INTRODUCTION

    The human population is increasing at a very fast rate. Growth in population takes place in geometrical
    progression whereas increase in food production takes place in arthmetic progression as given below:
    Geometric Progression : 2 ® 4 ® 8 ® 16 ® 32 (Population growth)
    Arthmatic Progression : 2 ® 4 ® 6 ® 8 ® 10 (Increase in fond production)
    As is clear from the above figures, population grows at much faster rate than the increase in food production.
    As a result there is always an increase in demand for the basic requirements of man, that is, food, water, clothes and shelter.
   These requirements of man are fulfilled through the natural resources such as minerals, forests, groundwater, soil and through agriculture.
   For example, man uses wood obtained from forests as fuel as well as for construction of houses. Man uses ores obtained from the
   earth lithosphere for extracting metals. Coal, petroleum and natural gas are important resources of earth, which satisfy
   the energy requirements of man. The industrial revolution has created a greater demand for the various raw materials such as minerals,
   petroleum and coal than was ever required before. In order to satisfy the ever-increasing demands of food, water, clothing and shelter man
   has exploited the natural resources to such a greater extent that it is creating an ecological imbalance in nature.
    In this chapter we will discuss about management of our natural resources like forests, wildlife, water, coal and petroleum for sustainable
   development. Management of the natural resources is a global problem. There are various national and international laws,
    regulations and acts towards protecting our environment.

 

    NEED OF CONSERVATION

    With the coming up of advanced science and technology more and more natural resources are being used up. Old villages,
    hills etc., are being converted to cities. Agricultural landsare being used for constructing big hotels and industries.
    To generate electricity, more and more dams are being constructed. To maintain a balance between environment and
    development, there is a need for sustainable development. This means that present needs for development should be fulfilled
    in such a way that options for future generations are not closed. To achieve this various points have to be kept in mind.
    • Ecological balance has to be maintained.
    • Efficient use of resources has to be carried on.
    • Planting of more trees is required.
    • Conservation of various natural resource is must.
    • Green patches have to be interspersed between concrete buildings.
    • National parks should be established.
    • Preventing air, water and land pollution.
    • Proper disposal of wastes.

  CONSERVATION AND JUDICIOUS USE OF NATURAL RESOURCES

    Conservation is the wise and careful use of resources. It means not to control quantity of the resources but also
    to maintain their quality. It needs proper management of resources.
    It is possible to have a cleaner, less polluted and healthier environment through proper planning. 
    This is possible only if effective measures are taken to reduce the pollution and the various natural resources are used judiciously.

    All natural resources are classified into two categories :

    (A) Inexhaustible

    (B) Exhaustible.

    (A) INEXHAUSTIBLE RESOURCES are present in unlimited quantity and do not get exhausted by human activities,e.g.,
    solar energy, wind energy, rainfall, tidal energy, hydropower.
    (B) EXHAUSTIBLE RESOURCES have limited supply on earth and are of two types:

    • Renewable resources are those which have the capacity to reappear or replenish themselves by recycling or replacement
    within reasonable time, e.g., water, soil, natural vegetation, wildlife, aquatic animals.
    • Non-renewable resources are those which lack the ability of recycling and replacement, e.g., biological species, minerals.

    Renewable resources like forests and groundwater should be used only at the rate, as they are being replenished in nature.
    If we use renewable resources at a faster rate than they are being replenished, then it creates an imbalance and disturbs the environment adversely.
    Non-renewable resources must be used as sparingly as possible so that they remain available to us for a much longer period. Coal,
    petroleum, natural gas and minerals are some of the important 
   non-renewable resources. These should be used economically. Consumption of fossil fuels at a faster rate also pollutes the environment.

    FACTORS TO BE CONSIDERED FOR DEVELOPMENT OF RESOURCES

    • Management of resources should be done keeping in mind coming up generations. There should be equitable distribution
    of resources so that all get benefit from the development of these sources.
    • While exploiting natural resources we cause lot of damage to the environment e.g., Mining causes lot of pollution because
    of lots of water generated. There should be safe disposal of these wastes.
    To overcome various environmental problems of global concern, there are national, international laws and regulations.
    Various national and international organisations are working towards it. e.g., Kyoto Protocol, Ganga Action Plan.

