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Chapter – 17, Forests: Our Lifeline, •, , Forest: Large area of land thickly covered with trees, bushes, etc., , •, , We get various products from the forests surrounding us., , •, , Forest is a system comprising various plants, animals and micro-organisms., , •, , In a forest, trees form the uppermost layer, followed by shrubs. The herbs form the lowest, layer of vegetation., , •, , Different layers of vegetation provide food and shelter for animals, birds and insects., , •, , The various components of the forest are interdependent on one another., , •, , The forest keeps on growing and changing, and can regenerate., , •, , In the forest, there is interaction between soil, water, air and living organisms., , •, , Forests protect the soil from erosion., , •, , Soil helps forests to grow and regenerate., , •, , Forests are the lifeline for the forest-dwelling communities., , •, , Forests influence climate, water cycle and air quality., , •, , Importance of Forests:, , •, , (i), , Provide timber., , (ii), , Purify air., , (iii), , Provide shelter., , (iv), , Prevent soil erosion., , (v), , Control floods., , (vi), , Noise absorbers., , Independence of Plants and Animals in Forest:, (i), , Plnats and animals depends on each other to remain alive., , (ii), , All organisms interact with each other and their physical environment to derive, energy and survive., , •, , Conservation of Forest:, (i), , Amount of carbon dioxide in air will increase, resulting in the increase of earth’s, temperature., , (ii), , Animals will not get food and shelter.

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•, , •, , (iii), , Soil will not hold water, which will cause floods., , (iv), , Endanger lives and environment., , Conservation of Forests:, (i), , Do not allow overgrazing., , (ii), , Promote afforestation., , (iii), , Protect wildlife., , (iv), , Control forest fires., , Food Chain: Interdependence between producers and consumers studied in form of various, linkage that appears as a chain., , •, , Food Web: A system of interdependent food chains used to represent various relationships, of organisms.