal, towns are directly discharged into the sea., , •, , Pesticides and fertilizers from agriculture, which are washed off the land by rain, enter water courses and eventually reach the, sea., , •, , Ships carry many toxic substances such as, oil, liquefied natural gas, pesticides, industrial chemicals, etc. in huge quantities sometimes to the capacity of 350,000 tonnes., Ship accidents and accidental spillages at, sea therefore can be very damaging to the, marine environment. Shipping channels in, estuaries and at the entrances to ports often require frequent dredging to keep them, open. This dredged material that may contain heavy metals and other contaminants, are often dumped out to sea., , •, , Offshore oil exploration and extraction also, pollute the seawater to a large extent., , Petroleum and oils washed off from the, roads normally enter the sewage system but, stormwater overflows carry these materials, into rivers and eventually into the seas., Environmental Studies for Undergraduate Courses, , 136, , Chapter5.p65, , •, , 136, , 4/9/2004, 5:09 PM
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Pollution due to organic wastes, The amount of oxygen dissolved in the water is, vital for the plants and animals living in it., Wastes, which directly or indirectly affect the, oxygen concentration, play an important role in, determining the quality of the water. Normally, the greatest volume of waste discharged to, watercourses, estuaries and the sea is sewage,, which is primarily organic in nature and is degraded by bacterial activity. Using the oxygen, present in the water these wastes are broken, down into stable inorganic compounds. However as a result of this bacterial activity the oxygen concentration in the water is reduced. When, the oxygen concentration falls below 1.5 mg/, lit, the rate of aerobic oxidation is reduced and, their place is taken over by the anaerobic bacteria that can oxidize the organic molecules without the use of oxygen. This results in end, products such as hydrogen sulphide, ammonia, and methane, which are toxic to many organisms. This process results in the formation of an, anoxic zone which is low in its oxygen content, from which most life disappears except for, anaerobic bacteria, fungi, yeasts and some protozoa. This makes the water foul smelling., Control measures: One way of reducing the, pollution load on marine waters is through the, introduction of sewage treatment plants. This, will reduce the biological oxygen demand (BOD), of the final product before it is discharged to, the receiving waters., Various stages of treatment such as primary,, secondary or advanced can be used depending, on the quality of the effluent that is required to, be treated., Primary treatment: These treatment plants use, physical processes such as screening and sedimentation to remove pollutants that will settle,, float or, that are too large to pass through simple, screening devices. This includes, stones, sticks,, rags, and all such material that can clog pipes., A screen consists of parallel bars spaced 2 to, 7cms apart followed by a wire mesh with smaller, , openings. One way of avoiding the problem of, disposal of materials collected on the screens is, to use a device called a comminuter which grinds, the coarse material into small pieces that can, then be left in the waste water. After screening, the wastewater passes into a grit chamber. The, detention time is chosen to be long enough to, allow lighter, organic material to settle. From, the grit chamber the sewage passes into a primary settling tank (also called as sedimentation, tank) where the flow speed is reduced sufficiently to allow most of the suspended solids to, settle out by gravity. If the waste is to undergo, only primary treatment it is then chlorinated to, destroy bacteria and control odours after which, the effluent is released. Primary treatment normally removes about 35 percent of the BOD and, 60 percent of the suspended solids., Secondary treatment: The main objective of, secondary treatment is to remove most of the, BOD. There are three commonly used approaches: trickling filters, activated sludge process and oxidation ponds. Secondary treatment, can remove at least 85 percent of the BOD., A trickling filter consists of a rotating distribution arm that sprays liquid wastewater over a, circular bed of ‘fist size’ rocks or other coarse, materials. The spaces between the rocks allow, air to circulate easily so that aerobic conditions, can be maintained. The individual rocks in the, bed are covered with a layer of slime, which, consists of bacteria, fungi, algae, etc. which, degrade the waste trickling through the bed., This slime periodically slides off individual rocks, and is collected at the bottom of the filter along, with the treated wastewater and is then passed, on to the secondary settling tank where it is removed., In the activated sludge process the sewage is, pumped into a large tank and mixed for several, hours with bacteria rich sludge and air bubbles, to facilitate degradation by micro-organisms., The water then goes into a sedimentation tank, , Pollution, , Chapter5.p65, , 137, , 137, , 4/9/2004, 5:09 PM
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where most of the microorganisms settle out as, sludge. This sludge is then broken down in an, anaerobic digester where methane-forming, bacteria slowly convert the organic matter into, carbon dioxide, methane and other stable end, products. The gas produced in the digester is, 60 percent methane, which is a valuable fuel, and can be put to many uses within the treatment plant itself. The digested sludge, which is, still liquid, is normally pumped out onto sludge, drying beds where evaporation and seepage, remove the water. This dried sludge is potentially a good source of manure. Activated sludge, tanks use less land area than trickling filters with, equivalent performance. They are also less expensive to construct than trickling filters and, have fewer problems with flies and odour and, can also achieve higher rates of BOD removal., Thus although the operating costs are a little, higher due to the expenses incurred on energy, for running pumps and blowers they are preferred over trickling filters., , Oxidation ponds are large shallow ponds approximately 1 to 2 metres deep where raw or, partially treated sewage is decomposed by microorganisms. They are easy to build and manage and accommodate large fluctuations in flow, and can provide treatment at a much lower cost., They however require a large amount of land, and hence can be used where land is not a limitation., Advanced sewage treatment: This involves a, series of chemical and physical process that removes specific pollutants left in the water after, primary and secondary treatment. Sewage treatment plant effluents contain nitrates and phosphates in large amounts. These contribute to, eutrophication. Thus advanced treatment plants, are designed to specifically remove these contaminants. Advanced treatment plants are very, expensive to build and operate and hence are, rarely used., , Tanker operations, Half the world production of crude oil which is, close to three billion tones a year is transported, by sea. After a tanker has unloaded its cargo of, oil it has to take on seawater as ballast for the, return journey. This ballast water is stored in the, cargo compartments that previously contained, the oil. During the unloading of the cargo a certain amount of oil remains clinging to the walls, of the container and this may amount to 800, tonnes in a 200,000 tonne tanker. The ballast, water thus becomes contaminated with this oil., When a fresh cargo of oil is to be loaded, these, compartments are cleaned with water, which, discharges the dirty ballast along with the oil, into the sea. Two techniques have substantially, reduced this oil pollution. In the load-on-top, system, the compartments are cleaned by high, pressure jets of water. The oily water is retained, in the compartment until the oil floats to the, top. The water underneath that contains only a, little oil is then discharged into the sea and the, oil is transferred to a slop tank. At the loading, terminal, fresh oil is loaded on top of the oil in, the tank and hence the name of the technique., In the second method called ‘crude oil washing’, the clingage is removed by jets of crude oil, while the cargo is being unloaded. Some modern tankers have segregated ballast where the, ballast water does not come in contact with the, oil. Thus with the introduction of these new, methods of deballasting, the amount of oil entering the sea has been considerably reduced., , Dry docking, All ships need periodic dry docking for servicing, repairs, cleaning the hull, etc. During this, period when the cargo compartments are to, Environmental Studies for Undergraduate Courses, , 138, , Chapter5.p65, , Pollution due to oil: Oil pollution of the sea, normally attracts the greatest attention because, of its visibility. There are several sources though, which the oil can reach the sea., , 138, , 4/9/2004, 5:09 PM
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completely emptied, residual oil finds its way into, the sea., , Bilge and fuel oils, As ballast tanks take up valuable space, additional ballast is sometimes carried in empty fuel, tanks. While being pumped overboard it carries, oil into the sea. Individually the quantity of oil, released may be small but it becomes a considerable amount when all the shipping operations, are taken into consideration., , Tanker accidents, A large number of oil tanker accidents happen, every year. Sometimes this can result in major, disasters such as that of the Exxon Valdez described in the section on water pollution., , Offshore oil production, Oil that is extracted from the seabed contains, some water. Even after it is passed through oil, separators the water that is discharged contains, some oil, which adds to marine pollution. Drilling muds which are pumped down oil wells, when it is being drilled normally contain 70 to, 80 percent of oil. They are dumped on the seabed beneath the platform thus heavily contaminating the water. Uncontrolled release of oil, from the wells can be catastrophic events resulting in oil pollution., Control measures for oil pollution: Cleaning, oil from surface waters and contaminated, beaches is a time consuming labour intensive, process. The natural process of emulsification, of oil in the water can be accelerated through, the use of chemical dispersants which can be, sprayed on the oil. A variety of slick-lickers in, which a continuous belt of absorbent material, dips through the oil slick and is passed through, rollers to extract the oil have been designed., Rocks, harbour walls can be cleaned with high-, , pressure steam or dispersants after which the, surface must be hosed down., Effects of marine pollution: Apart from causing eutrophication a large amount of organic, wastes can also result in the development of, red tides. These are phytoplankton blooms of, such intensity that the area is discolored. Many, important commercially important marine species are also killed due to clogging of gills or, other structures., When liquid oil is spilled on the sea it spreads, over the surface of the water to form a thin film, called an oil slick. The rate of spreading and the, thickness of the film depends on the sea temperature and the nature of the oil., Oil slicks damage marine life to a large extent., Salt marshes, mangrove swamps are likely to, trap oil and the plants, which form the basis for, these ecosystems thus suffer. For salt marsh, plants, oil slicks can affect the flowering, fruiting and germination., If liquid oil contaminates a bird’s plumage its, water repellent properties are lost. Water thus, penetrates the plumage and displaces the air, trapped between the feathers and the skin. This, air layer is necessary as it provides buoyancy and, thermal insulation. With this loss the plumage, becomes water logged and the birds may sink, and drown. Even if this does not happen loss of, thermal insulation results in exhaustion of food, reserves in an attempt to maintain body temperature often followed by death. Birds often, clean their plumage by preening and in the process consume oil which depending on its toxicity can lead to intestinal, renal or liver failure., Drill cuttings dumped on the seabed create anoxic conditions and result in the production of, toxic sulphides in the bottom sediment thus, eliminating the benthic fauna., , Pollution, , Chapter5.p65, , 139, , 139, , 4/9/2004, 5:09 PM
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Fish and shellfish production facilities can also, be affected by oil slicks. The most important, commercial damage can however also come, from tainting which imparts an unpleasant, flavour to fish and seafood and is detectable at, extremely low levels of contamination. This reduces the market value of seafood., , 5.2.5 Noise Pollution, Noise may not seem as harmful as the contamination of air or water but it is a pollution problem that affects human health and can, contribute to a general deterioration of environmental quality., Noise is undesirable and unwanted sound. Not, all sound is noise. What may be considered as, music to one person may be noise to another. It, is not a substance that can accumulate in the, environment like most other pollutants. Sound, is measured in a unit called the ‘Decibel’., , The differences between sound and noise is often subjective and a matter of personal opinion. There are however some very harmful, effects caused by exposure to high sound levels. These effects can range in severity from, being extremely annoying to being extremely, painful and hazardous., , Decibel levels of common sounds, , Effects of noise pollution on physical health, , dB, , Environmental Condition, , 0, , Threshold of hearing, , 10, , Rustle of leaves, , 20, , Broadcasting studio, , 30, , Bedroom at night, , 40, , Library, , 50, , Quiet office, , 60, , Conversational speech (at 1m), , 70, , Average radio, , 74, , Light traffic noise, , 90, , Subway train, , 100, , Symphony orchestra, , 110, , Rock band, , 120, , Aircraft takeoff, , 146, , Threshold of pain, , The most direct harmful effect of excessive noise, is physical damage to the ear and the temporary or permanent hearing loss often called a, temporary threshold shift (TTS). People suffering from this condition are unable to detect, weak sounds. However hearing ability is usually, recovered within a month of exposure. In, Maharashtra people living in close vicinity of, Ganesh mandals that play blaring music for ten, days of the Ganesh festival are usually known, to suffer from this phenomenon. Permanent, loss, usually called noise induced permanent, threshold shift (NIPTS) represents a loss of hearing ability from which there is no recovery., Below a sound level of 80 dBA haring loss does, not occur at all. However temporary effects are, noticed at sound levels between 80 and 130, dBA. About 50 percent of the people exposed, Environmental Studies for Undergraduate Courses, , 140, , Chapter5.p65, , There are several sources of noise pollution that, contribute to both indoor and outdoor noise, pollution. Noise emanating from factories, vehicles, playing of loudspeakers during various, festivals can contribute to outdoor noise pollution while loudly played radio or music systems,, and other electronic gadgets can contribute to, indoor noise pollution. A study conducted by, researchers from the New Delhi based National, Physical Laboratory show that noise generated, by firecrackers (presently available in the market) is much higher than the prescribed levels., The permitted noise level is 125 decibels, as per, the Environment (Protection) (second amendment) Rules, 1999., , 140, , 4/9/2004, 5:09 PM
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to 95 dBA sound levels at work will develop, NIPTS and most people exposed to more than, 105 dBA will experience permanent hearing loss, to some degree. A sound level of 150 dBA or, more can physically rupture the human eardrum., The degree of hearing loss depends on the duration as well as the intensity of the noise. For, example, 1hour of exposure to a 100 dBA sound, level can produce a TTS that may last for about, one day. However in factories with noisy machinery workers are subjected to high sound, levels for several hours a day. Exposure to 95, dBA for 8 hours everyday for over a period of, 10 years may cause about 15 dBA of NIPTS. In, addition to hearing losses excessive sound levels can cause harmful effects on the circulatory, system by raising blood pressure and altering, pulse rates., , Effects of noise pollution on mental health:, Noise can also cause emotional or psychological effects such as irritability, anxiety and stress., Lack of concentration and mental fatigue are, significant health effects of noise. It has been, observed that the performance of school children is poor in comprehension tasks when, schools are situated in busy areas of a city and, suffer from noise pollution., As noise interferes with normal auditory communication, it may mask auditory warning signals and hence increases the rate of accidents, especially in industries. It can also lead to lowered worker efficiency and productivity and, higher accident rates on the job., Thus noise is just more than a mere nuisance or, annoyance. It definitely affects the quality of life., It is thus important to ensure mitigation or control of noise pollution., , Permitted noise levels, Ambient Noise Levels dB, , Zone, , Day-time, , Night-time, , Silent Zone, , 50, , 40, , Residential Zone, , 55, , 45, , Commercial Zone, , 65, , 55, , Industrial Zone, , 70, , 70, , A standard safe time limit has been set for exposure to various noise levels. Beyond this ‘safe’, time continuing exposure over a period of a year, will lead to hearing loss., , Duration, , dBA, , 8 hours, , 90, , 4 hours, , 93, , 2 hours, , 96, , 1 hour, , 99, , 30 minutes, , 102, , 15 minutes, , 105, , 7 minutes, , 108, , 4 minutes, , 111, , 2 minutes, , 114, , 1 minute, , 117, , 30 seconds, , 120, , Instantaneous rupture of membrane, , 150, , Noise Control techniques, There are four fundamental ways in which noise, can be controlled: Reduce noise at the source,, block the path of noise, increase the path length, and protect the recipient. In general, the best, control method is to reduce noise levels at the, source., , Pollution, , Chapter5.p65, , 141, , 141, , 4/9/2004, 5:09 PM
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Source reduction can be done by effectively, muffling vehicles and machinery to reduce the, noise. In industries noise reduction can be done, by using rigid sealed enclosures around machinery lined with acoustic absorbing material. Isolating machines and their enclosures from the, floor using special spring mounts or absorbent, mounts and pads and using flexible couplings, for interior pipelines also contribute to reducing, noise pollution at the source., However one of the best methods of noise, source reduction is regular and thorough maintenance of operating machinery. Noise levels at, construction sites can be controlled using proper, construction planning and scheduling techniques. Locating noisy air compressors and other, equipment away from the site boundary along, with creation of temporary barriers to physically, block the noise can help contribute to reducing, noise pollution. Most of the vehicular noise, comes from movement of the vehicle tires on, the pavement and wind resistance. However, poorly maintained vehicles can add to the noise, levels. Traffic volume and speed also have significant effects on the overall sound. For example, doubling the speed increases the sound levels, by about 9 dBA and doubling the traffic volume, (number of vehicles per hour) increases sound, levels by about 3 dBA. A smooth flow of traffic, also causes less noise than does a stop-and-go, traffic pattern. Proper highway planning and, design are essential for controlling traffic noise., Establishing lower speed limits for highways that, pass through residential areas, limiting traffic, volume and providing alternative routes for truck, traffic are effective noise control measures. The, path of traffic noise can also be blocked by construction of vertical barriers alongside the highway. Planting of trees around houses can also, act as effective noise barriers. In industries different types of absorptive material can be used, to control interior noise. Highly absorptive interior finish material for walls, ceilings and floors, can decrease indoor noise levels significantly., Sound levels drop significantly with increasing, , 5.2.6 Thermal Pollution, Sources: The discharge of warm water into a, river is usually called a thermal pollution. It, occurs when an industry removes water from a, source, uses the water for cooling purposes and, then returns the heated water to its source., Power plants heat water to convert it into steam,, to drive the turbines that generate electricity., For efficient functioning of the steam turbines,, the steam is condensed into water after it leaves, the turbines. This condensation is done by taking water from a water body to absorb the heat., This heated water, which is at least 15oC higher, than the normal is discharged back into the, water body., Effects: The warmer temperature decreases the, solubility of oxygen and increases the metabolism of fish. This changes the ecological balance, of the river. Within certain limits thermal additions can promote the growth of certain fish, and the fish catch may be high in the vicinity of, a power plant. However sudden changes in temperature caused by periodic plant shutdowns, both planned and unintentional can change result in death of these fish that are acclimatized, to living in warmer waters., Tropical marine animals are generally unable to, withstand a temperature increase of 2 to 30C, Environmental Studies for Undergraduate Courses, , 142, , Chapter5.p65, , distance from the noise source. Increasing the, path length between the source and the recipient offers a passive means of control. Municipal land-use ordinances pertaining to the, location of airports make use of the attenuating effect of distance on sound levels. Use of, earplugs and earmuffs can protect individuals, effectively from excessive noise levels. Specially, designed earmuffs can reduce the sound level, reaching the eardrum by as much as 40 dBA., However very often workers tend not to wear, them on a regular basis despite company requirements for their use., , 142, , 4/9/2004, 5:09 PM
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and most sponges, mollusks and crustaceans are, eliminated at temperatures above 370C. This, results in a change in the diversity of fauna as, only those species that can live in warmer water survive., Control measures: Thermal pollution can be, controlled by passing the heated water through, a cooling pond or a cooling tower after it leaves, the condenser. The heat is dissipated into the, air and the water can then be discharged into, the river or pumped back to the plant for reuse, as cooling water. There are several ways in which, thermal pollution can be reduced. One method, is to construct a large shallow pond. Hot water, is pumped into one end of the pond and cooler, water is removed from the other end. The heat, gets dissipated from the pond into the atmosphere. A second method is to use a cooling, tower. These structures take up less land area, than the ponds. Here most of the heat transfer, occurs through evaporation. Here warm waters, coming from the condenser is sprayed downward over vertical sheets or baffles where the, water flows in thin films. Cool air enters the, tower through the water inlet that encircles the, base of the tower and rises upwards causing, evaporative cooling. A natural draft is maintained because of the density difference between the cool air outside and the warmer air, inside the tower. The waste heat is dissipated, into the atmosphere about 100 m above the, base of the tower. The cooled water is collected, at the floor of the tower and recycled back to, the power plant condensers. The disadvantage, in both these methods is however that large, amounts of water are lost by evaporation., , 5.2.7 Nuclear Hazards, Nuclear energy can be both beneficial and harmful depending on the way in which it is used., We routinely use X-rays to examine bones for, fractures, treat cancer with radiation and diagnose diseases with the help of radioactive iso-, , topes. Approximately 17 % of the electrical, energy generated in the world comes from, nuclear power plants. However on the other, hand it is impossible to forget the destruction, that nuclear bombs caused the cities of, Hiroshima and Nagasaki. The radioactive wastes, from nuclear energy have caused serious environmental damage., Nuclear fission is the splitting of the nucleus of, the atom. The resulting energy can be used for, a variety of purposes. The first controlled fission, of an atom was carried out in Germany in 1938., However the United States was the first country to develop an atomic bomb which was subsequently dropped on the Japanese cities of, Hiroshima and Nagasaki. The world’s first electricity generating reactor was constructed in the, United States in 1951 and the Soviet Union built, its first reactor in 1954. In December 1953, President Dwight D. Eisenhower in his ‘Atoms for, Peace’ speech made the following prediction:, ‘Nuclear reactors will produce electricity so, cheaply that it will not be necessary to meter it., The users will pay a fee and use as much electricity as they want. Atoms will provide a safe,, clean and dependable source of electricity.’, Today however though nuclear power is being, used as a reliable source of electricity the above, statement sounds highly optimistic. Several serious accidents have caused worldwide concern, about safety and disposal of radioactive wastes., In order to appreciate the consequences of using nuclear fuels to generate energy it is important to understand how the fuel is processed., Low-grade uranium ore, which contains 0.2, percent uranium by weight, is obtained by surface or underground mining. After it is mined, the ore goes through a milling process where it, is crushed and treated with a solvent to concentrate the uranium and produces yellow cake, a material containing 70 to 90 percent uranium, oxide. Naturally occurring uranium contains only, 0.7 percent of fissionable U-235, which is not, , Pollution, , Chapter5.p65, , 143, , 143, , 4/9/2004, 5:09 PM
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high enough for most types of reactors. Hence, it is necessary to increase the amount of U-235, by enrichment though it is a difficult and expensive process. The enrichment process increases the U-235 content from 0.7 to 3 percent., Fuel fabrication then converts the enriched material into a powder, which is then compacted, into pellets. These pellets are sealed in metal, fuel rods about 4 meters in length which is then, loaded into the reactor. As fission occurs the, concentration of U-235 atoms decreases. After, about three years, a fuel rod does not have, enough radioactive material to sustain a chain, reaction and hence the spent fuel rods must be, replaced by new ones. The spent rods are however still very radioactive containing about one, percent U-235 and one percent plutonium., These rods are a major source of radioactive, waste material produced by a nuclear reactor., Initially it was thought that spent fuel rods could, be reprocessed to not only provide new fuel but, also to reduce the amount of nuclear waste., However the cost of producing fuel rods by reprocessing was found to be greater than the, cost of producing fuel rods from ore. Presently, India does operate reprocessing plants to reprocess spent fuel as an alternative to storing them, as nuclear waste. At each step in the cycle there, is a danger of exposure and poses several health, and environmental concerns., Although nuclear power has significant benefits, an incident which changed people’s attitudes, towards nuclear power plants was the, Chernobyl disaster that occurred in 1986., Chernobyl is a small city in Ukraine near the, border with Belarus north of Kiev. At 1.00 am, April 25, 1986 a test to measure the amount of, electricity that the still spinning turbine would, produce if steam were shut off was being conducted at the Chernobyl Nuclear Power Station4. This was important information since the, emergency core cooling system required energy, for its operation and the coasting turbine could, provide some of that energy until another source, , At 1.00am, the operators shut off most of the, emergency warning signals and turned on all, the eight pumps to provide adequate cooling, for the reactor following the completion of the, test. Just as the final stages for the test were, beginning a signal indicated excessive reaction, in the reactor. In spite of the warning the operators blocked the automatic reactor shutdown, and began the test. As the test continued the, power output of the reactor rose beyond its, normal level and continued to rise. The operators activated the emergency system designed, to put the control rods back into the reactor, and stop the fission. But it was already too late., The core had already been deformed and the, rods would not fit properly thus the reaction, could not be stopped. In 4.5 seconds the energy level of the reactor increased two thousand times. The fuel rods ruptured the cooling, water turned into steam and a steam explosion, occurred. The lack of cooling water allowed the, reactor to explode. The explosion blew the 1000, metric ton concrete roof from the reactor and, the reactor caught fire. This resulted in the, world’s worst nuclear accident and it took ten, days to bring the runaway reaction under control., , Environmental Studies for Undergraduate Courses, , 144, , Chapter5.p65, , became available. The amount of steam being, produced was reduced by lowering the control, rods into the reactor. But the test was delayed, because of a demand for electricity and a new, shift of workers came on duty. The operators, failed to program the computer to maintain, power at 700 megawatts and the output, dropped to 30 megawatts. This presented an, immediate need to rapidly increase the power, and many of the control rods were withdrawn., Meanwhile an inert gas (xenon) had accumulated on the fuel rods. The gas absorbed the, neutrons and slowed the rate of power increase., In an attempt to obtain more power the operators withdrew all the control rods. This was a, second serious safety violation., , 144, , 4/9/2004, 5:09 PM
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There were of course immediate fatalities, but, the long-term consequences were devastating., 116,000 people were evacuated of which, 24,000 had received high doses of radiation., Even today many people suffer from illnesses, they feel are related to their exposure to the, fallout from Chernobyl. In 1996 ten years after, the accident it was clear that one of the longterm effects was the increased frequency of, thyroid cancer in children., The degree and the kind of damage from, nuclear accidents vary with the kind of radiation, the amount of radiation, the duration of, exposure and the types of cells irradiated. Radiation can also cause mutations which are, changes in the genetic makeup of the cells., Mutations can occur in the ovaries or the testes, leading to the formation of mutated eggs or, sperms which in turn can lead to abnormal offspring. Mutations can also occur in the tissues, of the body ad may manifest themselves as abnormal tissue growths known as cancer. Two, common cancers that are linked to increased, radiation exposure are leukemia and breast cancer., , 5.3 SOLID WASTE MANAGEEMNT:, CAUSES, EFFECTS AND CONTROL MEASURES OF URBAN AND INDUSTRIAL, WASTE, In ancient cities, food scraps and other wastes, were simply thrown into the unpaved streets, where they accumulated. Around 320 B.C. in, Athens, the first known law forbidding this practice was established and a system of waste removal began to evolve in several eastern, Mediterranean cities. Disposal methods were, very crude and often were just open pits outside the city walls. As populations increased,, efforts were made to transport the wastes out, further thus creating city dumps. Until recently, the disposal of municipal solid waste did not, attract much public attention. The favoured, , means of disposal was to dump solid wastes, outside the city or village limits., Around most towns and cities in India the approach roads are littered with multi-coloured, plastic bags and other garbage. Waste is also, burnt to reduce its volume. Modern methods, of disposal such as incineration and the development of sanitary landfills, etc. are now attempting to solve these problems. Lack of space, for dumping solid waste has become a serious, problem in several cities and towns all over the, world. Dumping and burning wastes is not an, acceptable practice today from either an environmental or a health perspective. Today disposal of solid waste should be part of an, integrated waste management plan. The, method of collection, processing, resource recovery and the final disposal should mesh with, one another to achieve a common objective., , Characteristics of municipal solid waste, Solid wastes are grouped or classified in several, different ways. These different classifications are, necessary to address the complex challenges of, solid waste management in an effective manner. The term municipal solid waste (MSW) is, generally used to describe most of the non-hazardous solid waste from a city, town or village, that requires routine collection and transport to, a processing or disposal site. Sources of MSW, include private homes, commercial establishments and institutions as well as industrial facilities. However MSW does not include wastes, from industrial processes, construction and, demolition debris, sewage sludge, mining wastes, or agricultural wastes., Municipal solid waste contains a wide variety of, materials. It can contain food waste such as vegetable and meat material, left over food, egg, shells, etc which is classified as wet garbage as, well as paper, plastic, tetrapacks, plastic cans,, newspaper, glass bottles, cardboard boxes, alu-, , Pollution, , Chapter5.p65, , 145, , 145, , 4/9/2004, 5:09 PM
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minum foil, metal items, wood pieces, etc. which, is classified as dry garbage., Control measures of urban and industrial, wastes: An integrated waste management, strategy includes three main components:, 1. Source reduction, 2. Recycling, 3. Disposal, Source reduction is one of the fundamental, ways to reduce waste. This can be done by using less material when making a product, reuse, of products on site, designing products or packaging to reduce their quantity. On an individual, level we can reduce the use of unnecessary items, while shopping, buy items with minimal packaging, avoid buying disposable items and also, avoid asking for plastic carry bags., Recycling is reusing some components of the, waste that may have some economic value., Recycling has readily visible benefits such as conservation of resources reduction in energy used, during manufacture and reducing pollution levels. Some materials such as aluminum and steel, can be recycled many times. Metal, paper, glass, and plastics are recyclable. Mining of new aluminum is expensive and hence recycled aluminum has a strong market and plays a significant, role in the aluminum industry. Paper recycling, can also help preserve forests as it takes about, 17 trees to make one ton of paper. Crushed, glass (cullet) reduces the energy required to, manufacture new glass by 50 percent. Cullet, lowers the temperature requirement of the, glassmaking process thus conserving energy and, reducing air pollution. However even if recycling, is a viable alternative, it presents several problems., The problems associated with recycling are either technical or economical. Plastics are difficult to recycle because of the different types of, polymer resins used in their production. Since, each type has its own chemical makeup differ-, , Disposal of solid waste is done most commonly, through a sanitary landfill or through incineration. A modern sanitary landfill is a depression, in an impermeable soil layer that is lined with, an impermeable membrane. The three key characteristics of a municipal sanitary landfill that, distinguish it from an open dump are:, •, , Solid waste is placed in a suitably selected, and prepared landfill site in a carefully prescribed manner., , •, , The waste material is spread out and compacted with appropriate heavy machinery., , •, , The waste is covered each day with a layer, of compacted soil., , The problem with older landfills are associated, with groundwater pollution. Pollutants seeping, out from the bottom of a sanitary landfill, (leachates) very often percolate down to the, groundwater aquifer no matter how thick the, underlying soil layer. Today it is essential to have, suitable bottom liners and leachate collection, systems along with the installation of monitoring systems to detect groundwater pollution., The organic material in the buried solid waste, Environmental Studies for Undergraduate Courses, , 146, , Chapter5.p65, , ent plastics cannot be recycled together. Thus, separation of different plastics before recycling, is necessary. Similarly in recycled paper the fibers are weakened and it is difficult to control, the colour of the recycled product. Recycled, paper is banned for use in food containers to, prevent the possibility of contamination. It very, often costs less to transport raw paper pulp than, scrap paper. Collection, sorting and transport, account for about 90 percent of the cost of, paper recycling. The processes of pulping,, deinking and screening wastepaper are generally more expensive than making paper from, virgin wood or cellulose fibers. Very often thus, recycled paper is more expensive than virgin, paper. However as technology improves the cost, will come down., , 146, , 4/9/2004, 5:09 PM
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will decompose due to the action of microorganisms. At first the waste decomposes aerobically until the oxygen that was present in the, freshly placed fill is used up by the aerobic microorganisms. The anerobes take over producing methane which is poisonous and highly, explosive when mixed with air in concentrations, between 5 and 15 percent. The movement of, gas can be controlled by providing impermeable, barriers in the landfill. A venting system to collect the blocked gas and vent it to the surface, where it can be safely diluted and dispersed into, the atmosphere is thus a necessary component, of the design of sanitary landfills., Even though landfilling is an economic alternative for solid waste disposal, it has become increasingly difficult to find suitable landfilling sites, that are within economic hauling distance and, very often citizens do not want landfills in their, vicinity. Another reason is that no matter how, well engineered the design and operation may, be, there is always the danger of some environmental damage in the form of leakage of, leachates., Incineration is the process of burning municipal solid waste in a properly designed furnace, under suitable temperature and operating conditions. Incineration is a chemical process in, which the combustible portion of the waste is, combined with oxygen forming carbon dioxide, and water, which are released into the atmosphere. This chemical reaction called oxidation, results in the release of heat. For complete oxidation the waste must be mixed with appropriate volumes of air at a temperature of about, 815o C for about one hour. Incineration can, reduce the municipal solid waste by about 90, percent in volume and 75 percent in weight., The risks of incineration however involve airquality problems and toxicity and disposal of the, fly and bottom ash produced during the incineration process. Fly ash consists of finely divided, particulate matter, including cinders, mineral, dust and soot. Most of the incinerator ash is, , bottom ash while the remainder is fly ash. The, possible presence of heavy metals in incinerator, ash can be harmful. Thus toxic products and, materials containing heavy metals (for example, batteries and plastics) should be segregated., Thus extensive air pollution control equipment, and high-level technical supervision and skilled, employees for proper operation and maintenance is required., Thus while sanitary landfills and incinerators have, their own advantages and disadvantages, the, most effective method of solid waste management is source reduction and recycling., , Vermi – Composting, Nature has perfect solutions for managing the, waste it creates, if left undisturbed. The biogeochemical cycles are designed to clear the, waste material produced by animals and plants., We can mimic the same methods that are, present in nature. All dead and dry leaves and, twigs decompose and are broken down by organisms such as worms and insects, and is finally broken down by bacteria and fungi, to form, a dark rich soil-like material called compost., These organisms in the soil use the organic material as food, which provides them with nutrients for their growth and activities. These, nutrients are returned to the soil to be used again, by trees and other plants. This process recycles, nutrients in nature., This soil can be used as a manure for farms and, gardens., , Pollution, , Chapter5.p65, , 147, , 147, , 4/9/2004, 5:09 PM
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Steps for Vermi-Compost, •, , Dig a pit about half a meter square, one, meter deep., , •, , Line it with straw or dried leaves and, grass., , •, , Organize the disposal of organic waste, into the pit as and when generated., , •, , Introduce a culture of worms that is now, produced commercially., , •, , Ensure that the contents are covered, with a sprinkling of dried leaves and soil, everyday., , •, , Water the pit once or twice a week to, keep it moist., , •, , Turn over the contents of the pit ever, 15 days., , •, , In about 45 days the waste will be decomposed by the action of the microorganisms., , •, , The soil derived is fertile and rich in nutrients., , Characteristics of hazardous wastes, A waste is classified as a hazardous waste if it, exhibits any of the four primary characteristics, based on the physical or chemical properties of, toxicity, reactivity, ignitability and corrosivity. In, addition to this waste products that are either, infectious or radioactive are also classified as, hazardous, , Toxic wastes are those substances that are poisonous even in very small or trace amounts., Some may have an acute or immediate effect, on humans or animals causing death or violent, illness. Others may have a chronic or long term, effect slowly causing irreparable harm to exposed persons. Acute toxicity is readily apparent because organisms respond to the toxin, shortly after being exposed. Chronic toxicity is, much more difficult to determine because the, effects may not be seen for years. Certain toxic, wastes are known to be carcinogenic, causing, cancer and others may be mutagenic causing, biological changes in the children of exposed, people and animals., Reactive wastes are those that have a tendency, to react vigorously with air or water, are unstable to shock or heat, generate toxic gases or, explode during routine management. For example, gunpowder, nitroglycerine, etc., , Hazardous wastes, Modern society produces large quantities of, hazardous waste which are generated by chemical manufacturing companies, petroleum refineries, paper mills, smelters and other industries., Hazardous wastes are those that can cause harm, to humans or the environment. Wastes are normally classified as hazardous waste when they, cause or significantly contribute to an increase, in mortality or an increase in serious irreversible, or incapacitating reversible illness or pose a sub-, , Ignitable wastes are those that burn at relatively, low temperatures (less than 60 C) and are capable of spontaneous combustion during storage, transport or disposal. For example, gasoline,, paint thinners, and alcohol., Corrosive wastes are those that destroy materials and living tissue by chemical reaction. For, example, acids and bases., Environmental Studies for Undergraduate Courses, , 148, , Chapter5.p65, , stantial present or potential hazard to human, health or the environment when improperly, treated, stored, transported or disposed of., , 148, , 4/9/2004, 5:09 PM
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Infectious wastes include human tissue from, surgery, used bandages and hypodermic, needles, microbiological materials, etc., , shortening their life span. Lead may also damage nerve tissue which can result in brain disease., , Radioactive waste is basically an output from, the nuclear power plants and can persist in the, environment for thousands of years before it, decays appreciably., , Mercury occurs in several different forms. Mercury is used in the production of chlorine. It is, also used as a catalyst in the production of some, plastics. Industrial processes such as the production of chlorine and plastics are responsible for, most of the environmental damage resulting, from mercury. Our body has a limited ability to, eliminate mercury. In the food web mercury, becomes more concentrated as it is taken up by, various organisms. In an aquatic environment,, mercury can be absorbed by the plankton which, are then consumed by fish. In addition, fish take, up mercury through their gills and by eating, , Environmental problems and health risks, caused by hazardous wastes., As most of the hazardous wastes are disposed, of on or in land the most serious environmental, effect is contaminated groundwater. Once, groundwater is polluted with hazardous wastes, it is very often not possible to reverse the damage., Pesticides are used increasingly to protect and, increase food production. They form residues, in the soil which are washed into streams which, then carry them forwards. The residues may, persist in the soil or in the bottom of lakes and, rivers. Exposure can occur through ingestion,, inhalation and skin contact resulting in acute or, chronic poisoning. Today we have an alternative to the excess use of pesticides through the, use of Integrated Pest Management (IPM). The, IPM system uses a wide variety of plants and, insects to create a more natural process. The, natural balance between climate, soil and insect populations can help to prevent an insect, from overpopulating an area and destroying a, particular crop., Lead, mercury and arsenic are hazardous substances which are often referred to as heavy, metals. Lead is an abundant heavy metal and is, relatively easy to obtain. It is used in batteries,, fuel, pesticides, paints, pipes and other places, where resistance to corrosion is required. Most, of the lead taken up by people and wildlife is, stored in bones. Lead can affect red blood cells, by reducing their ability to carry oxygen and, , Minamata-An important lesson about, mercury, A case of human mercury poisoning which, occurred about forty years ago in the, Minamata bay in Japan taught the world an, important lesson about the dangers of mercury poisoning. A large plastics plant located, near the Minamata bay used a mercury containing compound in a reaction to produce, vinyl chloride a common plastic material. The, left over mercury was dumped into the Bay, along with other wastes from the plant., Though the mercury was in its less toxic inorganic state when dumped microorganisms, at the bottom of the bay converted the mercury into its organic form. This organic mercury then entered into the tissues of fish, which were in turn consumed by the people, living in the area. The contaminated fish thus, caused an outbreak of poisoning killing and, affecting several people. Mothers who had, eaten the contaminated fish gave birth to, infants who showed signs of mercury poisoning. Mercury poisoning is thus called, Minamata Disease., , Pollution, , Chapter5.p65, , 149, , 149, , 4/9/2004, 5:09 PM
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other fish contaminated with mercury. Generally older the fish greater is the mercury concentration in its body. Birds that eat the fish, concentrate even more mercury in their bodies., It is a cumulative poison ( it builds up in the body, over long periods of time) and is known to cause, brain damage., Thousands of chemicals are used in industry, everyday. When used incorrectly or inappropriately they can become health hazards. PCBs, (Polychlorinated biphenyls) are resistant to fire, and do not conduct electricity very well which, makes them excellent materials for several industrial purposes. Rainwater can wash PCBs out, of disposal areas in dumps and landfills thus, contaminating water. PCBs do not break down, very rapidly in the environment and thus retain, their toxic characteristics. They cause long term, exposure problems to both humans and wildlife. PCBs are concentrated in the kidneys and, liver and thus cause damage. They cause reproductive failure in birds and mammals., Vinyl chloride is a chemical that is widely used, in the manufacture of plastic. Usually people are, only exposed to high levels of vinyl chloride if, they work with it or near it but exposure can, also occur from vinyl chloride gas leaks. After a, long continuous exposure (one to three years), in humans, vinyl chloride can cause deafness,, vision problems, circulation disorders and bone, deformities. Vinyl chloride can also cause birth, defects., It is essential to substitute the use of PCBs and, vinyl chloride with chemicals that are less toxic., Polyvinyl chloride use can be lowered by reducing our use of plastics. Thus by reducing waste,, encouraging recycling and using products that, are well made and durable we can greatly reduce our consumption of these chemicals thus, curtailing our exposure to these substances., We may not realize it but many household, chemicals can be quite toxic to humans as well, , Today the most common methods for disposing off hazardous wastes are land disposal and, incineration. In countries where there is abundant land available for disposal for example,, North America land disposal is the most widely, used method. In countries like Europe and Japan where land is not readily available and is, expensive, incineration is the preferred method, for disposal. In spite of strong laws however illegal dumping of these wastes continues. Hazardous waste management must move beyond, burying and burning. Industries need to be encouraged to generate less hazardous waste in, their manufacturing processes. Although toxic, wastes cannot be entirely eliminated, technologies are available for minimizing, recycling and, treating wastes. An informed public can also, contribute in a big way towards this end. It is, essential for us to understand the ill effects of, chemical substances so that we can make informed decisions about its use. We might decide that the benefits of the use of a toxic, substance do not outweigh the risks and choose, not to use it at all or we may decide that it is, acceptable to use a substance under certain, specific circumstances where it is adequately, controlled and exposure to toxic levels is prevented., , 5.4 ROLE OF AN INDIVIDUAL IN PREVENTION OF POLLUTION, There are a host of environmental problems, caused by human actions on the environment., If we are to respond to these problems we have, to recognize that each of us is individually responsible for the quality of the environment we, live in. Our personal actions can either worsen, or improve our environmental quality. Several, Environmental Studies for Undergraduate Courses, , 150, , Chapter5.p65, , as wildlife. Most of the dangerous substances, in our homes are found in various kinds of cleaners, solvents and products used in automotive, care. When these products are used incorrectly, they have the potential to be harmful., , 150, , 4/9/2004, 5:09 PM
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people may feel that environmental problems, can be solved with quick technological fixes., While a majority of individuals would want a, cleaner environment, not many of them want, to make major changes in their lifestyle that, could contribute to a cleaner environment. Decisions and actions taken by individuals to a very, large extent determine the quality of life for, everyone. This necessitates that individuals, should not only be aware of various environmental issues and the consequences of their, actions on the environment but should also, make a firm resolve to develop environmentally, ethical lifestyles., With the help of solar energy, natural processes, developed over billions of years can indefinitely, renew the topsoil, water, air, forests, grasslands, and wildlife on which all forms of life depend,, but only as long as we do not use these potentially renewable resources faster than they are, replenished. Some of our wastes can be diluted,, decomposed and recycled by natural processes, indefinitely as long as these processes are not, overloaded. Natural processes also provide services of flood prevention, erosion control at no, costs at all. We must therefore learn to value, these resources and use them sustainably., , •, , Try to plant trees wherever you can and, more importantly take care of them. They, reduce air pollution., , •, , Reduce the use of wood and paper products wherever possible. Manufacturing paper leads to pollution and loss of forests, which releases oxygen and takes up carbon, dioxide. Try to recycle paper products and, use recycled paper wherever possible., , •, , From the mail you receive reuse as many, envelopes that you can., , •, , Do not buy furniture, doors, window frames, made from tropical hardwoods such as teak, and mahogany. These are forest based., , •, , Help in restoring a degraded area near your, home or join in an afforestation program., , •, , Use pesticides in your home only when absolutely necessary and use them in as small, amounts as necessary. Some insect species, help to keep a check on the populations of, pest species., , •, , Advocate organic farming by asking your, grocery store to stock vegetables and fruits, grown by an organic method. This will automatically help to reduce the use of pesticides., , •, , Reduce the use of fossil fuels by either walking up a short distance using a car pool,, sharing a bike or using public transport. This, reduces air pollution., , •, , Shut off the lights and fans when not, needed., , •, , Don’t use aerosol spray products and commercial room air fresheners. They damage, the ozone layer., , Concepts that help individuals contribute towards a better quality of our environment and, human life., •, , Develop respect or reverence for all forms, of life., , •, , Each individual must try to answer four basic questions:, Where do the things that I consume, come from?, What do I know about the place where, I live?, How am I connected to the earth and, other living things?, What is my purpose and responsibility, as a human being?, , Pollution, , Chapter5.p65, , 151, , 151, , 4/9/2004, 5:09 PM
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•, , Do not pour pesticides, paints, solvents, oil, or other products containing harmful chemicals down the drain or on the ground., , •, , Start individual or community composting, or vemicomposting plants in your neighborhood and motivate people to join in., , •, , Buy consumer goods that last, keep them, as long as possible and have them repaired, as far as possible instead of disposing them, off. Such products end up in landfills that, could pollute ground water., , •, , Do not litter the roads and surroundings just, because the sweeper from the Municipal, Corporation will clean it up. Take care to, put trash into dustbins or bring it back home, with you where it can be appropriately disposed., , •, , Buy consumer goods ages in refillable glass, containers instead of cans or throwaway, bottles., , •, , You must realize that you cannot do everything and have solutions for every problem, in the world. You can however concentrate, on issues that you feel strongly about and, can do something about. Focusing your, energy on a particular issue will help you, get better results., , •, , You could join any of the several NGOs that, exist in our country or become volunteers., Organize small local community meetings, to discuss positive approaches of pollution, prevention., , •, , Learn about the biodiversity of your own, area. Understand the natural and cultural, assets. This would help you to develop a, sense of pride in your city/town/village and, will also help you understand the problems, facing their survival., , •, , Use rechargeable batteries., , •, , Try to avoid asking for plastic carry bags, when you buy groceries or vegetables or, any other items. Use your own cloth bag, instead., , •, , Use sponges and washable cloth napkins,, dish towels and handkerchiefs instead of, paper ones., , •, , Don’t use throwaway paper and plastic, plates and cups when reusable versions are, available., , •, , Recycle all newspaper, glass, aluminum and, other items accepted for recycling in your, area. You might have to take a little trouble, to locate such dealers., , •, , Set up a compost bin in your garden or terrace and use it to produce manure for your, plants to reduce use of fertilizers., , You cannot improve your world by not voting. You have the option to make a choice, rather than complain later on., , •, , It is important that you do not get discouraged at the first sign of trouble. Do not dwell, on the negative aspects. But take positive, actions wherever you can to make the world, a better place to live in., , •, , When talking to elected officials always be, courteous and reasonable. You may disagree with a particular position but be re-, , •, , •, , Try to lobby and push for setting up garbage separation and recycling programs in, your localities., , •, , Choose items that have the least packaging or no packaging., , Environmental Studies for Undergraduate Courses, , 152, , Chapter5.p65, , 152, , 4/9/2004, 5:09 PM
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spectful in doing so as you will gain little by, being hostile and brash., •, , Take care to put into practice what you, preach. Remember environment protection, begins with YOU., , 5.5 POLLUTION CASE STUDIES, A case study of groundwater pollution in, India, An example of groundwater pollution caused, by excessive extraction is that fluoride contamination. Fluorisis is not a localized problem. It has, spread across 19 states and across a variety of, ecological regions ranging from the Thar desert,, the Gangetic plains and the Deccan plateau., Each of these regions are distinct in terms of, rainfall, soil type, groundwater recharge regime,, climatic conditions and hydrology. High fluoride, concentration in groundwater is a natural phenomenon in several countries such as China, Sri, Lanka, West Indies, Spain, Holland, Italy and, Mexico. Experts claim that a fluoride belt, stretches across the Middle East across Pakistan, and India and then into Southeast Asia and the, South of China. According to a report of the, Rajiv Gandhi National Drinking Water mission,, the bedrock of the Indian peninsula consists of, a number of fluoride bearing minerals. When, the bedrock weathers the fluoride leaches into, water and the soil. Although the Indian peninsular bedrock has always been the same, this, problem has only surfaced during the last three, decades. This is related to the over extraction of, groundwater which has resulted in the tapping, of aquifers with high fluoride concentrations., The beginnings of this phenomenon can be, traced back to the 1970s and the 1980s when, there was massive state investment in rural, water development for irrigation as well as for, drinking. Encouraged by state subsidies on diesel and electricity, people invested in diesel and, , submersible pumps in a bid to extract groundwater through borewells. This policy aggravated, the fluoride problem., Fluoride mainly enters the human body through, drinking water where 96 to 99 percent of it, combines with the bones as it has an affinity for, calcium phosphate in the bones. Excess intake, of fluoride can lead to dental fluorosis, skeletal, fluorosis or non-skeletal fluorosis. Dental fluorosis is characterized by discoloured, blackened,, mottled or chalky white teeth. Skeletal fluorosis, leads to severe and permanent bone and joint, deformities. Non-skeletal fluorosis leads to, gastro-intestinal problems and neurological disorders. Fluoride can damage the foetus and, adversely affect the IQ of children., Once fluoride is detected in water, the only solution is to deflouridate it. Various technologies, are available for this process. However the type, of technology to be selected depends upon the, fluoride levels in the water and the volume of, water to be deflouridated. None of the Indian, technologies are however fool-proof., Deflouridation plants and household water treatment kits are stop-gap solutions., , A case study of pesticide pollution in India, One of the most terrifying effects of pesticide, contamination of ground water came to light, when pesticide residues were found in bottled, water. Between July and December 2002, the, Pollution Monitoring Laboratory of the New, Delhi based Center for Science and Environment, (CSE) analysed 17 brands of bottled water both, packaged drinking water and packaged natural, mineral water commonly sold in areas that fall, within the national capital region of Delhi. Pesticide residues of organochlorine and organophosphorus pesticides which are most, commonly used in India were found in all the, samples. Among organochlorines, gammahexachlorocyclohexane (lindane) and DDT were, , Pollution, , Chapter5.p65, , 153, , 153, , 4/9/2004, 5:09 PM
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prevalent while among organophosphorus pesticides, Malathion and Chlorpyrifos were most, common. All these were present above permissible limits specified by the European Economic, Community, which is the norm, used all over, Europe., One may wonder as to how these pesticide residues get into bottled water that is manufactured by several big companies. This can be, traced to several facts. There is no regulation, that the bottled water industry must be located, in ‘clean’ zones. Currently the manufacturing, plants of most brands are situated in the dirtiest, industrial estates or in the midst of agricultural, fields. Most companies use bore wells to pump, out water from the ground from depths varying from 24m to even 152 m below the ground., The raw water samples collected from the plants, also reveled the presence of pesticide residues., This clearly indicated that the source of pesticide residues in the polluted groundwater are, used to manufacture the bottled water. This is, despite the fact that all bottled water plants use, a range of purification methods. Thus obviously, the fault lies in the treatment methods used., These plants use the membrane technology, where the water is filtered using membranes, with ultra-small pores to remove fine suspended, solids and all bacteria and protozoa and even, viruses. While nanofiltration can remove insecticides and herbicides it is expensive and thus, rarely used. Most industries also use an activated, charcoal adsorption process, which is effective, in removing organic pesticides but not heavy, metals. To remove pesticides the plants use reverse osmosis and granular activated charcoal, methods. Thus even though manufacturers, claim to use these process the presence of pesticide residues points to the fact that either, manufacturers do not use the treatment process effectively or only treat a part of the raw, water., , Similarly six months after CSE reported pesticide residues in bottled water it also found these, pesticides in popular cold drink brands sold, across the country. This is because the main ingredient in a cold drink or a carbonated nonalcoholic beverage is water and there are no, standards specified for water to be used in these, beverages in India., There were no standards for bottled water in, India till on September 29, 2000 the Union Ministry of Health and Family Welfare issued a notification (no759(E)) amending the Prevention of, Food Adulteration Rules, 1954. The BIS (Bureau, of Indian Standards) certification mark became, mandatory for bottled water from March 29,, 2001. However the parameters for pesticide, residues remained ambiguous. Following the, report published by CSE in Down to Earth, Vol, 11, no. 18, a series of Committees were established and eventually on 18th July 2003 amendments were made in the Prevention of Food, Adulteration Rules stating that pesticide residues, considered individually should not exceed, 0.0001mg.lit and the total pesticide residues will, not be more than 0.0005 mg/lit that the analysis shall be conducted by using internationally, established test methods meeting the residue, limits specified herein. This notification came into, force from January 1, 2004., , A case study of river pollution in India, Almost all the rivers in India are polluted. The, causes of pollution may also be more or less similar. This is a case study of the river Damodar as, reported in Down to Earth. The 563 km long, Environmental Studies for Undergraduate Courses, , 154, , Chapter5.p65, , The low concentration of pesticide residues in, bottled water do not cause acute or immediate, effect. However repeated exposure even to extremely miniscule amounts can result in chronic, effects like cancer, liver and kidney damage,, disorders of the nervous system, damage to the, immune system and birth defects., , 154, , 4/9/2004, 5:09 PM
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Damodar river originates near Chandwa village, in the Chhotanagpur hills in Bihar’s Palamau, district. It flows through one of the richest mineral belts in the world before draining into the, Hooghly, about 50 km south of Calcutta. Indian industry depends heavily on this region as, 60 percent of the coal consumed in our country, comes from the Chhotanagpur belt. Coal based, industries of all types dot the area because of, locational advantages and the easy availability, of water and power. In addition various industries such as the steel, cement, fertilizer and, explosive plants are also located here. The river, Damodar is polluted with minerals, mine rejects, and toxic effluents. Both its water and its sand, are infested by coal dust and waste from these, industries. There are seven thermal power plants, in the Damodar valley. The states of Bihar and, West Bengal depend almost entirely on this area, for their power requirements. These power, plants not only consume a lot of water but also, dump ash in the valley., , Mining, As underground mines cannot keep pace with, the rising demand, 60 percent of the coal extracted from the area comes from open cast, mines which are responsible for serious land, degradation. The disposal of rock and soil extracted along with the coal only adds to the, problem., , Industries, The industries in the area do not have proper, effluent treatment plants. Among the big coal, based industries the washeries account for the, bulk of the pollution in terms of the total suspended solids (TSS), oil and grease. About 20, percent of the coal handled goes out in the form, of slurry which is deposited in the ponds outside. After the slurry settles, coalfine (the sediment) is collected manually. Due to inadequate, retrieval methods very often the water discharges into the river from the pond carries high, , amounts of fine coal particles and oil thus polluting the river. The other major coal based polluters are the coke oven plants that heat coal to, temperatures as high as 1100oC in the absence, of oxygen to prepare it for use in blast furnaces, and foundries. The volatile components in the, coal are removed, leaving hot, non-volatile coke, in the oven which is washed with huge quantities of water. This water that contains oil and, suspended particles is then discharged into the, river., , Flyash from the thermal power plants, Only one of the thermal power plants has an, electrostatic precipitator to collect the fly ash, while the other just make do with mechanical, dust collectors. As most of these plants are located on the banks of the river the fly ash eventually finds its way into the river. The bottom, ash from the boilers is mixed with water to form, a slurry which is then drained into ash ponds., Most of the ponds are full and in several cases, the drainage pipes are choked. The slurry is, therefore directly discharged into the river., , Effects, The river and its tributaries are the largest source, of drinking water for the huge population that, lives in the valley. On April 2, 1990 about, 200,000 litres of furnace oil spilled into the river, from the Bokaro Steel Plant. This oil traveled, 150 km downstream to Durgapur. For a week, after the incident five million people drank contaminated water in which the oil levels were 40, to 80 times higher than the permissible value of, 0.03 mg/l., The Damodar Action Plan an end-of-the pipe, pollution treatment scheme seeks to tackle effluents. One viable option could be to switch to, less polluting industries and cleaner technology., This would need strong Government initiative, and also a mass movement by people., , Pollution, , Chapter5.p65, , 155, , 155, , 4/9/2004, 5:09 PM
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5.6 DISASTER MANAGEMENT: FLOODS,, EARTHQUAKES, CYCLONES, LANDSLIDES, The Indian subcontinent is very vulnerable to, droughts, floods, cyclones, earthquakes, landslides, avalanches and forest fires. Among the, 36 states and Union territories in the country,, 22 are prone to disasters., Among all the disasters that occur in the country, floods are the most frequently occurring, natural disasters, due to the irregularities of the, Indian monsoon. About 75 percent of the annual rainfall in India is concentrated in three to, four months of the monsoon season. As a result there is a very heavy discharge from the, rivers during this period causing widespread, floods. Approximately 40 million hectares of land, in the country has been identified as being prone, to floods. Major floods are mainly caused in the, Ganga-Brahmaputra-Meghna basin which carries 60 percent of the total river flow of our country., , From management to mitigation of disasters, , India has a long coastline of 5700 kms, which is, exposed to tropical cyclones arising in the Bay, of Bengal and the Arabian sea. The Indian Ocean, is one of the six major cyclone prone regions of, the world. In India, cyclones occur usually between April and May and also between October and December. The eastern coastline is more, prone to cyclones as it is hit by about 80 percent of the total cyclones generated in the region., , It is evident today that human activities are responsible for accelerating the frequency and, severity of natural disasters. Natural occurrences, such as floods, earthquakes, cyclones, etc. will, always occur. They are a part of the environment that we live in. However destruction from, natural hazards can be minimized by the presence of a well functioning warning system combined with preparedness on part of the, community that will be affected. Thus though, traditionally disaster management consisted primarily of reactive mechanisms, the past few, years have witnessed a gradual shift towards a, more proactive, mitigation based approach., , Droughts are a perennial feature in some states, of India. Sixteen percent of the country’s total, area is drought prone. Drought is a significant, environmental problem as it is caused by a lower, than average rainfall over a long period of time., Most of the drought prone areas identified by, the Government lie in the arid and semi-arid, areas of the country., Earthquakes are considered to be one of the, most destructive natural hazards. The impact of, , Till very recently the approach towards dealing, with natural disasters has been post disaster, management involving problems such as evacuation, warnings, communications, search and, rescue, fire-fighting, medical and psychiatric, assistance, provision of relief, shelter, etc. After, the initial trauma and the occurrence of the, natural disaster is over and reconstruction and, rehabilitation is done by people, NGOs and the, Government, its memories are relegated to history., , Disaster management is a multidisciplinary area, in which a wide range of issues that range from, forecasting, warning, evacuation, search and, rescue, relief, reconstruction and rehabilitation, are included. It is also multi-sectoral as it involves, administrators, scientists, planners, volunteers, and communities. These roles and activities span, Environmental Studies for Undergraduate Courses, , 156, , Chapter5.p65, , this phenomenon occurs with so little warning, that it is almost impossible to make preparations against damages and collapse of buildings., About 50 to 60 percent of India is vulnerable to, seismic activity of varying intensities. Most of, the vulnerable areas are located in the Himalayan and sub-Himalayan regions., , 156, , 4/9/2004, 5:09 PM
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the pre-disaster, during disaster and post disaster plans. Since their activities are complementary as well as supplementary to each other there, is a critical need for coordinating these activities., In order to transfer the benefits of scientific research and development to the communities, links must be developed between scientific communities and field agencies. Coordination between Government agencies and NGOs needs, to be built up so that overlap of activities may, be avoided and linkages between the Government and communities are established., Today we have a range of early warning systems for a range of natural hazards. Although, they are more accurate than before and can help, in prediction it is not enough to ensure communities are safe from disasters. This is where disaster mitigation can play an important role., Mitigation means lessening the negative impact, of the natural hazards. It is defined as sustained, action taken to reduce long term vulnerability, of human life and property to natural hazards., While the preparatory, response and the recovery phases of emergency management relate, to specific events, mitigation activities have the, potential to produce repetitive benefits over, time., Certain guidelines if followed can result in an, effective mitigation program., •, , Pre-disaster mitigation can help in ensuring, faster recovery from the impacts of disasters., , •, , Mitigation measures must ensure protection of the natural and cultural assets of the, community., , •, , Hazard reduction methods must take into, account the various hazards faced by the, affected community and their desires and, priorities., , •, , Any mitigation program must also ensure, effective partnership between Government,, scientific, private sector, NGOs and the community., , The main elements of a mitigation strategy are, as follows:, , Risk assessment and Vulnerability analysis, This involves identification of hot spot areas of, prime concern, collection of information on past, natural hazards, information of the natural ecosystems and information on the population and, infrastructure. Once this information is collected, a risk assessment should be done to determine, the frequency, intensity, impact and the time, taken to return to normalcy after the disaster., The assessment of risk and vulnerabilities will, need to be revised periodically. A regular mechanism will therefore have to be established for, this. The use of Geographical Information Systems (GIS) a computer program can be a valuable tool in this process as the primary data can, be easily updated and the corresponding assessments can be made., , Applied research and technology transfer, There is a need to establish or upgrade observation equipment and networks, monitor the, hazards properly, improve the quality of forecasting and warning, disseminate information, quickly through the warning systems and undertake disaster simulation exercises., Thus space technologies such as remote sensing, satellite communications and Global Positioning Systems have a very important role to, play. Government organizations like ISRO (Indian Space Research Organization) can play a, vital role. Similarly Government organizations, the National Building Research Organization, the, Meteorological Department, Irrigation Department, etc. can undertake applied research for, devising locale specific mitigation strategies in, , Pollution, , Chapter5.p65, , 157, , 157, , 4/9/2004, 5:09 PM
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collaboration with educational institutions or, Universities., Such steps could lead to the formulation of locale specific mitigation measures. A combination of scientific knowledge and expertise with, the community based mitigation measures, would not only enhance the database but would, also form the basis of a successful mitigation, strategy., , Public awareness and training, One of the most critical components of a mitigation strategy is the training to be imparted to, the officials and staff of the various departments, involved at the state and the district level. This, enables sharing of information and methodology. The success of a mitigation strategy will, depend to a large extent on the inter-sectional,, inter-departmental coordination and efficient, teamwork. Thus a training program that is designed after assessment of gaps in knowledge,, skills and attitude with respect to the various, tasks that need to be undertaken is a vital component., , Institutional mechanisms, The most important need at the National level, is to strengthen or develop the capacity to undertake disaster mitigation strategies. There is, a need to emphasize on proactive and pre-disaster measures rather than post disaster response. It is thus essential to have a permanent, administrative structure which can monitor the, developmental activities across departments and, provides suggestions for necessary mitigation, measures. The National Disaster Management, Center (NDMC) can perform such a task. Professionals like architects, structural engineers,, doctors, chemical engineers who are involved, with management of hazardous chemicals can, be asked to form groups that can design specific mitigation measures., , Landuse planning and regulations, Long term disaster reduction efforts should aim, at promoting appropriate land-use in the disaster prone areas. Separation of industrial areas, from residential areas, maintaining wetlands as, buffer zones for floods, creation of public awareness of proper land practices and formation of, land-use policies for long term sustainable development is imperative., , Hazard resistant design and construction, In areas that are prone to disasters protection, can be enhanced by careful selection of sites, and the way the buildings are built. Thus it is, essential to promote the knowledge of disaster, resistant construction techniques and practices, among engineers, architects and technical personnel., , Structural and Constructional reinforcement of, existing buildings, It is also possible to reduce the vulnerability of, existing buildings through minor adaptations or, alterations thereby ensuring their safety. This can, be done by insertion of walls on the outside of, the building, buttresses, walls in the interior of, the building, portico fill-in-walls, specially anEnvironmental Studies for Undergraduate Courses, , 158, , Chapter5.p65, , Incentives and resources for mitigation, To a very large extent the success of mitigation, programs will depend upon the availability of, continued funding. There is thus a need to develop mechanisms to provide stable sources of, funding for all mitigation programs. This will, include incentives for relocation of commercial, and residential activities outside the disaster, prone areas. Housing finance companies should, make it mandatory for structures in such hazard prone areas to follow special building specifications. The introduction of disaster linked, insurance should be explored and should cover, not only life but also household goods, cattle,, structures and crops., , 158, , 4/9/2004, 5:09 PM
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chored frames, covering of columns and beams,, construction of new frame system, placing residential electrical equipment above flood level,, designing water storage tanks to be able to withstand cyclonic winds, earthquakes and floods,, etc., , •, , Prevention of over-bank spilling by the construction of embankments and floodwalls., , •, , Improvement of flow conditions in the channel and anti-erosion measures., , •, , Improved drainage., , Floods and mitigation measures, The lower plain regions of India in particular, Bihar, Uttar Pradesh and West Bengal in respect, of the Ganga and Assam in respect of the, Brahmaputra suffer from the adverse effects of, floods every year. The Ganga Brahmaputra basin receives maximum run off within the three, monsoon months. Based on hydrological studies carried out, it is estimated that only 18 percent of the rainwater can be stored in dams,, reservoirs, etc. while 82 percent of the rainwater flows through rivers ultimately into the sea., Floods are therefore a recurring phenomenon, in our country., Floods can be caused by natural, ecological or, anthropogenic factors either individually or as a, combined result. Anthropogenic activities such, as deforestation and shifting cultivation can also, contribute to floods. Forests on the hill slopes, normally exert a sponge effect soaking up the, abundant rainfall and storing it before releasing it in small amounts over a period of time., However when the forests are cleared the rivers turn muddy and swollen during the wet, monsoon season and run dry later on in the year, during the drier periods. An increasing proportion of the rainfall is therefore released shortly, after precipitation in the form of floods., The mitigation measures for floods include both, structural and non-structural measures. The, structural measures include:, •, , Reservoirs for impounding monsoon flows, to be released in a regulated manner after, the peak flood flow passes., , The non-structural measures include:, •, , Flood plain management such as Flood Plain, Zoning and Flood Proofing including Disaster Preparedness, , •, , Maintaining wetlands, , •, , Flood forecasting and warning services, , •, , Disaster relief, flood fighting and public, health measures, , •, , Flood insurance, , Earthquakes and mitigation measures, It has been several years since the earthquake, struck Gujarat on January 26, 2001. In these, years rehabilitation has been done on a massive, scale. Gujarat’s experience has taught that building shelters with less vulnerability to earthquakes, should also take into consideration the specific, needs of the victims instead of being a top down, approach. The role of NGOs in this is very important. Their strength lies in their manpower,, informality in operations and valuable human, resources. Their ability to reach out to the community and sensitivity to local traditions is an, asset in such situations. A report on the various, initiatives in Gujarat reported in Down to Earth, (Vol 12, No. 2) by Mihir Bhatt throws light on, the various developments that have taken place, after the earthquake. According to the report, the initiatives of the International Fund for, , Pollution, , Chapter5.p65, , 159, , 159, , 4/9/2004, 5:09 PM
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Agriculture Development in supporting the Self, Employed Women’s Association and the, Government’s initiative in community based livelihood security for earthquakes and drought victims have the potential to shape future disaster, response and development projects in Gujarat., Similarly the Gujarat Woman’s Economic Development Corporation initiative in reviving, women’s businesses after the calamity also provides many practical lessons in regenerating local economies and artisan markets. This project, supported by the Asian Development Bank, puts, premium on investments in income generation, and asset building after a natural disaster. The, farming kits provided to affected farmers by, Gujarat’s agriculture ministry is also showing, promising results after two seasons. The author, however states that coordination between Government, local NGOs and local community initiatives both for rescue as well as rehabilitation, needs to be strengthened as this can cause delays, overlaps and waste of relief material and, efforts., , Cyclones and mitigation measures, Tropical cyclones are the worst natural hazards, in the tropics. They are large revolving vortices, in the atmosphere extending horizontally from, 150 to1000 km and vertically from the surface, to 12 to 14 km. These are intense low-pressure, areas. Strong winds spiraling anti clockwise in, the Northern Hemisphere blow around the cyclone center at the lower level. At the higher, levels the sense of rotation is just opposite to, that at the lower level. They generally move 300, to 5000 km per day over the ocean. While moving over the ocean they pick up energy from, the warm water of the ocean and some of them, grow into a devastating intensity. On an average about 5 to 6 tropical cyclones form in the, Bay of Bengal and the Arabian Sea every year, out of which 2 to 3 may be severe. More cyclones form in the Bay of Bengal than in the, Arabian Sea. The main dangers from cyclones, , Although one cannot control cyclones, the effects of cyclones can be mitigated through effective and efficient mitigation policies and, strategies. A brief description of the same is, given below., , Installation of early warning systems: Such systems fitted along the coastlines can greatly assist forecasting techniques thus helping in early, evacuation of people in the storm surge areas., Developing communication infrastructure: Communication plays a vital role in cyclone disaster, mitigation and yet this is one of the first services that gets disrupted during cyclones. Amateur Radio has today emerged as a second line, unconventional communications systems and is, an important tool for disaster mitigation., Developing shelter belts: Shelter belts with plantations of trees can act as effective wind and, tide breakers. Apart from acting as effective, windbreakers and protecting soil crops from, being damaged they prevent soil erosion., Developing community cyclone shelters: Cyclone, shelters at strategic locations can help minimizing the loss of human life. In the normal course, these shelters can be used as public utility buildings., , Construction of permanent houses: There is a, need to build appropriately designed concrete, houses that can withstand high winds and tidal, waves., Training and education: Public awareness programs that inform the population about their, response to cyclone warnings and preparedness, can go a long way in reducing causalities., Environmental Studies for Undergraduate Courses, , 160, , Chapter5.p65, , are very strong winds, torrential rains and high, storm tides. Most of the causalities are caused, by coastal inundation by storm tides. This is often followed by heavy rainfall and floods. Storm, surges cause the greatest destruction., , 160, , 4/9/2004, 5:09 PM
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Landuse control and settlement planning: No, residential and industrial units should be ideally, permitted in the coastal belt of 5 km from the, sea as it is the most vulnerable belt. No further, growth of settlements in this region should allowed. Major settlements and other important, establishments should be located beyond 10 km, from the sea., , Landslides and mitigation measures, Landslides are recurring phenomena in the Himalayan region. In the recent years however, intensive construction activity and the destabilizing forces of nature have aggravated the problem. Landslides occur as a result of changes on, a slope, sudden or gradual, either in its composition, structure, hydrology or vegetation. The, changes can be due to geology, climate, weathering, land-use and earthquakes., A significant reduction in the hazards caused, by landslides can be achieved by preventing the, exposure of population and facilities to landslides, and by physically controlling the landslides. Developmental programs that involve modification, of the topography, exploitation of natural resources and change in the balance load on the, ground should not be permitted. Some critical, measures that could be undertaken to prevent, further landslides are drainage measures, erosion control measures such a bamboo check, dams, terracing, jute and coir netting and rockfall control measures such as grass plantation,, vegetated dry masonry wall, retaining wall and, most importantly preventing deforestation and, improving afforestation., Disasters cannot be totally prevented. However, early warning systems, careful planning and preparedness on part of the vulnerable community, would help in minimizing the loss of life and, property due to these disasters., , Pollution, , Chapter5.p65, , 161, , 161, , 4/9/2004, 5:09 PM
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UNIT 6:, , Social Issues and The Environment, , Chapter6.p65, , 6.1 FROM UNSUSTAINABLE TO SUSTAINABLE DEVELOPMENT, , 165, , 6.2 URBAN PROBLEMS RELATED TO ENERGY, , 167, , 6.3 WATER CONSERVATION, RAIN WATER HARVESTING, WATERSHED, MANAGEMENT, 6.3.1 Water conservation, 6.3.2 Rain water harvesting, 6.3.3 Watershed management, , 168, 168, 170, 171, , 6.4 RESETTLEMENT AND REHABILITATION OF PEOPLE; ITS PROBLEMS, AND CONCERNS. CASE STUDIES, , 172, , 6.5 ENVIRONMENTAL ETHICS: ISSUES AND POSSIBLE SOLUTIONS, 6.5.1 Resource consumption patterns and the need for their equitable utilisation, 6.5.2 Equity – Disparity in the Northern and Southern countries, 6.5.3 Urban – rural equity issues, 6.5.4 The need for Gender Equity, 6.5.5 Preserving resources for future generations, 6.5.6 The rights of animals, 6.5.7 The ethical basis of environment education and awareness, 6.5.8 The conservation ethic and traditional value systems of India, , 173, 173, 175, 175, 175, 176, 177, 178, 181, , 6.6 CLIMATE CHANGE, GLOBAL WARMING, ACID RAIN, OZONE LAYER DEPLETION,, NUCLEAR ACCIDENTS AND NUCLEAR HOLOCAUST. CASE STUDIES, 6.6.1 Climate change, 6.6.2 Global warming, 6.6.3 Acid rain, 6.6.4 Ozone layer depletion, 6.6.5 Nuclear Accidents and Nuclear Holocaust, , 182, 182, 183, 184, 185, 186, , Social Issues and The Environment, , 163, , 163, , 4/9/2004, 5:21 PM
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6.7 WASTELAND RECLAMATION, , 187, , 6.8 CONSUMERISM AND WASTE PRODUCTS, , 189, , 6.9 ENVIRONMENT PROTECTION ACT, , 193, , 6.10 AIR (PREVENTION AND CONTROL OF POLLUTION) ACT, , 194, , 6.11 WATER (PREVENTION AND CONTROL OF POLLUTION) ACT, , 196, , 6.12 WILDLIFE PROTECTION ACT, , 197, , 6.13 FOREST CONSERVATION ACT, , 199, , 6.14 ISSUES INVOLVED IN ENFORCEMENT OF ENVIRONMENTAL LEGISLATION, 6.14.1Environment Impact Assessment (EIA), 6.14.2 Citizens actions and action groups, , 201, 201, 202, , 6.15 PUBLIC AWARENESS, 6.15.1 Using an Environmental Calendar of Activities, 6.15.2 What can I do?, , 204, 204, 205, , Environmental Studies for Undergraduate Courses, , 164, , Chapter6.p65, , 164, , 4/9/2004, 5:21 PM
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6.1 FROM UNSUSTAINABLE TO SUSTAINABLE DEVELOPMENT, Until two decades ago the world looked at economic status alone as a measure of human development. Thus countries that were, economically well developed and where people, were relatively richer were called advanced nations while the rest where poverty was widespread and were economically backward were, called developing countries. Most countries of, North America and Europe which had become, industrialized at an earlier stage have become, economically more advanced. They not only exploited their own natural resources rapidly but, also used the natural resources of developing, countries to grow even larger economies. Thus, the way development progressed, the rich countries got richer while the poor nations got, poorer. However, even the developed world has, begun to realise that their lives were being seriously affected by the environmental consequences of development based on economic, growth alone. This form of development did not, add to the quality of life as the environmental, conditions had begun to deteriorate., By the 1970s most development specialists began to appreciate the fact that economic growth, alone could not bring about a better way of life, for people unless environmental conditions were, improved. Development strategies in which only, economic considerations were used, had begun, to suffer from serious environmental problems, due to air and water pollution, waste management, deforestation and a variety of other ill, effects that seriously affected peoples’ well being and health. There were also serious equity, issues between the “haves and the have nots”, in society, at the global and national levels. The, disparity in the lifestyles between the rich and, the poor was made worse by these unsustainable development strategies., Many decades ago, Mahatma Gandhi envisioned a reformed village community based on, , sound environmental management. He stressed, on the need for sanitation based on recycling, human and animal manure and well-ventilated, cottages built of recyclable material. He envisioned roads as being clean and free of dust., His main objective was to use village made goods, instead of industrial products. All these principals are now considered part of sound long-term, development. Gandhiji had designed a sustainable lifestyle for himself when these concepts, were not a part of general thinking., A growing realization of the development strategy that Mahatma Gandhi had suggested many, decades earlier is now accepted by experts on, development across the world. This is based on, his concept that the world could support, people’s needs but not their greed. It has become obvious that the quality of human life has, worsened as economies grew. The world now, appears to be at a crossroad. It has taken the, path of short term economic growth and now, suffers the consequences of environmental degradation at the cost of loss of ‘quality of human, life’. The earth cannot supply the amount of resources used and wasted by the economically, well off sectors of society as well as that required, for day to day sustenance of the ever growing, population in less developed countries. Society, must thus change its unsustainable development, strategy to a new form where development will, not destroy the environment. This form of sustainable development can only be brought about, if each individual practices a sustainable lifestyle, based on caring for the earth., It was also realized that these were not simple, issues. Indira Gandhi said in the Stockholm Conference in 1972 that poverty was the greatest, polluter. This meant that while the super rich, nations had serious environmental problems, the, under-developed in Asia, Africa and South, America had a different set of environmental, problems linked to poverty. Developing countries were suffering the consequences of a rapidly expanding human population with all its, , Social Issues and The Environment, , Chapter6.p65, , 165, , 165, , 4/9/2004, 5:21 PM
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effects on the over utilization of natural resources., Thus increasingly the world began to see the, need for a more equitable use of earth resources., The control over natural resources and the, wealth that it produces also begins to create, tensions between people that can eventually, lead to both strife within a country and wars, between nations. This is also a major cause for, the loss of quality of life. How then could a new, form of development be brought about that, could solve the growing discontent in the world?, It has become obvious that development must, begin to change from aiming at short term economic gains to a long term sustainable growth, that would not only support the well being and, quality of life of all people living in the world, today but that of future generations as well., The current strategies of economic development, are using up resources of the world so rapidly, that our future generations, the young people, of the world, would have serious environmental problems, much worse than those that we, are facing at present. Thus current development, strategies have come to be considered unsustainable for the world’s long-term development., The newer concept of development has come, to be known as “Sustainable Development”. The, nations of the world came to clearly understand, these issues at the Rio Conference in 1992. Several documents were created for the United, Nations Conference on Environment and Development (UNCED), which brought out the fact, that environment and development were closely, connected and that there was a need to ‘care, for the Earth’., Sustainable development is defined as development that meets the needs of the, present without compromising the ability, of future generations to meet their own, needs. It also looks at the equity between countries and continents, races and classes, gender, and ages. It includes social development and, , To ensure sustainable development, any activity that is expected to bring about economic, growth must also consider its environmental, impacts so that it is more consistent with long, term growth and development. Many ‘development projects’, such as dams, mines, roads,, industries and tourism development, have severe environmental consequences that must be, studied before they are even begun. Thus for, every project, in a strategy that looks at sustainable development, there must be a scientifically, and honestly done EIA, without which the, project must not be cleared., Large dams, major highways, mining, industry,, etc. can seriously damage ecosystems that support the ecological health of a region. Forests, are essential for maintaining renewable resources, reducing carbon dioxide levels and, maintaining oxygen levels in the earth’s atmosphere. Their loss impairs future human development. Loss of forests depletes biodiversity, which has to be preserved to maintain life on, earth. Major heavy industries if not planned carefully lead to environmental degradation due to, air and water pollution and generate enormous, quantities of waste that lead to long term environmental hazards. Toxic and Nuclear wastes, can become serious economic problems as getting rid of them is extremely costly. Thus the, economic benefits of a project must be weighed, against the possible environmental costs before, a project is permitted., , Environmental Studies for Undergraduate Courses, , 166, , Chapter6.p65, , economic opportunity on one hand and the requirements of environment on the other. It is, based on improving the quality of life for all,, especially the poor and deprived within the carrying capacity of the supporting ecosystems. It, is a process which leads to a better quality of, life while reducing the impact on the environment. Its strength is that it acknowledges the, interdependence of human needs and environmental requirements., , 166, , 4/9/2004, 5:21 PM
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We as citizens of our Nation, and increasingly, as citizens of one common future at the global, level, must constantly monitor the pattern of, development. If we see that a development, project or an industry is leading to serious environmental problems, it is our duty to bring this, to the attention of authorities such as the local, administration, the Forest Department or the, Pollution Control Board, to look into the issue., Further if new development projects are being, planned in and around the place where we live, it is our duty to see that this is brought about in, accordance with environmental safeguards., While we all need to think globally, we need to, act locally. We have to see to it that we change, development from its present mandate of rapid, economic growth without a thought for future, ecological integrity, to a more sustainable ecologically appropriate strategy., If new projects of a large size are to be passed, Government has made it compulsory to publish, the summary report of the Environmental Impact Assessment (EIA) and conduct a ‘Public, Hearing’. It is essential that all of us as responsible citizens read, evaluate and respond to such, public hearings held in our area and make comments on the possible impacts of the project. In, many situations there are proponents of the, project who only look at their own rapid economic gains. It is for citizens as concerned individuals and groups to counter these vested, interests so that our environment is not degraded further. Life has to be made more livable for all. We cannot support the economic, growth of one sector of society while we permit environmental degradation to destroy the, lives of the less fortunate., , 6.2 URBAN PROBLEMS RELATED TO ENERGY, Urban centers use enormous quantities of energy. In the past, urban housing required relatively smaller amounts of energy than we use at, present. Traditional housing in India required, , very little temperature adjustments as the materials used, such as wood and bricks handled, temperature changes better than the current, concrete, glass and steel of ultra modern buildings., , Embodied energy, Materials like iron, glass, aluminium, steel,, cement, marble and burnt bricks, which are, used in urban housing, are very energy intensive. The process of extraction, refinement, fabrication and delivery are all energy, consuming and add to pollution of earth, air, and water. This energy consumed in the process is called embodied energy., , Until the 1950s many urban kitchens were based, on fuelwood or charcoal. This was possible and, practical when homes had chimneys and kitchens were isolated from the rest of the house., Smoke became a problem once this changed to, apartment blocks. Kerosene thus became a, popular urban fuel. This changed to electrical, energy and increasingly to natural gas by the, 1970s in most parts of urban India., Urban centers in hot climates need energy for, cooling. The early systems of fans changed into, air-conditioning, which consumes enormous, quantities of energy. New buildings in our country have taken to using large areas covered by, glass. While in cold climates this uses the green, house effect to trap the warmth of the sun inside, in our hot climate this adds several degrees, to the temperature inside. Thus it requires even, more energy to run large central air conditioning units. High rise buildings in urban centers, also depend on energy to operate lifts and an, enormous number of lights., , Social Issues and The Environment, , Chapter6.p65, , 167, , 167, , 4/9/2004, 5:21 PM
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CASE STUDY, , 6.3 WATER CONSERVATION, RAINWATER, HARVESTING, WATERSHED MANAGEMENT, , Energy efficiency, , 6.3.1 Water Conservation:, , Urban residential and commercial facilities, are responsible for approximately 35% of, USA’s greenhouse gas emissions. Buildings, need to be made energy efficient and reduce carbon dioxide emissions, which cause, ‘heat islands’ or pockets of high temperature over these urban areas., , Conserving water has become a prime environmental concern. Clean water is becoming increasingly scarce globally. With deforestation, surface runoff increases and the sub soil water, table drops as water has no time to seep slowly, into the ground once vegetation is cleared., , Urban transport depends on energy mainly from, fossil fuels. Most urban people use their own, individual transport rather than public transport, systems for a variety of reasons. Urban transport in different cities and even different parts, of a city are either inefficient or overcrowded., Thus even middle income groups tend to use, their own private vehicles. This means more and, more vehicles on the road which leads to traffic, congestion, waste of time for all the commuters, and a great load of particulate matter and, carbon monoxide from the exhaust of vehicles., This causes a rise in the number of people having serious respiratory diseases. Thus there is a, need to develop a more efficient public transport system and discourage the use of individual, vehicles in all our urban areas., Each of us as an environmentally conscious individual must reduce our use of energy. An unnecessary light left on carelessly adds to energy, use. Imagine the amount of energy wasted by, thousands of careless people. If we learned to, save electricity, we would begin to have a more, sustainable lifestyle., , As many areas depend on wells, it has become, necessary to go on making deeper and deeper, wells. This adds to the cost and further depletes, underground stores of water. This could take, years to recharge even if the present rate of, extraction is reduced which seems hardly possible in most situations., As deforestation and desertification spreads due, to extensive changes in land use the once perennial rivers are becoming increasingly seasonal., In many areas the small streams run dry soon, after the monsoon as the water table drops further and further below the surface. To this is, added serious problems caused by rapid surface, flow of water during the rains, which leads to, extensive floods with loss of life and property., When we waste water, we do not realise that it, is affecting the lives of all of us in so many different ways. Water has to be equitably and fairly, distributed so that household use, agriculture, and industry all get a share of the water. It’s, over use and misuse due to various activities that, waste water or cause pollution has led to a serious shortage of potable drinking water. Thus, water conservation is linked closely with overall, human well being., Traditional systems of collecting water and using it optimally have been used in India for many, generations. These have been forgotten in the, recent past. Conserving water in multiple small, percolation tanks and ‘jheels’ was important in, Environmental Studies for Undergraduate Courses, , 168, , Chapter6.p65, , 168, , 4/9/2004, 5:21 PM
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traditional forms of agriculture. Villages all over, the country had one or more common ‘talabs’, or tanks from which people collected or used, water carefully., As women had to carry water to their homes, over long distances, this was a time consuming, and laborious activity, thus the water could not, be wasted. Many homes had a kitchen garden, that was watered by the wastewater. Conservation of water was done in traditional homes, through a conscious effort., , CASE STUDY, Pani Panchayat – Pune District,, Maharashtra, Mahur village in Pune District of Maharashtra, is situated in a drought prone area. People, were not able to grow a good crop in most, years. Clean drinking water was also scarce., Vilasrao Salunkhe initiated a movement, known as Pani Panchayat, to conserve water in this drought prone area. Watershed, development was initiated on a barren and, uncultivated piece of land belonging to a, temple. Conservation of soil and water harvesting through a comprehensive microwatershed management program gradually, led to a surplus of water. Out of the 16 hectares of land in the village, 9.6 hectares were, brought under irrigation, 2.4 hectares was, afforested and 4 hectares was converted into, percolation tanks. Wells and field bunds were, built. While 200 quintals of grains were produced on 24 acres of Salunkhe’s land, 40, acres in the same area yielded only 10 quintals. This made other villagers follow suit. The, area rapidly turned green and productive., , During the British period many dams were built, across the country to supply water especially to, growing urban areas. Post independence, India’s, policy on water changed towards building large, dams for expanding agriculture to support the, green revolution. While this reduced the need, to import food material and removed starvation, in the country, the country began to see the, effects of serious water shortages and problems, related to its distribution. The newer forms of, irrigated agriculture such as sugarcane and other, water hungry cash crops required enormous, quantities of water. Finally however, such irrigated areas become waterlogged and unproductive. As excess water evaporates rapidly from, the surface of heavily irrigated croplands, it pulls, up subsoil water along with salts to the surface, of the soil. This leads to salinization by which, the land becomes unproductive. Reducing the, high salinity levels in soil is extremely expensive, and frequently impossible., With all these ill effects of the poorly conceived, management of water at the national and local, level there is a need to consider a new water, policy for the country., Saving water in agriculture: Drip irrigation supplies water to plants near its roots through a, system of tubes, thus saving water. Small percolation tanks and rainwater harvesting can provide water for agriculture and domestic use., Rainwater collected from rooftops can be stored, or used to effectively recharge subsoil aquifers., Saving water in urban settings: Urban people, waste large amounts of water. Leaking taps and, pipes are a major source of loss of water. Canals and pipes carrying water from dams to the, consumer lead to nearly 50% loss during transfer. Reducing the demand for water by saving it, is more appropriate than trying to meet growing demands., , Social Issues and The Environment, , Chapter6.p65, , 169, , 169, , 4/9/2004, 5:21 PM
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6.3.2 Rain water Harvesting, As our world faces serious water shortages, every drop of water we can use efficiently becomes, of great value. One method is to manage rain, water in such a way that it is used at the source., If as much water as possible is collected and, stored this can be used after the rainy season is, over. In many parts of the world especially in, very dry areas this has been traditionally practiced. However the stored water has to be kept, pollution free and clean so that it can be used, as drinking water. Stored water can grow algae, , and zooplankton (microscopic animals). This can, be pathogenic and cause infections. Thus keeping the water uncontaminated is of great importance., Current technologies of rainwater harvesting, require that all roof and terrace water passes, down into a covered tank where it can be stored, for use after the monsoon. This is most advantageous in arid areas where clean water is very, scarce. However there are practical difficulties, such as constructing large storage tanks which, are expensive., , CASE STUDY, Mewar, Rajasthan, The Mewar region of Rajasthan has a rich, legacy of traditional water harvesting systems, to share the available water for cultivation., There are various types of rainwater harvesting systems., , Medhbandi: This is a stone embankment built, on a hill slope to help create a level field for, cultivation. It controls erosion and conserves, moisture., Naada/bandha: These are stone check dams, across streams or gullies that are constructed, to capture runoff on a stretch of fertile land, that is submerged in water during the monsoon. The land not only becomes more fertile, after trapping silt, but also retains substantial, quantities of water in the soil. These dams are, constructed in phases over several years. The, height is slowly increased up to the right height, of the check dam which determines the size, of the naada., Hembar: These are small temporary dams constructed with stones, twigs and mud over a, seasonal stream when water flows in it is re-, , Chak: Chak is a big plot of land, usually a, charnot or village pasture land, enclosed by a, stone boundary wall called kot. Tree plantations, seeding of grass for fodder, contour, bunds with trenches and loose stone check, dams are developed in the chak. The chak is, used for fodder and fuel wood. It reduces soil, erosion and enhances recharge of ground, water., Talab: The Mewar region is well-known for, its built reservoirs (talabs). Udaipur City is famous for its large number of talabs, and is, called the lake city. A small reservoir of less, than five bighas is called talai, a medium sized, lake is called bandh or talab and a bigger lake, is called sagar or samand., Saza kuva: This is an open dug well which has, several owners. In Mewari language, saza, means partner. This is an important method, for irrigation in the Aravalli hills. About 70,000, wells in the Udaipur District provide water for, 80% of the area under irrigation and provide, water for their owners. These are considered, common property resources., Environmental Studies for Undergraduate Courses, , 170, , Chapter6.p65, , duced to a point that it cannot be taken directly to the fields for irrigation., , 170, , 4/9/2004, 5:21 PM