    KYOTO PROTOCOL

    From December 1 to 11, 1997, more than 160 nations met in Kyoto, Japan to negotiate binding limitations on greenhouse gases
   for the developed nations, pursuant to the objectives of the Framework
   Convention on Climate Change of 1992. The outcome of the meeting was the Kyoto Protocol, in which the developed nations
   agreed to limit their greenhouse gas emissions, relative to the levels emitted in 1990. The United States agreed to reduce emissions
    from 1990 levels by 7 per cent during the periods 2008 to 2012.

    GANGA ACTION PLAN (GAP)

    • Ganga runs its course of over 2500 kms from Gangotri in the Himalayas to Ganga Sagar in the Bay of Bengal through 29 cities
    with population over 1,00,000 ('class-I cities'), 23 cities with population between 50,000 and 1,00,000 ('class-II cities'), and about 48 towns.
    It is a river with which the people of India are attached spiritually and emotionally. Department of Environment, in December 1984 prepared
    an action plan for immediate reduction of pollution load on the river Ganga.
    There was a need of Ganga Action Plan as quality of Ganga water reduced a lot. Ganga water had shown resence of coliform bacteria which
    are found in human intestine. Presence of these bacteria indicates contamination of water by disease causing bacteria.

    POTABLE WATER

    The dictionary definition of potable is a liquid that is suitable for drinking. People often ask themselves if their water is safe, but getting
    an answer isn't as simple as looking, tasting or even testing.
    Some rural people use the old age-If it smells and tastes like water and looks clean like water, then it's probably okay. Although taste,
   odour, colour, and clarity are important, they only address water's physical aspects. The bacteriological and chemical content of water should also be tested.

Fig.1_Total coliform count levels in Ganga during the years 1993-94

  If your water comes from a public water source such as a municipal water system, then your concern may be minimal as public water must meet,
 certain set criteria, before it can be used for human consumption. However, if your water is   esired level your water is a private source, such as your
 own well or digout, then it is your responsibility to determine whether the water you drink is truly "safe" for you and your family.
 Simple tests such as a bacteriological exam or a chemical analysis, only cover certain aspects of water. As well, each test may require different
 methods or equipment to complete the analysis. Therefore, you need to choose what tests are required. If you don't, then it's like going to buy "fluid"
 for your car. Unless you know exactly which one you need-washer, brake, gas, diesel-you may end up wasting your money on something you really
 don't need. Nor, is it easy to return a lab service.

    A general chemical analysis usually cover.s parameters such as
    • Iron            • Alkalinity
    • Magnesium and Manganese     • Potassium
    • Total Dissolved Solids (TDS)     • Hardness
    • Fluoride             • Sodium
    • Conductivity         • Sulphate
    • PH                • Nitrate and Nitrite (N)
    • Chloride             • Calcium
    • Turbidity

    pH MEASUREMENT 

    • pH measurement is the amount of alkalinity or acidity in water and water-containing fluids. For example, a pH of 1 indicates a
    strongly acidic solution, a pH of 7 indicates a neutral solution, and a pH of 14 indicates a strongly alkaline solution.
    • pH measurement can be made using a variety of techniques and equipment ranging from simple pH test strips to sophisticated electronic test meters. .
    • pH Test Strips or papers provide the means of obtaining qualitative or semi-quantitative results in seconds. They are ideal for rapid analysis or for
    applications that do not require highly accurate results. Simply dip the paper into the sample, remove and check for colour change.
    • pH Colour Cards. With pH colour cards, a coloured water sample is compared against a card; upon which are printed coloured standards.
    The user simply matches the colour by eye and reads the pH level directly from the card.
    • pH Test Meters. Highly accurate electronic pH test meters to assist plant engineers and managers in conducting regular, consistent and reliable
    testing of their water plant and systems.

