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te term ‘conservation’ means ‘the process of keeping and protecting something from damage’., So, the conservation of plants and animals means that plants and animals which occur in the, a way that they remain protected in the natural environment in, which they are found. Be go further and discuss the conservation of plants and animals in, the meanings of some new terms such as biosphere, wildlife, biodiversity,, , , , , , forests should be kept, , , , detail, we should kr, , , , , , pter, apt, , and ecosystem whic, Biosphere is that part of the earth in which living organisms exist (or which supports life)., rf ft here of the earth, as well as water bodies on the, , 1 oceans). This is because living organisms are found on land, in the, , , , Biosphere includes, earth (like rivers, pc, atmosphere as well, , The «, , , , iral environment (like forests, etc.) are called wild animals. The wild, animals are not domesticatec man. The plants growing in the natural environment on their own,, are called wild plants. The wild plants are not cultivated (or grown) by man. The term ‘wildlife’, means all the animals and plants which are found naturally in the forests and other natural, habitats. Though the term ‘wildlife’ also includes wild plants but it is most commonly used for wild, animals and br, The term ‘diversity’ means ‘a variety’. And ‘biodiversity’ means ‘biological variety’. Biodiversity, Tefers to the variety of organisms (plants, animals and micro-organisms, etc.) found in a particular, area or habitat. in other words, the presence of a large number of species in a particular area (or, habitat) is called its biodiversity. Biodiversity denotes the richness of species in a particular area or, habitat., e An ecosystem is a ‘system’ which includes all the living organisms (plants, animals and micro_ Organisms) of an area and the physical environment (soil, air and water) in which they live. In an, the various living organisms interact among themselves (through food chains), and also, 109, , , , s livi

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(110) w awarens, 10 . AWARENESS SCIENCE FOR EIGHTH CLASS, , with the physical environment in which they live. An ecosystem is a self-sustaining nt of hiv,, Organisms and non-living environment, needing only the input of sunlight energy " functioning ‘, The wild animals and birds are comfortable and flourish in their own, natural habitat (which is Usual, a forest). The biggest threat to the existence and survival of wild animals and birds (or Wildlife, ic, deforestation, Let us discuss deforestation first., , DEFORESTATION AND ITS CAUSES, , The clearing of forests (by cutting down forest trees) over a wide area is called deforestation, The, forest land cleared of trees is used for other purposes. The various causes of deforestation (or Cutting dovin, of forest trees) are the following :, , (i) The forest trees are cut down to obtain wood, for using as fuel., , (ii) The forest trees are cut down to obtain wood, (timber) for making doors, windows and, furniture., , (iii) The forest trees are cut down to obtain wood, for making paper., , (iv) The forest trees are cut down to obtain more, agricultural land for cultivation of crops for the, increasing population., , (2) The forest trees are cut down to get land for, building houses, factories, roads and dams, etc., , All the above causes of deforestation are the, man-made causes of deforestation. There are also, natural causes of deforestation (which involve the destruction of forests by natural processes). Some of the, natural causes of deforestation are : Forest fires and Severe droughts. Forest fires can burn down all the, trees and other vegetation of the forest and cause deforestation. And when severe droughts occur, the forest, trees die out because of lack of water. A great variety of organisms like plants and animals exist on the, earth. These plants and animals are essential for the well-being and survival of mankind. Today, a major, threat to the survival of organisms (plants and animals) on the earth is deforestation., , , , Figure 1. Cutting down of trees of the forests on a large, scale is called deforestation., , Consequences of Deforestation, The destruction of forests by the excessive cutting down of forest trees can make the forests disappear, completely one day. The deforestation (or destruction of forests) will have the following, consequences fo:, , us, other animals and the environment :, , () Deforestation will lead to a shortage of wood and other forest products, , The wood obtained from forest trees is used as a fuel ; for making doors, windows and furniture; at, for making paper. Deforestation will lead to a shortage of wood for all these Purposes. Forests also give, useful products such as honey, gum, sealing wax (lac) and catechu, etc. We will also face shortage of 2!, these forest products if we continue to cut down forest trees., , (ii) Deforestation will cause an increase in temperature of earth's atmosphere leading to, global warming, Trees (and other plants) use carbon dioxide gas from the atmosphere for the process of food called ‘photosynthesis’. When a lot of trees are cut down during deforestation, then lesser number of i, will be left. The lesser number of trees will use up less carbon dioxide due to which the amount of ca tk, dioxide in the atmosphere will increase. In this way, deforestation increases the level of carbon dioxide 1", , atmosphere.

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wo CONSE 0 MALS m [111, carbon dioxide gas trang ERVATION OF PLANTS AND ANIMA\, , he sun’, apping of heat rays by carbon gi Sun's heat, , : ide j "AYS reflected b, pal warming. The 8tadual jn, . Ncreases the tempera, , ee nouse effect caused by the in €ase in © over-all te, , ger eng. The global warmi “teased leve], , warming. qT © 8 arming can Melt polar ; Of carbon, , jeading t0 @ tise in the sea Jeyoy, [ Ice caps rapidh, , led, , 3 le, juge loss of life and Property, “lsed sea-water level, i, ji) Deforestation Will cause Ss, | The roots of trees (and othe, , y the earth (causing greenhouse effect)., ture of earth’s atmosphere. This will lead to, ‘Mperature of earth’s atmosphere due to, dioxide in the atmosphere is called global, Y producing a tremendous amount of water, will flood the low-lying coastal areas causing, ‘Oil i P, , : Plane making the soil infertile and lead to desertification, narticles, the wind and wate, are not ables © Particles of top soil together. Due to this binding of soil, sposion. The tree cover also soft, ® carry away the top soil easily. In this way, trees prevent soil, , Ns the i, i effect of heavy rains On the forest soil due to which the top soil does, IS another way, , e loose quickly. This, , not become 100: sae is ! A, When the forest trees are cut down during dienes the forest help prevent soil erosion., , , there ar, , i hich can bind the, soil agi mien Prevent them from eing carried away by strong winds or Renan rain water., eit se quickly b a Wee cover On the soil to Soften the effect of heavy rains, the bare top soil, becomes “a a . ythe force of falling rain water and erodes rapidly. Thus, fewer trees result in more, soil erosion. i © oh =p of soil is the most fertile. The removal of top layer of soil during soil erosion,, exposes the weil, ere and Tocky layer of soil, This lower layer of soil has less humus and it is less fertile. Plants, donot grow well in this less fertile Soil. Gradua y, the fertile land gets converted into a desert. The process, by which fertile land becom, i led desertification, Thus, deforestation is the cause of, desertification., , amount of rain water which tushes quickly into rivers and, the percolation of rain water into, Tested soil rushes into the tivers quickly, causing floods. In this, i capacity of soil which leads 0 floods. Another reason for the floods, ion. The eroded soil is carried by flowing rain water into rivers. The, iver bed and decreases the depth of rivers gradually. Due to, , is reduced. When heavy rains occur, the Tiver is, not able to carry away all the rain water quickly. The excess water overflows from the banks of the river, , into the adjoining areas causing floods. These floods damage standing crops, houses and even drown, , () Deforestation affects the waier cycle leading to decrease in rainf, , rainfall lowers the groundwater level and could cause droughts, , The forest trees put a lot of groundwater, sucked through their roots, into the re as wal, vapour by the Process of transpiration (evaporation from the leaves). This Water vapour helps in bringing, Tain in that area. When the forest trees are cut down, then the lesser number of trees put less water vapour, into atmosphere through transpiration. Since less water vapour is put into the atmosphere, there is less, ‘ainfall in that area. When there is less rainfall in an area, then less water Percolates into the ground. Due, ‘0 this, the groundwater level also gets lowered. The shortage of surface water (in ponds, lakes, ete) and, Stoundwater due to persistent low rainfall in an area can lead to droughts (A prolonged Period of, “normally low rainfall leading to severe shortage of water is called drought). From the above discussion, We Conclude that as a consequence of deforestation, there will be increased chances of natural calamities such as, Mods and droughts,, , 7) Deforestation leads to the extinction of many wild animals and plants, Forest the natural habitats of many wild animals, birds as well as plants. When forest trees and, S are the natura, , all. The decrease in, , atmosphere as water, , , , co

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a AWARENESS SCIENCE FOR EIGHTH CLASS, , the natural habi, uman beings and get, not get enoug, or vanish) from that are:, , forest also get destroyed., one hand and leads to floods on the, , das follows : Deforestation reduces, , birds gets destroyed. These, killed. Moreover, in the absence of forest trees, h food and starve to death. In this way, many, a. When forests are cleared during, , other forest plants are cut down, tat of wild animals and, homeless wild animals fall prey to h, and plants, the wild animals and birds do, animal and bird species become extinct (, deforestation, many wild plant varieties growing in the, We have just studied that deforestation reduces rainfall on the, , other. These are two contradictory situations which can be explaine! , ant) through Sanspieal, rainfall because less groundwater is put into the atmosphere (as water vap on,, , . ‘ soil i duced, and (ii) so;, Deforestation leads to floods because : (i) percolation of rain water into the na we eae soil, eroded by rain water deposits on the river bed and decreases its water-carryin& P : now, , discuss the conservation of forests and wildlife., CONSERVATION OF FORESTS AND WILDLIFE, We have just studied that one of the adverse effects of deforestation (large scale cutting down of forest, trees) is the destruction of natural habitats of wild animals (and birds). So, deforestation poses a serious, large scale poaching (killing) of, , threat to the survival of wild animals and their natural environment. The ‘ N, wild animals residing in the forests by man (to obtain their skin, etc.) is also a big threat to ie survival of, many animal and bird species. The death or killing of wild animals disturbs the food chains in which these, , animals take part, resulting in undesirable consequences for the whole ecosystem. We should conserve, forests and wildlife to preserve biodiversity (variety of species), to prevent endangered species from, becoming extinct, and to maintain ecological balance in nature. Some of the measures which can be taken, for the conservation of forests and wildlife are given below :, , (i) The unauthorised felling (cutting) of forest trees for timber trade and fire-wood should be stopped, immediately. This is because depletion of forests destroys the natural habitats of wild animals and birds,, poses them to the cruelty of man as well as nature., , (ii) Incase of Government authorised felling of forest trees, for every acre of forest cut down, an equal, area of land should be planted with saplings of trees to make up for the loss in the long run., , (iii) The natural habitats of wild animals should be preserved by establishing conservation areas such, ere Reserves, Wildlife Sanctuaries and National Parks where the wild animals can flourish in, , and ex, , as Biosph, natural surroundings protected from the outside world., (iv) A total ban should be imposed on the poaching (killing) or capturing of any wild animal or bird., , Biosphere Reserves, Wildlife Sanctuaries and National Parks, There are three types of protected areas which have been established (or earmarked) by the, Government for the conservation of forests and wild animals. These are :, (i) Biosphere Reserves,, (ii) Wildlife Sanctuaries, and, (iii) National Parks., , Biosphere Reserves, Wildlife Sanctuaries and National Parks are the areas protected by law which have, been established throughout our country for the conservation of plants and animals (flora and fauna), present in the area. The human activities such as cutting of forest trees, cultivation of crops, plantations,, grazing of cattle, hunting and poaching of wild animals are prohibited (not allowed) in these protected, areas. The purpose of establishing several Biosphere Reserves, Wildlife Sanctuaries and National Parks, in India is to conserve wild animals and their natural surroundings (such as forests) so as to maintain 4, healthy balance in nature, and to prevent the extinction of endangered wild animals. We will now, discuss Biosphere Reserves, Wildlife Sanctuaries and National Parks in detail, one by ane

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CONSERVATION OF PLANTS AND ANIMALS [113, , BIOSPHERE RESERVE, , Biosphere Reserve jg, , i raat, and the traditional we Protected area of land meant for the conservation of wildlife,, bio ervation called Biosp} Mestyle of the tribal People living in the area. In creating the large areas, of cons s been kept in min igh = Reserves, the need of local people to have access to the resources of this, area ha “90, a special feature of the Protected areas called Biosphere Reserves is that, , eople or tribals are an j, oe ay and economic mae wee (necessary part) of it. Thus, Biosphere Reserves jointly manage, piod Y: We will now describe the basic design of a Biosphere Reserve., , A Biosphere Reserve jg a very la, a Te conservati wt ee ase . . gore,, puffer zone and transition Zone (see Figure 2) ton area which is divided into three zones : core, , (i) The innermost zone of a Biosph, . ere Re: i H e, ot Biosphere Reserve is devoted Serve is known as core zone (see Figure 2). The core zon:, , to strict rotection ildli we . _, i a ic activity), js allowed in the core zone of a Biosphere Resean of wildlife. No human activity (or economi y, , , , , , , , Core zone ° Biosphere, (only protection Reserve, of wildlife;, no human \, activity) > BO, ! \, i | \, ‘4 1, i L Z woo, Butter zone—— SO j, (research, 4 NS </—Transition zone, environmental *s, an 7 (human settlements;, education and = a oe cultivation of crops), tourism) MS a ‘Human, — settlements, , , , Figure 2. Design of a Biosphere Reserve., , (ii) The middle zone of a Biosphere Reserve is called buffer zone (:, , see Figure 2). Buffer zone, surrounds the core zone. In the buffer zone only limited human activity (, , compatible with conservation) is, allowed. For example, research, environmental education and tourism are allowed in the buffer zone of a, Biosphere Reserve., , (iii) The outermost zone of a Biosphere Reserve is called transition zone (see Figure 2). In the, transition zone, several non-destructive human activities such as settlements (houses) of tribals and, cultivation of crops, etc., are allowed which are necessary to sustain the life of tribals., , Some tribal people live in the outermost zone (transition zone) of a Biosphere Reserve who depend on, the local natural resources to fulfil the various needs of life. Ina Biosphere Reserve, the conservation of, wildlife and biodiversity are combined with the sustainable use of natural resources for the benefit of local, people (called tribals). No commercial exploitation of natural resources is allowed in a Biosphere Reserve., , A Biosphere Reserve may also contain other protected areas in it, For example, a Biosphere Reserve, may contain Wildlife Sanctuary and/or National Park in it. Biosphere Reserves are open to tourists up to, the buffer zone. No tourists are allowed in the core zone of a Biosphere Reserve, There are 14 Biosphere, Reserves in India. The names and locations of some of the Biosphere Reserves of India are given below:, , 1. Great Nicobar Biosphere Reserve (Andaman and Nicobar), , 2. Kaziranga Biosphere Reserve (Assam), , 3. Sunderbans Biosphere Reserve (West Bengal), , 4. Kanha Biosphere Reserve (Madhya Pradesh), , 5. Pachmarhi Biosphere Reserve (Madhya Pradesh)