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Another way of using rooftop rainwater harvesting is to collect it so that it percolates into, the ground to recharge wells instead of flowing, over the ground into rivers. Thus by recharging, ground water harvested from rooftops, the, water table rises and the surrounding wells retain water throughout the year., , 6.3.3 Watershed Management:, Rivers originate in streams that flow down, mountains and hill slopes. A group of small, streams flow down hillsides to meet larger, streams in the valley which forms the tributaries of major rivers. The management of a single, unit of land with its water drainage system is, called watershed management. It is a technique, that has several components. This includes soil, and water management and developing vegetative cover. The natural drainage pattern of a, watershed unit if managed appropriately can, bring about local prosperity by a year round, abundance of water that improves the quality, of human life in the area., As it provides water throughout the year, this, improves health in the community, as clean, water becomes available. Watershed management enhances the growth of agricultural crops, and even makes it possible to grow more than, one crop in a year in dry areas., Watershed management begins by taking control over a degraded site through local participation. People must appreciate the need to, improve the availability of water both in quantity and quality for their own area. Once this is, adequately demonstrated, the community begins to understand the project, people begin to, work together in the activities that lead to good, watershed management., , along contours of the hill to hold the rainwater, and allow it to percolate into the ground. This, ensures that underground stores of water are, fully recharged. This is enhanced by allowing, grasses and shrubs to grow and by planting trees, (mainly local species) which hold the soil and, prevents it from being washed away in the, monsoon. Local grass cover can however only, increase if free grazing of domestic animals is, prevented by stall feeding., The next measure is to make ‘nala’ plugs in the, streams so that the water is held in the stream, and does not rush down the hillside. In selected, sites, several small check dams are built which, together hold back larger amounts of water. All, these measures constitute sound watershed, management. It improves the water table and, keeps the streams and nalas flowing throughout the year., , Watershed management principles:, This is a land management program that, looks at a region from the perspective of all, its water related issues. It can be used to, manage a river from its source to its termination. Watershed management could also, consider the management of a single valley, as a unit, based on its small streams. Saving, water from its local source by allowing it to, percolate into the ground by nala plugs and, check dams instead of allowing it to run off, rapidly along the surface during the monsoon, is a major aspect of good watershed, management. This allows underground aquifers to fill so that ground water is recharged., Deforestation is a major cause of poor water supply. Afforesting such degraded areas, is an important aspect of watershed management., , The first technical step is to take appropriate, soil conservation measures. This is done by constructing a series of long trenches and mounds, Social Issues and The Environment, , Chapter6.p65, , 171, , 171, , 4/9/2004, 5:21 PM
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6.4 RESETTLEMENT AND REHABILITATION, OF PEOPLE: ITS PROBLEMS AND CONCERNS, Major projects such as dams, mines, expressways, or the notification of a National Park disrupts the lives of the people who live there and, may also require moving them to an alternative, site. None of us would like to give up the home, we grew up in. Uprooting people is a serious, issue. It reduces their ability to subsist on their, traditional natural resource base and also, creates great psychological pressures. Especially, tribal people, whose lives are woven closely, around their own natural resources, cannot, adapt to a new way of life in a new place. Thus, no major project that is likely to displace people, can be carried out without the consent of the, local people. In India, lakhs of people have been, unfairly displaced by thousands of dams created, since independence to drive the green revolution. The dams have been built virtually at the, cost of these poor local people who have been, powerless to resist the Government’s will. The, Government is expected to find ‘good’ arable, land to resettle displaced persons and provide, them with an adequate rehabilitation package, to recover from the disruption. This has rarely, occurred to the satisfaction of the project affected individuals. In many cases across the, country, this has not been implemented satisfactorily for decades., Resettlement requires alternate land. However,, in our overpopulated country, there is no arable high quality land available. Thus most, project affected persons are given unusable, wasteland. Rehabilitation involves more than just, giving land. In most cases this is also not adequately done. The greatest battle to save their, own precious land has been carried out by the, tribal people of the Narmada River. They have, fought to save their lands for decades. The, Narmada Bachao Andolan has shown how bitter people can get over this issue., , The Tehri Project, The Tehri Dam in the outer Himalayas in Uttar, Pradesh, when finished will submerge Tehri, town and nearly 100 villages. Since the dam, was sanctioned in 1972, local people have, been opposing the dam and resisting its construction. Scientists, environmentalists and, other groups have also opposed this dam., Little is done to ensure proper rehabilitation, and compensation for nearly a lakh of people, who will be uprooted from their homes as a, result of this dam, with little hope of rehabilitation, as no alternative land is available., There is also emotional and psychological, trauma caused by forcibly removing people, from their homeland where their families, have lived for centuries., , Resettlement not only puts pressure on the, project affected people but also on the people, who have been living in the area that has been, selected for resettlement. Thus both the communities suffer and conflict over resources is a, distinct possibility in future., , CASE STUDY, Indigenous tribes, It is not flora and fauna alone that is under, the threat of extinction. Among the many, tribes across the globe, the Jarawa of the, Andamans in the Indian Ocean are dwindling. Dispossession of their customary rights, over land has put their survival at risk. They, have been compelled to give up their traditional lifestyles resulting in rapidly diminishing indigenous population., Environmental Studies for Undergraduate Courses, , 172, , Chapter6.p65, , CASE STUDY, , 172, , 4/9/2004, 5:21 PM
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There are however situations where communities request for shifting to a new site. This is, often observed where people live inside or on, the periphery of a National Park or Wildlife Sanctuary. In these situations, such as the Gir in, Gujarat, the local people have asked to be given, alternate land where they could live peacefully, away from lions that kill their cattle, but the Government has been unable to find suitable areas, where they can be shifted for decades., , 6.5 ENVIRONMENTAL ETHICS: ISSUES AND, POSSIBLE SOLUTIONS, Environmental ethics deals with issues related, to the rights of individuals that are fundamental to life and well being. This concerns not only, the needs of each person today, but also those, who will come after us. It also deals with the, rights of other living creatures that inhabit our, earth., , 6.5.1 Resource consumption patterns and, the need for their equitable utilisation:, Environmental ethics deals with issues that are, related to how we utilise and distribute resources. Can individuals justifiably use resources, so differently that one individual uses resources, many times more lavishly than other individuals, who have barely enough to survive? In a just, world, there has to be a more equitable sharing, of resources than we encounter at present. The, just distribution of resources has global, national, and local concerns that we need to address., There are rich and poor nations. There are rich, and poor communities in every country. And, there are rich and poor families. In this era of, modern economic development, the disparity, between the haves and have-nots is widening., Our human environments in the urban, rural and, wilderness sectors, use natural resources that, shift from the wilderness (forests, grasslands,, wetlands, etc.) to the rural sector, and from there, , to the urban sector. Wealth also shifts in the, same direction. This unequal distribution of, wealth and access to land and its resources is a, serious environmental concern. An equitable, sharing of resources forms the basis of sustainable development for urban, rural and wilderness dwelling communities. As the political, power base is in the urban centers, this itself, leads to inequalities and a subsequent loss of, sustainability in resource management in the, rural and even more so for forest dwelling, people., In 1985, Anil Agarwal published the first report, on the Status of India’s Environment. It emphasized that India’s environmental problems were, caused by the excessive consumption patterns, of the rich that left the poor poorer. It was appreciated for the first time that tribals, especially, women and other marginalized sectors of our, society, were being left out of economic development. There are multiple stakeholders in Indian society who are dependent on different, natural resources which cater directly or indirectly to their survival needs. Anil Agarwal, brought forth a set of 8 propositions which are, of great relevance to the ethical issues that are, related to environmental concerns. These include:, 1. Environmental destruction is largely caused, by the consumption of the rich., 2. The worst sufferers of environmental destruction are the poor., 3. Even where nature is being ‘recreated’, as, in afforestation, it is being transformed, away from the needs of the poor and towards those of the rich., 4. Even among the poor, the worst sufferers, are the marginalised cultures and occupations, and most of all, women., , Social Issues and The Environment, , Chapter6.p65, , 173, , 173, , 4/9/2004, 5:21 PM
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5. There cannot be proper economic and social development without a holistic understanding of society and nature., 6. If we care for the poor, we cannot allow, the Gross Nature Product to be destroyed, any further. Conserving and recreating nature has become our highest priority., 7. Gross Nature Product will be enhanced only, if we can arrest and reverse the growing, alienation between the people and the common property resources. In this we will have, to learn a lot from our traditional cultures., 8. It is totally inadequate to talk only of sustainable rural development, as the World, Conservation Strategy does. We cannot, save the rural environment or rural people, dependent on it, unless we can bring about, sustainable urban development., , Equitable use of forest resources: We, think of forests as being degraded due to, fuelwood collection by poor rural communities, but forget that the rich use much greater, quantities of timber. Biomass based industries include cotton textiles, paper, plywood,, rubber, soap, sugar, tobacco, jute, chocolate, food processing and packaging. These, need land, energy, irrigation and forest resources. Do each of us realise this when we, utilise, use excessively or waste these resources that we get indirectly from the forests?, Who pays for the cost of environmental degradation? Most sections of society do not feel the, direct effects of degradation of the environment, till it is too late. Those who suffer most are the, poor, especially rural women, and tribal people, who are dependent on forests. Traditional fishermen who are dependent on streams and rivers, and coastal people who fish and catch, , Several marginalised sectors of society are most, affected by deforestation, or the loss of grassland tracts, or the deterioration of perennial, water sources. All these effects can be linked to, unsustainable increasing pressures on land and, natural resources., , “I am often amazed and extremely angry,, when people talk about Environment Education for the villages. It is the so-called, educated people who need Environment, Education more than anyone else”., – Anil Agarwal, ‘Human-Nature Interactions in a Third World Country’., , The well to do educated urban dweller consumes much larger quantities of resources and, energy, than the traditional rural individual. Urban dwellers who are far removed from the, source of natural resources that sustain their lives, thus require exposure to a well-designed environment education program to appreciate these, issues. While the rural people have a deep insight on the need for sustainable use of natural, resources and know about methods of conservation, there are however several newer environmental concerns that are frequently outside, their sphere of life experiences. Their traditional, knowledge of environmental concerns cannot, be expected to bring about an understanding, of issues such as global warming, or problems, created by pollution, pesticides, etc. These, people thus require a different pattern of environment education that is related to their gaps, in information. With the rapidly changing rural, scenario the development that is thrust on unsuspecting rural communities needs to be adEnvironmental Studies for Undergraduate Courses, , 174, , Chapter6.p65, , crustacea, are seriously affected by the degradation of aquatic ecosystems. Fuelwood gatherers from different types of forests, and, pastoralists who are dependent on common, grazing lands suffer when their resources are, depleted., , 174, , 4/9/2004, 5:21 PM
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dressed through locale specific environment, awareness programs designed specifically for, rural school children and adults. This must also, use their local traditional knowledge systems as, a base on which modern concepts can be built,, rather than by fostering concepts that are completely alien to their own knowledge systems., , such as in South and Southeast Asia and South, America. People living in the economically advanced nations use greater amounts of resources, and energy per individual and also waste more, resources. This is at the cost of poor people who, are resource dependant and live in developing, nations., , Common property resources in India once included vast stretches of forests, grazing lands, and aquatic ecosystems. When the British found, that they were unable to get enough wood for, ship building and other uses they converted forest areas into Government ‘Reserved Forests’ for, their own use to grow timber trees. This alienated local people from having a stake in preserving these resources. This in turn led to, large-scale losses in forest cover and the creation of wasteland. In the past, in traditional, villages that were managed by local panchayats,, there were well defined rules about managing, grazing lands, collecting forest resources, protecting sacred groves, etc. that supported conservation. There was a more or less equitable, distribution that was controled by traditional, mechanisms to prevent misuse of common property resources. Any infringement was quickly, dealt with by the panchayat and the offender, was punished. Common property resources, were thus locally protected by communities. As, landuse patterns changed, these mechanisms, were lost and unsustainable practices evolved,, frequently as a result of an inadequately planned, development strategy., , The economically advanced West has exploited, their own natural resources to such an extent, that they have exhausted them nearly everywhere. They now buy their resources from resource rich but economically deprived nations, at a low cost. This depletes the developing nations of natural resources on which their poor, depend for their livelihood., , 6.5.2 Equity – Disparity in the Northern and, Southern countries, Environmental ethics are concerned with, who, owns resources and how they are distributed., This can be looked upon at different levels. At, the global level it deals with the great North –, South divide between the rich industrialized, nations of North America and Europe, as against, the needs of developing countries of the South, , Changing this unfair economic practice to a, more just and fair way in managing trade would, require a new thinking on the part of people, who live in the super rich countries., , 6.5.3 Urban – rural equity issues, The common property of rural communities has, increasingly been used to supply the needs of, the urban sector. Land itself that was once held, as a common property resource of villages is, being taken over by the urban and industrial, sectors as it expands. The rural sector not only, supplies food, but also a part of the energy needs, (mainly fuelwood) to most towns and cities in, India, at a pittance. As a result, the commons of, the rural sector are being depleted of their resources. Thus while the cities get richer, the rural sector, especially the landless, get poorer., The urban rich must appreciate where their resources are derived from and be willing to pay a, fair price for using them., , 6.5.4 The need for Gender Equity, All over India, especially in the rural sector,, women work on the whole longer hours than, , Social Issues and The Environment, , Chapter6.p65, , 175, , 175, , 4/9/2004, 5:21 PM
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men. The life of a woman is enmeshed in an, inextricable cycle of poverty. In attempting to, eke out a living from their environment, they, must constantly collect fuelwood for their homes, and for sale to nearby urban areas. They laboriously collect fodder for their cattle. They have, to trudge several kilometers to reach a reasonably clean water source. And finally must cook, meals in a smoky unhealthy atmosphere on crop, waste or other inefficient sources of energy. All, this can take 10 to 12 hours a day of very hard, work, every day of the year. There is thus the, question of who should control the environmental resources of a rural community. Unfortunately it is the men who play a decisive role in, managing the village commons and its resources, whereas it should be the local women whose, lives are deeply linked with the utilisation and, conservation patterns of natural resources, who, should be decision makers at the local level. Unfortunately women have not been given an, equal opportunity to develop and better their, lot. This begins with the lack of attention given, to girls whose education is always given less attention than the boys in the family. Unless society begins to see that development cannot be, planned by a male dominated society from the, male perspective alone, will we be able to create a better living environment for women and, their children?, The great divide between women and men is, most apparent in communities that live near, forests and have by tradition made the woman, play a greater role than men in collection of, natural resources. Women fetch water, collect, fuelwood, fruit, medicinal products, etc. day in, and day out, while the men work only sporadically in the fields. This disparity in the lives of, women and men has also led to a lower access, to education and health care for girl children., This has deep implications for the rate of utilization of natural resources and its conservation., Rural women who are intimately connected to, resources, appreciate the value of conserving, , 6.5.5 Preserving resources for future generations:, Can we use up all the resources of the world,, leaving nothing for our future generations? This, ethical issue must be considered when we use, resources unsustainably. If we overuse and misuse resources and energy from fossil fuels, our, future generations would find survival much, more difficult. A critical concern is to preserve, species and natural undisturbed ecosystems that, are linked with bioresources, which must be, protected for the use of future generations. Our, generation does not own the world’s resources, to do whatever we please with them. Just as, our ancestors have left resources for us, it is our, duty to leave them behind for our future generations. These unborn people have a right to, these resources. We only hold the world as trustees so that future generations can also survive., Our current development strategies have led to, environmental resources being overused and, misused by our present generation, without a, thought for the needs of future unborn generations. We need to appreciate that the next, generation and those that will come later also, have a right to the earth’s natural resources. As, they are not here today to exercise their rights,, it is our generation’s responsibility to appreciate the needs of future generations. We have, no right to destroy their claim to the use of the, earth’s resources just because of the accident, of being born before them. Development strategies have not looked at the sustainable levels, at which we can use resources so that the rights, of future generations are protected. We are not, given the earth so that we can use up its resources. It is given to us to hold in trust so that, Environmental Studies for Undergraduate Courses, , 176, , Chapter6.p65, , natural resources more deeply than men. Thus, several environmental movements such as, Chipko have been more strongly supported by, local women folk rather than men., , 176, , 4/9/2004, 5:21 PM
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future generations are given their just share of, the earth’s resources., , 6.5.6 The rights of animals:, Can man, a single species, use and severely exploit the earth’s resources which we share with, billions of other plant and animal species? Within, our world there are a variety of living beings., The plants and animals that share the earth with, us too have a right to live and share our earth’s, resources and living space. We have no right to, push a species that has taken millions of years, to evolve towards extinction. Not only do wild, and domesticated animals have a right to life,, but have the right to a dignified existence. Cruelty to an animal is no different ethically from, cruelty to another human being., , Mahatma Gandhi’s philosophy was based on, the assumption that human beings were not, masters of the other forms of life. He believed that humans were ‘trustees of the, lower animal kingdom’., , Human beings are one small cog in the wheel, of life on earth. We frequently forget that man, has learned to exploit nature and other species, well beyond what we should use justifiably. Every plant and animal has a right to life as a part, of our earth’s community of living things. While, , nature by itself has natural prey-predator relationships, left to itself, nature maintains a balance in each ecosystem. While evolution has, developed a system whereby species become, extinct and new ones evolve to fill the world’s, ecosystems with new plant and animal species,, it is man alone that has been responsible for, the recent rapid decline in the number of species on earth. Much more important man is now, reducing the abundance levels of so many species that in the near future we will in all probability create a major extinction spasm on earth, that will seriously endanger the existence of, mankind. Thus endangering the existence of, wild plants and animals and bringing them close, to the brink of extinction is not only unfair to a, species but also to future generation of people, who may find them of great use. Quite apart, from the use of these species, there is a strong, ethical basis for the rights of animals and plants, to exist on earth. Every individual, human or, animal, that is living has feelings and emotions., Cruelty to animals is a crime that must be regarded seriously and action must be taken, against offenders. Animals have a right to a dignified existence, and their life, well-being and, liberty must be respected. While dominating, over the animal world due to his superior intelligence, man cannot remain unfeeling to the, right to life and well being of other species. There, is a growing awareness of animal rights in our, country and cruelty to animals is being increasingly regarded as a criminal offence., , Social Issues and The Environment, , Chapter6.p65, , 177, , 177, , 4/9/2004, 5:21 PM
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but that this has led to serious floods and loss, of precious soil., , CASE STUDY, Chipko movement, About 300 years ago, a ruler in Rajasthan decided to fell ‘khejri’ trees in his State to create, lime. Local women led by a Bishnoi woman,, Amrita Devi, clung to the trees to prevent the, felling of the trees that formed the basis of, the scarce resources on which they were dependent. The women were ruthlessly massacred. It is said that the ruler later realised his, mistake. The story however has been remembered and was revived in the 1970s when severe tree felling for timber in the Himalayas, prompted local women, supported by people, such as Sunderlalji Bahuguna and Chandi, Prasad Bhat, led a people’s movement to prevent deforestation by timber contractors. They, called their movement the ‘Chipko’ movement, in memory of the event during which women, had clung to their trees and given up their, lives. The movement followed the path the, 300 Bishnoi women had taken three centuries ago in Rajasthan., Chipko is a movement primarily begun and, supported by local women in the hills of, Uttarakhand and Garhwal, where the women, have had to bear the brunt of deforestation., They have not only realised that their fuelwood, and fodder resources have receded away from, their ‘resource use areas’ around their settlements due to commercial timber extraction,, , 6.5.7 The ethical basis of environment education and awareness:, Perhaps the most important concern is related, to creating an ethos that will support a sustainable lifestyle in society. This brings us to the need, for environmental education. The Honorary Supreme Court of our country has thus ordered, that every young individual at school and col-, , The ability of local women to band themselves, together in the foothills of the Himalayas goes, back to the pre Independence days when, women such as Miraben, a disciple of Gandhiji,, moved to this region and understood that it, was the deforestation that led to floods and, devastation of villages in the valleys and in the, Gangetic plains below. They also appreciated, that substitutions of oak and other, broadleaved forests of the Himalayas by planting fast growing pine for timber and resin was, an ecological and social disaster which reduced, the forest resources used by traditional hill, communities., , lege level be exposed to a course on environment. It is not to create only an awareness of, environmental issues, but also to bring about, pro environmental action. Among the variety, of tools that can bring home the ethical issues, of the environment, no solution is as powerful, as real life experiences in nature. Creating a love, for nature brings about strong pro environmental action. Our current educational processes at, Environmental Studies for Undergraduate Courses, , 178, , Chapter6.p65, , Chipko activists have made long padyatras, across the Himalayas protesting against deforestation. The movement has been highly, successful and has been primarily supported, by empowering local women’s groups who, are the most seriously affected segment of, society by deforestation. The movement has, proved to the world that the forests of the, hills are the life support systems of local communities of immense value in terms of local, produce that is essential for the survival of local people and that the forest has less quantifiable but even more important ecological, services such as soil conservation and the maintenance of the natural water regime of the, whole region., , 178, , 4/9/2004, 5:21 PM
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school and college level are being reoriented to, bring this about., , The Gandhian way of life, Mahatma Gandhi had deep insights into the, need to conserve resources. ‘Mans needs but, not his greed can be supported by our earth’, was an important concept that was initiated, by him when people had not realized how, short the world would be of resources in, future. At the time natural resources seemed, to be limitless to most people. This was thus, a new concept and suggested the need for, a uniquely different pattern of living., Gandhiji believed in simplistic living to save, our earth’s resources. He once said that if, India was to become an industrial nation on, the lines of England, the world itself would, be stripped bare of its resources by India’s, people alone., , There are two aspects that are closely connected, with ethical issues that are related to our environment. These are based on valuing nature and, appreciating the beauty of nature and treasuring the magnificence of the wilderness., , Valuing nature as a resource: It is essential that, a value system that is based on environmental, concern becomes a part of the thinking that we, as responsible citizens of our country and our, earth need to bring into our own daily lives., For our ancestors, Nature was considered to be, like a mother. This has been essentially forgotten. In ancient India, forests were considered, sacred. We now know that forests clean up our, air, and act like a sponge that can hold water, for the dry season. In the Hindu scriptures, Buddhist philosophy and especially in the Jain religion, each and every species on earth is, supposed to have a place in the scheme of life., , Education in nature – The Shantiniketan, model, Rabindranath Tagore founded Shantiniketan, and taught an environment-based philosophy. Tagore’s philosophy of education focused attention on the need for a, harmonious association between human, beings and their environment. To achieve this, he relied on exposing young people to nature. This went back to our roots where in, ancient India, learning centers were established in remote forests. Tagore linked these, concepts with celebrations of nature through, music, dance, drama and poetry. At, Shantiniketan, there were celebrations for, each season and ceremonial tree planting., He started Vriksha ropan way back in 1928., In fact much of what was initiated in, Shantiniketan is now accepted as the route, to environment education and sustainable, living and is essentially based on preserving, nature., , Many species were not only valued, but also venerated., In today’s world where many of us are far removed from nature, we need to remind ourselves that everything we use, if tracked back, to its source, has come from nature. We depend on an intact unpolluted world which is, based on nature’s goods and services. No life is, possible without this. If we as citizens begin to, again respect Nature and all its varied species, forming a complex web of life, and appreciate, Nature’s functions and services, it will continue, to support our lives. If we disrespect nature one, cannot expect her to continue to support our, well being. Nature’s resources that we all use, and depend on can only be optimized if they, are equitably shared by all of us. If the disparity, is too great it can only result in anarchy. The, ‘have not’s’ cannot be expected to remain in, , Social Issues and The Environment, , Chapter6.p65, , 179, , 179, , 4/9/2004, 5:21 PM
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abject poverty, making a bare minimum living, from the meager resources they can get, while, the ‘haves’, who are already rich become richer, through unsustainable consumer oriented,, short-term economic development strategies., Bringing back an ethic for nature conservation, requires environment education and conservation awareness. The best way to do so is to expose young people not only to our dependence, on natural resources from the wilderness, but, by bringing about an appreciation of the beauty, and wondrous aspects of nature. This forms a, sharp contrast to the sad plight of degraded, areas and polluted sites in which most of humanity now lives in the developed and developing world., , Appreciating the beauty of Nature and treasuring the magnificence of the Wilderness: We often take Nature for granted. We rarely take the, opportunity to gaze at a scenic sunset, or spend, the time to sit in the incredible silence of the, forest, or listen to the songs of birds and the, sound of the wind rustling through the leaves., Or take the trouble to watch the magic of a, seed germinating from the ground and gradually growing into a seedling over several days., Or observe a tree through a round of seasons, as it gets new leaves, flowers, fruit and seeds., Or reflect on the incredibly large number of linkages between all the different animals and birds, that depend on the seasonal changes in their, habitat. It is the beauty of Nature that gives it, an intrinsic value which we tend to ignore. These, are not mundane day to day events, they are, magical and mystical aspects of nature’s clock, that is ticking silently all around us. They are, part of our living throbbing earth. If we fail to, enjoy these wondrous aspects of Nature our lives, will always remain empty., , or seashore where man’s hand has not made, drastic changes to the ecosystem and one begins to value its beauty. It is there to heal the, human soul and elevate his spirit. Without the, wilderness, the earth would be a sad bleak human dominated landscape. The problem is how, much of the wilderness can we preserve in the, presence of an ever-growing hunger for land, and resources for its utilitarian values. Unless, we begin to see the ecological values of the wilderness, an ethic for its conservation cannot, become part of our daily lives. And without the, wilderness the earth will eventually become, unlivable., The concept of ‘Karma’ is based on a thinking, that the soul moves from man to animal and in, reverse depending on ones actions. This itself, brings about a concept of the oneness of all, forms of life. Ahimsa or non-violence towards, life which includes all plants and animals provides India with its basic philosophy which early, Hindu philosophers and later sages such as Buddha, Mahavir and Mahatma Gandhi spoke of., Buddhist and Jain philosophy is intrinsically woven around non-violence and the great value of, all forms of ‘life’. It brings in the notion that, animals are not to be viewed purely for their, utility value but are a part of the earth’s oneness which is linked with our own lives as well., In Hindu philosophy the earth itself is respected, and venerated. In contrast, in Western thought, Nature is to be subjugated and used. These are, basic differences in thinking processes. Several, modern philosophers in the West have now, begun to see these eastern patterns of thought, as a new basis for human development. This, shift however, from a purely utilitarian or scientific exploitation of Nature, to one of harmony, with Nature, can only occur if each of us loves, and respects nature’s great ‘oneness’., , Once we realise that the wilderness has a value, all its own, this puts man in his rightful role as a, custodian of nature rather than an exploiter. Visit, a wilderness area, a forest, lakeside, waterfall,, Environmental Studies for Undergraduate Courses, , 180, , Chapter6.p65, , 180, , 4/9/2004, 5:21 PM
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6.5.8 The conservation ethic and traditional, value systems of India, In ancient Indian traditions people have always, valued mountains, rivers, forests, trees and several animals. Thus much of nature was venerated and protected. Forests have been, associated with the names of forest gods and, goddesses both in the Hindu religion as well as, in tribal cultures. ‘Tree’ goddesses have been, associated with specific plant species. Ficus, religiosa, the peepal tree, is venerated and is, thus not to be cut down. The Banyan tree in, some regions such as Maharashtra, is venerated, once a year by tying a thread around it as a, symbol of respect. The Tulsi plant is grown on, the doorstep outside every home., Patches of forest have been dedicated to a deity in many Indian cultures especially in tribal, areas. These traditionally protected forest, patches depict the true nature of undisturbed, vegetation and have a large number of indigenous plant species as their exploitation has been, controlled through local sentiments., Certain species of trees have been protected as, they are valued for their fruit or flowers. The, mango tree is protected for its fruit around most, farms even when wood becomes scarce. The, Mohua tree (Madhuca indica) is protected by, tribal people as it provides edible flowers, oil, from its seeds and is used to make a potent, alcohol. Many plants, shrubs and herbs have, been used in Indian medicines which were once, available in the wild in plenty. These are now, rapidly vanishing. Many species of animals are, venerated as being the ‘vahan’ or vehicle of different gods on which they are said to travel, through the cosmos., , invaluable help to Rama during his travels to, Lanka. The Sun god, Surya, rides a horse and, has a superb chariot on which he moves through, the sky. The lion is linked to Durga and the, blackbuck to the moon godess. The cow is associated with Krishna. Vishnu’s incarnations, have been represented as taking various animal, forms which serially include, fish, tortoise, a boar, and a dwarf, and a half man half lion form., The associations to various plants that have been, given a religious significance include Tulsi, which, is linked to Lakshmi and Vishnu. The Tulsi plant, is also linked to the worship of ones own ancestors. The peepal tree is said to be the tree under, which Buddha attained enlightenment. It is also, associated with Vishnu and Krishna. Several trees, are associated with the goddess Laxmi, including Amalaki, Mango and the Tulsi shrub., Traditions also held that these species, which, were considered as an important aspect of Nature, were the basis of local life support systems, and were integral to bringing about a harmonious life. In traditional societies of the past, these, examples were all a part of ethical values that, protected nature. As modern science based on, the exploitation on nature spread into India,, many of these traditions began to lose their effectiveness as measures that led to conserving, nature., Concepts that support nature’s integrity must, thus become a part of our modern educational, systems. This constitutes a key solution to bring, about a new ethic of conserving nature and living sustainable lifestyles., , In Indian mythology, the elephant is associated, with Ganesha. The elephant headed Ganesha, is also linked to the rat. Vishnu is associated with, the eagle. Rama is linked to monkeys. In mythology, Hanuman, the monkey god, rendered, Social Issues and The Environment, , Chapter6.p65, , 181, , 181, , 4/9/2004, 5:21 PM
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6.6 CLIMATE CHANGE, GLOBAL WARMING,, ACID RAIN, OZONE LAYER DEPLETION,, NUCLEAR ACCIDENTS AND HOLOCAUST, 6.6.1 Climate change:, The average temperature in many regions has, been increasing in recent decades. The global, average surface temperature has increased by, 0.6° + 0.2° C over the last century. Globally,, 1998 was the warmest year and the 1990s the, warmest decade on record. Many countries have, experienced increases in rainfall, particularly in, the countries situated in the mid to high latitudes., In some regions, such as parts of Asia and Africa, the frequency and intensity of droughts, have been observed to increase in recent decades. Episodes of El Niño, which creates great, storms, have been more frequent, persistent and, intense since mid-1970s compared with the previous 100 years. All these are signs that the earth, is sick. Its climate is changing, making it more, difficult for mankind to survive. The earth is losing its ability to balance itself due to the imbalances created by human activities., Projections of future climate change are derived, from a series of experiments made by computer, based global climate models. These are worked, out on estimates of aspects such as future population growth and energy use. Climatologists of, the Intergovernmental Panel on Climate Change, (IPCC) have reviewed the results of several experiments in order to estimate changes in climate in the course of this century. These studies, have shown that in the near future, the global, mean surface temperature will rise by 1.4° to, 5.8°C. Warming will be greatest over land areas, and at high latitudes. The projected rate of, warming is greater than has occurred in the last, 10,000 years. The frequency of weather extremes is likely to increase leading to floods or, drought. There will be fewer cold spells but more, heat waves. The frequency and intensity of El, , Human societies will be seriously affected by, extremes of climate such as droughts and floods., A changing climate would bring about changes, in the frequency and/or intensity of these extremes. This is a major concern for human, health. To a large extent, public health depends, on safe drinking water, sufficient food, secure, shelter, and good social conditions. All these, factors are affected by climate change. Fresh, water supplies may be seriously affected, reducing the availability of clean water for drinking, and washing during drought as well as floods., Water can be contaminated and sewage systems may be damaged. The risk of spread of, infectious diseases such as diarrhoeal diseases, will increase. Food production will be seriously, reduced in vulnerable regions directly and also, indirectly through an increase in pests and plant, or animal diseases. The local reduction in food, production would lead to starvation and malnutrition with long-term health consequences,, especially for children. Food and water shortages may lead to conflicts in vulnerable regions,, with serious implications for public health. Climate change related impacts on human health, could lead to displacement of a large number, of people, creating environmental refugees and, lead to further health issues., Changes in climate may affect the distribution, of vector species (e.g. mosquitoes) which in turn, will increase the spread of disease, such as malaria and filariasis, to new areas which lack a, strong public health infrastructure. The seasonal, transmission and distribution of many diseases, Environmental Studies for Undergraduate Courses, , 182, , Chapter6.p65, , Niño is likely to increase. Global mean sea level, is projected to rise by 9 to 88 cm by the year, 2100. More than half of the world’s population, now lives within 60km of the sea. They are likely, to be seriously impacted by an ingress of salt, water and by the rising sea. Some of the most, vulnerable regions are the Nile delta in Egypt,, the Ganges-Brahmaputra delta in Bangladesh,, and many small islands including the Marshall, Islands and the Maldives, (WHO, 2001)., , 182, , 4/9/2004, 5:21 PM
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that are transmitted by mosquitoes (dengue,, yellow fever) and by ticks (Lyme disease, tickborne encephalitis) may spread due to climate, change., , CASE STUDIES, Damage to coral reefs, Pacific, The severity of periodic warming due to El, Nino in 1997 in the Pacific led to the most, serious death in coral ever known. It is estimated that about 10% of the Earth’s coral, reefs were dead, another 30 % were seriously affected and another 30% were degraded., The Global Coral Reef Monitoring Network, Townsville, Australia, has predicted that all, the reefs could be dead by 2050., , Butterfly populations in the United Kingdom, Global warming is leading to an early arrival, of butterflies in Britain. Scientists say that butterflies can now be spotted much earlier every year in the last two decades. Some, like, the red admiral, can now be seen a month, earlier than was the case in the mid – 1970s., Others, like the peacock and the orange tip, are appearing between 15 and 25 days earlier than in the past. Future rise in temperature is likely to have a detrimental effect on, these butterflies. Some butterflies which, need cooler temperatures might suffer., , A Task Group set up by WHO has warned that, climate change may have serious impacts on, human health. Climate change will increase various current health problems, and may also bring, , new and unexpected ones. Strategies aimed at, reducing potential health impacts of anticipated, climate changes should include monitoring of, infectious diseases and disease vectors to detect early changes in the incidence of diseases, and the geographical distribution of vectors; environmental management measures to reduce, risk; disaster preparedness for floods or, droughts; and their health related consequences., It will be necessary to create early warning systems and education for epidemic preparedness., Improved water and air pollution control will, become increasingly essential for human health., Public education will have to be directed at, changes in personal behaviour. Training of researchers and health professionals must become, an essential part of the world becoming more, responsible towards the expected outcome of, Global Climate Change (GCC)., , 6.6.2 Global warming:, About 75% of the solar energy reaching the, Earth is absorbed on the earth’s surface which, increases its temperature. The rest of the heat, radiates back to the atmosphere. Some of the, heat is trapped by greenhouse gases, mostly, carbon dioxide. As carbon dioxide is released by, various human activities, it is rapidly increasing., This is causing global warming., The average surface temperature is about 15°C., This is about 33°C higher than it would be in, the absence of the greenhouse effect. Without, such gases most of the Earth’s surface would, be frozen with a mean air temperature of -18°C., Human activities during the last few decades of, industrialisation and population growth have, polluted the atmosphere to the extent that it, has begun to seriously affect the climate. Carbon dioxide in the atmosphere has increased by, 31% since pre-industrial times, causing more, heat to be trapped in the lower atmosphere., There is evidence to show that carbon dioxide, , Social Issues and The Environment, , Chapter6.p65, , 183, , 183, , 4/9/2004, 5:21 PM
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levels are still increasing. Many countries have, signed a convention to reduce greenhouse gases, under the United Nations Convention on Climate Change. Current international agreements, are however not still effective to prevent the, significant changes in climate and a rise in sea, levels., , industrial activities account for 61% of sulfur, dioxide pollution. Motor vehicle exhaust fumes, are the main source of nitrogen oxides. The acids in acid rain chemically react with any object, they come in contact with. Acids react with other, chemicals by giving up hydrogen atoms., Effects: Acid rain is known to cause widespread, environmental damage., , Global warming is accelerating faster than, what climatologists had calculated a few, years ago. In 1995, the Intergovernmental, Panel on Climate Change predict that global warming would rise temperatures by 3.5, to 10 degrees Centigrade during the 21st, century, if the present trends continue. It is, now believed that this could be much, greater. This would lead to not only temperature changes but in the amount of rainfall. India may see great annual fluctuations, in rainfall leading to floods and drought., , 6.6.3 Acid rain:, When fossil fuels such as coal, oil and natural, gas are burned, chemicals like sulfur dioxide and, nitrogen oxides are produced. These chemicals, react with water and other chemicals in the air, to form sulfuric acid, nitric acid and other harmful pollutants like sulfates and nitrates. These, acid pollutants spread upwards into the atmosphere, and are carried by air currents, to finally, return to the ground in the form of acid rain,, fog or snow. The corrosive nature of acid rain, causes many forms of environmental damage., Acid pollutants also occur as dry particles and, gases, which when washed from the ground by, rain, add to the acids in the rain to form a more, corrosive solution. This is called acid deposition., Damage from acid rain is widespread in North, America, Europe, Japan, China and Southeast, Asia. In the US coal burning power plants contribute to about 70% of sulfur dioxide. In, Canada oil refining, metal smelting and other, , 2. Acid rain indirectly affects plants by removing nutrients from the soil in which they, grow. It affects trees more directly by creating holes in the waxy coating of leaves,, causing brown dead spots which affect the, plant’s photosynthesis. Such trees are also, more vulnerable to insect infestations,, drought and cold. Spruce and fir forests at, higher elevations seem to be most at risk., Farm crops are less affected by acid rain than, forests., 3., , Acid rain that falls or flows as ground water to reach rivers, lakes and wetlands,, causes the water in them to become acidic., This affects plant and animal life in aquatic, ecosystems., , 4. Acid rain also has far reaching effects on, wildlife. By adversely affecting one species,, the entire food chain is disrupted, ultimately, endangering the entire ecosystem. Different aquatic species can tolerate different, levels of acidity. For instance clams and, mayflies have a high mortality when water, has a pH of 6.0, while frogs can tolerate, more acidic water, although with the decline in supply of mayflies, frog populations, may also decline. Land animals that are deEnvironmental Studies for Undergraduate Courses, , 184, , Chapter6.p65, , 1. Acid rain dissolves and washes away nutrients in the soil which are needed by plants., It can also dissolve naturally occurring toxic, substances like aluminium and mercury,, freeing them to pollute water or poison, plants., , 184, , 4/9/2004, 5:21 PM
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pendent on aquatic organisms are also affected., 5. Acid rain and dry acid deposition damages, buildings, automobiles, and other structures, made of stone or metal. The acid corrodes, the materials causing extensive damage and, ruins historic buildings. For instance the, Parthenon in Greece and the Taj Mahal in, India have been affected by acid rain., 6. Although surface water polluted by acid rain, does not directly harm people, the toxic substances leached from soil can pollute water, supply. Fish caught in these waters may be, harmful for human consumption. Acid,, along with other chemicals in the air, produces urban smog, which causes respiratory problems., Solutions: The best way to stop the formation, of acid rain is to reduce the emissions of sulfur, dioxide and nitrogen oxides into the atmosphere. This can be achieved by using less energy from fossil fuels in power plants, vehicles, and industry. Switching to cleaner burning fuels is also a way out. For instance using natural, gas which is cleaner than coal, using coal with, lower sulfur content, and developing more efficient vehicles. If the pollutants have already been, formed by burning fossil fuels, they can be prevented from entering the atmosphere by using, scrubbers in smokestacks in industry. These spray, a mixture of water and limestone into the polluting gases, recapturing the sulfur., In catalytic converters, the gases are passed over, metal coated beads that convert harmful chemicals into less harmful ones. These are used in, cars to reduce the effects of exhaust fumes on, the atmosphere. Once acid rain has affected soil,, powdered limestone can be added to the soil, by a process known as liming to neutralize the, acidity of the soil., , 6.6.4 Ozone layer depletion:, Ozone is formed by the action of sunlight on, oxygen. It forms a layer 20 to 50kms above the, surface of the earth. This action takes place, naturally in the atmosphere, but is very slow., Ozone is a highly poisonous gas with a strong, odour. It is a form of oxygen that has three atoms in each molecule. It is considered a pollutant at ground level and constitutes a health, hazard by causing respiratory ailments like, asthma and bronchitis. It also causes harm to, vegetation and leads to a deterioration of certain materials like plastic and rubber. Ozone in, the upper atmosphere however, is vital to all, life as it protects the earth from the sun’s harmful ultraviolet radiation. The ozone layer in the, upper atmosphere absorbs the sun’s ultraviolet, radiation, preventing it from reaching the earth’s, surface., This layer in the atmosphere protects life on, earth from the dangerous UV radiation from the, sun. In the 1970s, scientists discovered that, chemicals called chlorofluorocarbons or CFCs,, which were used as refrigerants and aerosol, spray propellants, posed a threat to the ozone, layer. The CFC molecules are virtually indestructible until they reach the stratosphere, where, UV radiation breaks them down to release chlorine atoms. The chlorine atoms react with ozone, molecules which break down into oxygen molecules, which do not absorb UV radiations. Since, the early 1980s, scientists detected a thinning, of the ozone layer in the atmosphere above, Antarctica. This phenomenon is now being detected in other places as well including Australia. Although the use of CFCs has been reduced, and now banned in most countries, other chemicals and industrial compounds such as bromine,, halocarbons and nitrous oxides from fertilizers, may also attack the ozone layer., The destruction of the ozone layer is seen to, cause increased cases of skin cancer and cataracts. It also causes damage to certain crops and, , Social Issues and The Environment, , Chapter6.p65, , 185, , 185, , 4/9/2004, 5:21 PM
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to plankton, thus affecting natures food chains, and food webs. This in turn causes an increase, in carbon dioxide due to the decrease in vegetation., With the signing of the Montreal Protocol in, 1987, a treaty for the protection of the ozone, layer, the use of CFCs was to be banned by the, year 2000. After 2000, the ozone layer is expected to recover slowly over a period of about, 50 years., , 6.6.5 Nuclear Accidents and Nuclear Holocaust:, Nuclear energy was researched and discovered, by man as a source of alternate energy which, would be clean and cheap compared to fossil, fuels. And although this did happen, along with, the benefits of nuclear energy came its downfalls. In the short history of nuclear energy there, have been accidents that have surpassed any, natural calamity or other energy source extraction in their impacts. A single nuclear accident, can cause loss of life, long-term illness and destruction of property on a large scale for a long, period of time. Radioactivity and radioactive fallout leads to cancer, genetic disorders and death, in the affected area for decades after, thus affecting all forms of life for generations to come., , CASE STUDY, Nuclear disasters and leakages, In 1986 the Nuclear Power Station at, Chernobyl in USSR developed a problem that, led to a fire and a number of explosions in, its Nuclear Reactor. The radioactive dust, spread over many kilometers and covered, not only Europe but North America as well., Three people died in the explosion and 28, shortly after due to radiation exposure. Some, 259 sick were hospitalized. As the area had, to be evacuated 1,35,000 people had to be, moved immediately and another 1.5 lac by, 1991. As radioactive fall out continued even, more people had to be moved. An estimated, 6.5 lakh people may have been seriously affected. They may get cancer, thyroid, tumours, and cataracts, and suffer from a, lowered immune mechanism., As radioactivity passes from grass to herbivores, sheep in Scotland and Reindeer in, Lapland were affected and were unfit for, human consumption. Vegetable, fruit and, milk were contaminated in Europe., A French Nuclear Waste Processing Center, in Normandy may have affected the lives of, children playing nearby. They may develop, leukemia (blood cancer) in later life., , Nuclear holocaust:, The use of nuclear energy in war has had devastating effects on man and earth. The, Hiroshima and Nagasaki incident during World, War II, the only use of nuclear power in war in, history, is one of the worst disasters in history., In 1945, the United States dropped atomic, bombs in Japan over the towns of Hiroshima, and Nagasaki. These two atomic bombs killed, thousands of people, left many thousands injured and devastated everything for miles, Environmental Studies for Undergraduate Courses, , 186, , Chapter6.p65, , 186, , 4/9/2004, 5:21 PM
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around. The effects of the radiation from these, nuclear bombs can still be seen today in the form, of cancer and genetic mutations in the affected, children and survivors of the incident., , 6.7 WASTELAND RECLAMATION, Loss of vegetation cover leads to loss of soil, through erosion, which ultimately creates wastelands. This is one of the pressing problems of, the country. Loss of soil has already ruined a, large amount of cultivable land in our country., If it remains unchecked, it will affect the remaining land. Unless we adequately safeguard our, ‘good’ lands, we may eventually face a serious, shortage of food grains, vegetables, fruit, fodder and fuel wood. Hence, conservation of soil,, protecting the existing cultivable land and reclaiming the already depleted wastelands figures prominently among the priority tasks of, planning for the future. Some of the wasteland, reclamation programs have been unsuccessful, because after sometime the land reverts to its, original poor condition due to mismanagement, and unscientific ways in which the reclamation, has been carried out., In choosing wasteland reclamation methods attention must be paid to the cost factor. This has, to be taken into account before deciding on a, particular method for reclamation of wastelands., A proper study of environmental aspects and, human impacts which are responsible for the, development of wastelands have to be looked, into., Wasteland can be classified into three forms:, (1) Easily reclaimable, (2) Reclaimable with, some difficulty, (3) Reclaimable with extreme difficulty., Easily reclaimable wastelands can be used for, agricultural purposes. Those which can be reclaimed with some difficulty can be utilized for, agro forestry. Wastelands that are reclaimed, , with extreme difficulty can be used for forestry, or to recreate natural ecosystems., Agriculture: Wasteland can be reclaimed for, agriculture by reducing the salt content which, can be done by leaching and flushing. Gypsum,, urea, potash and compost are added before, planting crops in such areas., Agro forestry: This involves putting land to multiple uses. Its main purpose is to have trees and, crops inter- and /or under planted to form an, integrated system of biological production within, a certain area. Thus, agro forestry implies integration of trees with agricultural crops or livestock management simultaneously., Forestry: Attempts to grow trees in highly non, alkaline saline soils have been largely unsuccessful. Field experiments have shown that species, like Eucalyptus, Prosopis and Acacia Nilotica, could not be grown in highly alkaline soil. Studies have shown that if tree seedlings are planted, with a mixture of original soil, Gypsum, and, manure, better growth can be achieved. It is, however important to use indigenous species, of trees so that the program recreates the local, ecosystem with all its species., , Need for wasteland development:, Wasteland development provides a source of, income for the rural poor. It ensures a constant, supply of fuel, fodder and timber for local use., It makes the soil fertile by preventing soil erosion and conserving moisture. The program, helps maintain an ecological balance in the area., The increasing forest cover helps in maintaining, local climatic conditions. Regenerated vegetation cover helps in attracting birds which feed, on pests in the surrounding fields and function, as natural pest controllers. The trees help in holding back moisture and reduce surface run off, rates thus helping in the control of soil erosion., , Social Issues and The Environment, , Chapter6.p65, , 187, , 187, , 4/9/2004, 5:21 PM
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Components of wasteland reclamation:, The first major task is the identification of the, problem at the micro level. For this it is necessary to have District, Village and plot level surveys of the wasteland. A profile of the maps, indicating the detailed distribution and information on the wasteland is essential. With the help, of local government institutions such as the village Panchayats, along with Block Development, Officers, Revenue Department functionaries, a, plan based on the community needs must be, produced. This must be done through a participatory exercise that involves all the different, stakeholders in the community. A think-tank of, administrators, ecologists, and local NGOs must, also be involved in the process., , velopment provide the local people with newer, technological advances. Guidelines regarding, control of water logging must be provided. Appropriate technologies must be made available, to people belonging to the weaker sections and, landless farmers. Collective efforts have to be, made to check soil losses through water and, wind erosion to prevent the collapse of the irrigation system through siltation. Plans concerning wasteland reclamation and utilization, prepared at various stages must be properly integrated for a successful long-term outcome., , CASE STUDY, Tehri, Uttar Pradesh, , The next step is to identify the factors that are, responsible for the formation of wastelands., Based on these factors the wasteland is classified into: marginally, partially or severely deteriorated lands. Locale specific strategies for, reclaiming the wasteland must be worked out., Government officials along with the local NGOs, must assist the farmers by demonstrating improved methods of cultivation, arranging for, loans for the small, marginal and landless farmers and the people from the weaker sections of, the society. Involving local women has proved, to be of great value. Another essential component of the program is to organize publicity campaigns, integrated with training farmers and, frontline Government and Forest Department, staff on the various aspects of wasteland utilization. Environmental scientists can help by suggesting the necessary changes in cropping, patterns particularly for drought prone areas., Other tasks that should be addressed include, the selection of appropriate crops for fodder and, trees that provide local people with non-wooded, forest products according to the nature of the, wasteland. Testing soil in laboratories provides, guidance to the farmers on the proper land, management to be used. Irrigation and other, expertise needed for improving productivity, without creating unsustainable patterns of de-, , Environmental Studies for Undergraduate Courses, , 188, , Chapter6.p65, , Nagchaund village in Tehri District of Uttar, Pradesh was once an eroded and deforested, land. When Soban Singh Bhandari returned, to his village after retirement from the army, in 1987 he was struck by this degradation., After six months he became the pradhan of, the village and decided to implement various village development schemes differently., Through the Jawahar Rozgar Yojana, he, gained immense community support. In, 1990 the Forest Department selected a 30hectare barren piece of community land for, a micro-watershed development program., The villagers controlled grazing in the area,, undertook plantations for fuel and fodder., Bhandari helped the village raise money by, selling the fodder from the area to a neighboring village and the money was used for, development and maintenance work. This, community effort has had a great impact on, the ecology of the area. The moisture content of the area increased and the water, sources of the villages were recharged. Local people now have access to all the natural resources they need for their daily lives., , 188, , 4/9/2004, 5:21 PM
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The demands of our increasing human population for environmental goods and services has, imposed severe pressures on the available land, resources especially on the forests and green, cover. This is closely linked to the wellbeing of, the rural population which constitutes a large, percent of the population which depends on, local natural resources for their survival. The increasing demand for food, fodder, fuel wood,, etc. has led to activities that are responsible for, increasing environmental degradation. This is responsible for the extension of wastelands. Thus, the development of agro forestry based agriculture and forestry has become the prime prerequisite for an overall development of the, economy in the country. The pressure on land is, already very high and the only hope of increasing productivity lies in bringing appropriate improvement in the various categories of, wasteland spread over the country., , 6.8 CONSUMERISM AND WASTE PRODUCTS, Modern societies that are based on using large, amounts of goods, especially those that are, manufactured for one time use, are extremely, wasteful. The increasing consumption of natural resources has lead to serious environmental, problems around the world. Current consumption patterns are depleting non-renewable resources, poisoning and degrading ecosystems,, and altering the natural processes on which life, depends. The present pattern of consumption,, especially in affluent societies, is mainly responsible for the high level of utilization of resources., People in the industrialized countries make up, 20% of the world population but consume 80%, of the world’s resources and produce 80% of, wastes. This is due to a pattern of economic, development that ensures that people go on, consuming even more than they actually need., India is rapidly moving into this unsustainable, pattern of economic growth and development., The rich in such a society get richer often at the, cost of the poor whose lives are not improved, , by the process of development. It is seen that, today’s consumption patterns are depleting, natural resources at a rapid rate and widening, the inequalities in consumption in different societies. Consumerism causes wasteful use of energy and material far beyond that needed for, everyday living at a comfortable level. Money is, not the only way to measure the cost of an item, that we use. When one adds up all the raw, material and energy that goes into the manufacture of goods or the services provided by, nature that one uses during a day’s activities,, the toll on the environment is large. When this, cost is multiplied over a lifespan, the amount is, staggering. If one considered the overutilisation, in each family, city or a country, the impacts are, incredibly high. For example: two hundred billion cans, bottles, plastic cartons and paper cups,, are thrown away each year in the “developed”, world. “Disposable” items greatly increase this, waste. Rather than compete on quality or reliability, many industrial consumer products are, made for one-time use. Buying quality products, that are warranteed against failure or wearing, out, learning about the raw materials that things, are made of, and an appreciation of their origin, from nature’s storehouse, as well as knowing, the conditions of the workers that make them,, are some ways of resisting consumerism and, decreasing waste., , CASE STUDY, Himachal Pradesh was the first State in India, to regulate the manufacture and use of plastics. The State proposed a ban on all types, of polythene packing., , While there may be some new appliances and, cars that are more productive and energy efficient, discarding the old often leads to an almost total waste of the energy and material, already invested in these products. This alone, , Social Issues and The Environment, , Chapter6.p65, , 189, , 189, , 4/9/2004, 5:21 PM
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may more than nullify the energy savings of the, new product. This is a tricky problem., Consumerism is related to the constant purchasing of new goods, with little attention to their, true need, durability, product origin, or the environmental consequences of their manufacture, and disposal. Consumerism is driven by huge, sums spent on advertising designed to create, both a desire to follow trends, and a personal, feeling of satisfaction based on acquisition., Materialism is one of the end results of consumerism., Consumerism interferes with the sustainable use, of resources in a society by replacing the normal common sense desire for an adequate supply of life’s necessities, with an insatiable quest, for things that are purchased by larger and larger, incomes to buy them. There is little regard for, the true utility of what is bought. An intended, consequence of this strategy which is promoted, by those who profit from consumerism, is to, accelerate the discarding of the old, either because of lack of durability or a change in fashion. Especially in developed countries, landfills, are being rapidly filled with cheap discarded, products that fail to work within a short time, and cannot be repaired. In many cases consumer, products are made psychologically obsolete by, the advertising industry long before they actually wear out., The inordinate amount of waste that is generated by consumer-oriented societies around the, world is now a serious environmental issue. Most, human activities are related to production and, consumption cycles which produce excessive, amounts of waste in the form of solid, liquid, and gaseous waste products. The problems of, waste management in the urban and rural sectors are different. Rural communities that were, smaller, once had a limited amount of waste, which was recycled as the communities used, them effectively. With the advent of an industrial civilization the highly complex technologi-, , The increasing demands of consumption on the, finite resources of the planet, increasing level, of environmental pollution, and the problems, of waste disposal must be changed to the careful utilization of resources, recovery of used, material by waste recycling. Therefore reuse of, goods and waste utilization should become a, part of the production -consumption cycle. Utilizing various forms of waste must be made a, part of the planning and development process., Current patters in the industrial sector have led, to the disposal of waste in a careless uneconomical manner. Burning or dumping wastes, into streams and oceans, or creating more landfills damages the environment. For example it is, estimated that the per capita production of domestic waste is many times higher in a developed country when compared to a developing, country. Unfortunately, many developing countries are now working out similar wasteful trends, through development, but do not have the same, economic potential to handle the waste this new, unsustainable strategy produces. Large quantities of solid, liquid and gaseous waste is produced by urban industrial communities in the, form of plastic, paper, leather, tin cans, bottles,, mineral refuse, and pathological waste from, hospitals. Dead animals, agricultural wastes,, fertilizer and pesticide overuse, and human and, Environmental Studies for Undergraduate Courses, , 190, , Chapter6.p65, , cal processes for production of goods has rapidly increased problems due to inadequate waste, disposal. This creates a heavy burden on natural resources, degrades the environment and creates health hazards. With the rapid increase in, population, the amount of waste in terms of, quantity and quality has increased waste management pressures many fold in recent years. If, the high quantities of waste generated continues, mankind will be drowned under heaps of, garbage, and streams of sewage. His health will, be affected by dangerous industrial effluents,, and he will be smothered by clouds of smoke, and unhealthy gases. Human civilisation will run, out of resources, preventing further development., , 190, , 4/9/2004, 5:21 PM
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animal excreta are essentially rural concerns. The, waste is either discharged into the atmosphere,, into water sources, or buried underground., These wastes are not considered to have any, economic value. This attitude towards waste has, led to disastrous effects on the environment, besides over exploiting natural resources., , Bagasse, a waste product of the sugar industry,, is used in the paper, ply industries., The material left over after extraction of oil from, seeds is used as cattle feed., , CASE STUDY, Reduce, reuse, recycle, Reduce, Reuse, Recycle, or the 3Rs principle, is, the new concept in waste management. But, what does it actually mean? Although some, waste is inevitable in any society, we must minimize the generation of waste at the source by, using minimal resources. Do not use what you, do not need. The goal of every society should, be to reach a low-waste or no waste society., Eg. Fancy packaging of consumer products in, two or three layers is not necessary., Use your own reusable cloth/ jute bags instead, of plastic bags., The residual waste can be converted into a, useable resource. In developed countries waste, is used to produce energy., Several technological breakthroughs have recently been made to recover material from industrial waste such as heavy metals and, chemicals such as mercury and nitric acid. Thus, the waste does not remain a waste product anymore, but becomes a useful resource., Eg. Using kitchen wet waste to make compost, that can be used as an organic fertilizer., , Plastic to oil, The Indian Oil Corporation Limited and the, Department of Science and Technology are, expected to establish India’s first plant to, convert waste plastic into petrol, diesel and, LPG., , The generated waste or discarded material that, cannot be used again in its original form can be, sent back to the industry to be broken down, and used as a resource to be made into a new, product of the same type or into something, entirely different., Eg. Plastic items are recycled into new plastic, products., Metal scrap and broken glass is used to make, new metal products., Finally, the waste material generated which can, neither be reused or recycled, must be disposed, off in a proper manner with minimum impact, to the environment., -, , Non toxic solid waste should be properly, segregated and disposed off in landfills that, are properly sealed to avoid leakage and, contamination of surrounding land and, groundwater., , -, , Toxic wastes should be treated or disposed, off separately in a proper manner., , Using sewage in a biogas plant to make fuel., One industry’s waste could be a valuable resource for another industry., Eg. Cloth rags from the textile industry are, bought and used by paper and other industries., Social Issues and The Environment, , Chapter6.p65, , 191, , 191, , 4/9/2004, 5:21 PM
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-, , Sewage and industrial wastewater should, be adequately treated and raw materials recovered from it where possible before it is, released into our rivers and waterways., , The 3R principle of Reduce, Reuse, Recycle,, should be followed in that order., -, , -, , -, , Reduction is the best option. If we reduce, at source, there is a smaller chance of waste, generation and the pressure on our already, stretched natural resources is reduced., Reuse is the next best option, as the product is reused in its current form without any, energy expended to convert it into a new, item., Recycling is the last option, as although it, converts a waste into a resource, it uses, energy to transform that resource into a, new useable product., , Thus by following the ‘Reduce, Reuse, Recycle’, principle, i.e. by reducing use at source, by reusing and recycling whatever possible and finally by proper disposal of residual waste, we, can cut down or the waste generated and ensure that the minimal residual waste does not, harm our environment. This principle can be, followed by everyone, from an individual or an, industry to a whole country., What can I do? You can follow the 3Rs principle in the following ways:, , 1. Use only as much as you need, be it any resource – water, food, paper, etc., 2. Next time you throw away something, think, about whether it is really a waste. If it is of no, use to you, could someone else use it?, Reuse rinse water to water your garden, etc., Donate old clothes to the needy, instead of, throwing them away., 3. If you are sure the item is not usable in its, present form, can it be recycled? Paper, plastics, glass, metal can all be recycled., 4. Segregate your waste into wet and dry garbage. Wet garbage includes most kitchen, wastes. Most of this can be used for composting., Most dry garbage is recyclable., The amount of dry waste generated in your, household is an indicator of how well you are, following the 3Rs principle. A lot of dry waste, means you should go back to the ‘Reduce and, Reuse’ principles and try to follow them better., 5. Avoid the use of non-biodegradable materials such as Styrofoam and certain types of plastics., Although most plastics are recyclable, recycling, still takes up energy, which is another precious, resource not to be wasted. If thrown away as, waste, Styrofoam and plastics can take hundreds, of years to decompose., 6. Do not litter or throw garbage in public places., Garbage and litter is a visual contaminant and, can cause diseases health problems. Proper disposal of garbage is an important part of waste, management., 7. Be a conscious consumer and do not buy products that are over packaged. Try choosing products that are made from recycled material or, are organically grown., Environmental Studies for Undergraduate Courses, , 192, , Chapter6.p65, , 192, , 4/9/2004, 5:21 PM
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Suggestions for better waste management:, 1) Every country must survey all the different forms of waste generation along, with its sources. They must set up priorities concerning waste utilization., Most waste can be converted to resources which can enhance the, economy of the country., 2) Plans should be prepared for controlling waste at the source. This must include segregation of wet and dry waste,, where the wet waste can be converted, to compost and used and the dry waste, is recycled., 3) Research and developmental programs, to find innovative methods of waste recycling must be encouraged. Recycling, should be a part of conservation and, environmental protection programs. Private and public organizations for waste, recycling and management should be, set up., 4) Uneconomical methods of waste disposal like land filling, or incineration, must be reduced to a minimum. Plans, for appropriate disposal of non-utilizable, hazardous waste from chemical industries must be implemented and strictly, monitored., 5) Every community should organize extensive programs on education and demonstration on the reduction of waste,, and the proper disposal and effective, reutilization of waste material. People, should be informed of the need for, waste management to protect the quality of the environment. This should be, included in the curriculum at school and, college level., 6) Every society should make efforts to design peoples’ life styles and cultural patterns based on low waste production., The goal of every society should be to, reach a low-waste or no waste society., , Resources must be conserved by proper selection, production technologies, recovering and, recycling what is usable and reducing unnecessary demands for consumption and inventing, technologies which would make it possible for, reusing the waste resources so as to reduce overexploiting of our existing resources., , 6.9 THE ENVIRONMENT (PROTECTION) ACT, The Environment (Protection) Act, 1986 not only, has important constitutional implications but, also an international background. The spirit of, the proclamation adopted by the United Nations, Conference on Human Environment which took, place in Stockholm in June 1972, was implemented by the Government of India by creating, this Act., Although there were several existing laws that, dealt directly or indirectly with environmental, issues it was necessary to have a general legislation for environmental protection because the, existing laws focused on very specific types of, pollution, or specific categories of hazardous, substances or were indirectly related to the environment through laws that control landuse,, protect our National Parks and Sanctuaries and, our wildlife. However there were no overarching, legislation and certain areas of environmental, hazards were not covered. There were also gaps, in areas that were potential environmental hazards and there were several inadequate linkages, in handling matters of industrial and environmental safety. This was essentially related to the, multiplicity of regulatory agencies. Thus there, was a need for an authority which could assume, the lead role for studying, planning and implementing long term requirements of environmental safety and give directions to, as well as, coordinate a system of speedy and adequate, response to emergency situations threatening, the environment., , Social Issues and The Environment, , Chapter6.p65, , 193, , 193, , 4/9/2004, 5:21 PM
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This Act was thus passed to protect the environment, as there was a growing concern over, the deteriorating state of the environment. As, impacts grew considerably environmental protection became a national priority in the 1970s., The decline in the environmental quality, was, evidenced by increasing pollution, loss of forest, cover and an increasing threat to biodiversity., The presence of excessive concentrations of, harmful chemicals in the atmosphere and, aquatic ecosystems leads to the disruption of, food chains and a loss of species. These are, symptoms of a rapidly deteriorating environment. The growing risks of environmental accidents and threats to life support systems now, looms threateningly over our civilisation. The decision taken at the conference in Stockholm, strongly voiced these environmental concerns, and several measures were made possible for, environmental protection. While the need for a, wider general legislation to protect our environment is now in place, it has become increasingly evident that our environmental situation, continues to deteriorate. We need to implement, this Act much more aggressively if our environment is to be protected., Public concern and support is crucial for implementing the EPA. This must be supported by an, enlightened media, good administrators, highly, aware policy makers, informed judiciary and, trained technocrats who together can influence, and prevent further degradation of our environment. Each of us has a responsibility to make, this happen., , 6.10 THE AIR (PREVENTION AND CONTROL, OF POLLUTION) ACT, The Government passed this Act in 1981 to clean, up our air by controlling pollution. Sources of, air pollution such as industry, vehicles, power, plants, etc. are not permitted to release particulate matter, lead, carbon monoxide, sulfur, , This Act is created ‘to take appropriate steps, for the preservation of the natural resources of, the earth which among other things includes, the preservation of high quality air and ensures, controlling the level of air pollution., The main objectives of the Act are as follows:, (a) To provide for the Prevention, Control and, abatement of air pollution., (b) To provide for the establishment of Central, and State Boards with a view to implement, the Act., (c) To confer on the Boards the powers to, implement the provisions of the Act and, assign to the Boards functions relating to, pollution., Air pollution is more acute in heavily industrialized and urbanized areas, which are also densely, populated. The presence of pollution beyond, certain limits due to various pollutants discharged through industrial emission are monitored by the Pollution Control Boards set up in, every State., Environmental Studies for Undergraduate Courses, , 194, , Chapter6.p65, , dioxide, nitrogen oxide, volatile organic compounds (VOCs) or other toxic substances beyond, a prescribed level. To ensure this, Pollution Control Boards (PCBs) have been set up by Government to measure pollution levels in the, atmosphere and at certain sources by testing, the air. This is measured in parts per million or, in milligrams or micrograms per cubic meter. The, particulate matter and gases that are released, by industry and by cars, buses and two wheelers is measured by using air sampling equipment., However, the most important aspect is for, people themselves to appreciate the dangers of, air pollution and reduce their own potential as, polluters by seeing that their own vehicles or, the industry they work in reduces levels of emissions., , 194, , 4/9/2004, 5:21 PM
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Powers and Functions of the Boards, Central Board: The main function of the Central Board is to implement legislation created to, improve the quality of air and to prevent and, control air pollution in the country. The Board, advises the Central Government on matters concerning the improvement of air quality and also, coordinates activities, provides technical assistance and guidance to State Boards and lays, down standards for the quality of air. It collects, and disseminates information in respect of matters relating to air pollution and performs functions as prescribed in the Act., State Pollution Control Boards: The State Boards, have the power to advice the State Government, on any matter concerning the prevention and, control of air pollution. They have the right to, inspect at all reasonable times any control equipment, industrial plant, or manufacturing process, and give orders to take the necessary steps to, control pollution. They are expected to inspect, air pollution control areas at intervals or whenever necessary. They are empowered to provide, standards for emissions to be laid down for different industrial plants with regard to quantity, and composition of emission of air pollutants, into the atmosphere. A State Board may establish or recognize a laboratory to perform this, function., The State Governments have been given powers to declare air pollution control areas after, consulting with the State Board and also give, instructions for ensuring standards of emission, from automobiles and restriction on use of certain industrial plants., Penalties: Persons managing industry are to be, penalized if they produce emissions of air pollutants in excess of the standards laid down by, the State Board. The Board also makes applications to the court for restraining persons causing air pollution., , Whoever contravenes any of the provision of, the Act or any order or direction issued is punishable with imprisonment for a term which may, extend to three months or with a fine of, Rs.10,000 or with both ,and in case of continuing offence with an additional fine which may, extend to Rs 5,000 for every day during which, such contravention continues after conviction, for the first contravention., What can an individual do to control air pollution?, 1) When you see a polluting vehicle take down, the number and send a letter to the Road, Transport Office (RTO) and the Pollution, Control Board (PCB)., 2) If you observe an industry polluting air, inform the Pollution Control Board in writing, and ascertain if action is taken., 3) Use cars only when absolutely necessary., Walk or cycle as much as possible instead, of using fossil fuel powered vehicles., 4) Use public transport as far as possible, as, more people can travel in a single large vehicle rather than using multiple small vehicles which add to pollution., 5) Share a vehicle space with relatives and, friends. Carpools minimise the use of fossil, fuels., 6) Do not use air fresheners and other aerosols and sprays which contain CFCs that deplete the ozone layer., 7) Do not smoke in a public place. It is illegal, and endangers not only your own health, but also that of others., 8) Coughing can spread bacteria and viruses., Use a handkerchief to prevent droplet in-, , Social Issues and The Environment, , Chapter6.p65, , 195, , 195, , 4/9/2004, 5:21 PM
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fection which is air borne. It endangers the, health of other people., It is a citizen’s duty to report to the local authorities such as the Collector or the Pollution, Control Board, and the press about offences, made by a polluter so that action can be taken, against the offender. It is equally important to, prevent and report to the authorities on cutting, down of trees, as this reduces nature’s ability to, maintain the carbon dioxide and oxygen levels., preventing air pollution and preserving the quality of our air is a responsibility that each individual must support so that we can breathe air, that will not destroy our health., , 6.11 THE WATER (PREVENTION AND CONTROL OF POLLUTION) ACT, The Government has formulated this Act in 1974, to be able to prevent pollution of water by industrial, agricultural and household wastewater that can contaminate our water sources., Wastewater with high levels of pollutants that, enter wetlands, rivers, lakes, wells as well as the, sea are serious health hazards. Controlling the, point sources by monitoring levels of different, pollutants is one way to prevent pollution by, giving a punishment to a polluter. However it is, also the responsibility of people in general to, inform the relevant authority when they see a, likely source of pollution. Individuals can also, do several things to reduce water pollution such, as using biodegradable chemicals for household, use, reducing use of pesticides in gardens, and, identifying polluting sources at workplaces and, in industrial units where oil or other petroleum, products and heavy metals are used. Excessive, organic matter, sediments and infecting organisms from hospital wastes can also pollute our, water. Citizens need to develop a watchdog, force to inform authorities to take appropriate, actions against different types of water pollution. A polluter must pay for his actions. How-, , The main objectives of the Water Act are to provide for prevention, control and abatement of, water pollution and the maintenance or restoration of the wholesomeness of water. It is designed to assess pollution levels and punish, polluters. The Central Government and State, Governments have set up Pollution Control, Boards that monitor water pollution., , Functions of the Pollution Control Boards:, The Government has given the necessary powers to the PCBs to deal with the problems of, water pollution in the country. The Government, has also suggested penalties for violation of the, provisions of the Act., Central and State water testing laboratories, have been set up to enable the Boards to assess, the extent of water pollution and standards have, been laid down to establish guilt and default., The Central and State Boards are entitled to, certain powers and functions which are as follows:, Central Board: It has the power to advise the, Central Government on any matters concerning the prevention and control of water pollution. The Board coordinates the activities of the, State Boards and also resolves disputes. The, Central Board can provide technical assistance, and guidelines to State Boards to carry out investigations and research relating to water pollution, and organizes training for people involved, in the process. The Board organizes a comprehensive awareness program on water pollution, through mass media and also publishes data, regarding water pollution. The Board lays down, or modifies the rules in consultation with the, State Boards on standards of disposal of waste., Environmental Studies for Undergraduate Courses, , 196, , Chapter6.p65, , ever, preventing pollution is better than trying, to cure the problems it has created, or punishing offenders., , 196, , 4/9/2004, 5:21 PM
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The main function of the Central Board is to, promote the cleanliness of rivers lakes streams, and wells in the country., State Boards: They have the power to advise, the State Government on any matters concerning water pollution. It plans a comprehensive, program for the prevention of water pollution., It collects and disseminates information on water pollution and participates in research in collaboration with the Central Board in organizing, training of people involved in the process. The, Board inspects sewage or trade effluents, treatment plants, purification plants and the systems, of disposal and also evolves economical and reliable methods of treatment of sewage and other, effluents. It plans the utilization of sewage water for agriculture. It ensures that if effluents, are to be discharged on land the waste is diluted. The State Board advises State Governments with respect to location of industries., Laboratories have been established to enable, the Board to perform its functions., The State Boards have the power to obtain information from officers empowered by it who, make surveys, keep records of flow, volume, and, other characteristics of the water. They are given, the power to take samples of effluents and suggest the procedures to be followed in connection with the samples. The concerned board, analyst is expected to analyze the sample sent, to him and submit a report of the result to the, concerned Board. The Board is required to send, a copy of the result to the respective industry., The Board also has the power of inspecting any, plant record, register, document or any material object, and can conduct a search in any place, in which there is reason to believe that an offence has been conducted under the Act., Penalties are charged for acts that have caused, pollution. This includes failing to furnish information required by the Board, or failing to inform the occurrence of any accident or other, unforeseen act. An individual or organisation, , that fails to comply with the directions given in, the subsections of the law can be convicted or, punished with imprisonment for a term of three, months or with a fine of Rs10,000 or both and, in case failure continues an additional fine of, Rs.5,000 everyday. If a person who has already, been convicted for any offence is found guilty, of the same offence again, he/she after the second and every subsequent conviction, would be, punishable with imprisonment for a term not, less than two years but which may extend to, seven years with fine., What can individuals do to prevent water pollution?, 1. Inform the Pollution Control Board of any, offender who is polluting water and ensure, that appropriate action is taken. One can, also write to the press., 2. Do not dump wastes into a household or, industrial drain which can directly enter any, water body, such as a stream, river, pond,, lake or the sea., 3. Do not use toilets for flushing down waste, items as they do not disappear but reappear at other places and cause water pollution., 4. Use compost instead of chemical fertilizers, in gardens., 5. Avoid use of pesticides at home like DDT,, Melathion, Aldrin, and use alternative methods like paste of boric acid mixed with gram, flour to kill cockroaches and other insects., Use dried neem leaves to help keep away, insects., , 6.12 THE WILDLIFE PROTECTION ACT, This Act passed in 1972, deals with the declaration of National Parks and Wildlife Sanctuaries, , Social Issues and The Environment, , Chapter6.p65, , 197, , 197, , 4/9/2004, 5:21 PM
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and their notification. It establishes the structure of the State’s wildlife management and the, posts designated for Wildlife Management. It, provides for setting up Wildlife Advisory Boards., It prohibits hunting of all animals specified in, Schedules I to IV of the Act. These are notified, in order of their endangeredness. Plants that are, protected are included in schedule VI., The Amendment to the Wildlife Protection Act, in 2002 is more stringent and prevents the commercial use of resources by local people. It has, brought in new concepts such as the creation, of Community Reserves. It has also altered several definitions. For instance in animals, fish are, now included. Forest produce has been redefined to ensure protection of ecosystems., While there are several changes, the new Act, still has serious issues concerned with its implementation. Laws are only as good as the ones, that can be complied with. The Act is expected, to deter people from breaking the law. However, there are serious problems due to poaching. One cannot expect to use the Act to reduce, this without increasing Forest Staff, providing, weapons, jeeps, radio equipment, etc. for establishing a strong deterrent force., Penalties: A person who breaks any of the conditions of any license or permit granted under, this Act shall be guilty of an offence against this, Act. The offence is punishable with imprisonment for a term which may extend to three years, or with a fine of Rs 25,000 or with both. An, offence committed in relation to any animal, specified in Schedule I, or Part II of Schedule II,, like the use of meat of any such animal, or animal articles like a trophy, shall be punishable, with imprisonment for a term not less than one, year and may extend to six years and a fine of, Rs 25,000., In the case of a second or subsequent offence, of the same nature mentioned in this sub-section, the term of imprisonment may extend to, , What can an individual do?, 1) If you observe an act of poaching, or see a, poached animal, inform the local Forest Department Official at the highest possible, level. One can also report the event through, the press. Follow up to check that action is, taken by the concerned authority. If no action is taken, one must take it up to the, Chief Wildlife Warden of the State., 2) Say ‘no’ to the use of wildlife products and, also try to convince other people not to buy, them., 3) Reduce the use of wood and wood products wherever possible., 4) Avoid misuse of paper because it is made, from bamboo and wood, which destroys, wildlife habitat. Paper and envelopes can, always be reused., 5) Create a pressure group and ask Government to ensure that the biodiversity of our, country is conserved., 6) Do not harm animals. Stop others from inflicting cruelty to animals., 7) Do not disturb birds nests and fledglings., 8) When you visit the Zoo do not tease the, animals by throwing stones or feeding, them, and prevent others from doing so., 9) If you come across an injured animal do, what you can to help it., 10) If the animal needs medical care and expert attention contact the Society for the, Prevention of Cruelty to Animals in your city., Environmental Studies for Undergraduate Courses, , 198, , Chapter6.p65, , six years and not less than two years with a penalty of Rs.10,000., , 198, , 4/9/2004, 5:21 PM
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11) Create awareness about biodiversity conservation in your own way to family and, friends., 12) Join organizations, which are concerned, with protection of biodiversity, such as, Worldwide Fund For Nature –India (WWFI), Bombay Natural History Society (BNHS),, or a local conservation NGO., , 6.13 FOREST CONSERVATION ACT, To appreciate the importance of the Forest Conservation Act of 1980, which was amended in, 1988, it is essential to understand its historical, background. The Indian Forest Act of 1927 consolidated all the previous laws regarding forests, that were passed before the 1920’s. The Act, gave the Government and Forest Department, the power to create Reserved Forests, and the, right to use Reserved Forests for Government, use alone. It also created Protected Forests, in, which the use of resources by local people was, controlled. Some forests were also to be controlled by a village community, and these were, called Village Forests., The Act remained in force till the 1980s when it, was realised that protecting forests for timber, production alone was not acceptable. The other, values of protecting the services that forests, provide and its valuable assets such as, biodiversity began to overshadow the importance of their revenue earnings from timber., Thus a new Act was essential. This led to the, Forest Conservation Act of 1980 and its amendment in 1988., India’s first Forest Policy was enunciated in 1952., Between 1952 and 1988, the extent of deforestation was so great that it became evident, that there was a need to formulate a new policy, on forests and their utilisation. Large tracts of, forestland had already been diverted to other, uses. The earlier forest policies had focused attention on revenue generation only. In the 1980s, , it became clear that forests must be protected, for their other functions such as maintenance, of soil and water regimes centered around ecological concerns. It also provided for the use of, goods and services of the forest for its local inhabitants., The new policy framework made conversion of, forests into other uses much less possible. Conservation of the forests as a natural heritage finds, a place in the new policy, which includes the, preservation of its biological diversity and genetic resources. It also values meeting the needs, of local people for food, fuelwood, fodder and, non-wood forest products that they subsist on., It gives priority to maintaining environmental, stability and ecological balance. It expressly, states that the network of Protected Areas, should be strengthened and extended., In 1992, the 73rd and 74th Amendments to the, Constitution furthered governance through, panchayats. It gives States the ability to provide, power to the local panchayats to manage local, forest resources., The Forest Conservation Act of 1980 was enacted to control deforestation. It ensured that, forestlands could not be de-reserved without, prior approval of the Central Government. This, was created as States had begun to de-reserve, the Reserved Forests for non-forest use. States, had regularized encroachments and resettled, ‘Project Affected People’ from development, projects such as dams in these de-reserved areas. The need for a new legislation became urgent. The Act made it possible to retain a greater, control over the frightening level of deforestation in the country and specified penalties for, offenders., Penalties for offences in Reserved Forests: No, person is allowed to make clearings or set fire, to a Reserved Forest. Cattle are not permitted, to trespass into the Reserved Forest. Felling,, collecting of timber, bark or leaves, quarries or, , Social Issues and The Environment, , Chapter6.p65, , 199, , 199, , 4/9/2004, 5:21 PM
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collecting any forest product is punishable with, imprisonment for a term of six months, or with, a fine which may extend to Rs.500, or both., , 3) Be in touch with concerned local NGOs and, associations. Organize one with other like, minded people if none exist in your area., , Penalties for offences in Protected Forests: A, person who commits any of the following offences like felling of trees, or strips off the bark, or leaves from any tree or sets fire to such forests, or kindles a fire without taking precautions, to prevent its spreading to any tree mentioned, in the Act, whether standing or felled, or fells, any tree, drags timber, or permits cattle to damage any tree, shall be punishable with imprisonment for a term which may extend to six month, or with a fine which may extend to Rs.500, or, both., , 4) Create awareness about the existence and, value of National Parks and Sanctuaries and, build up a public opinion against illegal activities in the forest or disturbance to wildlife., , When there is a reason to believe that a forest, offence has been committed pertaining to any, forest produce, the produce together with all, tools used in committing such offences may be, seized by any Forest Officer or Police Officer., Every officer seizing any property under this section shall put on the property a mark indicating, the seizure and report the seizure to the Magistrate who has the jurisdiction to try the offence., Any Forest Officer, even without an order from, the Magistrate or a warrant, can arrest any person against whom a reasonable suspicion exists., What can an individual do to support the Act?, 1) Be alert to destructive activities in your local green areas such as Reserved Forests and, Protected Forests, and in Protected Areas, (National Parks and Wildlife Sanctuaries)., Report any such act to the Forest Department as well as the Press. Report of violations can be made to the Conservator of, Forest, District Forest Officer, Range Forest, Officer, Forest Guard or the District Commissioner, or local civic body., , 5) Pressurize the authorities to implement the, forest and wildlife laws and rules to protect, green areas., 6) Take legal action if necessary and if possible through a Public Interest Litigation (PIL), against the offending party. Use the help, of NGOs who can undertake legal action., 7) Help to create public pressure to change, rules laws and procedures when necessary., 8) Use better, ecologically sensitive public, transport and bicycle tracks. Do not litter in, a forest area., 9) Participate in preservation of greenery, by, planting, watering and caring for plants., Whom should forest offences be reported to?, If you as a citizen come across anyone felling, trees, encroaching on forest land, dumping garbage, cutting green wood, lighting a fire, or creating a clearing in Reserved Forests, Protected, Forests, National Park, Sanctuary or other forest areas, you must report it to the forest / wildlife officers concerned. For urgent action one, can contact the police. In fact you should file an, FIR in any case because it serves as an important proof that you have made the report., , 2) Acquaint yourself with the laws, detailed, rules and orders issued by the Government., Environmental Studies for Undergraduate Courses, , 200, , Chapter6.p65, , 200, , 4/9/2004, 5:21 PM
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6.14 ISSUES INVOLVED IN ENFORCEMENT, OF ENVIRONMENTAL LEGISLATION, Environmental legislation is evolved to protect, our environment as a whole, our health, and, the earth’s resources. The presence of a legislation to protect air, water, soil, etc. does not necessarily mean that the problem is addressed., Once a legislation is made at the global, National or State level, it has to be implemented., For a successful environmental legislation to be, implemented, there has to be an effective, agency to collect relevant data, process it and, pass it on to a law enforcement agency. If the, law or rule is broken by an individual or institution, this has to be punished through the legal, process. Information to law enforcement officials must also come from concerned individuals. In most situations, if no cognizance is given,, the interested concerned individual must file a, Public Interest Litigation (PIL) for the protection, of the environment. There are several NGOs in, the country such as WWF-I, BEAG and the BNHS, which take these matters to court in the interest of conservation. Anyone can request them, to help in such matters. There are also legal experts such as MC Mehta who have successfully, fought cases in the courts to support environmental causes. A related issue is the fact that, there are several irregular practices for which a, bribe to an unscrupulous official is used to cover, up an offence. Thus the general public must act, as a watch dog not only to inform concerned, authorities, but also to see that actions are taken, against offenders., , 6.14.1 Environment Impact Assessment, (EIA):, For all development projects, whether Government or Private, the MoEF requires an impact, assessment done by a competent organisation., The EIA must look into physical, biological and, social parameters. EIAs are expected to indicate, what the likely impacts could be if the project is, , passed. The Ministry of Environment and Forests (MoEF) has identified a large number of, projects that need clearance on environmental, grounds. The EIA must define what impact it, would have on water, soil and air. It also requires that a list of flora and fauna identified, in the region is documented and to specify if, there are any endangered species whose habitat or life could be adversely affected. Most development projects such as industries, roads,, railways and dams may also affect the lives, of local people. This must be addressed in the, EIA. There are 30 different industries listed by, MoEF that require a clearance before they are, set up., Impacts created by each type of industry differs, and the proposed sites also vary in their sensitivity to impacts. Some areas are more fragile, than others. Some have unique ecosystems., Others are the habitats of wildlife and some may, be the home of endangered species of plants, or animals. All these aspects require evaluation, before a development project or an industry site, is cleared., New projects are called ‘green field projects’, where no development has been done. Projects, that already exist but require expansion must, also apply for clearance. These are called ‘brown, field projects’., After the Environmental Protection Act of 1986, was passed, an EIA to get an environmental, clearance for a project became mandatory., Project proponents are expected to select a competent agency to undertake an EIA. Projects can, be classified into those with a mild impact, a, moderate impact or a serious impact. Some may, have temporary major impacts, during the construction phase, which could later become less, damaging, or be mitigated by a variety of measures. In other situations the impact may continue and even increase, for example where toxic, solid waste will be constantly generated. Some, , Social Issues and The Environment, , Chapter6.p65, , 201, , 201, , 4/9/2004, 5:21 PM
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projects could thus cause temporary reversible, damage while others can have irreversible or, even permanent impacts., To get an environmental clearance the proposer, of the project is expected to apply to the State, Pollution Control Board. The PCB checks and, confirms that the EIA can be initiated. The, Agency that does the assessment submits a Report to the proposer. This may take several, months. A Report of the Environmental Statement is forwarded to the MoEF, which is the, impact assessment authority., After 1997, the MoEF has stipulated that a public, hearing should be done at the local level. The, Pollution Control Board puts an advertisement, about the hearing in the local vernacular press., An Environmental Impact Statement which is, an Executive Summary of the EIA is kept for the, public to read. The venue and time of the Public, Hearing is declared. Once the hearing is held, and opinions have been expressed, both for and, against the project, the minutes of the meeting, are sent to the MoEF. Though this is done, it is, evident that the voices of project affected people, are still not heard. In some cases NGOs have, taken up the cause of local people. Until educational levels and environmental awareness becomes a part of public thinking and is objectively, based on the facts of the case, these hearings, will remain an inadequate tool to control possible impacts of new development projects., Experience shows that a large number of EIAs, are inadequately researched and frequently biased as they are funded by the proposer of the, project. While most EIAs are adequate for studies on the possibilities of air, water and soil pollution, they generally deal inadequately with, issues such as preservation of biodiversity and, the social issues that may arise from future environmental impacts., Biodiversity concerns frequently are sketchily, considered and mostly consist of a listing of spe-, , Issues related to equity of resources that are inevitably altered by development related projects, are also not fully addressed. These cryptic concerns must be dealt with more seriously in environmental assessments and the public at large, should know and appreciate these inadequacies. It is not sufficient to say that an EIA has, been done. It is the quality and sincerity of the, EIA that is of importance., An EIA is not intended to stop all types of development. The siting of an industry can be selected carefully and if it is likely to damage a, fragile area an alternate less sensitive area must, be selected., In some cases it is essential to drop projects altogether if the anticipated impacts are likely to, be very severe. In other cases it is necessary for, the project to counter balance its effects by mitigating the ill effects on the environment. This, means compensating for the environmental, damage by afforestation or creating a Protected, Area in the neighbourhood at the cost of the, project. Rehabilitation and resettlement of, project affected people is a key concern which, should be given adequate funds and done after, a consent is clearly obtained from the people, living in the area. In most cases it is advisable to, avoid resettlement altogether. If an area’s vegetation is being affected project costs must include the cost of compensatory afforestation, and other protective measures., , 6.14.2 Citizens actions and action groups:, Citizens must learn to act as watch dogs to protect their own environment from the conseEnvironmental Studies for Undergraduate Courses, , 202, , Chapter6.p65, , cies without population assessments, or census, figures of wildlife, or a study of the effects on, the ecosystem as a whole. Changes in landuse, patterns effect whole communities of living organisms. This is rarely taken into account, as such, issues are difficult to assess in quantifiable terms., , 202, , 4/9/2004, 5:21 PM
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quences of unsustainable projects around them., Well informed citizens not only have rights but, also have a duty to perform in this regard. They, can join action groups to develop a lobby to, strengthen the environmental movements in the, country, their State, town or village., Individuals can take one or several possible actions when they observe offenders who for their, own self interest damage the environment for, others living in the area. An individual has the, right to bring an environmental offence or nuisance to the attention of concerned authorities., This ranges from Government line agencies such, as the Police, the Forest Department, the Collector or Commissioner of the area as the case, may be. At times the concerned officials may, not be able to easily appreciate complex environmental concerns and the individual may have, to learn how to communicate these issues in a, way in which it becomes essential for the concerned officer to act in a pro environmental fashion. If this does not work a citizen can seek legal, redressal under relevant statutes of law. The Environment Protection Act and the Wildlife Protection Act are the most frequently used legal, instrument for these purposes. It is possible to, move courts by a Public Interest Litigation, and, take this up to the Hon. Apex Court – the Supreme Court of India, which in the recent past, has given several highly enlightened pro-conservation judgements., Citizen groups can resort to alternate means of, pressure such as ‘rasta rokos’, ‘dharnas’, etc. to, draw attention to important environmental concerns. They can also elicit public support through, the press and electronic media., , CASE STUDY, The Narmada Issue, The controversy over the plan to build several dams on the Narmada River and its tributaries symbolizes the struggle for a just and, equitable society in India. The construction, of these dams displaces many poor and underprivileged communities, destroying their, relatively self-sufficient environmentally, sound economy and culture and reducing a, proud people to the status of refugees or, slum dwellers., The Narmada Bachao Andolan (Save the, Narmada Movement) is one of the most dynamic people’s movements fighting for the, rights of these underprivileged people who, are being robbed of their homes, livelihoods, and way of living in the name of ‘national, interest’., One such dam, the Sardar Sarovar Dam,, when completed will drown 37,000 hectares, of fertile land and displace 200,000 adivasis, and cause incomprehensible loss to the ecology., , CASE STUDY, Silent Valley, The proposed Hydel project at Silent valley,, a unique pocket of tropical biodiversity in, South India, in the 1970s was stopped and, the area declared a National Park in 1984., This was achieved by several dedicated individuals, groups and organisations lobbying, to save the area from being submerged and, protect its rich biodiversity., , Social Issues and The Environment, , Chapter6.p65, , 203, , 203, , 4/9/2004, 5:21 PM
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Among the many environmental battles that, have been fought in this country some have, been won while many others have been lost., These projects have led to serious environmental degradation in spite of the laws intended to, control such damage., , 6.15 PUBLIC AWARENESS, Environmental sensitivity in our country can only, grow through a major public awareness campaign. This has several tools. The electronic, media, the press, school and college education,, adult education, are all essentially complementary to each other. Green movements can grow, out of small local initiatives to become major, players in advocating environmental protection, to the Government. Policy makers will only work, towards environmental preservation if there is, a sufficiently large bank of voters that insist on, protecting the environment. Orienting the media to project pro environmental issues is an, important aspect. Several advertising campaigns, frequently have messages that are negative to, environmental preservation., , 6.15.1 Using an Environmental Calendar of, Activities:, There are several days of special environmental, significant which can be celebrated in the community and can be used for creating environmental awareness., February 2: World Wetland Day is celebrated, to create awareness about wetlands and their, value to mankind. On February 2nd 1971, the, Ramsar Convention on Wetlands of International, importance was signed at Ramsar in Iran. You, can initiate a campaign for proper use and maintenance of wetlands in the vicinity of the city or, village., , April 7: World Health Day – The World Health, Organisation (WHO) came into existence on this, day in 1948. A campaign for personal sanitation and hygiene to understanding issues of public health, occupational health, etc. can be, carried out. Topics that deal with environment, related diseases and their spread can be discussed and preventive measures suggested., April 18: World Heritage Day can be used to, arrange a visit to a local fort or museum. Environment also includes our cultural monuments., Students could use this opportunity to create, awareness among the local people about their, very valuable heritage sites., April 22: Earth Day was first celebrated in 1970, by a group of people in the USA to draw attention to increasing environmental problems, caused by humans on earth. This day is now, celebrated all over the world with rallies, festivals, clean-ups, special shows and lectures., June 5: World Environment Day marks the, anniversary of the Stockholm Conference on, Human Environment in Sweden in 1972, where, nations of the world gathered to share their, concern over human progress at the expense of, the environment. This day can be used to project, the various environmental activities that the, college has undertaken during the year. New, pledges must be made to strengthen an environmental movement at the college level., June 11: World Population Day is a day when, the vital link between population and environment could be discussed in seminars held at, college and other NGOs., Environmental Studies for Undergraduate Courses, , 204, , Chapter6.p65, , March 21: World Forestry Day can be used, to initiate a public awareness campaign about, the extremely rapid disappearance of our forests. The program must be action oriented and, become an ongoing process with activities such, as tree plantation., , 204, , 4/9/2004, 5:21 PM
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August 6: Hiroshima Day could be used to, discuss our own Bhopal Gas Tragedy and the, Chernobyl disaster., , globally and act locally’ to improve your own, environment. ‘You’ can make a difference to, our world., , September 16: World Ozone Day was proclaimed by the United Nations as the International Day for the preservation of the ozone, layer. This is a good occasion for students to, find out more about the threats to this layer, and initiate discussion on what they can do to, help mitigate this global threat. The day marks, the Montreal Protocol signed in 1987 to control, production and consumption of ozone depleting substances., , Biodiversity Conservation: A great proportion, of the residual wilderness of India is now under, great threat. Its unique landscapes are shrinking as the intensive forms of agriculture and industrial growth spreads through a process called, ‘development’. Modern science has serious, doubts about the possibility of the long-term, survival of the human race if man continues to, degrade natural habitats, extinguishes millions, of years of evolution through an extinction, spasm, and looks only at short-term gains. The, extinction of species cannot be reversed. Once, a species is lost, it is gone forever. Future generations will hold us responsible for this great, loss., , September 28: Green Consumer Day could, be used to create an awareness in consumers, about various products. Students could talk to, shopkeepers and consumers about excess packaging and a campaign to use articles which are, not heavily packaged could be carried out., October 1-7: Wildlife Week can consist of, seminars on conserving our species and threatened ecosystems. The State forest Departments, organize various activities in which every student should take part. A poster display, a street, play to highlight India’s rich biodiversity can be, planned. Wildlife does not only mean animals,, but includes plants as well., , We frequently forget that we are a part of a, great complex web of life and our existence, depends on the integrity of 1.8 million species, of plants and animals on earth that live in a large, number of ecosystems., The following are some of the things you can, do to contribute towards our ecological security and biodiversity conservation., , Dos:, 6.15.2 What can I do?, Most of us are always complaining about the, deteriorating environmental situation in our, country. We also blame the government for inaction. However how many of us actually do, anything about our own environment?, You can think about the things you can do that, support the environment in your daily life, in, your profession and in your community. You, can make others follow your environment, friendly actions. A famous dictum is to ‘think, , 1. Plant more trees of local or indigenous species around your home and your workplace., Encourage your friends to do so. Plants are, vital to our survival in many ways., 2. If your urban garden is too small for trees,, plant local shrubs and creepers instead., These support bird and insect life that form, a vital component of the food chains in, nature. Urban biodiversity conservation is, feasible and can support a limited but valuable diversity of life., , Social Issues and The Environment, , Chapter6.p65, , 205, , 205, , 4/9/2004, 5:21 PM
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3. If you live in an apartment, grow a terrace, or balcony garden using potted plants. Window boxes can be used to grow small flowering plants, which also add to the beauty, of your house., 4. Whenever and wherever possible prevent, trees from being cut, or if it is not possible, for you to prevent this, report it immediately to the concerned authorities. Old trees, are especially important., , 12. Support Project Tiger, Project Elephant, etc., and join NGOs that deal with environmental protection and nature conservation., 13. Involve yourself and friends in activities carried out during Wildlife Week and other, public functions such as tree plantation, drives and protests against destruction of, the environment., , Don’ts, 5. Insist on keeping our hills free of settlements, or similar encroachments. Degradation of, hill slopes leads to severe environmental, problems., 6. When shopping, choose products in limited, packaging. It will not only help cut down, on the amount of waste in landfills, but also, helps reduce our need to cut trees for paper and packaging., , 2. Do not collect unnecessary pamphlets and, leaflets just because they are free., , 7. Look for ways to reduce the use of paper., Use both sides of every sheet of paper. Send, your waste paper for recycling., , Habitat preservation: The rapid destruction of, forests, and the growth of human habitations, and activities have reduced the natural habitats, of animals and birds. Loss of habitat is one of, the major pressures on several species and has, led to the extinction of several rare and endemic, species. Many others are seriously threatened., We therefore have the responsibility to preserve, remaining habitats and their inhabitants., , 8. Buy recycled paper products for your home., For example sheets of paper, envelopes, etc., 9. Reuse cartons and gift-wrapping paper., Recycle newspaper and waste paper instead, of throwing it away as garbage., 10. Donate used books and magazines to, schools, hospitals, or libraries. The donations, will not only help these organizations, but, also will reduce the exploitation of natural, resources used to produce paper., 11. Participate in the events that highlight the, need for creating Sanctuaries and National, Parks, nature trails, open spaces, and saving forests., , 3. Do not use paper plates and tissues or paper decorations when you hold a party., , The following are some ‘dos and don’ts’ that, can help preserve threatened ecosystems., , Dos:, 1. Visit forests responsibly. Remember to bring, out everything you take in, and clean up, litter left by others. Stay on marked trails,, and respect the fact that wildlife need peace, and quiet. Study the ecosystem; it gives one, a greater sense of responsibility to conserve, it., Environmental Studies for Undergraduate Courses, , 206, , Chapter6.p65, , 1. Do not present flower bouquets instead give, a potted plant and encourage your friends, to do so., , 206, , 4/9/2004, 5:21 PM
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2. Be kind to animals. Stop friends from disturbing or being cruel to wild creatures such, as birds, frogs, snakes, lizards and insects., 3. Learn about birds. Identify birds that are, common in your area. Understand their, food requirements and feeding habits. Construct artificial nesting boxes for birds. This, will encourage birds to stay in your neighborhood, even if their nesting habitat is, scarce., , They have a right to a peaceful existence., The zoo is in any case not an ideal home for, them., , Don’ts, 1. Do not disturb, tease, hurt or throw stones, at animals in a Protected Area and stop others from doing so. If you see an injured animal contact the Forest Officials., , You can learn more about birds by making, a birdbath. Birds need water to drink and, to keep their feathers clean. You can make, a birdbath out of a big ceramic or plastic, saucer. Having birds around your home,, school or college can even help increase species diversity in the area., , 2. Do not disturb or destroy the natural habitats of birds or animals., , 4. Attract wildlife such as small mammals, such, as squirrels, to your garden by providing running or dripping water. Make a hole in the, bottom of a bucket and poke a string, through to serve as a wick. Hang a bucket, on a tree branch above your birdbath to, fill it gradually with water throughout the, day., , 4. Do not catch or kill butterflies or other insects. Butterflies, moths, bees, beetles and, ants are important pollinators., , 5. Protect wildlife, especially birds and insects, that are insectivorous and live in your neighborhood by eliminating the use of chemicals in your garden. Instead, use organic, measures from vermicomposting and by, introducing natural pest predators. Do your, gardening and landscaping using local, plants, to control pests in your garden., 6. If you have pets, feed them well and give, them a proper home and in an emergency, proper medical care., 7. When you visit a zoo learn about the animals that are found there but do not tease, or hurt them through the bars of their cage., , 3. Do not use articles like leather handbags, and lipsticks, which are made from animal, products. No wildlife products should be, used., , 5. Do not kill small animals and insects like, dragonflies and spiders as they act as biological pest control mechanisms., 6. Do not bring home animals or plants collected in the wild. You could be seriously, harming wild populations and natural ecosystems where they were collected., 7. Do not buy products like purses, wallets,, boots and that are made from reptile skins., If you are not certain that a product is made, from a wild species, its better to avoid using it., 8. Do not buy products made from ivory. Elephants are killed for their tusks, which are, used to make a variety of ivory products., 9. Do not use any wild animal or plant products that are collected from the wild and, , Social Issues and The Environment, , Chapter6.p65, , 207, , 207, , 4/9/2004, 5:21 PM
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have dubious medicinal properties. You may, be endangering a species and even your, own health., Soil conservation: Soil degradation affects us, all in some way, either directly or indirectly. There, are many ways that each of us can help in solving environmental problems due to loss of soil., Following are some of the dos and don’ts for, conserving soil., , 5. Add organic matter to enrich your garden, soil. For example compost from kitchen, scraps and manure from poultry, cows are, good sources of nutrients. Make sure manure is not too fresh and that you do not, use too much. Healthy soil grows healthy, plants, and it lessens the need for insecticides and herbicides., 6. In your vegetable garden, rotate crops to, prevent the depletion of nutrients. Legumes, such as peas and beans put nitrogen back, into the soil., , Dos:, 1. Cover the soil in your farm or garden with, a layer of mulch to prevent soil erosion in, the rains and to conserve soil moisture., Mulch can be made from grass clippings or, leaf litter., 2. If you plan to plant on a steep slope in your, farm or garden, prevent soil erosion by first, terracing the area. Terraces help in slowing, the rain water running downhill so it can, soak into the soil rather than carry the soil, away., 3. Help prevent soil erosion in your community by planting trees and ground-covering, plants that help hold the soil in place. You, might organize a group of citizens to identify places that need planting, raise funds,, work with the local government to plant, trees, shrubs and grasses, and maintain, them over the long term., 4. If your college is surrounded by open space,, evaluate how well the soil is being conserved. Look for places where soil can run, off, like on an unplanted steep slope or, stream bank, or where soil is exposed rather, than covered with mulch. These areas need, special care and must be carefully replanted., , 8. Encourage your local zoo, farms, and other, organizations or people that house a large, number of animals to provide your community with bioferilizer made from animal, manure. This can be composted to make a, rich fertilizer, and it forms an additional, source of income for the animal owners., 9. Buy organically grown produce to help reduce the amount of toxic pesticides used in, farms that harm soil organisms. Look for, organically grown produce in your grocery, shop, or try growing some yourself if you, have the space., 10. Support environmental campaigns in your, State and community. Cutting down on irresponsible development can protect soil,, biodiversity, and enhance our quality of life., Environmental Studies for Undergraduate Courses, , 208, , Chapter6.p65, , 7. Set up a compost pit in your college or garden, so that you can enrich your soil with, the organic waste from the kitchen and cut, down on the amount of waste it sends to a, landfill. Set up buckets in your college or, lunchroom where fruit and left-over food, can be put. Empty the buckets daily into a, compost pit, and use the rich compost, formed in a few weeks to enrich the soil, around the college. Kitchen scraps, leaves, and grass clippings are excellent compost., , 208, , 4/9/2004, 5:21 PM
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7. Use a drip irrigation system to water more, efficiently., , Don’ts:, 1. Do not remove grass, leave it on the lawn., Cuttings serve as moisture-retention mulch, and a natural fertilizer., 2. Do not use toxic pesticides in your garden—, they often kill the beneficial organisms, your, soil needs to stay healthy., Conserving water: Most of India has good average annual rainfall, however we still face a, water shortage nearly everywhere. This is one, of the major environmental problems in our, country. Conservation of this very precious natural resource is very important and it is the need, of the hour. It should start with every individual., It must start with you! Following are some of, the things you can do to conserve this precious, natural resource., , Dos:, 1. Reduce the amount of water used for daily, activities. For example - turn off the tap, while brushing your teeth to save water., 2. Reuse the rinsing water for house-plants., Reuse the water that vegetables are washed, in to water the plants in your garden or your, potted plants., 3. Always water the plants early in the morning to minimize evaporation., 4. Soak the dishes before washing them to, reduce water and detergent usage., 5., , Look for leaks in the toilet and bathroom, to save several litres of water a day., , 6. While watering plants, water only as rapidly as the soil can absorb the water., , 8. When you need to drink water, take only, as much as you need to avoid wastage. So, many people in our country don’t even have, access to clean drinking water!, 9. Saving precious rainwater is very important., Harvest rainwater from rooftops and use it, sustainably to recharge wells to reduce the, burden on rivers and lakes., 10. Monitor and control wastes going into, drains for preventing water pollution., 11. Replace chemicals like phenyl, strong detergents, shampoo, chemical pesticides and, fertilizers used in your home, with environment friendly alternatives, such as neem and, biofertilisers. Groundwater contamination, by household chemicals is a growing concern., 12. For Ganesh Chaturthi, bring home a, ‘Shadu’ idol instead of a Plaster of Paris idol, and donate it instead of immersing it in the, river to reduce river pollution., , Don’ts:, 1. Do not turn your tap on full force, instead, maintain a slow flow., 2. Do not use a shower, instead use a bucket, of water for bathing. A 10 minute shower, wastes many liters of water as compared, to using water from a bucket., 3. Do not over water garden plants, water, them only when necessary., 4. Do not pollute sources of water or water, bodies by throwing waste into them. This is, the water you or someone else has to drink!, , Social Issues and The Environment, , Chapter6.p65, , 209, , 209, , 4/9/2004, 5:21 PM
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5. Do not throw waste into toilets because finally it goes into water bodies., Conserving energy: Coal, petroleum and oil, are mineral resources and are non-renewable, sources of energy. At the current rate of fossil, fuel consumption, the present oil reserves on, the earth will last only for the next 30 to 50, years. Crores of rupees are being spent to extract, process and distribute coal, petroleum and, electricity. Experiments are being carried out to, generate energy from wind, and photovoltaic, cells. They are highly successful. At an individual, level, every one of us should try to conserve energy. Following are some of the things you can, do to conserve energy., , 9. Turn off the stove immediately after use., 10. Plan and keep things ready before you start, cooking., 11. Keep vessels closed while cooking and always use small, narrow mouthed vessels to, conserve energy., 12. When the food is almost cooked, switch, off the gas stove and keep the vessel closed., It will get completely cooked with the steam, already present inside., 13. Soak rice, pulses etc., before cooking to, reduce cooking time and save fuel., 14. Get your family to eat together, it will save, re-heating fuel., , Dos:, 1. Turn off the lights fans and air conditioning, when not necessary., , 15. Select a light shade of paint for walls and, ceilings, as it will reflect more light and reduce electrical consumption., , 2. Use low voltage lights., 3. Use tube lights and energy saver bulbs as, they consume less electricity., 4. Switch off the radio and television when not, required., 5. Use alternative sources of energy like solar, power for heating water and by cooking, food in a solar cooker., 6. Cut down on the use of electrical appliances., 7. In summer, shut windows, curtains and, doors early in the morning to keep the, house cool., 8. Use a pressure cooker as much as possible, to save energy., , 17. Use a bicycle—it occupies less space, releases no pollutant and provides healthy, exercise., 18. Try using public transport systems like trains, and buses as far as possible., 19. Plan your trips and routes before setting out., 20. Walk rather than drive wherever possible., Walking is one of the best exercises for your, health., 21. Get vehicles serviced regularly to reduce fuel, consumption and reduce pollution levels., , Environmental Studies for Undergraduate Courses, , 210, , Chapter6.p65, , 16. Position your reading tables near the window and cut down on your electricity bill, by reading in natural light., , 210, , 4/9/2004, 5:21 PM
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Don’ts:, 1. Do not use unnecessary outdoor decorative, lights., 2. Do not use a geyser during summer. Instead,, heat water naturally with the help of sunlight., 3. Do not use halogen lamps as they consume, a lot of electricity., 4. Do not put food in the refrigerator when, they are still hot., , Social Issues and The Environment, , Chapter6.p65, , 211, , 211, , 4/9/2004, 5:21 PM
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UNIT 7:, , Human Population and the Environment, 7.1 POPULATION GROWTH, VARIATION AMONG NATIONS, 7.1.1 Global population growth, , 214, 214, , 7.2 POPULATION EXPLOSION – FAMILY WELFARE PROGRAM, 7.2.1 Methods of sterilization, 7.1.2 Urbanization, , 215, 217, 217, , 7.3 ENVIRONMENTAL AND HUMAN HEALTH, 7.3.1 Environmental health, 7.3.2 Climate and health, 7.3.3 Infectious diseases, 7.3.4 Water-related diseases, 7.3.5 Risks due to chemicals in food, 7.3.6 Cancer and environment, , 220, 221, 223, 224, 227, 231, 232, , 7.4 HUMAN RIGHTS, 7.4.1 Equity, 7.4.2 Nutrition, health and human rights, 7.4.3 Intellectual Property Rights and Community Biodiversity Registers, , 233, 233, 234, 235, , 7.5 VALUE EDUCATION, 7.5.1 Environmental Values, 7.5.2 Valuing Nature, 7.5.3 Valuing cultures, 7.5.4 Social justice, 7.5.5 Human heritage, 7.5.6 Equitable use of Resources, 7.5.7 Common Property Resources, 7.5.8 Ecological degradation, , 236, 237, 240, 241, 241, 242, 242, 242, 242, , 7.6 HIV/AIDS, , 243, , 7.7 WOMEN AND CHILD WELFARE, , 244, , 7.8 ROLE OF INFORMATION TECHNOLOGY IN ENVIRONMENT AND HUMAN HEALTH 247, Human Population and the Environment, , Chapter7.p65, , 213, , 213, , 4/9/2004, 5:09 PM
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7.1 POPULATION GROWTH, VARIATION, AMONG NATIONS, Our global human population, 6 billion at, present, will cross the 7 billion mark by 2015., The needs of this huge number of human beings cannot be supported by the Earth’s natural, resources, without degrading the quality of human life., In the near future, fossil fuel from oil fields will, run dry. It will be impossible to meet the demands for food from existing agro systems. Pastures will be overgrazed by domestic animals, and industrial growth will create ever-greater, problems due to pollution of soil, water and air., Seas will not have enough fish. Larger ozone, holes will develop due to the discharge of industrial chemicals into the atmosphere, which, will affect human health. Global warming due, to industrial gases will lead to a rise in sea levels, and flood all low-lying areas, submerging coastal, agriculture as well as towns and cities. Water, ‘famines’ due to the depletion of fresh water,, will create unrest and eventually make countries go to war. The control over regional biological diversity, which is vital for producing new, medicinal and industrial products, will lead to, grave economic conflicts between, biotechnologically advanced nations and the biorich countries. Degradation of ecosystems will, lead to extinction of thousands of species, destabilizing natural ecosystems of great value., These are only some of the environmental problems related to an increasing human population and more intensive use of resources that, we are likely to face in future. These effects can, be averted by creating a mass environmental, awareness movement that will bring about a, change in people’s way of life., Increase in production per capita of agricultural, produce at a global level ceased during the, 1980’s. In some countries, food shortage has, become a permanent feature. Two of every, three children in South Africa are underweight., , The increasing pressures on resources place, great demands on the in-built buffering action, of nature that has a certain ability to maintain a, balance in our environment. However, current, development strategies that essentially lead to, short-term gains have led to a breakdown of, our Earth’s ability to replenish the resources on, which we depend., , 7.1.1 Global population growth, The world population is growing by more than, 90 million per year, of which 93% is in developing countries. This will essentially prevent their, further economic ‘development’. In the past,, population growth was a gradual phenomenon, and the Earth’s ability to replenish resources was, capable of adjusting to this increase. In the recent past, the escalation in growth of human, numbers has become a major cause of our environmental problems., Present projections show that if our population, growth is controlled, it will still grow to 7.27, billion by 2015. However, if no action is taken it, will become a staggering 7.92 billion., Human population growth increased from:, 1 to 2 billion, in 123 years., 2 to 3 billion, in 33 years., Environmental Studies for Undergraduate Courses, , 214, , Chapter7.p65, , In other regions famines due to drought have, become more frequent. Present development, strategies have not been able to successfully, address these problems related to hunger and, malnutrition. On the other hand, only 15% of, the world’s population in the developed world, is earning 79% of income! Thus the disparity in, the extent of per capita resources that are used, by people who live in a ‘developed’ country as, against those who live in a ‘developing’ country is extremely large. Similarly, the disparity, between the rich and the poor in India is also, growing., , 214, , 4/9/2004, 5:09 PM
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3 to 4 billion, in 14 years., 4 to 5 billion, in 13 years., 5 to 6 billion, in 11 years., It is not the census figures alone that need to, be stressed, but an appreciation of the impact, on natural resources of the rapid escalation in, the rate of increase of human population in the, recent past. The extent of this depletion is further increased by affluent societies that consume, per capita more energy and resources, that less, fortunate people. This is of great relevance for, developing a new ethic for a more equitable, distribution of resources., In the first half of the 1900s human numbers, were growing rapidly in most developing countries such as India and China. In some African, countries the growth was also significant. In contrast, in the developed world population growth, had slowed down. It was appreciated that the, global growth rate was depleting the Earth’s, resources and was a direct impediment to human development. Several environmental ill-effects were linked with the increasing population, of the developing world. Poverty alleviation programs failed, as whatever was done was never, enough as more and more people had to be, supported on Earth’s limited resources. In rural, areas population growth led to increased, fragmentation of farm land and unemployment., In the urban sector it led to inadequate housing, and an increasing level of air pollution from, traffic, water pollution from sewage, and an, inability to handle solid waste. By the 1970s, most countries in the developing world had, realized that if they had to develop their, economics and improve the lives of their citizens they would have to curtail population, growth., Though population growth shows a general global decline, there are variations in the rate of, decline in different countries. By the 1990s the, growth rate was decreasing in most countries, , such as China and India. The decline in the 90s, was greatest in India. However, fertility continues to remain high in sub Saharan African countries., There are cultural, economic, political and demographic reasons that explain the differences, in the rate of population control in different, countries. It also varies in different parts of certain countries and is linked with community and/, or religious thinking. Lack of Government initiatives for Family Welfare Program and a limited access to a full range of contraceptive, measures are serious impediments to limiting, population growth in several countries., , 7.2 POPULATION EXPLOSION – FAMILY, WELFARE PROGRAM, In response to our phenomenal population, growth, India seriously took up an effective Family Planning Program which was renamed the, Family Welfare Program. Slogans such as, ‘Hum do hamare do’ indicated that each family, should not have more than two children. It however has taken several decades to become effective., At the global level by the year 2000, 600 million, or 57% of women in the reproductive age, group, were using some method of contraception. However the use of contraceptive measures is higher in developed countries – 68%,, and lower in developing countries - 55%. Female sterilization is the most popular method, of contraception used in developing countries, at present. This is followed by the use of oral, contraceptive pills and, intrauterine devices for, women, and the use of condoms for men. India, and China have been using permanent sterilization more effectively than many other countries in the developing world., , Human Population and the Environment, , Chapter7.p65, , 215, , 215, , 4/9/2004, 5:09 PM
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The best decision for the method used by a, couple depends on a choice that they make for, themselves. This must be based on good advice, from doctors or trained social workers who can, suggest the full range of methods available for, them to choose from., Informing the public about the various contraceptive measures that are available is of primary, importance. This must be done actively by, Government Agencies such as Health and, Family Welfare, as well as Education and Extension workers. It is of great importance for policy, makers and elected representatives of the, people – Ministers, MPs, MLAs at Central, and State levels – to understand the great, and urgent need to support Family Welfare., The media must keep people informed, about the need to limit family size and the ill, effects of a growing population on the worlds, resources., The decision to limit family size depends on a, couple’s background and education. This is related to Government Policy, the effectiveness, of Family Welfare Programs, the educational, level, and information levels in mass communication. Free access to Family Welfare information provided through the Health Care System,, is in some cases unfortunately counteracted by, cultural attitudes. Frequently misinformation and, inadequate information are reasons why a family, does not go in for limiting its size., The greatest challenge the world now faces is, how to supply its exploding human population, with the resources it needs. It is evident that, without controlling human numbers, the Earth’s, resources will be rapidly exhausted. In addition, economically advanced countries and rich, people in poorer countries use up more resources than they need., As population expands further, water shortages, will become acute. Soil will become unproduc-, , The first ‘green revolution’ in the ‘60s produced, a large amount of food but has led to several, environmental problems. Now, a new green, revolution is needed, to provide enough food, for our growing population, that will not damage land, kill rivers by building large dams, or, spread at the cost of critically important forests,, grasslands and wetlands., The world’s most populous regions are in coastal, areas. These are critical ecosystems and are being rapidly destroyed. Global climate change is, now a threat that can affect the very survival of, high population density coastal communities. In, the sea, fish populations are suffering from excessive fishing. Once considered an inexhaustible resource, over fishing has depleted stocks, extremely rapidly. It will be impossible to support further growth in coastal populations on, existing fish reserves., Human populations will inevitably expand from, farm lands into the remaining adjacent forests., Many such encroachments in India have been, regularised over the last few decades. But forest loss has long-term negative effects on water and air quality and the loss of biodiversity is, still not generally seen as a major deterrent to, human well-being. The extinction of plant and, animal species resulting from shrinking habitats, threatens to destroy the Earth’s living web of, life., Energy use is growing, both due to an increasing population, and a more energy hungry, lifestyle that increasingly uses consumer goods, that require large amounts of energy for their, Environmental Studies for Undergraduate Courses, , 216, , Chapter7.p65, , tive. Rivers, lakes and coastal waters will be increasingly polluted. Water related diseases already kill 12 million people every year in the, developing world. By 2025, there will be 48, countries that are starved for water. Air will, become increasingly polluted. Air pollution already kills 3 million people every year., , 216, , 4/9/2004, 5:09 PM
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production, packaging, and transport. Our, growing population also adds to the enormous, amount of waste., With all these linkages between population, growth and the environment, Family Welfare, Programs have become critical to human existence., , Planning for the future, How Governments and people from every, community meet challenges such as limiting, population size, protecting the natural environment, change their consumer oriented, attitudes, reduce habits that create excessive waste, elevates poverty and creates an, effective balance between conservation and, development will determine the worlds future., , The Urban Challenge, Population increases will continue in urban, centers in the near future. The UN has shown, that by 2025 there will be 21 "megacities", most of which will be situated in developing, countries. Urban centers are already unable, to provide adequate housing, services such, as water and drainage systems, growing energy needs, or better opportunities for income generation., , The most effective measure is the one most, suited to the couple once they have been offered all the various options that are available., The Family Welfare Program advocates a variety of measures to control population. Permanent methods or sterilisation are done by a minor, surgery. Tubectomy in females is done by tying, the tubes that carry the ovum to the uterus., Male sterilization or vasectomy, is done by tying the tubes that carry the sperm. Both are very, simple procedures, done under local anesthesia, are painless and patients have no post operative problems. Vasectomy does not cause any, loss in the male’s sexual ability but only arrests, the discharge of sperm., There are several methods of temporary birth, control. Condoms are used by males to prevent, sperms from fertilizing the ovum during intercourse. Intrauterine devices (Copper Ts) are small, objects which can be placed by a doctor in the, uterus so that the ovum cannot be implanted,, even if fertilized. They do not disturb any functions in the woman’s life or work. Oral contraceptive tablets (pills) and injectable drugs are, available that prevent sperms from fertilizing the, ovum., There are also traditional but less reliable methods of contraception such as abstinence of the, sexual act during the fertile period of the, women’s cycle and withdrawal during the sexual, act., , 7.2.2 Urbanization:, , 7.2.1 Methods of sterilization, India’s Family Welfare Program has been fairly, successful but much still needs to be achieved, to stabilize our population., , In 1975 only 27% of the people in the developing world lived in urban areas. By 2000 this had, grown to 40% and by 2030 well informed estimates state that this will grow to 56%. The developed world is already highly urbanized with, 75% of its population living in the urban sector., , Human Population and the Environment, , Chapter7.p65, , 217, , 217, , 4/9/2004, 5:09 PM
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CASE STUDY, Urban Environments, Nearly half the world's population now lives, in urban areas. The high population density, in these areas leads to serious environmental issues., Today, more than 290 million people live in, towns and cities in India. There were 23, metros in India in 1991, which grew to 40, by 2001., , Urban population growth is both due to migration of people to towns and cities from the rural sector in search of better job options as well, as population growth within the city., As a town grows into a city it not only spreads, outwards into the surrounding agricultural land, or natural areas such as forests, grasslands and, wetlands but also grows skywards with high rise, buildings. The town also loses its open spaces, and green cover unless these are consciously, preserved. This destroys the quality of life in the, urban area., Good urban planning is essential for rational, landuse planning, for upgrading slum areas,, improving water supply and drainage systems,, providing adequate sanitation, developing effective waste water treatment plants and an, efficient public transport system., , Unplanned and haphazard growth of urban, complexes has serious environmental impacts. Increasing solid waste, improper garbage disposal and air and water pollution, are frequent side effects of urban expansions., , Apart from undertaking actions that support the, environment every urban individual has the ability to influence a city’s management. He or she, must see that the city’s natural green spaces,, parks and gardens are maintained, river and, water fronts are managed appropriately, roadside tree cover is maintained, hill slopes are afforested and used as open spaces and, architectural and heritage sites are protected., Failure to do this leads to increasing urban problems which eventually destroys a city’s ability to, maintain a healthy and happy lifestyle for its, dwellers. All these aspects are closely linked to, the population growth in the urban sector. In, many cities growth outstrips the planner’s ability to respond to this in time for a variety of, reasons., Mega cities, in India, , Population, (in millions), in 2001, , Projection, (in millions), for 2015, , Mumbai, , 16.5, , 22.6, , Kolkata, , 13.3, , 16.7, , Delhi, , 13.0, , 20.9, , Small urban centers too will grow rapidly during the next decades and several rural areas will, require reclassification as urban centers. India’s, urban areas will grow by a projected 297 million residents. In India people move to cities from, rural areas in the hope of getting a better income. This is the ‘Pull’ factor. Poor opportunities in the rural sector thus stimulates migration, to cities. Loss of agricultural land to urbanisation, and industry, the inability of governments to, sustainably develop the rural sector, and a lack, Environmental Studies for Undergraduate Courses, , 218, , Chapter7.p65, , While all these issues appear to be under the, preview of local Municipal Corporations, better, living conditions can only become a reality if, every citizen plays an active role in managing, the environment. This includes a variety of “Dos, and Don’ts” that should become an integral part, of our personal lives., , 218, , 4/9/2004, 5:09 PM
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Megacities – Over 10 million inhabitants., 1950 – there was only 1 – New York., 1975 – there were 5., 2001 – there were 15 (with Mumbai,, Kolkata, and Delhi, being added to the list, from India)., 2015 – there will be 21 megacities., Cities over 1 million in size:, In 2000 there were 388 cities with more than, 1 million inhabitants., By 2015 these will increase to 554, of which, 75% are in developing countries., of supporting infrastructure in rural areas, all, push people from the agricultural and natural, wilderness ecosystems into the urban sector., As our development strategies have focused, attention mostly on rapid industrial development, and relatively few development options are offered for the agricultural rural sector, a shift of, population is inevitable., , As population in urban centers grows, they, draw on resources from more and more distant areas. The "Ecological footprint" corresponds to the land area necessary to supply, natural resources and disposal of waste of a, community. At present the average ecological footprint of an individual at the global, level is said to be 2.3 hectares of land per, capita. But it is estimated that the world has, only 1.7 hectares of land per individual to, manage these needs sustainably. This is thus, an unsustainable use of land., , The pull factor of the urban centers is not only, due to better job opportunities, but also better, education, health care and relatively higher living standards. During the last few decades in, India, improvements in the supply of clean wa-, , ter, sanitation, waste management, education, and health care has all been urban centric, even, though the stated policy has been to support, rural development. Thus in reality, development, has lagged behind in the rural sector that is rapidly expanding in numbers,. For people living in, wilderness areas in our forests and mountain, regions, development has been most neglected., It is not appropriate to use the development, methods used for other rural communities for, tribal people who are dependent on collecting, natural resources from the forests. A different, pattern of development that is based on the, sustainable extraction of resources from their, own surroundings would satisfy their development aspirations. In general the growing human population in the rural sector will only opt, to live where they are if they are given an equally, satisfying lifestyle., , The wilderness – rural-urban linkage, The environmental stresses caused by urban, individuals covers an 'ecological footprint', that goes far beyond what one expects. The, urban sector affects the land at the fringes, of the urban area and the areas from which, the urban center pulls in agricultural and, natural resources., Urban centers occupy 2% of the worlds' land, but use 75% of the industrial wood. About, 60% of the world's water is used by urban, areas of which half irrigates food crops for, urban dwellers, and one third goes to industry and the rest is used for household use, and drinking water., The impact that urban dwellers have on the, environment is not obvious to them as it happens at distant places which supports the, urban ecosystem with resources from agricultural and even more remote wilderness, ecosystems., , Human Population and the Environment, , Chapter7.p65, , 219, , 219, , 4/9/2004, 5:09 PM
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Urban poverty and the Environment, The number of poor people living in urban areas is rapidly increasing. A third of the poor, people in the world live in urban centers. These, people live in hutments in urban slums and suffer from water shortages and unsanitary conditions. In most cases while a slum invariably has, unhygenic surroundings, the dwellings themselves are kept relatively clean. It is the ‘common’ areas used by the community that lacks, the infrastructure to maintain a hygienic environment., During the 1990s countries that have experienced an economic crisis have found that poor, urban dwellers have lost their jobs due to decreasing demands for goods, while food prices, have risen. Well paid and consistent jobs are not, as easily available in the urban centers at present, as in the past few decades., , air pollution due to high levels of particulate, matter and sulphur dioxide from industrial and, vehicle emissions lead to high death rates from, respiratory diseases. Most efforts are targeted, at outdoor air pollution. Indoor air pollution due, to the use of fuel wood, waste material, coal,, etc. in ‘chulas’ is a major health issue. This can, be reduced by using better designed ‘smokeless’ chulas, hoods and chimneys to remove indoor smoke., With the growing urban population, a new crisis of unimaginable proportions will develop in, the next few years. Crime rates, terrorism, unemployment, and serious environmental health, related issues can be expected to escalate. This, can only be altered by stabilizing population, growth on a war footing., , 7.3 ENVIRONMENT AND HUMAN HEALTH, One billion urban people in the world live in inadequate housing, mostly in slum areas, the, majority of which are temporary structures., However, low income groups that live in high, rise buildings can also have high densities and, live in poor unhygienic conditions in certain areas of cities. Illegal slums often develop on, Government land, along railway tracks, on hill, slopes, riverbanks, marshes, etc. that are unsuitable for formal urban development. On the, riverbanks floods can render these poor people, homeless. Adequate legal housing for the urban poor remains a serious environmental concern., Urban poverty is even more serious than rural, poverty, as unlike the rural sector, the urban, poor have no direct access to natural resources, such as relatively clean river water, fuelwood, and non wood forest products. The urban poor, can only depend on cash to buy the goods they, need, while in the rural sector they can grow a, substantial part of their own food. Living conditions for the urban poor are frequently worse, than for rural poor. Both outdoor and indoor, , Environmental Studies for Undergraduate Courses, , 220, , Chapter7.p65, , Environment related issues that affect our health, have been one of the most important triggers, that have led to creating an increasing awareness of the need for better environmental management. Changes in our environment induced, by human activities in nearly every sphere of life, have had an influence on the pattern of our, health. The assumption that human progress is, through economic growth is not necessarily true., We expect urbanization and industrialization to, bring in prosperity, but on the down side, it leads, to diseases related to overcrowding and an inadequate quality of drinking water, resulting in, an increase in waterborne diseases such as infective diarrhoea and air borne bacterial diseases, such as tuberculosis. High-density city traffic, leads to an increase in respiratory diseases like, asthma. Agricultural pesticides that enhanced, food supplies during the green revolution have, affected both the farm worker and all of us who, consume the produce. Modern medicine promised to solve many health problems, especially, associated with infectious diseases through antibiotics, but bacteria found ways to develop, , 220, , 4/9/2004, 5:09 PM
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resistant strains, frequently even changing their, behaviour in the process, making it necessary, to keep on creating newer antibiotics. Many, drugs have been found to have serious side effects. At times the cure is as damaging as the, disease process itself., , wide. The El Niño event of 1997/98 had serious, impacts on health and well-being of millions of, people in many countries. It created serious, drought, floods, and triggered epidemics. New, strategies must be evolved to reduce vulnerability to climate variability and changes., , Thus development has created several long-term, health problems. While better health care has, led to longer life spans, coupled with a lowered, infant mortality, it has also led to an unprecedented growth in our population which has, negative implications on environmental quality., A better health status of society will bring about, a better way of life only if it is coupled with, stabilising population., , Economic inequality and environmental changes, are closely connected to each other. Poor countries are unable to meet required emission standards to slow down climate change. The, depletion of ozone in the stratosphere (middle, atmosphere) also has an important impact on, global climate and in turn human health, increasing the amount of harmful ultraviolet radiation, that reaches the Earth’s surface. This results in, diseases such as skin cancer., , 7.3.1 Environmental health, as defined by, WHO, comprises those aspects of human, health, including quality of life, that are determined by physical, chemical, biological, social,, and psychosocial factors in the environment., It also refers to the theory and practice of assessing, correcting, controlling, and preventing, those factors in the environment that adversely, affect the health of present and future generations., Our environment affects health in a variety of, ways. Climate and weather affect human health., Public health depends on sufficient amounts of, good quality food, safe drinking water, and adequate shelter. Natural disasters such as storms,, hurricanes, and floods still kill many people every year. Unprecedented rainfall trigger epidemics of malaria and water borne diseases., Global climate change has serious health implications. Many countries will have to adapt to, uncertain climatic conditions due to global, warming. As our climate is changing, we may, no longer know what to expect. There are increasing storms in some countries, drought in, others, and a temperature rise throughout the, world. The El Niño winds affect weather world-, , CASE STUDY, Bhopal Gas Tragedy, The siting of industry and relatively poor, regulatory controls leads to ill health in the, urban centers. Accidents such as the Bhopal, gas tragedy in 1984 where Union Carbide's, plant accidentally released 30 tones of methyl isocyanate, used in the manufacture of, pesticides, led to 3,330 deaths and 1.5 lakh, injuries to people living in the area., , Development strategies that do not incorporate, ecological safeguards often lead to ill health., Industrial development without pollution control and traffic congestion affect the level of air, pollution in many cities. On the other hand, development strategies that can promote health, invariably also protect the environment. Thus, environmental health and human health are, SUSTAINABLE DEVELOPMENT, , HEALTHY ENVIRONMENT, , Human Population and the Environment, , Chapter7.p65, , 221, , HEALTHY PEOPLE, , 221, , 4/9/2004, 5:09 PM
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•, , Hundreds of millions of people suffer serious respiratory diseases, including lung cancer and tuberculosis, from crowded homes, and public places. Motor vehicle exhaust, fumes, industrial fumes, tobacco smoke and, cooking food on improper ‘chulas’, contribute to respiratory diseases., , Millions of children die every year due to, diarrhoea from contaminated water or, food. An estimated 2000 million people are, affected by these diseases and more than 3, million children die each year from waterborne diseases across the world. In India, it, is estimated that every fifth child under the, age of 5 dies due to diarrhoea. This is a result of inadequate environmental management and is mainly due to inadequate, purification of drinking water. Wastewater, and/or sewage entering water sources without being treated leads to continuous gastrointestinal diseases in the community and, even sporadic large epidemics. Large numbers of people in tropical countries die of, malaria every year and millions are infected., An inadequate environmental management, of stagnant water, which forms breeding, sites of Anopheles mosquitoes is the most, important factor in the spread of malaria., The resurgence of malaria in India is leading to cerebral malaria that affects the brain, and has a high mortality., , •, , Millions of people are exposed to hazardous chemicals in their workplace or homes, that lead to ill health due to industrial products where controls are not adhered to., , •, , Tens of thousands of people in the world, die due to traffic accidents due to inadequate management of traffic conditions., Poor management at the accident site, and, inability to reach a hospital within an hour, causes a large number of deaths, especially, from head injuries., , •, , Basic environmental needs such as clean, water, clean air and adequate nutrition, which are all related to environmental goods, and services do not reach over 1000 million, people living in abject poverty., , •, , Several million people live in inadequate, shelters or have no roof over their heads, especially in urban settings. This is related, to high inequalities in the distribution of, wealth and living space., , Millions of people, mainly children, have, poor health due to parasitic infections, such, as amoebiasis and worms. This occurs from, eating infected food, or using poor quality, water for cooking food. It is estimated that, 36% of children in low-income countries, and 12% in middle income countries are, malnourished. In India, about half the children under the age of four are malnourished and 30% of newborns are significantly, underweight., , •, , Population growth and the way resources, are being exploited and wasted, threatens, environmental integrity and directly affects, health of nearly every individual., , •, , Health is an outcome of the interactions, between people and their environment., Better health can only come from a more, sustainable management of the environment., , closely interlinked. An improvement in health is, central to sound environmental management., However this is rarely given sufficient importance, in planning development strategies., , Examples of the linkages:, •, , •, , Environmental Studies for Undergraduate Courses, , 222, , Chapter7.p65, , 222, , 4/9/2004, 5:09 PM
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Important strategic concerns, •, , The world must address people’s health care, needs and sustainable use of natural resources, which are closely linked to each, other., , •, , Strategies to provide clean pottable, water and nutrition to all people is an, important part of a healthy living environment., , •, , Providing clean energy sources that do not, affect health is a key to reducing respiratory diseases., , •, , Reducing environmental consequences of, industrial and other pollutants such as transport emissions can improve the status of, health., , •, , Changing patterns of agriculture away from, harmful pesticides, herbicides and insecticides which are injurious to the health of, farmers and consumers by using alternatives, such as Integrated Pest Management and, non-toxic biopesticides can improve health, of agricultural communities, as well as food, consumers., , •, , Changing industrial systems into those that, do not use or release toxic chemicals that, affect the health of workers and people living in the vicinity of industries can improve, health and environment., , •, , There is a need to change from using conventional energy from thermal power that, pollutes air and nuclear power that can, cause serious nuclear disasters to cleaner, and safer sources such as solar, wind and, ocean power, that do not affect human, health. Providing clean energy is an important factor that can lead to better health., , •, , The key factors are to control human population and consume less environmental, goods and services which could lead to, ‘health for all’. Unsustainable use of resources by an ever growing population leads, to unhealthy lives. Activities that go on, wasting environmental goods and destroying its services by producing large quantities of non degradable wastes, leads to, health hazards., , •, , Poverty is closely related to health and is, itself a consequence of improper environmental management. An inequitable sharing of natural resources and environmental, goods and services, is linked to poor health., , The world’s consumption of non-renewable resources is concentrated in the developed countries. Rich countries consume 50 times more per, capita than people in less developed countries., This means that developed countries also generate proportionately high quantities of waste, material, which has serious health concerns., , Definition of Health Impact Assessment, (HIA) by WHO: Health impact assessment is a, combination of procedures, methods and tools, by which a policy, program or project may be, judged as to its potential effects on the health, of a population, and the distribution of those, effects within the population., , 7.3.2 Climate and health, Human civilizations have adapted mankind to, live in a wide variety of climates. From the hot, tropics to the cold arctic, in deserts, marshlands, and in the high mountains. Both climate and, weather have a powerful impact on human life, and health issues., Natural disasters created by extremes of weather, (heavy rains, floods, hurricanes) which occur over, Human Population and the Environment, , Chapter7.p65, , 223, , 223, , 4/9/2004, 5:09 PM
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a short period of time, can severely affect health, of a community. Poor people are more vulnerable to the health impacts of climate variability, than the rich. Of approximately 80,000 deaths, which occur world-wide each year as a result of, natural disasters about 95% are in poor countries. In weather-triggered disasters hundreds of, people and animals die, homes are destroyed,, crops and other resources are lost. Public health, infrastructure, such as sewage disposal systems,, waste management, hospitals and roads are, damaged. The cyclone in Orissa in 1999 caused, 10,000 deaths. The total number of people affected was estimated at 10 to 15 million!, Human physiology can adapt to changes in, weather, within certain limits. However, marked, short-term fluctuations in weather lead to serious health issues. Heat waves cause heat-related, illness and death (e.g. heat stroke). The elderly, and persons with existing heart or respiratory, diseases are more vulnerable. Heat waves in India in 1998 were associated with many deaths., Climate plays an important role in vector-borne, diseases transmitted by insects such as mosquitoes. These disease transmitters are sensitive to, direct effects of climate such as temperature,, rainfall patterns and wind. Climate affects their, distribution and abundance through its effects, on host plants and animals., Malaria transmission is particularly sensitive to, weather and climate. Unusual weather conditions, for example a heavy downpour, can, greatly increase the mosquito population and, trigger an epidemic. In the desert and at highland fringes of malarious areas, malaria transmission is unstable and the human population, lacks inherent protective immunity. Thus, when, weather conditions (rainfall and temperature), favour transmission, serious epidemics occur in, such areas. Fluctuations in malaria over the years, have been linked to changes in rainfall associated with the El Niño cycle., , Many infectious diseases have re-emerged with, a vengeance. Loss of effective control over diseases such as malaria and tuberculosis, have led, to a return of these diseases decades after being kept under stringent control., Other diseases were not known to science earlier and seem to have suddenly hit our health, and our lives during the last few decades. AIDS,, due to the Human Immunodeficiency Virus (HIV), caused through sexual transmission and Severe, Acute Respiratory Syndrome (SARS) are two such, examples. While these cannot be directly related, to environmental change, they affect the environment in which we live by forcing a change, in lifestyles and behaviour patterns. For example, the SARS outbreak prevented people from several countries from traveling to other countries, for months, severely affecting national economies, airline companies and the tourism industry., Why have infectious diseases that were related, to our environment that were under control, suddenly made a comeback? Diseases such as, tuberculosis have been effectively treated with, anti-tubercular drugs for decades. These antibiotics are used to kill off the bacteria that causes, the disease. However nature’s evolutionary processes are capable of permitting bacteria to, mutate by creating new genetically modified, strains. Those that change in a way so that they, are not affected by the routinely used antibiotics begin to spread rapidly. This leads to a reemergence of the disease. In the case of, tuberculosis this has led to multi-drug resistant, tuberculosis. This is frequently related to HIV, which reduces an individual’s immunity to bacteria such as mycobacterium tuberculosis that, causes tuberculosis., The newer broad-spectrum antibiotics, antiseptics, disinfectants, and vaccines once thought, of as the complete answer to infectious diseases, Environmental Studies for Undergraduate Courses, , 224, , Chapter7.p65, , 7.3.3 Infectious diseases:, , 224, , 4/9/2004, 5:09 PM
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have thus failed to eradicate infectious diseases., Experts in fact now feel that these diseases will, be the greatest killers in future and not diseases, such as malignancy or heart disease., While antibiotic resistance is a well-known phenomenon there are other reasons for the reemergence of diseases. Overcrowding due to, the formation of slums in the urban setting leads, to several health hazards, including easier spread, of respiratory diseases. Inadequate drinking, water quality and poor disposal of human waste, due to absence of a closed sewage system and, poor garbage management are all urban health, issues. This has led to a comeback of diseases, such as cholera and an increased incidence of, diarrhea and dysentery as well as infectious, hepatitis (jaundice)., With increasing global warming disease patterns, will continue to change. Tropical diseases spread, by vectors such as the mosquito will undoubtedly spread malaria further away from the equator. Global warming will also change the, distribution of dengue, yellow fever, encephalitis, etc. Warmer wetter climates could cause, serious epidemics of diseases such as cholera. El, Nino which causes periodic warming is likely to, affect rodent populations. This could bring back, diseases such as the plague., , Globalisation and infectious disease, Globalization is a world-wide process which includes the internationalization of communication, trade and economic organization. It, involves parallel changes such as rapid social,, economic and political adjustments. Whilst globalization has the potential to enhance the lives, and living standards of certain population, groups, for poor and marginalized populations, in both the non-formal as well as formal economic sectors of developing countries, globalization enhances economic inequalities., , Tuberculosis (TB) kills approximately 2 million, people each year. In India the disease has reemerged and is now more difficult to treat. A, global epidemic is spreading and becoming more, lethal. The spread of HIV/AIDS and the emergence of multidrug-resistant tuberculosis is contributing to the increasing morbidity of this, disease. In 1993, the World Health Organization (WHO) declared that tuberculosis had become a global emergency. It is estimated that, between 2002 and 2020, approximately 1000, million people will be newly infected, over 150, million people will get sick, and 36 million will, die of TB – if its control is not rapidly strengthened., TB is a contagious disease that is spread through, air. Only people who are sick with pulmonary, TB are infectious. When infectious people cough,, sneeze, talk or spit, they emit the tubercle bacilli into the air. When a healthy person inhales, these, he gets infected by the disease. Symptoms include prolonged fever, coughing spells, and weight loss., It is estimated that, left untreated, each patient, of active tuberculosis will infect on an average, between 10 to 15 people every year. But people, infected with TB will not necessarily get sick with, the disease. The immune system can cause the, TB bacilli, which is protected by a thick waxy, coat, to remain dormant for years. When an, individual’s immune system is weakened, the, chances of getting active TB are greater., •, , Nearly 1% of the world’s population is, newly infected with TB each year., , •, , It is estimated that overall, one third of the, world’s population is likely to be infected, with the tuberculosis bacillus at some point, in time., , •, , Five to ten percent of people who are infected with TB (but who are not infected, , Human Population and the Environment, , Chapter7.p65, , 225, , 225, , 4/9/2004, 5:09 PM
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with HIV) become sick or infectious at some, time during their life. (WHO, 2002)., , sis is a leading cause of death among people, who are HIV-positive, accounting for about 11%, of AIDS deaths worldwide., , Factors Contributing to the rise in tuberculosis, •, , TB kills about 2 million people each year (including persons infected with HIV)., , •, , More than 8 million people become sick, with TB each year, one person in the world, every second!, , •, , About 2 million TB cases per year occur in, sub-Saharan Africa. This number is rising, rapidly as a result of the HIV/AIDS epidemic., , •, , Around 3 million TB cases per year occur in, South-east Asia., , •, , Over a quarter of a million TB cases per year, occur in Eastern Europe., , CASE STUDY, Tuberculosis in India, There are 14 million TB patients in India, account for one third of the global cases of, TB. Everyday 20,000 Indians contract TB and, more than 1,000 die due to this chronic illness. TB attacks working adults in the age, group of 15 to 50 years., , Poorly managed TB programs are threatening, to make TB incurable, Until 50 years ago, there were no drugs to cure, tuberculosis. Now, strains that are resistant to, one or more anti-TB drugs have emerged. Drugresistant tuberculosis is caused by inconsistent, or partial treatment, when patients do not take, all their drugs regularly for the required period,, when doctors or health workers prescribe inadequate treatment regimens or where the drug, supply is unreliable. From a public health perspective, poorly supervised or incomplete treatment of TB is worse than no treatment at all., When people fail to complete standard treatment regimens, or are given the wrong treatment regimen, they may remain infectious. The, bacilli in their lungs may develop resistance to, anti-TB drugs. People they infect will have the, same drug-resistant strain. While drug-resistant, TB is treatable, it requires extensive chemotherapy that is often very expensive and is also, more toxic to patients., Malaria is a life-threatening parasitic disease, transmitted by mosquitoes. The cause of malaria, a single celled parasite called plasmodium,, was discovered in 1880. Later it was found that, the parasite is transmitted from person to person through the bite of a female Anopheles, mosquito, which requires blood for the growth, of her eggs., , HIV is accelerating the spread of TB, The link between HIV and TB affects a large, number of people, each disease speeding the, other’s progress. HIV weakens the immune system. Someone who is HIV-positive and infected, with TB is many times more likely to become, seriously sick with TB rather than someone infected with TB who is HIV-negative. Tuberculo-, , Environmental Studies for Undergraduate Courses, , 226, , Chapter7.p65, , Today approximately 40% of the world’s population, mostly those living in the world’s poorest countries, risk getting malaria. The disease, was once more widespread but it was successfully eliminated from many countries with temperate climates during the mid 20th century., Today malaria has returned and is found, throughout the tropical and sub-tropical regions, , 226, , 4/9/2004, 5:09 PM
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of the world and causes more than 300 million, acute illnesses and at least one million deaths, annually (WHO)., There are several types of human malaria., Falciparum malaria is the most dangerous type, of infection and is most common in Africa south, of the Sahara, where it accounts for extremely, high mortality rates. There are also indications, of the spread of P. falciparum malaria in India, and it has reappeared in areas where it had been, eliminated., The malaria parasite enters the human host, when an infected Anopheles mosquito bites an, individual. Inside the human host, the parasite, undergoes a series of changes as part of its complex life-cycle. Its various stages allow plasmodia to evade the immune system, infect the liver, and red blood cells, and finally develop into a, form that is able to infect a mosquito again when, it bites an infected person. Inside the mosquito,, the parasite matures until it reaches the sexual, stage where it can again infect a human host, when the mosquito takes her next blood meal,, 10 or more days later., Malaria symptoms appear about 9 to 14 days, after the mosquito bite, although this varies with, different plasmodium species. Malaria produces, high fever, headache, vomiting and body ache., If drugs are not available for treatment, or the, parasites are resistant to them, the infection can, progress rapidly to become life-threatening., Malaria can kill by infecting and destroying red, blood cells (anaemia) and by clogging the capillaries that carry blood to the brain (cerebral malaria) or other vital organs., Malaria parasites are developing unacceptable, levels of resistance to drugs. Besides this, many, insecticides are no longer useful against mosquitoes transmitting the disease. Good environmental management by clearing pools of, stagnant water during the monsoons is effective in reducing the number of mosquitoes., , Mosquito nets treated with insecticide reduce, malaria transmission and child deaths. Prevention of malaria in pregnant women, through, measures such as Intermittent Preventive Treatment and the use of insecticide-treated nets, (ITNs), results in improvement in maternal health,, as well as infant health and survival. Prompt, access to treatment with effective up-to-date, medicines, such as artemisinin-based combination therapies (ACTs), saves lives. If countries can, apply these and other measures on a wide scale, and monitor them carefully, the burden of malaria on society will be significantly reduced., , 7.3.4 Water-related diseases, , Water Supply, sanitation and hygiene development, Among the main problems are a lack of priority, given to this sector, lack of financial resources,, erratic water supply and sanitation services, poor, hygiene related behaviour patterns, and inadequate sanitation in public places such as, schools, hotels, hospitals, health centers, etc., One of the most important aspects is a lack of, environmental education and awareness that, these disease processes are related to poor environment management in various sectors., Providing access to sufficient quantities of safe, water, the provision of facilities for a sanitary, disposal of excreta, and introducing sound hygiene related behaviour can reduce the morbidity and mortality caused by these risk factors., , Environmental Sanitation and Hygiene Development, About 2.4 billion people globally live under highly, unsanitary conditions. Poor hygiene and, behaviour pattern increase the exposure to risk, of incidence and spread of infectious diseases., Water improperly stored in homes is frequently, , Human Population and the Environment, , Chapter7.p65, , 227, , 227, , 4/9/2004, 5:09 PM
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contaminated by inadequate management at, the household level. This can be easily reduced, through education and awareness of how, waterborne diseases are transmitted., , Health and Water Resources Development, An important aspect related to water-related, diseases (in particular: water-related vectorborne diseases) is attributable to the way water, resources are developed and managed. In many, parts of the world the adverse health impacts, of dam construction, irrigation development and, flood control is related to increased incidence, of malaria, Japanese encephalitis, schistosomiasis, lymphatic filariasis and other conditions., Other health issues indirectly associated with, water resources development include nutritional, status, exposure to agricultural pesticides and, their residues., , Water borne diseases, Arid areas with rapidly expanding populations, are already facing a crisis over water. Conservation of water and better management is an urgent need. The demand and supply balance is a, vital part of developing sustainable use of water. This is being termed the ‘Blue Revolution’, and needs Governments, NGOs and people to, work together towards a better water policy at, International, National, State, regional and local levels. Locally good watershed management, is a key to solving local rural problems. Present, patterns of development are water hungry and, water wasters. They do not address pollution, and overuse. The linkages between managing, water resources and health issues are have not, been prioritised as a major source of environmental problems that require policy change,, administrative capacity building and an increased, financial support., , There are 4 major types of water related, diseases:, 1. Water borne diseases:, These are caused by dirty water contaminated by human and animal wastes, especially from urban sewage, or by chemical, wastes from industry and agriculture. Some, of these diseases, such as cholera and typhoid, cause serious epidemics. Diarrhoea,, dysentery, polio, meningitis, and hepatitis A, and E, are caused due to improper drinking, water. Excessive levels of nitrates cause blood, disorders when they pollute water sources., Pesticides entering drinking water in rural, areas cause cancer, neurological diseases and, infertility. Improving sanitation and providing treated drinking water reduces the incidence of these diseases., 2. Water based diseases:, Aquatic organisms that live a part of their, life cycle in water and another part as a, parasite in man, lead to several diseases. In, India, guinea worm affects the feet. Round, worms live in the small intestine, especially, of children., 3. Water related vector diseases:, Insects such as mosquitoes that breed in, stagnant water spread diseases such as, malaria and filariasis. Malaria that was effectively controlled in India, has now come, back as the mosquitoes have become resistant to insecticides. In addition, anti-malarial, drugs are now unable to kill the parasites, as they have become resistant to drugs., Change in climate is leading to the formation of new breeding sites. Other vector, born diseases in India include dengue fever, and filariasis. Dengue fever carries a high, mortality. Filariasis leads to fever and chronic, swelling over the legs., Eliminating mosquito breeding sites when, pooling of water occurs in the monsoon,, Environmental Studies for Undergraduate Courses, , 228, , Chapter7.p65, , 228, , 4/9/2004, 5:09 PM
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using fish to control mosquito larval populations, are ways to reduce these diseases, without using toxic insecticides that have ill, effects on human health., 4. Water scarcity diseases:, In areas where water and sanitation is poor,, there is a high incidence of diseases such as, tuberculosis, leprosy, tetanus, etc. which, occur when hands are not adequately, washed., Arsenic in drinking water: Arsenic in drinking-water is a serious hazard to human health., It has attracted much attention since its recognition in the 1990s of its wide occurrence in wellwater in Bangladesh. It occurs less frequently in, most other countries. The main source of arsenic in drinking water is arsenic-rich rocks, through which the water has filtered. It may also, occur because of mining or industrial activity in, some areas. WHO has worked with other UN, organizations to produce a state-of-the-art review on arsenic in drinking water., , Drinking water that is rich in arsenic leads to, arsenic poisoning or arsenicosis. Excessive concentrations are known to occur in some areas., The health effects are generally delayed and the, most effective preventive measure is supplying, drinking water which is free of arsenic. Arsenic, contamination of water is also due to industrial, processes such as those involved in mining, metal, refining, and timber treatment. Malnutrition, may aggravate the effects of arsenic on blood, vessels., Water with high concentrations of arsenic if used, over 5 to 20 years, results in problems such as, colour changes on the skin, hard patches on the, palms and soles, skin cancer, cancers of the bladder, kidney and lung, and diseases of the blood, vessels of the legs and feet. It may also lead to, diabetes, high blood pressure and reproductive, disorders., Natural arsenic contamination occurs in Argentina, Bangladesh, Chile, China, India, Mexico,, Thailand and the United States. In China (in the, Province of Taiwan) exposure to arsenic leads, to gangrene, known as ‘black foot disease’., Long term solutions for prevention of arsenicosis, is based on providing safe drinking-water:, , CASE STUDIES, Arsenic poisoning – Bangladesh, , •, , More than half the population of Bangladesh, is threatened by high levels of arsenic found, in drinking water. This could eventually lead, to an epidemic of cancers and other fatal, diseases., , Deeper wells are often less likely to be contaminated., , •, , Testing of water for levels of arsenic and, informing users., , •, , Rezaul Morol, a young Bangladeshi man,, nearly died from arsenic poisoning caused, by drinking arsenic-laden well-water for several years. The doctor advised Rezaul to stop, drinking contaminated water and eat more, protein-rich food such as fish. Since then, Rezaul feels a lot better and is happy that, his skin is healing., , Monitoring by health workers - people need, to be checked for early signs of arsenicosis, - usually by observing skin problems in areas where arsenic in known to occur., , •, , Health education regarding harmful effects, of arsenicosis and how to avoid them., , Human Population and the Environment, , Chapter7.p65, , 229, , 229, , 4/9/2004, 5:09 PM
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Diarrhoea, Though several types of diarrhoea which give, rise to loose motions and dehydration occur all, over the world, this is especially frequently observed in developing countries. It causes 4% of, all deaths. In another 5% it leads to loss of, health. It is caused by gastrointestinal infections, which kill around 2.2 million people globally each, year. Most of these are children in developing, countries. The use of contaminated water is an, important cause of this group of conditions., Cholera and dysentery cause severe, sometimes, life threatening and epidemic forms of these, diseases., , Effects on health: Diarrhoea is the frequent passage of loose or liquid stools. It is a symptom of, various gastrointestinal infections. Depending on, the type of infection, the diarrhoea may be watery (for example in cholera caused by vibrio, cholera) or passed with blood and mucous (in, dysentery caused by an amoeba, E Histolitica)., Depending on the type of infection, it may last, a few days, or several weeks. Severe diarrhoea, can become life threatening due to loss of excessive fluid and electrolytes such as Sodium and, Potassium in watery diarrhoea. This is particularly fatal in infants and young children. It is also, dangerous in malnourished individuals and, people with poor immunity., The impact of repeated diarrhoea on nutritional, status is linked in a vicious cycle in children., Chemical or non-infectious intestinal conditions, can also result in diarrhoea., , Causes of diarrhoea: Diarrhoea is caused by several bacterial, viral and parasitic organisms. They, are mostly spread by contaminated water. It is, more common when there is a shortage of clean, water for drinking, cooking and cleaning. Basic, hygiene is important in its prevention., , Diarrhoea is spread from one individual to another due to poor personal hygiene. Food is a, major cause of diarrhoea when it is prepared or, stored in unhygienic conditions. Water can contaminate food such as vegetables during irrigation. Fish and seafood from polluted water is a, cause of severe diarrhoea., The infectious agents that cause diarrhoea are, present in our environment. In developed countries where good sanitation is available, most, people get enough safe drinking water. Good, personal and domestic hygiene prevents this, disease which is predominantly seen in the developing world. About 1 billion people do not, have access to clean water sources and 2.4, billion have no basic sanitation (WHO website)., In Southeast Asia, diarrhoea is responsible for, 8.5% of all deaths. In 1998, diarrhoea was, estimated to have killed 2.2 million people, most, of whom were under 5 years of age (WHO,, 2000)., , Interventions: Key measures to reduce the number of cases of diarrhoea include:, •, , Access to safe drinking water., , •, , Improved sanitation., , •, , Good personal and food hygiene., , •, , Health education about how these infections, spread., , Environmental Studies for Undergraduate Courses, , 230, , Chapter7.p65, , Water contaminated with human feces surrounding a rural water source, or from municipal sewage, septic tanks and latrines in urban, centers, are important factors in the spread of, these diseases. Feces of domestic animals also, contain microorganisms that can cause diarrhoea through water., , 230, , 4/9/2004, 5:09 PM
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Key measures to treat diarrhoea include:, •, , Giving more fluids than usual, (oral rehydration) with salt and sugar, to prevent dehydration., , •, , Continue feeding., , •, , Consulting a health worker if there are signs, of dehydration or other problems., , In rural India, during the last decade public education through posters and other types of communication strategies has decreased infant, mortality due to diarrhoea in several States. Posters depicting a child with diarrhoea being given, water, salt and sugar solution to reduce death, from dehydration has gone a long way in reducing both a serious condition requiring, hospitalisation and intravenous fluids, as well as, mortality., , While cholera has devastated much of Asia and, Africa for years, its reintroduction for the first, time in almost a century on the South American continent in 1991 is an example of a well, recognised infectious disease re-emerging in a, region after decades. While cholera is often, waterborne, many foods also transmit infection., In Latin America, ice and raw or underprocessed, seafood are important causes for cholera transmission., Infection with a specific type of Escherichia coli, (E. coli) was first described in 1982. Subsequently, it has emerged rapidly as a major cause, of bloody diarrhoea and acute renal failure. The, infection is sometimes fatal, particularly in children. Outbreaks of infection, generally associated with beef, have been reported in Australia,, Canada, Japan, United States, in various European countries, and in southern Africa. Outbreaks have also implicated alfalfa sprouts,, unpasteurized fruit juice, lettuce, game meat, (meat of wild animals) and cheese curd., , 7.3.5 Risks due to chemicals in food, Food contaminated by chemicals is a major, worldwide public health concern. Contamination may occur through environmental pollution, of the air, water and soil. Toxic metals, PCBs, and dioxins, or the intentional use of various, chemicals, such as pesticides, animal drugs and, other agrochemicals have serious consequences, on human health. Food additives and contaminants used during food manufacture and processing adversely affects health., , Diseases spread by food: Some foodborne diseases though well recognized, have recently, become more common. For example, outbreaks, of salmonellosis which have been reported for, decades, has increased within the last 25 years., In the Western hemisphere and in Europe, Salmonella serotype Enteritidis (SE) has become a, predominant strain. Investigations of SE outbreaks indicate that its emergence is largely related to consumption of poultry or eggs., , In 1996, an outbreak of Escherichia coli in Japan affected over 6,300 school children and, resulted in 2 deaths., , Listeria monocytogenes (Lm): The role of food, in the transmission of this condition has been, recognized recently. In pregnant women, infections with Lm causes abortion and stillbirth. In, infants and persons with a poor immune system it may lead to septicemia (blood poisoning), and meningitis. The disease is most often associated with consumption of foods such as soft, cheese and processed meat products that are, kept refrigerated for a long time, because Lm, can grow at low temperatures. Outbreaks of, listeriosis have been reported from many countries, including Australia, Switzerland, France, and the United States. Two recent outbreaks of, Listeria monocytogenes in France in 2000 and, in the USA in 1999 were caused by contaminated pork tongue and hot dogs respectively., , Human Population and the Environment, , Chapter7.p65, , 231, , 231, , 4/9/2004, 5:09 PM
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Foodborne trematodes (worms) are increasing, in South-east Asia and Latin America. This is, related to a combination of intensive aquaculture production in unsanitary conditions, and, consumption of raw or lightly processed fresh, water fish and fishery products. Foodborne, trematodes can cause acute liver disease, and, may lead to liver cancer. It is estimated that 40, million people are affected worldwide., Bovine Spongiform Encephalopathy (BSE), is a, fatal, transmittable, neurodegenerative disease, of cattle. It was first discovered in the United, Kingdom in 1985. The cause of the disease was, traced to an agent in sheep, which contaminated recycled bovine carcasses used to make, meat and bone meal additives for cattle feed., Recycling of the BSE agent developed into a, common source epidemic of more than 180,000, diseased animals in the UK alone. The agent, affects the brain and spinal cord of cattle which, produces sponge-like changes visible under a, microscope. About 19 countries have reported, BSE cases and the disease is no longer confined, to the European Community. A case of BSE has, been reported in a cattle herd in Japan., In human populations, exposure to the BSE, agent (probably in contaminated bovine-based, food products) has been strongly linked to the, appearance in 1996 of a new transmissible, spongiform encephalopathy of humans called, variant Creutzfeldt-Jakob Disease (vCJD). By, January 2002, 119 people developed vCJD, most, from the UK but five cases have been reported, from France., , 7.3.6 Cancer and environment, Cancer is caused by the uncontrolled growth, and spread of abnormal cells that may affect, almost any tissue of the body. Lung, colon, rectal and stomach cancer are among the five most, common cancers in the world for both men and, women. Among men, lung and stomach can-, , More than 10 million people are diagnosed with, cancer in the world every year. It is estimated, that there will be 15 million new cases every, year by 2020. Cancer causes 6 million deaths, every year – or 12% of deaths worldwide., The causes of several cancers are known. Thus, prevention of at least one-third of all cancers is, possible. Cancer is preventable by stopping, smoking, providing healthy food and avoiding, exposure to cancer-causing agents (carcinogens). Early detection and effective treatment, is possible for a further one-third of cases. Most, of the common cancers are curable by a combination of surgery, chemotherapy (drugs) or radiotherapy (X-rays). The chance of cure increases, if cancer is detected early., Cancer control is based on the prevention and, control of cancer by:, •, , Promotion and strengthening of comprehensive national cancer control programs., , •, , Building international networks and partnerships for cancer control., , •, , Promotion of organized, evidence-based, interventions for early detection of cervical, and breast cancer., , •, , Development of guidelines on disease and, program management., , •, , Advocacy for a rational approach to effective treatments for potentially curable, tumours., , Environmental Studies for Undergraduate Courses, , 232, , Chapter7.p65, , cer are the most common cancers worldwide., For women, the most common cancers are, breast and cervical cancer. In India, oral and, pharangeal cancers form the most common type, of cancer which are related to tobacco chewing., , 232, , 4/9/2004, 5:09 PM
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•, , Support for low-cost approaches to respond, to global needs for pain relief and palliative, care., , Prevention of cancer: Tobacco smoking is the, single largest preventable cause of cancer in the, world. It causes 80 to 90% of all lung cancer, deaths. Another 30% of all cancer deaths, especially in developing countries include deaths, from cancer of the oral cavity, larynx, oesophagus and stomach which are related to tobacco, chewing. Preventive measures include bans on, tobacco advertising and sponsorship, increased, tax on tobacco products, and educational programs which are undertaken to reduce tobacco, consumption., Dietary modification is an important approach, to cancer control. Overweight individuals and, obesity are known to be associated with cancer, of the oesophagus, colon, rectum, breast, uterus, and kidney. Fruit and vegetables may have a, protective effect against many cancers. Excess, consumption of red and preserved meat may, be associated with an increased risk of colorectal, cancer., Infectious agents are linked with 22% of cancer deaths in developing countries and 6% in, industrialized countries. Viral hepatitis B and C, cause cancer of the liver. Human papilloma virus infection causes cancer of the cervix. The, bacterium Helicobacter pylori increases the risk, of stomach cancer. In some countries the parasitic infection schistosomiasis increases the risk, of bladder cancer. Liver fluke increases the risk, of cancer of the bile ducts. Preventive measures, include vaccination and prevention of infection., Excessive solar ultraviolet radiation increases the, risk of all types of cancer of the skin. Avoiding, excessive exposure to the sun, use of sunscreens, and protective clothing are effective preventive, measures. Asbestos is known to cause lung cancer. Aniline dyes have been linked to bladder, cancer. Benzene can lead to leukaemia (blood, cancer). The prevention of certain occupational, , and environmental exposure to several chemicals is an important element in preventing cancer., , 7.4 HUMAN RIGHTS, Several environmental issues are closely linked, to human rights. These include the equitable, distribution of environmental resources, the, utilisation of resources and Intellectual Property, Rights (IPRs), conflicts between people and wildlife especially around PAs, resettlement issues, around development projects such as dams and, mines, and access to health to prevent environment related diseases., , 7.4.1 Equity, One of the primary concerns in environmental, issues is how wealth, resources and energy must, be distributed in a community. We can think of, the global community, regional community issues, national concerns and those related to a, family or at the individual level. While economic, disparities remain a fact of life, we as citizens of, a community must appreciate that a widening, gap between the rich and the poor, between, men and women, or between the present and, future generations must be minimised if social, justice is to be achieved. Today the difference, between the economically developed world and, the developing countries is unacceptably high., The access to a better lifestyle for men as against, women is inherent in many cultures. Last but, not the least, we in the present generation cannot greedily use up all our resources leaving future generations increasingly impoverished., Rights to land, water, food, housing are all a, part of our environment that we all share. However, while some live unsustainable lifestyles with, consumption patterns that the resource base, cannot support, many others live well below the, poverty line. Even in a developing country such, as ours, there are enormous economic inequali-, , Human Population and the Environment, , Chapter7.p65, , 233, , 233, , 4/9/2004, 5:09 PM
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ties. This requires an ethic in which an equitable, distribution becomes a part of everyone’s thinking. The people who live in the countries of the, North and the rich from the countries in the, South will have to take steps to reduce their, resource use and the waste they generate. Both, the better off sectors of society and the less fortunate need to develop their own strategies of, sustainable living and communities at each level, must bring about more equitable patterns of, wealth., , dams, mining and Protected Areas. Movements, to protect the rights of indigenous peoples are, growing worldwide. Reversing actions that have, already been taken decades ago is a complex, problem that has no simple solutions. In many, cases a just tradeoff is at best achieved through, careful and sensitively managed negotiations., This needs a deep appreciation of local environmental concerns as well as a sensitivity to the, rights of local people., , The right to the use of natural resources that, the environment holds is an essential component of human rights. It is related to disparities, in the amount of resources available to different sectors of society. People who live in wilderness communities are referred to as ecosystem, people. They collect food, fuelwood, and nonwood products, fish in aquatic ecosystems, or, hunt for food in forests and grasslands. When, landuse patterns change from natural ecosystems to more intensively used farmland and, pastureland the rights of these indigenous, people are usually sacrificed. Take the case of, subsidies given to the pulp and paper industry, for bamboo which makes it several times, cheaper for the industry than for a rural individual who uses it to build his home. This infringes on the human right to collect resources, they have traditionally used free of cost. Another issue is the rights of small traditional fishermen who have to contend against mechanised, trawlers that impoverish their catch and overharvest fish in the marine environment. These, people’s right to a livelihood conflicts with the, powerful economic interests of large-scale, organised fisheries., , 7.4.2 Nutrition, health and human rights, , There are serious conflicts between the rights, of rural communities for even basic resources, such as water, and industrial development which, requires large amounts of water for sustaining, its productivity. The right to land or common, property resources of tribal people is infringed, upon by large development projects such as, , Nutrition affects and defines the health status, of all people, rich and poor. It is linked to the, way we grow, develop, work, play, resist infection and reach our aspirations as individuals,, communities and societies. Malnutrition makes, people more vulnerable to disease and premature death. Poverty is a major cause as well as a, consequence of ill-health. Poverty, hunger, malnutrition and poorly managed environments, together affect health and weaken the socioeconomic development of a country. Nearly, 30% of humanity, especially those in developing countries – infants, children, adolescents,, adults, and older persons are affected by this, problem. A human rights approach is needed, to appreciate and support millions of people left, behind in the 20th century’s health revolution., We must ensure that our environmental, values and our vision are linked to human rights, and create laws to support those that need a, better environment, better health and a better, lifestyle., Environmental Studies for Undergraduate Courses, , 234, , Chapter7.p65, , There are links between environment, nutrition, and health which must be seen from a humanrights perspective. Proper nutrition and health, are fundamental human rights. The right to life, is a Fundamental Right in our constitution. As a, deteriorating environment shortens life spans,, this in effect has an impact on our fundamental, constitutional right., , 234, , 4/9/2004, 5:09 PM
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Health and sustainable human development are, equity issues. In our globalized 21st century,, equity must begin at the bottom, hand in hand, with a healthy environment, improved nutrition,, and sustainable lifestyles. Putting first things first,, we must also realize that resources allocated to, preventing and eliminating disease will be effective only if the underlying causes such as, malnutrition and environmental concerns, as, well as their consequences, are successfully addressed., , 7.4.3 Intellectual Property Rights and Community Biodiversity Registers, Traditional people, especially tribals living in forests, have used local plants and animals for generations. This storehouse of knowledge leads to, many new ‘discoveries’ for modern pharmaceutical products. The revenue generated from such, ‘finds’ goes to the pharmaceutical industry that, has done the research and patented the product. This leaves the original tribal user with nothing while the industry could earn billions of, rupees. To protect the rights of indigenous, people who have used these products, a possible tool is to create a Community Biodiversity, Register of local products and their uses so that, its exploitation by the pharmaceutical industry, would have to pay a royalty to the local community. This however has still not been generally accepted. Mechanisms have to be worked, out so that the local traditional users rights are, protected., , Traditional Medicine: Traditional medicine refers, to health practices, approaches, knowledge and, beliefs that incorporate plant, animal and mineral based medicines, frequently of local or regional origin. It may be linked to spiritual, therapies, manual techniques and exercises., These may be used singly or in combination to, treat, diagnose and prevent illnesses or maintain well-being. Traditional medicine is often, handed down through the generations or, , may be known to a special caste or tribal, group., Traditional medicine has maintained its popularity in all regions of the developing world and, its use is rapidly spreading in industrialized countries. In India, some of our primary health care, needs are taken care of entirely by traditional, medicine, while in Africa, up to 80% of the, population uses it for primary health care. In, industrialized countries, adaptations of traditional medicine are termed “Complementary“, or “Alternative” Medicine (CAM)., While there are advantages to traditional medicine as it is cheap and locally available, there, are diseases which it cannot treat effectively., This is a risk, as patients who use these alternative medicinal practices may rely on an ineffective measure. The consequences could be a, serious delay in diagnosis and effective treatment of a treatable condition. There is a need, to carefully research the claims of traditional, practices to ensure that they are effective., In addition to patient safety issues, there is the, risk that a growing herbal market and its great, commercial benefit poses a threat to biodiversity, through the over harvesting of the raw material, for herbal medicines and other natural health, care products. This has been observed in the, case of several Himalayan plants. If extraction, from the wild is not controlled, this can lead to, the extinction of endangered plant species and, the destruction of natural habitats of several, species., Another related issue is that at present, the requirements for protection provided under international standards for patent law and by most, national conventional patent laws are inadequate to protect traditional knowledge and, biodiversity., There are tried and tested scientific methods and, products that have their origins in different tra-, , Human Population and the Environment, , Chapter7.p65, , 235, , 235, , 4/9/2004, 5:09 PM
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CASE STUDY, , to our destruction of our environment. The problems that are created by technology and economic growth are a result of our improper, thinking on what ‘development’ means. Since, we still put a high value only on economic, growth, we have no concern for aspects such, as sustainability or equitable use of resources., This mindset must change before concepts such, as sustainable development can be acted upon., , A US company was granted a patent for discovering extracts of arhar (pigeon pea or, Cajanus cajan) in the treatment of diabetes,, hypoglycemia, obesity and blockage of arteries. The use of pigeon pea extracts in India is well known. CSIR has challenged this, patent as it infringes on India’s traditional, knowledge, although challenging the patent, is difficult, as India’s scientific documentation of its traditional knowledge is quite poor., , Unsustainable development is a part of economic growth of the powerful while it makes, the poor poorer. Consumerism is one aspect of, this process favoured by the rich. As consumption of resources has till recently been an index, of development, consumerism has thrived. It is, only recently that the world has come to realise, that there are other more important environmental values that are essential to bring about, a better way of life., , ditional medicinal methods. Twenty-five percent, of modern medicines are made from plants first, used traditionally. Yoga is known to reduce, asthma attacks. Traditional Medicine has been, found to be effective against several infectious, diseases., , Over one-third of the population in developing, countries lack access to essential allopathic medicines. The provision of safe and effective TM/, CAM therapies could become a tool to increase, access to health care., , 7.5 VALUE EDUCATION, Value education in the context of our environment is expected to bring about a new sustainable way of life. Education both through formal, and non-formal processes must thus address understanding environmental values, valuing nature and cultures, social justice, human heritage,, equitable use of resources, managing common, property resources and appreciating the cause, of ecological degradation., Essentially, environmental values cannot be, taught. They are inculcated through a complex, process of appreciating our environmental assets and experiencing the problems caused due, , What are values?, Values deal with ones own principles and, standards from which we judge what is right, and wrong behaviour., , Environmental Studies for Undergraduate Courses, , 236, , Chapter7.p65, , Values in environment education must bring in, several new concepts. Why and how can we, use less resources and energy? Why do we need, to keep our surroundings clean? Why should, we use less fertilisers and pesticides in farms?, Why is it important for us to save water and, keep our water sources clean? Or separate our, garbage into degradable and non-degradable, types before disposal? All these issues are linked, to the quality of human life and go beyond, simple economic growth. They deal with a love, and respect for nature. These are the values that, will bring about a better humanity, one in which, we can live healthy, productive and happy lives, in harmony with nature., , 236, , 4/9/2004, 5:09 PM
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7.5.1 Environmental Values:, Every human being has a great variety of feelings for different aspects of his or her surroundings. The Western, modern approach values the, resources of Nature for their utilitarian importance alone. However true environmental values go beyond valuing a river for its water, a, forest for its timber and non-wood forest products, or the sea for its fish. Environmental values are inherent in feelings that bring about a, sensitivity for preserving nature as a whole. This, is a more spiritual, Eastern traditional value., There are several writings and sayings in Indian, thought that support the concept of the oneness of all creation, of respecting and valuing, all the different components of Nature. Our, environmental values must translate to pro conservation actions in all our day to day activities., Most of our actions have adverse environmental impacts unless we consciously avoid them., The sentiment that attempts to reverse these, trends is enshrined in our environmental values., , Values lead to a process of decision making, which leads to action. For value education, in relation to the environment, this process, is learned through an understanding and appreciation of Nature’s oneness and the importance of its conservation., , Humans have an inborn desire to explore Nature. Wanting to unravel its mysteries is a part, of human nature. However, modern society and, educational processes have invariably suppressed these innate sentiments. Once exposed, to the wonders of the wilderness, people tend, to bond closely to Nature. They begin to appreciate its complexity and fragility and this awakens a new desire to want to protect our natural, heritage. This feeling for Nature is a part of our, Constitution, which strongly emphasises this, value., , Concepts of what constitutes right and wrong, behaviour changes with time. Values are not, constant. It was once considered ‘sport’ to shoot, animals. It was considered a royal, brave and, much desirable activity to kill a tiger. In today’s, context, with wildlife reduced to a tiny fraction, of what there was in the past, it is now looked, down upon as a crime against biodiversty conservation. Thus the value system has been altered with time. Similarly with the large tracts, of forest that existed in the past, cutting a few, trees was not a significant criminal act. Today, this constitutes a major concern. We need a, strong new environmental value system in which, felling trees is considered unwise behaviour., With the small human numbers in the past,, throwing away a little household degradable, garbage could not have been considered wrong., But with enormous numbers of people throwing away large quantities of non-degradable, waste, it is indeed extremely damaging to the, environment and our value system must prevent this through a strong environmental value, education system., Appreciating the negative effects of our actions, on the environment must become a part of our, day to day thinking. Our current value system, extols economic and technical progress as being what we need in our developing country., Environmental values based on the Constitution of India, Article 48A:, “The state shall endeavour to protect and, improve the environment and to safeguard, the forests and wildlife in the country.”, Article 51A (g), The constitution expects that each citizen of, the country must “protect and improve the, natural environment, including forests, lakes,, rivers and wildlife, and to have compassion, for all living creatures.”, , Human Population and the Environment, , Chapter7.p65, , 237, , 237, , 4/9/2004, 5:09 PM
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While we do need economic development, our, value system must change to one that makes, people everywhere support a sustainable form, of development so that we do not have to bear, the cost of environmental degradation., Environmental problems created by development are due neither to the need for economic, development, nor to the technology that produces pollution, but rather to a lack of awareness of the consequences of unlimited and, unrestrained anti-environmental behaviour., Looked at in this way, it deals with concepts of, what is appropriate behaviour in relation to, our surroundings and to other species on Earth., How we live our lives in fact shapes our, environment. This is what environmental values, are about., Each action by an individual must be linked to, its environmental consequences in his/her mind, so that a value is created that leads to strengthening pro-environmental behaviour and preventing anti-environmental actions. This cannot, happen unless new educational processes are, created that provide a meaning to what is taught, at school and college level. Every small child, while growing up asks questions like ‘What does, this mean?’. They want an explanation for things, happening around them that can help them, make decisions and through this process develop, values. It is this innate curiosity that leads to a, personalized set of values in later life. Providing, appropriate ‘meanings’ for such questions related to our own environment brings in a set of, values that most people in society begin to accept as a norm. Thus pro environmental actions, begin to move from the domain of individuals, to that of a community., At the community level, this occurs only when a, critical number of people become environmentally conscious so that they constitute a proenvironment lobby force that makes governments and other people accept good environ-, , I will work towards the protection of our environment and the preservation of our wild, species,, I will work towards this with other like, minded individuals., I will consciously avoid committing acts that, damage our environment and will publicly, assert my dislikes for acts against the environment., I will not permit others to cause harm to the, wilderness and our wild species without protest., I will use resources carefully by reducing, reusing and recycling whatever I use such as, water, paper, plastic, metal and glass articles., I will not carelessly throw away items that, are made of our precious natural resources., I will use energy carefully and close off electrical appliances when not in use., I will not waste energy by using a fuel based, vehicle when I can walk or cycle., I will visit our wondrous wild places with clean, air, water, soil, and all their plants and animals, and become party to their conservation., I will not permit any individual or Government action spoil our environment or damage wilderness without protest., I will always care for Mother Earth., I will try not to damage her knowingly or, unknowingly., , mental behaviour as an important part of development., What professions require making value judgements that greatly influence our environment?, Evidentally nearly every profession can and does, influence our environment, but some do so more, than others. Policy makers, administrators,, landuse planners, media, architects, medical, personnel, health care workers, agriculturalists,, Environmental Studies for Undergraduate Courses, , 238, , Chapter7.p65, , Strategies for sustainable living, , 238, , 4/9/2004, 5:09 PM
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agricultural experts, irrigation planners, mining, experts, foresters, forest planners, industrialists, and, most importantly, teachers at school and, college level, are all closely related to pro environmental outcomes., Environmental values have linkages to varied, environmental concerns. While we value resources that we use as food, water and other, products, there are also environmental services, that we must appreciate. These include Nature’s, mechanisms in cleaning up air by removing carbon dioxide and adding oxygen by plant life,, recycling water through the water cycle of nature, maintaining climate regimes, etc., But there are other aesthetic, ethical values that, are equally important aspects of our environment that we do not appreciate consciously., While every species is of importance in the web, of life, there are some which man has come to, admire for their beauty alone. The tiger’s magnificence, the whale and elephant’s giant size,, the intelligence of our cousins the primates, the, graceful flight of a flock of cranes, are parts of, nature that we cannot help but admire. The lush, splendor of an evergreen forest, the great power, of the ocean’s waves, and the tranquility of the, Himalayan mountains are things that each of, us values even if we do not experience it ourselves. We value its being there on Earth for us., This is called its ‘existance value’. The list of, wondrous aspects of Nature’s intricate connections is indeed awe-inspiring. This is also a part, of our environment that we must value for its, own sake. This is the oneness of Nature., We must equally look at our environment beyond the wild sphere. There is incredible beauty, in some man-modified landscapes, the coloured, patterns of farmland or the greens of a tea or, coffee plantation in the hills., Urban gardens and open space are also valuable and thus must be of prime concern to urban planners. These green spaces act as not only, , the lungs of a city, but also provide much needed, psychological support. The mental peace and, relaxation provided by such areas needs to be, valued, although it is difficult to put a price tag, on these values. Nevertheless, these centers of, peace and tranquility give urban dwellers an, opportunity to balance their highly man-modified environments with the splash of green of a, garden space., Environmental values must also stress on the, importance of preserving ancient structures. The, characteristic architecture, sculpture, artworks, and crafts of ancient cultures is an invaluable, environmental asset. It tells us where we have, come from, where we are now, and perhaps, where we should go. Architectural heritage goes, beyond preserving old buildings, to conserving, whole traditional landscapes in rural areas and, streetscapes in urban settings. Unless we learn, to value these landscapes, they will disappear, and our heritage will be lost., As environmentally conscious individuals we, need to develop a sense of values that are linked, with a better and more sustainable way of life, for all people. There are several positive as well, as negative aspects of behavior that are linked, to our environment. The positive feelings that, support environment include a value for Nature,, cultures, heritage, and equity. We also need to, become more sensitive to aspects that have, negative impacts on the environment. These, include our attitude towards degradation of the, environment, loss of species, pollution, poverty,, corruption in environmental management, the, rights of future generations and animal rights., Several great philosophers have thoughts that, have been based on, or embedded, in pro environmental behavior. Mahatma Gandhi and, Rabindranath Tagore are among the many internationally well-known scholars whose, thought have included values that are related, to environmental consciousness. We need to, appreciate these values to bring about a better, , Human Population and the Environment, , Chapter7.p65, , 239, , 239, , 4/9/2004, 5:09 PM
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way of life on earth for all people and all living, creatures., , 7.5.2 Valuing Nature:, The most fundamental environmental sentiment, is to value Nature herself. Appreciating Her, magnificence and treasuring life itself leads to, positive feelings that are a manifestation of pro, environmental consciousness. The one-ness of, our lives with the rest of nature and a feeling, that we are only a miniscule part of nature’s, complex web of life becomes apparent, when, we begin to appreciate the wonders of nature’s, diversity. We must appreciate that we belong, to a global community that includes another 1.8, million known living forms. Nothing makes us, more conscious of this wonderous aspect of our, earth’s diversity than a walk through the wilderness, feeling and exploring its beauty and, experiencing its infinite variety. The tiny creatures that live complex lives and the towering, trees are all a part of this phenomenon we call, ‘life’. Today, man does not even know if other, complex forms of life exist outside our own solar system in distant space. We may be alone in, space or may be accompanied by other, completely different, living forms. But for now we, only know for sure that the Earth’s life forms, are unique. We thus have a great responsibility, to protect life in all its glorious forms and must, therefore respect the wilderness with all its living creatures, where man’s own hand has not, created changes that have led to perturbing, natural habitats. We need to develop a sense of, values that lead us to protect what is left of the, wilderness by creating effective National Parks, and Wildlife Sanctuaries. However this cannot, be done to the detriment of the millions of tribal, or indigenous people who live in wilderness ecosystems. There are thus conflicting values that, need to be balanced carefully. On the one hand, we need to protect natural ecosystems, while, on the other, we must protect the rights of local people., , In the 1970s a new thinking on environmental concerns began to emerge, protecting, nature and the wilderness for its own sake,, which is now referred to as ‘Deep Ecology’., It was fostered by the thinking of Arne Naess,, a Norwegian professor of Philosophy and a, great believer in Gandhian thinking and Buddhism. It recognises the intrinsic value of all, living beings and looks upon mankind as a, small segment of a great living community, of life forms. It teaches that the wellbeing, and flourishing of human and non-human, life on Earth have value in themselves and, that these values are independent of the, usefulness of the non-human world for human purposes., , Yet apart from valuing the diversity of life itself,, we must also learn to value and respect diverse, human cultures. Many of the tribal cultures of, our country are vanishing because those with, more dominant and economically advanced, ways of life do not respect their lifestyles, that, are in fact closer to nature and frequently more, sustainable. We believe that our modern technology-based lifestyles are the sole way for society to progress. Yet this is only a single, dimension of life that is based on economic, growth., While currently the environmental movement, focuses on issues that are concerned with the, management of the natural environment for the, ‘benefit’ of man, Deep Ecology promotes an, approach that is expected to bring about a more, appropriate ecological balance on Earth and is, akin to a spiritual approach to Nature. This has, great long-term implications not only for humans, but for the whole of Nature., For example some environmentalists emphasise, the need to preserve wilderness for its aesthetic, Environmental Studies for Undergraduate Courses, , 240, , Chapter7.p65, , Deep ecology, , 240, , 4/9/2004, 5:09 PM
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and utilitarian functions. Wilderness is being, preserved today in PAs because it is scenic and, serves the purpose of tourism for nature lovers,, and has recreational and economic value. Other, environmentalists stress that the goal is for protecting the useful ecological functions of the, wilderness, its services and goods that we use., Deep Ecologists on the other hand stress that, wilderness preservation is a means to achieve, the conservation and protection of biological, diversity. Thus it is not enough to protect bits of, what is left of the wilderness but to make attempts to restore degraded areas to their former, natural ecological state. In a country such as India, with its enormous population coupled with, poverty on the one hand and the need for economic industrial growth on the other, this will, be extremely difficult to achieve., , Another new approach is that of ‘Gaia’, the, hypothesis that the Earth is itself like one, giant form of throbbing life consisting of all, the unquantifiable numbers of individuals of, its millions of known and unknown species., , 7.5.3 Valuing cultures, Every culture has a right to exist. Tribal people, are frequently most closely linked with Nature, and we have no right to foist on them our own, modern way of life. The dilemma is how to provide them with modern health care and education that gives them an opportunity to achieve, a better economic status without disrupting their, culture and way of life. This will happen only if, we value their culture and respect their way of, life., , 7.5.4 Social justice, As the divide widens between those people who, have access to resources and wealth, and those, , who live near or below the poverty line, it is the, duty of those who are better off to protect the, rights of the poor who do not have the means, to fight for their rights. If this is not respected, the poor will eventually rebel, anarchy and terrorism will spread and the people who are impoverished will eventually form a desperate, seething revolution to better their own lot. The, developing world would face a crisis earlier than, the developed countries unless the rights of poor, people that are fundamental to life are protected., Modern civilization is a homogenous culture,, based until recently on a belief that modern science holds the answer to everything. We are, now beginning to appreciate that many ancient, and even present day sequestrated cultures have, a wisdom and knowledge of their own environments that is based on a deep sense of respect, for nature. Tribal cultures have over many generations used indigenous medicines which are, proving to be effective against diseases. They, have produced unique art forms such as painting, sculpture, and crafts that are beautiful and, can enrich living experiences for everyone. They, have their own poetry, songs, dance and drama, -all art forms that are unfortunately being rapidly lost as we introduce a different set of modern values to them through television and other, mass media. The world will be culturally impoverished if we allow these indigenous people to, loose their traditional knowledge which includes, sustainable use of water, land and resources, with a low impact on biodiversity. They will soon, lose the beauty within their homes that is based, on the things they make from Nature. The art, of the potter will be lost forever to the indestructible plastic pot. The bamboo basket weaver, who makes a thing of beauty that is so user, friendly and aesthetically appealing, will give, place to yet another plastic box. Much that is, beautiful and hand-crafted will disappear if we, do not value these diverse aspects of human, cultures., , Human Population and the Environment, , Chapter7.p65, , 241, , 241, , 4/9/2004, 5:09 PM
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7.5.5 Human heritage, The earth itself is a heritage left to us by our, ancestors for not only our own use but for the, generations to come. There is much that is beautiful on our Earth - the undisturbed wilderness,, a traditional rural landscape, the architecture of, a traditional village or town, and the value of a, historical monument or place of worship. These, are all part of human heritage., Heritage preservation is now a growing environmental concern because much of this heritage has been undervalued during the last, several decades and is vanishing at an astonishing pace. While we admire and value the Ajanta, and Ellora Caves, the temples of the 10th to, 15th centuries that led to different and diverse, styles of architecture and sculpture, the Moghul, styles that led to structures such as the Taj, Mahal, or the unique environmentally-friendly, Colonial buildings, we have done little to actively preserve them. As environmentally conscious individuals we need to lobby for the, protection of the wilderness and our glorious, architectural heritage., , 7.5.6 Equitable use of resources, An unfair distribution of wealth and resources,, based on a world that is essentially only for the, rich, will bring about a disaster of unprecedented, proportions. Equitable use of resources is now, seen as an essential aspect of human well being and must become a shared point of view, among all socially and environmentally conscious, individuals. This includes an appreciation of the, fact that economically advanced countries and, the rich in even poor nations consume resources, at much greater levels than the much larger, poorer sectors of humanity in the developing, world. In spite of the great number of people in, the more populous developing countries, the, smaller number of people in developed countries use more resources and energy than those, , 7.5.7 Common Property Resources, Our environment has a major component that, does not belong to individuals. There are several commonly owned resources that all of us, use as a community. The water that nature recycles, the air that we all breathe, the forests, and grasslands which maintain our climate and, soil, are all common property resources. When, Government took over the control of community forests in British times, the local people who, until then had controlled their use through a, set of norms that were based on equitable use,, began to overexploit resources on which they, now had no personal stake. Bringing back such, traditional management systems is extremely, difficult. However, in the recent past managing, local forests through village level forest protection committees has shown that if people know, that they can benefit from the forests, they will, begin to protect them. This essentially means, sharing the power to control forests between, the Forest Department and local people., , 7.5.8 Ecological degradation, In many situations valuable ecological assets are, turned into serious environmental problems. This, is because we as a society do not strongly resist, Environmental Studies for Undergraduate Courses, , 242, , Chapter7.p65, , in the developing world. This is equally true of, the small number of rich people in poor countries whose per capita use of energy and resources, and the generation of waste based on, the one time use of disposable products, leads, to great pressures on the environment. The poor, while polluting the environment have no way, to prevent it. The rich damage the environment, through a carelessness that proves only that they, have no appreciation for environmental safety., As we begin to appreciate that we need more, sustainable lifestyles we also begin to realize that, this cannot be brought about without a more, equitable use of resources., , 242, , 4/9/2004, 5:09 PM
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forces that bring about ecological degradation., These consist of sectors of society that use a, ‘get-rich-quick’ approach to development. While, ecological degradation has frequently been, blamed on the needs of fuelwood and fodder, of growing numbers of rural people, the rich,, urbanized, industrial sector is responsible for, greater ecological damage. Changes in landuse, from natural ecosystems to more intensive utilization such as turning forests into monoculture, forestry plantations, or tea and coffee estates,, or marginal lands into intensive agricultural patterns such as sugarcane fields or changes into, urban or industrial land carry an ecological price., Wetlands, for example, provide usable resources, and a variety of services not easily valued in economic terms, and when destroyed to provide, additional farmland, in many cases produce, lower returns. A natural forest provides valuable non-wood forest products whose economic, returns far outweigh that provided by felling the, forest for timber. These values must form a part, of a new conservation ethic. We cannot permit, unsustainable development to run onwards at, a pace in which our lives will be overtaken by a, development strategy that must eventually fail, as Earth’s resources are consumed and ecosystems rendered irreparable., , 7.6 HIV/AIDS, The Human Immunodeficiency Virus (HIV) causes, Acquired Immunodeficiency Syndrome (AIDS), through contact with tissue fluids of infected, individuals, especially through sexual contact. As, it reduces an individual’s resistance to disease,, it causes infected individuals to suffer from a, large number of environment related diseases, and reduces the ability of infected individuals to, go about their normal lives. It affects their income generation and/or their ability to utilise, natural resources. As more and more people are, affected, this disease will also have impacts on, our natural resource base, as utilisation patterns, change to unsustainable levels. The inability of, , these patients to have the strength to access, natural resources also affects the outcome of, the disease process, as their overall health and, well being is likely to worsen the course of the, disease when their nutritional status suffers., In sub Saharan Africa where the infection has, become highly prevalent, it is leading to great, suffering and worsening poverty. The capacity, of these patients to work for their usual sources, of income generation is lost. An increasing proportion of the poor are affected. It is evident, that it is going to be increasingly difficult to, manage environments sustainably, as natural resources on which the poor debilitated patients, depend continue to be degraded. Incomes lost, due to the stigma of HIV/AIDS must be met by, the sufferers by overexploiting their resource, base. People affected by the disease inevitably, try to get whatever they can from their natural, resource base as they are not in any position to, think of the long-term future. In Africa, this has, led to degradation of the ecosystem and an increase of pressures from other impacts such as, overuse of medicinal plants and poaching for, wildlife. In South Africa, for example, people, have a mistaken belief that turtle eggs can cure, HIV/ AIDS, thus leading to the eggs being over, harvested. As males die of the disease, work on, agricultural land has to be taken over by already, overworked women and their children, affecting land management and productivity. Providing balanced diets and nutritional support for, these poverty stricken patients can be partially, addressed by better natural resource management such as afforestation, access to clean water and wholesome food., HIV/AIDS seriously affects the patient’s working environment. It creates an incorrect fear in, the minds of co-workers. It must be clearly understood that AIDS is not spread by casual contact during work. Patients have a right to, continue to work as before along with unaffected individuals. As patients are unable to, continue their original hard labour related work,, , Human Population and the Environment, , Chapter7.p65, , 243, , 243, , 4/9/2004, 5:09 PM
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it is essential that alternative sources of work, must be created for them., Educators and extention information, in the formal and non-formal educational sectors, must, address the issues related to the linkages between natural resource management and this, disease, as well as the need to remove the social stigma attached to it., HIV/ AIDS has a serious impact on the socioeconomic fabric of society. By 2002, India had, an estimated 3.97 million infected individuals., There is a great need to organise AIDS education on prevention and management of the disease. This needs to be done through the formal, educational sector and by using non-formal, methods. Education is also important to reduce, the stigma and discrimination against these patients. In India, women who are not socially empowered are at a great disadvantage as they, are powerless to demand safe sex from their, partners. Women also have an added burden, of caring for HIV infected husbands. This produces enormous economic stresses on their family. HIV in India is rapidly moving from a primarily, urban sector disease to rural communities., , 7.7 WOMAN AND CHILD WELFARE, , Research in Nepal has shown a linkage between, rural poverty, deforestation and a shift of population to urban areas resulting in a rising number of AIDS patients. Prior to 1992, it was mainly, seen in males who migrated to urban centers., In more recent times, a growing number of, women are moving to Indian cities as sex workers. Women engaged in prostitution find it difficult to make partners take protective measures,, such as the use of condoms that provide safe, sex. A large proportion became victims of the, disease., , The diagnosis of common childhood disease, conditions, , Blood transfusion from an infected person can, also lead to HIV/AIDS in the recipient, as well as, drug abuse by sharing needles with an infected, person. In sexually transmitted AIDS, the use of, condoms during intercourse is a key to prevent-, , There are several environmental factors that are, closely linked to the welfare of women and children. Each year, close to eleven million children, worldwide are estimated to have died from the, effects of disease and inadequate nutrition. Most, of these deaths are in the developing world. In, some countries, more than one in five children, die before they are 5 years old. Seven out of 10, of childhood deaths in developing countries can, be attributed to five main causes, or a combination of them. These are pneumonia, diarrhoea, measles, malaria and malnutrition., Around the world, three out of every four children suffer from at least one of these conditions., , Presenting complaint, , Possible cause or, associated condition, , Cough and/or, fast breathing, , Pneumonia, Severe anaemia, P. falciparum malaria, , Lethargy or, unconsciousness, , Cerebral malaria, Meningitis, Severe dehydration, Very severe pneumonia, , Measles rash, , Pneumonia, Diarrhoea, Ear infection, , “Very sick” young infant, , Pneumonia, Meningitis, Sepsis, , Environmental Studies for Undergraduate Courses, , 244, , Chapter7.p65, , ing the disease. Behavioural change, where the, number of individuals who have multiple partners, towards strictly single partners, reduces the, risk of HIV/AIDS and thus reduces incidence of, the disease in society. However, the most important measure to prevent AIDS is the proper, use of condoms that form a barrier to the spread, of the virus during intercourse., , 244, , 4/9/2004, 5:09 PM
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Respiratory conditions: Most respiratory diseases are caused by or are worsened by polluted air. Crowded ill-ventilated homes and living, in smokey households with open fires can trigger respiratory conditions especially in children., , CASE STUDY, Chula issue, The World Health Organisation estimates, that 1.6 billion early deaths occur annually, from cooking stove pollution. 400,000 to, 550,000 children under five and women die, each year in India due to indoor smoke., Chula smoke is the third highest cause of, disease and death after dirty water and lack, of sanitation. Hence by providing access to, clean water, sanitation, food and ventilated, homes, over half the diseases and premature deaths could be avoided in India., , Pneumonia: Acute respiratory infections (ARI),, most frequently pneumonia, is a major cause of, death in children under five, killing over two, million children annually. Upto 40% of children, seen in health centers suffer from respiratory, conditions and many deaths attributed to other, causes are, in fact, “hidden” ARI deaths. Children may die very quickly from the infection and, thus need treatment urgently. Most patients of, pneumonia can be treated with oral antibiotics., Correct management could save over 1 million, lives per year globally., Gastro intestinal conditions: Contaminated, water and food causes widespread ill health, especially in children., Diarrhoea: Diarrhoea is caused by a wide variety of infections. Urgent diagnosis and treatment of diarrhoea is a priority for saving a child’s, life. Treating malnutrition that often accompanies diarrhoea can further reduce mortality. In-, , creasing vigilance to detect other diseases that, can occur concurrently with diarrhoea, such as, measles or malaria, is an important measure., Two million children die each year in developing countries from diarrhoeal diseases, the second most serious killer of children under five, worldwide. In most cases diarrhoea is preventable and children can be saved by early treatment. Correct management of diarrhoea could, save the lives of up to 90% of children who, currently die by promoting rapid and effective, treatment through standardised management,, including antibiotics and simple measures such, as oral rehydration using clean boiled water with, salt and sugar. In severe cases intravenous fluids must be started. Improved hygiene and management of the home and surroundings is the, most important preventative measure, as well, as improved nutrition. Increased breastfeeding, and measles vaccination have also been observed to have reduced the number of cases of, diarrhoea., Measles: Measles is a rash that appears with, fever and bodyache in children and is caused by, a virus. It infects over 40 million children and, kills over 800,000 children under the age of five., Prevention includes wider immunization coverage, rapid referral of serious cases, prompt recognition of conditions that occur in association, with measles, and improved nutrition, including breastfeeding, and vitamin A supplementation. Measles is prevented by a vaccine. Young, children with measles often develop other diseases such as acute respiratory infections, diarrhoea and malnutrition that are all linked to poor, environmental conditions in their surroundings., Children who survive an attack of measles are, more vulnerable to other dangerous infections, for several months. Effective prevention and, treatment could save 700,000 lives per year., Malaria: This condition is closely linked to pooling and stagnation of water in tropical environments. Malaria is a widespread tropical disease, , Human Population and the Environment, , Chapter7.p65, , 245, , 245, , 4/9/2004, 5:09 PM
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which is caused by a parasite transmitted to, humans by mosquitoes. It has proved difficult, to control because mosquitoes have become, resistant to insecticides used against them and, because the parasite has developed resistance, in some areas to the cheap and effective drugs, that used to provide good protection in the past., However, alternative newer drug therapies have, been developed for use in areas where resistant parasites are found. In India the disease was, nearly wiped out a few decades ago but has, now re-emerged in many parts of the country., Correct management could save 500,000 lives, per year. Approximately 700,000 children die, of malaria globally each year, most of them in, sub-Saharan Africa. Young children are particularly vulnerable because they have not developed the partial immunity that results from, surviving repeated infections., Deaths from malaria can be reduced by several, measures, including encouraging parents to seek, prompt care, accurate assessment of the condition of the child, prompt treatment with appropriate anti-malarial drugs, recognition and, treatment of other co-existing conditions, such, as malnutrition and anaemia, and prevention by, using mosquito-proof bednets. Because fever, may be the only sign of malaria, it can be difficult to distinguish it from other potentially lifethreatening conditions., Poverty-environment-malnutrition: There is, a close association between poverty, a degraded, environment, and malnutrition. This is further, aggravated by a lack of awareness on how children become malnourished., Malnutrition: Although malnutrition is rarely, listed as the direct cause of death, it contributes to about half of all childhood deaths. Lack, of access to food, poor feeding practices and, infection, or a combination of the two, are major factors in mortality., , Promoting breastfeeding, improving feeding, practices, and providing micronutrient supplements routinely for children who need them are, measures that reduce mortality., The nutritional status and feeding practices of, every child under two years of age, and those, with a low weight for their age must be intensively managed. Counseling of parents on the, correct foods for each age group and helping, them to overcome various feeding problems is, an essential health care measure., Children between 6 months and 2 years of age, are at increased risk of malnutrition when there, is a transition between breastfeeding and sharing fully in the family diet. Changing family habits and the kinds of food offered to children is, an important measure. Talking to mothers individually about home care and their child’s feeding, with relatively simple changes to better, feeding practices, such as helping them to eat, rather than leaving them to fend for themselves,, can ensure that a child gets enough to eat., A minor increase in breastfeeding could prevent, up to 10% of all deaths of children under five:, When mothers breastfeed exclusively during at, least the first four months and, if possible, six, months of life, there is a decrease in episodes, of diarrhoea and, to a lesser extent, respiratory, infections. Even small amounts of water-based, drinks decreases breastmilk intake and lead to, lowered weight gain. This increases the risk of, diarrhoea. Continuing to breastfeed up to two, years of age, in addition to giving complemenEnvironmental Studies for Undergraduate Courses, , 246, , Chapter7.p65, , Infection, particularly frequent or persistent diarrhoea, pneumonia, measles and malaria, undermines nutritional status. Poor feeding, practices - inadequate breastfeeding, providing, the wrong foods, giving food in insufficient, quantities, contribute to malnutrition. Malnourished children are more vulnerable to disease., , 246, , 4/9/2004, 5:09 PM
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tary foods, maintains good nutritional status and, helps prevent diarrhoea., Encouraging maximum support to mothers to, establish optimal breastfeeding from birth,, equipping health workers with counseling skills,, and providing individual counseling and support, for breastfeeding mothers are measures that, reduce malnutrition. Mothers often give their, babies other food and fluids before six months, because they doubt their breastmilk supply is, adequate. A one-on-one counseling with mothers on breastfeeding techniques and its benefits, helps reduce incidence of malnutrition., , There are strong connections between the status of the environment and the welfare of, women and children in India. Women, especially, in lower income group families, both in the rural and urban sector, work longer hours than, men. Their work pattern differs and is more, prone to health hazards. The daily collection of, water, fuelwood and fodder is an arduous task, for rural women. In urban areas, where lower, economic group women live in crowded smoke, filled shantys in unhygenic slums, they spend, long hours indoors, which is a cause of respiratory diseases. In urban centers, a number of, women eke out a living by garbage picking. They, separate plastics, metal and other recyclable, material from the waste produced by the more, affluent groups of society. During this process,, they can get several infections. Thus they are, providing an environmental service of great, value, but earn a pittance from this work., Women are often the last to get enough nutrition as their role in traditional society is to cook, the family meal and feed their husband and, children. This leads to malnutrition and anemia, due to inadequate nutrition., The sorry plight of women includes the fact that, the girl child is given less attention and educational facilities as compared to boys in India. Thus, , they are unable to compete with men in later, life. This social-environmental divide is a major, concern that needs to be corrected throughout, the country., , 7.8 ROLE OF INFORMATION TECHNOLOGY, IN ENVIRONMENT AND HUMAN HEALTH, The understanding of environmental concerns, and issues related to human health has exploded, during the last few years due to the sudden, growth of Information Technology. The computer age has turned the world around due to, the incredible rapidity with which IT spreads, knowledge. IT can do several tasks extremely, rapidly, accurately and spread the information, through the world’s networks of millions of computer systems. A few examples of the use of, computer technology that aid environmental, studies include software such as using Geographical Information Systems (GIS). GIS is a tool, to map landuse patterns and document change, by studying digitized toposheets and/or satellite imagery. Once this is done, an expert can, ask a variety of questions which the software, can answer by producing maps which helps in, landuse planning., , CASE STUDY, Karnataka’s GIS scheme, Bhoomi, has revolutionized the way farmers access their land, records. Farmers can now get a copy of the, records of rights, tenancy and crops from a, computerized information kiosk without harassment and bribes. Karnataka has computerized 20 million records of land ownership, of 6.7 million farmers in the State., , The Internet with its thousands of websites has, made it extremely simple to get the appropriate, environmental information for any study or en-, , Human Population and the Environment, , Chapter7.p65, , 247, , 247, , 4/9/2004, 5:09 PM
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vironmental management planning. This not, only assists scientists and students but is a powerful tool to help increase public awareness, about environmental issues., Specialised software can analyse data for epidemiological studies, population dynamics and, a variety of key environmental concerns., The relationship between the environment and, health has been established due to the growing, utilisation of computer technology. This looks, at infection rates, morbidity or mortality and the, etiology (causative factors) of a disease. As, knowledge expands, computers will become, increasingly efficient. They will be faster, have, greater memories and even perhaps begin to, think for themselves., , Environmental Studies for Undergraduate Courses, , 248, , Chapter7.p65, , 248, , 4/9/2004, 5:09 PM
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UNIT 8:, , Field Work, , Chapter8.p65, , 8.1 VISIT TO A LOCAL AREA TO DOCUMENT ENVIRONMENTAL ASSETS,, RIVER/FOREST/GRASSLANDS/HILL/MOUNTAIN, , 250, , 8.2 VISIT TO A LOCAL POLLUTED SITE, , 262, , 8.3 STUDY OF COMMON PLANTS, INSECTS, BIRDS, , 268, , 8.4 STUDY OF SIMPLE ECOSYSTEMS, , 270, , Field Work, , 249, , 249, , 4/9/2004, 5:10 PM
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8.1 VISIT TO A LOCAL AREA TO DOCUMENT ENVIRONMENTAL ASSETS RIVER/FOREST/GRASSLANDS/ HILL/MOUNTAIN, Background, Documenting the nature of an ecosystem gives us a deeper appreciation of its value to, mankind. Each ecosystem has something different to offer us. It may contain natural resources that local people depend on; or provide important ecological functions for us all; or, have tourist or recreational potential; or simply have a strong aesthetic appeal that is difficult to quantify in economic terms. In fact it can have multiple benefits for mankind at, global, national and local levels. An ecosystem is not only used by different cultures and, socio-economic groups in various ways, but has a different significance for different individuals depending on their way of life. A tribal from a wilderness setting, an agriculturalist, from farmlands, a pastoralist from grasslands, or a fisherman looks on his or her environment very differently from an urban resident who is mainly focused on the management of, the quality of air and water and the disposal of garbage. In many cultures, men and women, will have different views and relationships with Nature. In rural India, for example, it is, mostly women who collect resources and see the degradation of their ecosystem as a, serious threat to the existence of their family and are thus more prone to fight against, processes that lead to loss of their resource base., Tribal people who live by hunting and gathering have a deep understanding of nature and, what it provides for them to survive. Farmers know about utilisation of their land and, water resources, and also appreciate what droughts and floods can do to their lives. A, shepherd or livestock owner knows the grasslands intimately. In contrast, urban dwellers, are far removed from the sites from where they get their natural resources. As these have, originated from a remote area and have been collected by rural people, they cannot relate, so easily to the value of protecting the ecosystems from which the resources have come., In assessing an ecosystem’s values it is not enough to look at its structure and functions,, but at who uses it and how the resources reach the users. One also needs to appreciate, what it means to oneself. The wilderness provides a sense of wonderment for all of us, if, we experience it in person. This helps to bring about a desire to conserve natural resources., , Guidelines for the study of environmental assets:, There are two parts to this study:, 1. Documenting what you see., 2. Documenting the findings of what you ask local user groups., , Environmental Studies for Undergraduate Courses, , 250, , Chapter8.p65, , 250, , 4/9/2004, 5:10 PM
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There are several key questions that one should attempt to answer in a study of any, ecosystem’s natural resources., 1., 2., 3., 4., , What are the ecosystem’s natural resource assets?, Who uses these and how?, Is the ecosystem degraded? If so how?, How can it be conserved?, , One could go into enormous detail in answering these four basic questions. You will need, to refer to relevant chapters in this textbook, the guidelines provided in this Unit, as well as, field guides to plants, insects, birds, etc., You should begin your field study by observing the abiotic and biotic aspects of the ecosystem and documenting what you see. Ask questions to local user groups about their environment. Is their utilisation sustainable or unsustainable? Look for and document signs of, degradation. Finally, study aspects that can lead to its conservation., •, , Describe the ecosystem as you see it. Its structural nature, its quality and the differences one can perceive in its geographical features, and its plant and animal life. This, takes time and patience. The more time one spends on a careful scrutiny, the more, one begins to appreciate its intricacies., , •, , How does the ecosystem function? What are the linkages between different species, with each other and with their habitat? Observe its food chains. Look at it as if it is an, intricate machine at work., , •, , By interacting with local residents and multiple user groups, decide if this is sustainable, or unsustainable utilization. If it is undisturbed, why has it remained so? If it is sustainably, used, how is its use controlled? If it is degraded, how did it get to this state and when?, If it is seriously degraded what measures would you suggest to restore it and to what, extent could it be used so that utilisation would be sustainable?, , You may not be able to observe all these questions during a single visit. You will thus have, to ask questions of local people who have a stake in the area to answer these questions., You may need the help of an ecologist, botanist, zoologist, geologist, hydrologist or forester to get deeper insights. A historical background frequently helps to clarify many of, these questions as landscapes are not static and always change over time., , Field Work, , Chapter8.p65, , 251, , 251, , 4/9/2004, 5:10 PM
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Proforma for field work on documenting Environmental Assets of each, ecosystem, Use the format below as a general guideline for your field analysis. The points, provided in the guidelines can be used to fill in the answers to the various issues, for each ecosystem., The field work should be recorded in your Journal as:, Aims and objectives: To identify and document:, - What are the ecosystems goods and services? (checklist of resources), - Who uses them and how?, - Is the utilisation sustainable or unsustainable? (signs of degradation), - How can the ecosystem be used sustainably?, , Methodology: - Observation of the ecosystem, - Questioning local people on the use of resources and sustainability., , Discussion: Observations on levels of resource use found during the field work., , Findings: Specific concerns relevant to the study site’s sustainable utilisation as, discussed with local people., , Results and Conclusions, , Environmental Studies for Undergraduate Courses, , 252, , Chapter8.p65, , 252, , 4/9/2004, 5:10 PM
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Documenting Environmental Assets of each ecosystem, Documenting general features during the field survey: Describe the site and its features as provided in the proforma for fieldwork under the following headings – Aims and, Objectives, Methodology, Observations on the site, Findings of interviews with local people,, Results and Conclusions., , Documenting the special resource features of individual ecosystems, Once the general features are documented, observations pertaining to the specific features of the ecosystem must be documented., The checklist on resource use of each ecosystem can help in creating an environmental, profile of an area and will help in your appreciation of the ecosystem’s goods and services,, which include its important assets. However, this is to be used only as a guideline and a, note needs to be prepared on each finding once you have made your observations and, asked local people relevant questions about the ecosystem’s resources in detail. Unless one, does this for several different areas, one cannot really appreciate the assets of an ecosystem in clear terms, as these are often qualitative judgements that one makes by comparing, the resources available in the study area with many others., , Field Work, , Chapter8.p65, , 253, , 253, , 4/9/2004, 5:10 PM
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RIVER ECOSYSTEM, Guidelines on what to look for on river resource use:, •, , Observe what local people use from the river, wetland or lake:, They collect drinking water and use it for other domestic needs. They catch fish and, crabs, graze their cattle and buffaloes in or near the water. They lift water from the, lake by pumps to irrigate their fields., , •, , Mapping land use in terms of its water resources:, Document the pattern of landuse around the aquatic ecosystem –river, tank or lake,, and assess the importance of the water resources in the ecosystem. Observe that all, the animals both wild and domestic must come to the water source, or have its water, brought to them., , •, , Field observations on a river front:, 1. Observe a clean stretch of river in a wilderness area. The water is clear and full of, life. In its many pools fish dart about. Tadpoles swim around and crabs crawl along, the bottom of the water., 2. In a rural area observe all the different ways in which people use the water from, the river., 3. Observe a river in an urban area, the water cannot be used for drinking as it is, dirty. Observe the water in a glass – it is coloured – can we drink it! ‘Who has, polluted it and how?’ This is a sign of unsustainable use of water., , •, , Possible Observations:, 1. Along a river in a forest observe all the different animal tracks at the edge of the, water. All wildlife depends on this resource for their day-to-day survival., 2. Identify the different fish that local fishermen have caught. Ask if the fish catch, has decreased, remained the same, or has increased during the last decade or, two., 3. Resource use: Observe and document the different types of fish and other resources used by local people. Is this for consumptive or productive purposes., 4. Observe how the ecosystem is utilized and document these assets – water distribution, fish, crustacea, reeds, plants used as food, any other resources., , •, , In your report, compare and contrast an unpolluted and polluted body of water. Only, the more robust species remain in polluted water while the more sensitive disappear., , Water – the greatest of all resources:, What do you use water for during the course of one day?, How much do you use?, Can you stop wasting water by using it carefully?, How can you reduce the water you use for bathing and other uses?, Discuss how wastewater can be used in the garden., How can water be recycled?, Environmental Studies for Undergraduate Courses, , 254, , Chapter8.p65, , 254, , 4/9/2004, 5:10 PM
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Observations on the site that should be recorded:, •, , Type – Permanent flow/ seasonal flow. Slow moving/ rapid flow; deep/shallow., , •, , Qualitative aspects – Describe its abiotic and biotic aspects., – Is the flow natural or disturbed by a dam upstream?, , •, , Describe its aquatic plant and animal life., , •, , What are the characteristic features of its components – banks, shallow areas, deep, areas, midstream areas, islands. How is the land used?, , Findings on the site that should be recorded through interviews:, •, , What is the water used for and in what proportion? – Domestic use/Agriculture/Industry., , •, , What other resources are used – fish, crustacea, reeds, sand, etc. What impact does, the level of use have on the ecosystem?, , •, , Is the water potable? If not what are the sources of pollution – domestic sewage/, agricultural runoff/industrial effluents. Which of these affect it most seriously?, , •, , Extent of pollution – Severe/high/moderate/low/nil. Explain why., , •, , Test the water quality. What are the results of your water quality tests?, , •, , What efforts are made to keep the river clean, or to clean it up?, , •, , Is its utilisation sustainable or unsustainable?, , •, , Provide a historical profile of and changes in its environmental status by asking local, people., , •, , Does it flood? If so how frequently? How does this affect people? What preventive, steps can be taken to prevent ill effects of floods?, , •, , How can you enhance public awareness on the need for keeping the river clean?, , •, , How are you dependent on the river ecosystem? How is it linked to your own life?, , •, , Results of the water analysis., , Field Work, , Chapter8.p65, , 255, , 255, , 4/9/2004, 5:10 PM
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FOREST, Guidelines on what to look for on forest resource use:, •, , Assessing forest use:, Ask local people, especially the women, what products they collect from the forest., Document what they use for household use, those that are sold in the local marketplace and those that are taken out and sold to other areas. Fruits, leaves, roots, nuts,, fuelwood, timber, grass, honey, fiber, cane, gum, resins, medicinal products are all, forest products of great value., , •, , Looking for signs of forest use:, Several signs tell us how the forest is used by people., Look for human footprints and hoof marks of domestic animals, which demonstrates, the dependence of man and his animals on forest vegetation., Observe the number of cattle tracks and cow dung piles, which tell where the local, people graze their domestic animals. Specially look for cattle tracks near watering, places. The zigzag paths on a hillslope that have very little vegetation cover are a sign, of overgrazing., People cut the branches of the trees and shrubs for fuel wood. The amount of cut, stumps of branches can be used to assess the level of utilisation. If the forest is seriously lopped all around, the forest clearly appears degraded. Most of the energy required to cook meals and heat their homes in winter is forest dependent. Ask local, women how far they must travel for fuelwood. Larger stumps of tree trunks show the, number of poles used for building houses, or that have been felled and sold as timber., Observe the environment in a neighbouring village. Look for the various products used, by the people, or marketed by them, which they get from the forest., Where do local people get their water? The presence of water in the streams is dependant on the existence of the forest., , •, , Document the level of forest loss:, Observe areas around villages where forest is overused and contrast this to the intact, vegetation of Sanctuaries and National Parks. Are there signs of degradation of the, canopy, formation of wasteland or signs of soil erosion?, , •, , What are the products that you use in daily life that originate in forests?, Examples: water, paper, wood, medicines. The oxygen we breathe is produced by, vegetation etc. Draw up a list of articles you use that could have originated from a, forest ecosystem., , Observations on the site that should be recorded:, •, , Identify the forest type – evergreen/ semi evergreen/ deciduous/ dry deciduous/ thorn, forest., Environmental Studies for Undergraduate Courses, , 256, , Chapter8.p65, , 256, , 4/9/2004, 5:10 PM
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•, , Is it a natural forest or a plantation?, , •, , Observe its qualitative aspects – Undisturbed/ partially disturbed/ mildly degraded/ severely degraded., , Findings on the site that should be recorded through interviews:, •, , List its natural resources – goods and services., Goods- food, fuelwood, fodder, non-wood forest products, water, etc., Services- water regime, climate control, oxygen, removal of carbon dioxide, nitrogen, cycle, etc., , •, , Who uses the ecosystem’s natural resources and to what extent? List the level of use, of each of its natural resources (sustainable/ unsustainable). Are these used for personal use, for marketing or for both? What proportion of the income of local people, comes from the sale of fruit, fodder, wood, non-wood forest products?, , •, , Make a map of the study area showing the different land uses and where resources, are collected from., , •, , Provide a historical profile of its utilisation and changes in its environmental status by, asking local people about their resource dependency., , •, , Is the ecosystem overused due to the number of people that depend on it, or the, greed of a few, or both?, , •, , Is it protected, if so how?, , •, , If it is to be restored, how can one make this possible?, , •, , What forest produce do you use in your day to day life?, , Field Work, , Chapter8.p65, , 257, , 257, , 4/9/2004, 5:10 PM
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GRASSLAND, Guidelines on what to look for on grassland resource use:, •, , Utilisation pattern of the grassland:, Discuss with local people how they use the grasslands, grazing cattle, cutting fodder,, collecting fuelwood from the shrub cover etc., , •, , Grassland carrying capacity:, Observe the enormous quantity of grass needed for the number of domestic herbivores dependent on it. This is an indication of the ‘carrying capacity’ of the grassland,, ie how many animals it can support., , •, , Mapping landuse in grassland areas:, Near a village make a landuse map showing where the cattle are sent for grazing and, for water, where people collect fuelwood, etc., , •, , Documenting grassland degradation:, Document if there has been a change in landuse patterns during the last few decades, by asking local people. Observe differences in protected and degraded areas., , •, , What are the products that you use that come from grasslands?, Examples: milk, meat, etc., , Observations on the site that should be recorded:, •, , Identify the type of grassland – Himalayan/ Terai/ semi-arid/ shola/ area developed for, grass collection/ common grazing land/ forest clearing., , •, , Qualitative aspects – Describe its abiotic and biotic features – Document the nature of, its soil, plant and animal species (wild and domestic). How do they use their habitat?, , •, , What changes occur seasonally?, , Findings on the site that should be recorded through interviews:, •, , Who uses it and to what extent?, , •, , Estimate the extent of free grazing – cattle, sheep, goats, and their proportion., , •, , Extent of fodder collection., , Environmental Studies for Undergraduate Courses, , 258, , Chapter8.p65, , 258, , 4/9/2004, 5:10 PM
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•, , What is the productivity of the grassland? Estimate from local people if the fodder is Not enough for their own livestock/ just enough for their own livestock/ enough for, their own livestock and to sell to other fodder short areas., , •, , Provide a historical profile of its utilisation and changes in its environmental status by, asking local people., , •, , Is this utilisation level sustainable or unsustainable?, , •, , Is the grassland burned too frequently? Document why local people burn the grass., , •, , Can they do a rotation grazing of their common grasslands and thus manage it better?, , •, , What products do you use from grassland ecosystems in your daily life?, , Field Work, , Chapter8.p65, , 259, , 259, , 4/9/2004, 5:10 PM
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HILLSLOPE, Guidelines on what to look for on hill resource use:, Hills are fragile ecosystems that are easily degraded. They are however utilised by a variety, of user groups. Understanding the level of pressure can be observed and its utilisation, patters elicited from local people., , Observations on the site that should be recorded:, •, , Identify the type of hill – steep/ gradual slope. Top – peak/ plateau top., , •, , Qualitative aspects – Describe its abiotic (soil characteristics) and biotic (vegetation), characteristics., , •, , Describe its contour and make a map marking its features such as nala courses, rocky, outcrops, precipices, springs., , •, , Describe if its soil cover is intact/ degraded/ partially or severely eroded., , •, , Is it covered with cattle tracks? Do hoof marks of domestic animals and their dung, piles indicate excessive grazing?, , •, , Describe its vegetation profile and map different vegetation patterns (tree cover, scrub,, grass cover, bare rock)., , •, , Identify the plants that grow on it (trees, shrubs, herbs, grasses) and wild and domestic, animals present., , Findings on the site that should be recorded through interviews:, •, , What is it used for – Urban housing/ slum development/ tourism/ fuelwood collection/, grazing livestock/ collecting water from its watercourses/ greening. Observe the proportion or extent used for each purpose. Is it sustainable?, , •, , Provide a historical profile of its utilisation and changes in its environmental status by, asking local people., , •, , If it is eroded, what measures can be suggested to reverse the trend?, , •, , How is this linked to your own life?, , Environmental Studies for Undergraduate Courses, , 260, , Chapter8.p65, , 260, , 4/9/2004, 5:10 PM
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MOUNTAIN, Guidelines on what to look for on mountain resource use:, Mountains have very specialized ecosystems with clearly defined altitudinal variations. They, are used by several different stake holders. Effects of human interference on mountains, affect people in the valleys below., , Observations on the site that should be recorded:, •, , Identify the type – Himalayan range/ foothills., , •, , Qualitative aspects – Describe its abiotic and biotic features., , •, , Describe its topography and soil characteristics. Make a map marking its features., Snowcapped/ rocky precipice/ grassy slopes/ tree line. Discuss proportion of each type., , •, , Describe its plant and animal species. How do they use their habitat?, , •, , Identify the forest type with its dominant (common) tree species., , •, , Describe its soil cover/ degree of erosion., , Findings on the site that should be recorded through interviews:, •, , Describe the utilisation pattern of any forest cover and its grassy slopes., , •, , Who uses it?, , •, , Do local people get as much natural resources from it today as they did in the past?, - If yes, how is this managed?, - If no, why not, and what measures can be taken to remedy these trends?, , •, , Provide a historical profile of its utilisation and changes in its environmental status by, asking local people. Have there been landslides or floods in the valley below?, , •, , How is our own life linked to this ecosystem?, , Field Work, , Chapter8.p65, , 261, , 261, , 4/9/2004, 5:10 PM
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8.2 VISIT TO A LOCAL POLLUTED SITE, Pollution occurs from a variety of sources and affects different aspects of our environment, and thus our lives and our health., Polluted sites include urban, rural, agricultural and industrial areas., Identify the site type and describe the sources of pollution., Pollution can affect:, • Air (smoke, gases),, • Water (urban sewage, industrial chemical effluents, agricultural pesticides and, fertilisers),, • Soil (chemicals, soild waste from industry and urban areas),, • Biodiversity: effects on plant and animal life., (Observations on pollution must include all the above aspects.), , General observations:, The following aspects need to be observed and documented:, •, , The type of land or water use in the polluted area, it’s geographical characteristics,, who uses the area, who owns it., , •, , Map the area to be studied., , •, , Identifying what is being polluted – air, water, soil; the cause(s) of pollution and the, polluting agent(s)., , •, , Assess the extent of pollution – severe/moderate/slight/nil, to:, air, water, soil, biodiversity., , •, , Assess from literature, the health aspects associated with the pollutant., , •, , Ask local residents about its effect on their lives., , •, , Make a report of the above findings., , Environmental Studies for Undergraduate Courses, , 262, , Chapter8.p65, , 262, , 4/9/2004, 5:10 PM
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Proforma for fieldwork, Aims and objectives: To study the cause and effects of pollution at the site., Methodology: Certain key questions related to the polluted site are given below., Explore the site to answer the questions about the area you have visited., •, , What is the site?, Rural - agricultural area, polluted waterbody, polluted industrial area, Urban - Solid waste management site, Polluted industrial area, , •, , What do you observe at the polluted site?, A solid waste- garbage dump, polluted water at a river or lake, gaseous effluents or smoke coming out of an industry area, etc., , •, , Explore the reasons for pollution. Observe and document the components in, the garbage/ the polluted waterbody/ industrial chimneys., , •, , Observe the area and list the waste that is seen in the garbage dumping site., Categorise the waste into the three types:, - Degradable wastes, are those which are easily decomposed by micro organisms. These include food wastes, plant material, animal carcases, etc., - Non-degradable wastes are those which are not easily decomposed. Eg., plastic, glass., - Toxic wastes are those that are poisonous and cause long term effects., Eg. Several chemicals, paints, sprays, etc., , Findings:, •, , What are the effects of the pollutant?, , •, , What actions can you take to get the pollution reduced?, , Field Work, , Chapter8.p65, , 263, , 263, , 4/9/2004, 5:10 PM
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1. SOLID WASTE study site, Guidelines for the study of solid waste polluted sites:, Pollution caused due to solid waste can be seen at various places:, A. Garbage dumps: One of the urban or rural environmental problem sites that can be, studied is a garbage-dumping area. This problem is basically due to increase in population,, an over utilization of non-biodegradable disposable consumer goods and lack of awareness of the management of waste at the household level. How much garbage is produced, everyday is not given much thought. No one really thinks about where the garbage goes or, what happens to all the things we throw away., Garbage is a source of various diseases. Improper handling of organic waste leads to a, large population of flies, cockroaches and rats that are responsible for the spread of diseases. Products like plastics are not degraded in nature and hence remain for a long time in, the environment, thus adding to the need for more dumps. For many years waste has also, been dumped into oceans, rivers or on land. These methods off disposing off waste contribute to contamination of soil, groundwater under the dumping site, foul up the air and, aid the spread of diseases., , Interview of a ragpicker at a roadside disposal area or at a dump and understand their problems., Prepare a survey sheet and ask them:, •, What is the area covered in a day?, •, How many hours are spent in collecting the waste?, •, What are the types of waste collected?, •, What are the problems faced while collecting waste?, •, What do they prefer to collect and why?, •, What is done with the waste collected?, •, If it is sold, where?, •, Would it be better to collect waste from homes rather than from roadside bins?, •, Do they feel that segregation of waste would help them?, , It is essential to understand that ragpickers do an environmentally important activity for, all of us. While we throw away our own waste insensitively, it is they who separate out, various types of waste for recycling and reuse. They are thus performing a great proenvironmental function for most of us., , Environmental Studies for Undergraduate Courses, , 264, , Chapter8.p65, , 264, , 4/9/2004, 5:10 PM
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Study of a dump site, The location of the site and where the garbage comes from., How it is collected, by whom and with what frequency., Understand how the waste is managed., What are the different types of garbage?, What proportion is non-degradable and degradable?, What can we do to reduce the quantity of garbage?, , B. Households: The garbage generated in our homes is termed domestic waste, while a, community’s waste is referred to as municipal waste. This is classified as kitchen waste,, which is degradable, wet waste and non-biodegradable recyclable home waste which consists of plastic, glass and metal. Observe and document what happens in homes of different economic groups. What happens to your own household waste? Could it be managed, better?, C. Agriculture: Agricultural waste consists of biomass including farm residues such as rice, husk, straw, bagasse, etc. This biomass could be effectively used for generating power or, producing paper. Waste material from fields includes fertilizers and pesticides that are a, serious health hazard., D. Industries: Industrial solid waste includes material from various industries or mines., Industries produce solid wastes during manufacturing processes. Some of these are chemicals that have serious environmental ill effects, as they are toxic. Visit an industry and ask, what are the waste products and how they are disposed off., The waste generated during mining is non-biodegradable, it remains in the environment, nearly indefinitely. Solid waste is also generated as a result of excavation and construction, works., E. Hospitals: The waste generated from hospitals contains cotton dressing and bandages, with blood or other tissue fluids and pus, all of which can contain pathogens. It can spread, bacteria, fungi and viruses. Used needles, syringes, bottles, plastic bags, operation theatre, waste, such as tissues, blood, plastic disposable equipment all need very careful disposal., The hospital should have a waste separation system at source into biomedical waste, glass,, plastics, etc. The biomedical waste can be autoclaved or incinerated so that microorganisms are killed., , Field Work, , Chapter8.p65, , 265, , 265, , 4/9/2004, 5:10 PM
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2. WATER POLLUTION site, Guidelines for study of polluted water sites:, Observe if the river/ lake/ tank can be considered unpolluted/ slightly polluted/ moderately, polluted or severely polluted by looking at the water and by simple tests using a water, monitoring kit., •, , Document the name of the river and the nearby urban or industrial site from where, the pollution is generated., , •, , Is there urban garbage dumped on the bank?, , •, , Are there industrial units near the site?, , •, , Do the industries discharge their wastewater into the site? Is this treated or untreated?, , •, , What is its colour and odour?, , •, , Are there any sources of water contamination from the surface runoff from adjacent, agricultural land on which fertilizers and pesticides are used?, , •, , Ask fishermen if this has affected their income., , •, , Identify plants, birds and insects found on the banks., , Environmental Studies for Undergraduate Courses, , 266, , Chapter8.p65, , 266, , 4/9/2004, 5:10 PM
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3. AIR POLLUTION site, Guidelines for the study of polluted air sites:, Air pollution sites include cities due to traffic congestion in urban centers and industrial, areas due to gaseous products released during manufacturing processes., •, , Ask people from the area the effects on their lives., , •, , How can this be reduced?, , •, , How can you make more people aware of this issue and the effects on their health?, , Field Work, , Chapter8.p65, , 267, , 267, , 4/9/2004, 5:10 PM
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8.3 STUDY OF COMMON PLANTS, INSECTS, BIRDS, Guidelines for the study:, These taxa have been selected as they occur nearly everywhere. Whereas one may have to, visit a National Park or Sanctuary to see mammals or reptiles, several plants, insects and, birds can be seen around an urban or rural setting where there is some vegetation., If you have an opportunity to visit a National Park or Sanctuary, you can add other animals., One needs a little equipment – a journal to take notes, preferably a pair of binoculars, field, guides to identify plants, insects, birds, reptiles and mammals. These are available from, Bombay Natural History Society (BNHS)., , Field reference books:, 1. The book of Indian Animals – S.H. Prater, BNHS, 2. The book of Indian Birds – Salim Ali, BNHS, 3. The book of Indian Reptiles – J.C. Daniel, BNHS, 4. Field Guide to the Common Trees of India – P.V. Bole and Y Vaghani, BNHS, 5. CD ROM on The Biodiversity of India – EK Bharucha, Mapin Publishing, , Plants:, 1. Identify and list common plant species at the study site (at least 20; 10 trees, 5 shrubs,, 5 herbs)., 2. Identify if there are rare species by using a field guide or asking a botanist., 3. Identify and list the types of plants – trees/shrubs/climbers/ground cover – herbs, grasses., Observe their abundance levels., 4. Describe five plant species. Document the characteristic features that help in identification of the selected species:, Specific characteristics of leaves/ flowers/ fruit/ seeds., Describe the plant’s role in the ecosystem., How is it used and by whom?, Is it being collected sustainably or over harvested?, Is it common or rare? If rare, why?, Is it a keystone species? If so why., , Environmental Studies for Undergraduate Courses, , 268, , Chapter8.p65, , 268, , 4/9/2004, 5:10 PM
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Animals:, •, , Identify and list all the species you see in the study site., , •, , What are the major field identification features of the common animals and birds that, you observe?, , •, , Look for and document for each group; insects, birds (mammals if possible) at least 10, species., Document the characteristic features for each of the ten species and record the following:, , •, , a), , The role of the species in the ecosystem: What role does the species play in nature, – producer, herbivore, carnivore, decomposer, pollinator, seed dispersal agent,, pest, etc., , b) The level of abundance at the site – Classify as abundant/ common/ rare/ very, rare., •, , Watch and document the area unobtrusively to observe all the linkages between the, different species and between a species and its habitat. What role does each species, play in the food chain and energy pyramid?, , •, , Observe the habits of each of the selected species such as feeding behaviour, nesting, (for birds), breeding, territorial behaviour, etc., , •, , Refer to a relevant field guide and document the following:, - The distribution of each of the selected common species in the country., - The current status from a field guide – abundant, common, uncommon, rare,, endangered. If rare, is it on the endangered list?, , •, , Is it used by people? For what purpose?, , •, , How can it be protected?, , Field Work, , Chapter8.p65, , 269, , 269, , 4/9/2004, 5:10 PM
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8.4 STUDY OF SIMPLE ECOSYSTEMS, , Field studies to be documented:, Describe any two ecosystems in the same way - specific forest type, marine, coastal,, mangrove delta, lake, cave, etc. that you have visited for documentation of an ecosystem., Discuss its abiotic and biotic aspects., Describe its common species and their habitats., Describe its food chains, food web, food pyramid., Discuss its biogeochemical cycles., Describe all its habitat characteristics., Describe its utilisation., Discuss its conservation potential., Remember to take the time also to just enjoy the feeling of being with Nature., Learn to appreciate the beauty of natural vegetation. It can become a thrill to, watch wild species of animals and birds without disturbing them in their habitat., , General guidelines on aspects that can be observed and documented during ecosystem field studies:, 1. The major questions that must be addressed during a field visit to any ecosystem such, as a forest, grassland, semi-arid, desert, hills, mountain ranges, lake, river or seacoast, include:, •, , What is the ecosystem called on the basis of its typical features? What are its, abiotic and biotic characteristics?, , •, , Are its goods and services being misused or overused? What are the signs that can, be observed of degradation of the ecosystem that have occurred in the area?, Deforestation, pollution of a waterbody, soil erosion, are signs of degraded ecosystems., , •, , How can this degradation process be prevented by sustainable use of the, ecosystem’s goods and services by changing ones own habits, such as by saving, water, electricity, paper etc?, , •, , How can we all care for our ‘mother earth’ in our own way? Many small actions, together reduce the adverse impacts of human activities on the ecosystems., , Environmental Studies for Undergraduate Courses, , 270, , Chapter8.p65, , 270, , 4/9/2004, 5:10 PM
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2. Observing the Water Cycle:, , During a monsoon field trip observe the effect of the rain., •, , The type of vegetation is an indicator of the amount of rainfall. Classify the ecosystem: forest / grassland/ semiarid/ desert type on the basis of rainfall., , •, , Observe how rain percolates into the subsoil. This recharges ground water, which, charges wells, streams and rivers., , •, , Document if the rain is eroding the soil. This can be judged by observing if the, water is brown in colour. The colour is an indicator of the extent of soil erosion, and is darker wherever plant cover has been destroyed. It takes thousands of years, for new soil to form. Excessive silt eventually changes the course of the river and, leads to flooding of surrounding land., , 3. Observing the Carbon Cycle:, , Since plants take up carbon dioxide, which we exhale, and split it into carbon and, oxygen, which we breathe, we are dependent on the plant life on earth. Eventually, large-scale deforestation could make life on earth impossible. Document this as an, ecosystem service., Carbon is a component of the food we eat in the form of carbohydrates, which come, from plant material. Thus we need plants to give us oxygen and food, without which, we cannot survive., , 4. Observing the Oxygen cycle:, , While on the field trip focus attention on the amount of green material that plants, contain. Without this there would not be enough oxygen for animals to breathe., Sunlight is essential for plant photosynthesis, which produces new leaves, branches, and the growth of the trunks of trees. It leads to growth of grass and herbs every year., Sunlight is essential for plant growth in the water, including microscopic algae and, underwater vegetation which is the food producer for all aquatic forms of animal life., , 5. Observing the Nitrogen Cycle:, , Observe the quantity of dried leaves on the ground in a forest, or the dried leaves of, plants planted in the area that have collected as detritus. This material can be seen to, be decaying. Ants, beetles and worms that feed on this dead material are breaking it, up into small fragments. Microscopic bacteria and fungi are acting on this material to, convert it into nutrients for plants to grow., , Field Work, , Chapter8.p65, , 271, , 271, , 4/9/2004, 5:10 PM
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6. Observing the Energy Cycle:, Look for the different types of insects and birds in the trees. Frugivorous birds feed on, fruit, insectivorous birds and spiders feed on insects. These form food chains. There are, thousands of such food chains in an ecosystem. These inter-linked chains can be depicted in the form of a ‘web of life’. Observe that in our surroundings there is a great, amount of plant material. There is much less animal life in which there are a relatively, larger number of herbivores than carnivores, which live on herbivorous animals. Estimate and document the differences in the number of plants, herbivores and carnivores in an area. This can be depicted as a food pyramid., , Specific ecosystem studies:, Objectives of a Field Visit to an Ecosystem:, , Identify the local landscape pattern in the forest, grassland, desert, river, hills, etc. These, are unmodified ‘natural’ ecosystems., Identify the modified ecosystems such as farmland, grazing land, industrial land and urban, land. Compare and contrast natural and intensively used areas., The study site may have a mosaic of landscapes and aquatic ecosystems. Use the observations to create a map of the area and its ecosystems., Document the following:, A. Common plants you see (trees, shrubs, grasses, etc.)., B. Animals observed (mammals, birds, fish, insects, etc.)., The natural landscape is beautiful. Describe how you feel about it. The plants and animals, have several exciting features that can be ‘discovered’. Observe and document their abundance or rarity, their habitat, their behaviour and their links to other species., , Environmental Studies for Undergraduate Courses, , 272, , Chapter8.p65, , 272, , 4/9/2004, 5:10 PM
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A. FOREST, Field Visit to a Forest – Depicting the nature of the ecosystem:, , Visit the nearest or most convenient Reserved Forest, National Park or Wildlife Sanctuary., Meet the Forest Official to explain your study. Check if there is an Interpretation Centre, where there may be local information. Ask for brochures or other material. Officials may, agree to address a group of students. Observe the forest type. Make notes on the ecosystem.., •, , Classify the forest type:, , During the field visit to the forest identify which type of forest is found in the area. Is, there only one type or are there several types? If so why?, Coniferous, deciduous, evergreen, thorn forest and mangrove are some examples., •, , Interpreting the connection between abiotic and biotic aspects of the ecosystem:, Observe differences in vegetation types during the field visit and relate this to abiotic, features such as temperature, rainfall, soil and topographic patterns wherever possible., , •, , Understanding food chains and food pyramids:, , •, , -, , Observe the abundance of different species in the ecosystem., Observe which plants are found commonly in the forest. Only a few species are, very abundant but there are a large number of less common species of trees,, shrubs and climbers and small ground plants that add to the diversity of plant life, in any forest., , -, , Observe and document the names of animals seen. Classify them as mammals,, birds, reptiles, amphibian or insects. Classify these into herbivores and carnivores., If these are counted, you will appreciate that there is a relative abundance of, herbivores over carnivores., , Identify the structural levels in a forest:, , Identify the layers of the forest. Draw profiles of the structure and label the levels., Ground – trunk – branches – canopy., •, , Document the micro-habitat for species in different levels of the forest:, , Observe which animal uses different parts of a forest habitat. Some live on the ground, among the fallen leaves (worms and insects such as ants, termites and beetles), others, live in the middle layer on branches and tree trunks (lizards and woodpeckers), many, others live in the canopy of the tree tops, (such as fruit and nectar dependant birds, such as sunbirds, parakeets and mynas. There are insectivorous birds, (flycatchers,, drongos and bee eaters) in the canopy. Several insects live under the ground. If one, turns over dead leaves on the forest floor there are a large number of animals (millipedes, ants, beetles etc.)., Field Work, , Chapter8.p65, , 273, , 273, , 4/9/2004, 5:10 PM
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Document what you have seen and estimate their abundance at different levels., •, , Observe food chains and interpret the food web., , Field Observation – examples of food chains that are easily seen:, Flower → butterflies → spiders, Flower → sunbirds → birds of prey, Fruit → parakeet → birds of prey, Seeds → rodents → birds of prey, Flowers → bees → bee eaters, Seeds → munias → small carnivorous mammals and birds of prey, Leaves → monkey → leopard, Grass → chital → tiger, , Observe what all the animals are feeding on and reconstruct as many food chains as, possible., Observe that a single species can play a role in several food chains. Thus the chains, form a food web., Write about what you have seen about the food chains and food web in the area., •, , Interpreting the food pyramid and biomass distribution:, , Observe that in the forest the number of trees, shrubs and ground cover of plants, constitutes an enormous amount of living material (biomass). Compared to this plant, life, the number and biomass of herbivores is less while the number and biomass of, carnivores is smaller still., Write an explanation for this phenomenon using the examples you have observed in, the study site., , Though ants are very small, together the thousands of ants form a large amount of, living material. Thus they have a great influence on the ecosystems functions., Observe and document how an ant colony works together., •, , Explaining the detritus cycle:, , Observe the large number of ants and beetles in the dead leaves fallen on the forest, floor. Together they constitute a very large mass of living animals. They thus breakdown an enormous amount of dead plant and animal waste material. Without this, process the forest ecosystem would loose its integrity., See what earthworms, millipedes, ants and beetles do without disturbing them. Insects and earthworms moving on the forest floor are breaking down the detritus so, that microscopic fungi and bacteria can recycle this material into nutrients for the, forest plants to grow. Look for the larger fungi such as mushrooms and bracket fungi, that also do this work. This shows how the cycle works., , Environmental Studies for Undergraduate Courses, , 274, , Chapter8.p65, , 274, , 4/9/2004, 5:10 PM
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•, , Interpret the temperature and moisture control functions of the forest:, , Observe temperature differences under a closed forest canopy and outside in the open., Feel the moisture in the detritus and superficial layers of soil, which can be compared, with the dry soil elsewhere., •, , Appreciate species diversity:, , Make a rough estimate of the number of species of the trees, shrubs and the different, plants that form the ground cover. One need not name them all. Appreciate the wide, variety of plants in a forest as compared to a mono culture plantation., •, , Appreciate abundance of different plant species:, , Look around at the trees in the forest. Only a few are very abundant, while a much, larger number of species are uncommon. Identify the most commonly observed trees., Appreciate that there are some rare species of plants. These can become extinct if the, forest is cut down., •, , Appreciate abundance of different animal species:, , On the forest floor the most commonly observed animals are ants. There are more, ants than any other animal species on earth. Look for beetles. There are more species, of beetles in the world than any other group of species. Observe how many different, types of beetles there are, even though one cannot name them., The integrity of the ecosystem is based on these small but very important species that, are a major part of the web of life of the forest. They are the prey of insectivorous, birds, amphibians and rodents., Insects break down the detritus of the forest, which is the nutrient material on which, the forest plants grow., Mankind thus cannot survive without these ants as they produce the nutrient material, on which plants depend. Man is dependent on plant life, and is thus indirectly dependent on the insects in the forest detritus., •, , How do forests influence the water cycle?, The forest acts as a sponge: Feel the moisture and coolness of the forest air and compare this with the drier and warmer temperature outside the forest cover. The difference is obvious as shade of the trees reduces the local temperature. Feel the level of, moisture on the forest floor and compare this to the dryness of the ground outside the, forest. A considerable amount of moisture is retained in the dead leaves (humus) of, the forest floor. Dig a small hole in the ground. It is moist and cool under the forest, floor. This demonstrates how the forest acts as a sponge and releases water gradually, into streams after the monsoon is over. This can continue for the rest of the year and, provide water for people outside the forest., , Field Work, , Chapter8.p65, , 275, , 275, , 4/9/2004, 5:10 PM
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•, , Understanding Prey and Predator relationships – Food chains:, , There are spiders on the ground, which form tunnel webs to catch the crawling insects. In the trees wood spiders make giant webs three feet in diameter to catch flying, insects. Look for the insect life in the canopy of the trees, on trunks, on the ground and, especially under dead fallen leaves., Identify which species are predators and what is their prey., •, , Searching for examples of food chains, food webs and food pyramids:, , Different species of lizards are found on the tree trunks and on the forest floor. There, are chameleons in the trees and skinks on the ground. They are feeding on insect life,, which in turn feed on the plants. This is a simple food chain that can be easily observed., A spider catching an insect in its web is another demonstration of a simple food chain., The same insects are used by spiders and lizards as prey. Thus multiple food chains are, linked to each other. This forms a small part of the food web of the forest., There are several insectivorous birds such as bee eaters, fly catches of many species,, babblers, etc. that form many different food chains., There has to be a very large amount of plant life to provide enough food for the, herbivores, which are prey species for the very few carnivores in the forest. This demonstrates how a food pyramid works and how energy moves from one level to the, other. The energy is used for day to day functions of animals such as hunting for food,, respiration, metabolising food and breeding. Observe that there is a very large amount, of plant life, a smaller number of herbivores and very few carnivores. This observation, explains the concept of the food pyramid., •, , Document the linkages between food chains and processes such as pollination of plants, in the forest:, , Animals such as monkeys, squirrels and birds feed on leaves, fruits and seeds. Insects, such as ants, butterflies and birds such as sunbirds and mynas use flower nectar for, food. These flowers have bright colours to attract them. During this process the insects, and birds pollinate the plants., At night when most animals sleep, the bats and moths pollinate flowers. These flowers, are usually white in colour so that they can be seen at night., Thus many plants depend on animals to pollinate them so that seeds can develop. The, regeneration of forests thus depends on these animals. These linkages are important, aspects that maintain the forest’s web of life., Look for the pollinators – butterflies, moths, beetles, ants and nectar feeding birds are, easy to observe., Look for birds that eat berries and fruit and disperse seeds. These include bulbuls,, parakeets., Look for birds of prey that complete the food chain., , Environmental Studies for Undergraduate Courses, , 276, , Chapter8.p65, , 276, , 4/9/2004, 5:10 PM
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•, , Seed Dispersal:, , Observe that monkeys, squirrels and birds such as parakeets, mynas and hornbills are, agents of seed dispersal as they feed on fruit and spread the seeds far and wide. Birds, such as bulbuls eat small berries along with their seeds. After passing through the, birds’ intestines they are defecated and can germinate. They germinate more effectively as their covering is removed in the bird’s intestine. The birds thus help in the, dispersal and regeneration of plants. Though a plant is rooted to the same spot, evolution has linked plants with animals that help the plant species to spread by dispersing, its seeds., Other seeds are light and have wings or hair. These are dispersed by the wind. Observe, how these float thought the air for long distances., •, , Regeneration:, , Look for seeds and seedlings growing on the forest floor. Observe that while there are, plenty of small seedlings there are fewer saplings as a majority of seedlings die. Only, a few of the surviving young saplings will finally grow into large trees. Plants thus need, to generate a very large number of seeds. Only those seeds that find a spot that has all, the conditions needed for their germination and growth can end up as large trees., Many seedlings die due to forest fires, grazing or trampling by domestic animals., •, , Forest Animal Communities and interrelationships:, , Forest birds form feeding parties of many different species. Together they feed on, different parts of plants such as flower nectar, fruit, or on insects. Observe that when, fruit eating birds search for their food in the foliage they disturb the hiding insects,, which are then caught by the insect-dependent birds. Others, while looking for berries, in the bush layer, disturb insects that are caught by other insectivorous birds. Thus, birds of different species help each other in finding their food and stay together in, large mixed feeding parties that move from one tree to another. Identify what each, bird species feeds on., When the langurs feed on fruit, a part of the fruit is dropped uneaten on the forest, floor. Chital and sambar deer following the langurs are able to eat this fallen fruit., From the top of the tree the monkeys can easily spot an approaching tiger or leopard, more easily than the deer. The monkey gives an alarm call at the approach of a predator alerting the deer to its approach., •, , Major prey- predator behaviour:, , Carnivorous animals are very shy of human beings, as man has killed them for thousands of years. These animals are very stealthy so that they can catch their wary prey., They become invisible as their colour and pattern camouflage them in the undergrowth to be able to approach the prey unnoticed. The predators have to make several unsuccessful attempts before they catch their prey, as the prey is extremely sensitive, to any movement or sound. For these unsuccessful attempts they have to spend a, large amount of energy to catch the watchful deer. The deer have sharp eyesight and, a good sense of smell to avoid being caught. Predators like tigers or leopards counter, this by moving very cautiously in the forest. Other predators such as wild dogs hunt in, Field Work, , Chapter8.p65, , 277, , 277, , 4/9/2004, 5:10 PM
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packs. Omnivorous birds such as hawks and eagles swoop down from the sky on their, quarry at great speed. Even though they are superb hunters, their prey is frequently, able to escape., •, , Searching for camouflaged species:, , The beautiful stripes of the tiger and the rings of the leopard match the light and, shade in the forest and thus camouflage these animals so that they cannot be easily, seen. They can sometimes be only a few paces away in the undergrowth and yet, remain completely invisible. Predators such as tigers and leopards frequently see us, before we see them and disappear stealthily into the deeper forest. However we can, observe their pug marks on the forest floor. It is exciting to see a fresh pugmark in the, forest. It tells a tale. The track if fresh can end up at a sleeping tiger or a leopard!, The colour of moths is similar to that of the brown tree bark on which they rest during, the day., Chameleons change their colour to suit their surroundings., The green colour of grasshoppers matches the foliage they live in., Stick insects look like twigs., Look for other signs of camouflaged species in the forest. Each has a reason and is, linked with evolutionary processes., •, , Study of wildlife signs:, , The wildlife of the forest leaves behind several signs even if we cannot see the animals, themselves. Each animal has its own footprint, which can be identified. Animals also, leave their characteristic droppings that can be easily identified. Thus these signs in the, forest can tell us which species live there and indicate their day to day activities., Listen to the birdcalls. There are many different kinds of beautiful calls. This indicates, that there are many more birds than we can see in the forest., •, , Observe feeding patterns of animals:, , Observe the feeding patterns of forest animals unobtrusively. Learn about those that, we cannot observe easily. Some of these are given below:, •, , Tigers feed on sambhar, chital deer and monkeys., , •, , Leopards feed on barking deer, hare, and occasionally village cattle., , •, , Jackals feed on hare, mice, and birds., , •, , The Jungle cat feeds on hare and mice., , •, , Pangolins feed on ants., , •, , Mongoose feeds on snakes and mice., , •, , Cheetal feed on grass., , •, , Sambar feed on grass, young leaves and fruit of shrubs and trees., , •, , Barking deer feed on fruit and leaf buds., Environmental Studies for Undergraduate Courses, , 278, , Chapter8.p65, , 278, , 4/9/2004, 5:10 PM
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•, , •, , Elephants feed on grass in the monsoon and tree leaves in the winter and summer., , •, , Squirrels feed on nuts and fruit., , •, , Porcupines feed on fleshy roots of plants and bark of trees., , •, , Birds of prey feed on rodents, reptiles, frogs and small birds., , •, , Birds like flycatchers feed on insects and worms., , •, , Bulbuls feed on fruit. When they have young one’s in the nest the parents feed, the chicks with worms and caterpillars., , •, , Sunbirds feed on flower nectar., , •, , Spiders catch insects., , •, , Insects like beetles and bugs feed on plant material., , •, , Insects like the praying mantis and dragonfly feed on other smaller insects., , •, , Ants and termites feed on plant material that is dead., , •, , Beetles and bugs feed on leaves and sap of plants., , •, , Butterflies feed on flower nectar in the day., , •, , Moths feed on flower nectar at night., , •, , Worms feed on forest detritus., , Habitat use by different species:, Observe how different species of animals use various layers starting from the forest, floor, upwards along the trunk and branches, to the canopy of the trees. These species show that the forest habitat consists of various layers each forming a microhabitat, within the forest., Among the commoner insects, the termites build their homes out of mud present on, the forest floor. The large red fire ants build homes out of leaves in the tree canopy., Monkeys such as langurs and macaques use the tree canopy for leaves and fruit as, well as the forest floor, where they look for fallen flowers, buds and fruit., The leopard hunts on the forest floor for prey such as the barking deer, cheetal, and, hare., Eagles hunt for their small prey in trees and on the ground. Their prey consists of small, birds, rodents, snakes and frogs., The Giant squirrel is rarely ever seen on the ground. It looks for fruit and nuts by, crossing from one tree branch to another. It requires forests with an unbroken canopy., The rat snake is usually on the ground while the vine snake twines onto branches of, shrubs and trees. Both are non-poisonous., Birds like bee eaters and drongos catch insects while they fly through the canopy by, swooping through the branches. Babblers most often look for insects and worms by, disturbing the dead leaves on the forest floor., , Field Work, , Chapter8.p65, , 279, , 279, , 4/9/2004, 5:10 PM
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The hornbill looks for fruit in trees and makes a nest in a large hole after carefully, selecting a very tall old tree., The crow pheasant hunts for grasshoppers and worms on the forest floor and in trees., The shrews look for insect life underground., Millipedes, centipedes and scorpions move around on the forest floor. Many of these, animals live in holes under the ground, under rocks or among the dry leaves., , Environmental Studies for Undergraduate Courses, , 280, , Chapter8.p65, , 280, , 4/9/2004, 5:10 PM
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B. GRASSLAND, •, , A Field Visit To A Grassland:, , Observe the variety of plant and animal life in the grassland. Document the food used, by each animal that is identified., •, , Describe the seasonal changes in the grassland:, , Describe how the grassland would look in different seasons., Describe the anticipated changes in colour and the condition of grasses: growing phase,, flowering phase, dyeing phase, dry phase., •, , Abundance of grassland species:, , Try to count the number of grasshoppers that jump out of a disturbed 1sq.m quadrant, on the ground. Count at least 20 such quadrants. You may find this hard! Repeat the, count for ants, beetles etc. This will be nearly impossible, as there are just too many of, these insects. This will demonstrate the great abundance of insects in the grassland., Compare this to the much smaller number of first order consumers - birds and mammals that can be counted in the grassland. The predators, mammals and birds of prey, – raptors, are least abundant., •, , Birdwatching in grasslands:, , Make a checklist of common grassland birds by identifying them from the Book of, Indian Birds, by Salim Ali. Read what each species feeds on., •, , Observing the insect world:, , Observe how the ants live and collect food. Observe how beetles behave in the grassland. Observe the abundance of grasshoppers, beetles and ants. Compare this with, the number of their predators., •, , Observe a spider catch its prey:, , See the different types of webs. Tunnel web spiders make a tunnel and sit inside, waiting for prey, which are pulled in and eaten. Other spiders in the grassland make, small orbwebs that have radial and spiral threads. Some spiders build a colony which is, like a mass of web material., •, , Document animal behaviour:, , Make a general list of behavioural patterns of all the animals, birds and insects you see., What are they doing? How and where did you find them in the grass? What is their, relationship to the grassland as a habitat?, •, , Understanding grassland food chains:, , Identify as many plant and animal species. Use the list to form as many food chains as, possible., Field Work, , Chapter8.p65, , 281, , 281, , 4/9/2004, 5:10 PM
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C. DESERT AND SEMI ARID-AREAS, •, , Observe desert and semi-arid landscapes:, , Observe the sparse but specialised nature of vegetation in a desert or semi-arid landscape. Document the number of animal species that are seen in the vicinity. There are, very few compared with other types of ecosystems., •, , Observe the fauna of semi arid country:, , Identify the birds and insects which are most easily seen. Document how each species, is using its habitat. What do these species feed on in this harsh environment?, •, , Observe typical species such as dung beetles that roll dung into a ball in which they lay, their eggs so that their young get food., , •, , Observe birds of prey that use this ecosystem., , •, , There are rare birds in a few areas such as the Great Indian Bustard., , •, , There are rare mammals such as the wolf., , D. AQUATIC ECOSYSTEMS, •, , Document the nature of aquatic ecosystems:, , Visit an aquatic ecosystem such as a pond, lake, river or seacoast., Observe if the water is clean or polluted. A simple kit can be used to study water, quality., , 1. Studies on the ecology of a pond:, , Make observations on a seasonally active pond if possible on several occasions before,, during and after the monsoon. Document the seasonal changes in the plant and animal life., , Environmental Studies for Undergraduate Courses, , 282, , Chapter8.p65, , 282, , 4/9/2004, 5:10 PM
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Example: Guidelines for a writeup on a POND ecosystem, A pond is a highly dynamic mini ecosystem. It changes rapidly during the year. To study, a pond one should, as far as possible, cover all its phases. A monsoon phase, when the, pond changes from a dry to a wet (aquatic) state. It’s growing phase, when it is colonised, by microflora and fauna and then other forms of macroscopic life. At the height of the, monsoon, it is in a mature aquatic phase, which is full of life. Once the rain stops, the, pond begins to shrink. Its periphery becomes dry and is colonised by terrestrial plants, like grasses and herbs. As it shrinks, its aquatic flora and fauna dies, giving place to land, flora and fauna. Eventually it may only remain in the form of a ditch or depression, containing terrestrial forms and dormant aquatic invertebrates such as insects that must, await the next monsoon. This process, when repeated year after year, leads to a silting, up of the pond which eventually gets shallower and shallower and in the course of, time, gives place to a grassland, scrubland and after many decades to a forest. This is, the process of succession., , •, , •, , Observe the pond. What seasonal stage is it in?, , •, , What do you expect to occur over the next 3 months, 6 months, 9 months, 12, months?, , •, , What are the vegetation zones in the pond?, , •, , What species use the pond as a habitat?, , •, , Take some water from the pond and examine it under a microscope. What do you, see?, , •, , Describe the pond’s periphery – its soil, vegetation, fauna., , •, , Describe the pond’s floor – its soil, vegetation, fauna., , •, , Write a note on the food chains you observe., , Observe the vegetation zones at the waters edge:, , Observe the different zones of vegetation - grasses on the periphery, emergent reeds,, floating vegetation and underwater plants in the pond., •, , Seasonal field observations on a pond:, , Early stage - soon after the pond fills with water in the monsoon: Observe algae and, microscopic animals. These can be observed under the microscope., Fully active phase: Submerged and emergent vegetation – fish, frogs, snails, worms, and aquatic insects., Shrinking phase: Drying aquatic plant life with dead and dying plant material and, terrestrial plants growing on the exposed mud of the pond., Dry phase: Overgrown with grasses and shrubs with hidden dormant animals in the, mud, which cannot be seen., , Field Work, , Chapter8.p65, , 283, , 283, , 4/9/2004, 5:10 PM
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•, , Laboratory exploration:, , Observe water from the pond in a glass. Document its colour and what it contains., Observe water from a pond under the microscope. There are a large number of algae, and zooplankton that form the basic food chains of the aquatic ecosystem., , 2. Observations on a Lake ecosystem:, , Document the way in which different water birds use the various habitats both on the, shore and in the water. Each of the different species of aquatic birds shares its habitat, with only a few other species. Each species specialises in certain types of food and, feeds at different depths. The length of the legs of different wading birds is an indicator of the depth at which they feed. The length of their beaks indicates the depth of, mud or sand into which they can probe., •, , Diversity and abundance of life:, , Make a checklist of all the visible aquatic flora and fauna. Identify those that are most, abundant. Observe and document the food chains. Estimate or count the population, (abundance) of different species observed in the aquatic ecosystem., , 3. Observations at a wetland:, , Visit a Wetland. Observe the varied vegetation zones within the ecosystem. Document, and map its vegetation patterns – Underwater/ emergent/ floating/ none. Describe if, the water is clean or turbid. Describe the level of algal growth and weeds. What is the, nature of its bed – rocky/ sand/ silt/ mud/ mixed (in what proportion?). Develop a map, of the aquatic ecosystem vegetation and its relationship to species of aquatic birds., Ask local fishermen to show you their fish catch. Observe the ducks, waders and other, birds. These are most abundant in the winter as most of them are migrants from, across the Himalayas., , 4. Observation on a field visit to a beach:, , Beaches can be sandy, rocky, shell-covered or muddy. On each of these different types,, there are several specific species, which have evolved to occupy a separate niche., Observe all the different crustacea such as crabs that make holes in the sand., Observe how the various shore birds feed on their prey by probing into the sand., , 5. Observations at a river:, , Depending on the location of the river, the study can demonstrate its ecological status., The river is a dynamic system with seasonal fluctuations in flow rates that affect its, plant and animal aquatic life as well as along its banks. Observe and document how, life is dependent on the river’s integrity., Environmental Studies for Undergraduate Courses, , 284, , Chapter8.p65, , 284, , 4/9/2004, 5:10 PM
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Example: Guidelines for a write up on a RIVER ecosystem, A river is an aquatic ecosystem that is influenced by the monsoon. It may be a perennial, river, or one that runs dry after the rains. The river ecosystem has abiotic and biotic, components. While many of its species are aquatic, there are terrestrial species that use, its banks. Both these need water. Aquatic species live in the water, while the terrestrial, species live on the banks but are highly dependent on the proximity of water. Many, species such as amphibia and aquatic insects use both aquatic and terrestrial habitats., •, , Describe the aquatic ecosystem in the river water and the terrestrial ecosystem on, the riverbank., , •, , Describe the characteristics of the bed of the river, the depth of the water and the, flow rate in different sectors. Rapid, slow, stagnant., , •, , Describe the various habitats of different species of flora and fauna in and around, the river., , •, , Document what you see in the water under a microscope., , •, , Document how different species use the water and the banks of the river., , •, , Describe how each of the habitat parameters is linked with the species that live, there., , •, , Observe the food chains. Document aquatic food chains, terrestrial food chains on, the bank, and those in which both aquatic and terrestrial species occur., , Field Work, , Chapter8.p65, , 285, , 285, , 4/9/2004, 5:10 PM
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E. HILL/MOUNTAINS, The ecosystem of the hill you are observing is linked to its altitude, slope, soil characteristics, vegetation and animal life. It has different vegetation patterns that create specific, microhabitats for a variety of fauna. The habitat changes seasonally. What do you expect, will occur in three months, six months and nine months from the present scenario?, , Example: Guidelines for a write up on a HILL/ MOUNTAIN ecosystem, •, , Describe the hill – slope, soil, watercourses, etc., , •, , Describe its various plants and animals., , •, , Observe and document its food chains., , •, , Describe the water cycle, the nitrogen cycle, energy cycle, detritus cycle with specific reference to the hill/ mountain ecosystem., , •, , What would happen if all the domestic animals were to be prevented from grazing?, , •, , What would happen if ants were to be completely eliminated from this ecosystem?, , •, , What would happen if all the vegetation is removed from the slopes?, , Environmental Studies for Undergraduate Courses, , 286, , Chapter8.p65, , 286, , 4/9/2004, 5:10 PM