    1.     When was Ganga Action plan started?
    2.    What are coliform bacteria?
    3.    What is recycling?

    USE OF THREE R'S TO SAVE ENVIRONMENT

    Although there are number of problems related to environment yet we can use three 'R' formula to save it.
    These three R's are:
    • Reduce Avoid waste--look for ways of producing and using goods that stop, waste being generated.
    Reduce waste--choose products that can be used productively, recycled in your area, and have minimal packaging.
    • Reuse Reuse containers, packaging or waste products.
    • Recycle Recycle waste material into useable products.
    • For Waste that can't be Avoided, Reused for Recycled. Treat the waste to make it less hazardous or reduce the volume of the
    hazardous component. Dispose of the waste safely.

    REDUCE

    The most effective way to help save the environment is to reduce your waste before it becomes rubbish.
    • Become informed about the environmental impacts of the products you buy. If you're not satisfied, search for better alternative.
    • Bulk buy when possible, but don't buy more than you can use.
    • Choose products with less packaging.
    • Choose products with recyclable or reusable packaging.
    • Carry reusable shopping bags or boxes.
    • Say 'no' to unnecessary plastic bags and other packaging.
    • Reuse plastic bags and all types of containers over and over again.
    • Buy quality goods that will last.
    • Encourage manufacturers to play their part.

    Buy Recycled Goods

    Recycled goods have already saved resources and raw materials and helped reduce the overall quantity of waste. Remember, '
    recycled' means the product is made partly or wholly from recycled materials and 'recyclable' means the product is capable of
    being recycled. If you don't make an effort to buy recycled goods, you're not really recycling.

    Reduce Energy and Water Use

    Reducing your waste also means saving resources. Reducing your energy consumption in the home by switching to high-efficiency
   fluorescent light bulbs, using cold water for washing and cooking efficiently.
   Large amounts of water can be saved at home by fixing leaking taps, using dual-flush toilets, running washing machines and dishwashers
   only when full, turning the tap off while cleaning your teeth, and using a control nozzle on your hose when washing the car or the dog.
   Design your garden to be water efficient.

    REUSE

    • Look for products in reusable, refillable or recyclable packaging when you shop.
    • Donate unwanted clothing, furniture and white goods to charities.
    • Enquire if goods can be repaired rather than replaced.
    • Hold a garage sale.
    • Use rechargeable batteries rather than single use batteries and ask your local council about how to dispose of batteries properly.
    • Use retreaded tyres if they are appropriate to your driving.
    • Use glass bottles and jars, plastic bags, aluminium foil and take away food containers over and over again before recycling or disposing of them.
    • Carry your lunch in a reusable container rather than disposable wrapping.
    • Reuse envelopes and use both sides of paper.

    RECYCLE

    Recycling recovers materials used in the home or in industry for further uses. You should only recycle after you've tried to reduce and reuse.
    Recycling has environmental, economic and social advantages.
    • Recycling-generates civic pride and environmental awareness.
    • Recycling helps prevent environmental pollution.
    • Recycling saves natural resources. 
    • Recycling conserves raw materials used in industry.
    • Making products from recycled ingredients often uses much less energy than producing the same      
   product from raw materials.
    • Recycling reduces the amount of material dumped in landfill sites and helps our waste disposal Goods 
   are used productively and prevented from becoming litter and garbage.
    
    1.     1985
    2.    They are harmless bacteria present in human intestine which can indicate the degree of sewage pollution of water e.g. E.coli.
    3.    Recycling is the processing of waste article and materials so as to form new products.

    CONSERVATION OF FORESTS AND STAKEHOLDERS

    Stakeholders are : 
    • People living in or around forests who are fully dependent on forests for their life. 
    • The Forest Department of Government—owners of the land and working to control the resources from forests. 
    • The Industrialists using forest produce but not dependent on the forests in anyone area. 
    • People involved in wildlife and nature conservation. Each of the above groups depends on forests in a different way.
    Local People Around Forests 
    • