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A., , Tick (, 1., , B., , (a), , 3., , (d), , 4., , (d), , solid, , 2., , infiltration, , 3., , 22nd March, , 4., , Bawri, , 2., , F, , F, , 3., , T, , 4., , F, , 5., , Very Short Answer Questions., 1., 2., , E., , 2., , State whether the following statements are true (T) or false (F)., 1., , D., , (b), , Fill in the blanks., 1., , C., , the correct options., , (a) lce, , (b) Steam, The upper limit of ground water is called water table., , 3., , Minimum amount of water per person per day as recommended by the, United Nations for various basic needs is 50 litres., , 4., , Drip irrigation and sprinkler irrigation are the modern methods of, irrigation will conserve the water resources., , Short Answer Type-1 Questions., , 1., , It is because this water is salty or saline. Therefore, it is unfit for human, , consumption., 2., , The huge reservoirs of water inside the earth, formed by the collection, of groundwater between the layers of hard rock below the water table, are called aquifers., , 3., , The bawris are being revived due to the acute shortage of water., The three factors which depletes the water table at a place are-, , 4., , ), , increase in population, , (ii), , increase in, , (i), , increase in industries, , agricultural activities
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5., , F, , Drip irrigation is a technique of watering plants by making use of a, system of narrow pipes or tubes with small holes which deliver drop by, , drop directly around the roots., Short Answer Type-l Questions., 1., , The process of collecting rainwater from roofs and street corners and, storing it for later use is called rainwater harvesting., Two advantages of rainwater harvesting are-, , (), , The water table, , can, , be raised, , by rainwater harvesting, , (i) It reduces flood and top soil erosion., , 2, , 3., , The natural source of water contains many impurities. Following steps, are involved to remove these impurities., , )sedimentation, , (i) filteration, , (ii) aeration, , (iv) chlorination, , a) Saving water is important for us because the supply of clean and, fresh water is depleting at an alarming rate in some regions and we, , may suffer from moderate to severe water crisis in the coming years., (b) Concern for the society and needs of people., 4., , The continuous circulation of water from the earth's surface and water, , bodies as water vapour to the atmosphere and from the atmosphere, back to the earth's surface as rain, hail and snow is called the water, cycle in nature., , The processes involved in water cycle are, , 5., , G., , (i) Evaporation, (ii) Transpiration, (ii) Condensation, iv) Preciptation, Effects of water scarcity:, ), Non-availability of food, (i) Non-availability of oxygen for breathing, (ii) Lesser rainfall, , Long Answer Questions., 1., , Following are the factors which deplete water table at a place, (i), , Increase in population: Human population is increasing day by, day. To meet the needs of an ever increasing population, more, , houses, offices, school, shops and roads are being build. These, construction activities require huge supply of water. Boring made, at the construction site withdraws more and more ground water, which leads to depletion of water table., (i) Increase in industries: The number of industries are also increasing, continuously so more water is used by industries leading to, , depletion of water table.
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(ii) Increase in agricultural activities: The demand for agricultural, food crop has also increased due to increasing population. A, majority of farmers depend on rainwater to grow crops. But due to, unpredictable rainfall, they depend on irrigation methods. In many, places, the canal system may suffer from the lack of water due to, erratic rainfal. Nowadays, farmers use large quantities of ground, water by digging deep tube wells to cultivate crops. This results, depletion of water table., , (iv) Deforestation: Cutting down a large number of trees at a place is, called deforestation. This leads to failure of soil to hold moisture., The water just runs off on the ground surface., 2., , The following steps can be taken for proper management of water, (i), , Rainwater harvesting: In this method, water is collected in, percolation pits and recharge wells so as to recharge ground water., This is an ideal solution to water problem in areas with inadequate, water resources., , (ii), , Prevention of wastage of water: Wastage of water in households, commercial buildings, schools and public places can be prevented by, closing taps when not in use, repairing any leakage from pipes, etc., , (ii) Revival of bawris: Bawris are the ancient practice of water storage, and water recharge system in India. They provide water to the, people during drought periods. Due to the acute water shortage, faced by the people in some places, the bawris are being renovated, and revived., (iv) Drip lIrrigation: It is a technique of watering plants by making use, of system of narrow pipes or tubes with small holes which deliver, water drop by drop directly around the roots. Thus, the wastage of, water is avoided. This system allow the farmers to produce a high, yield with very little water.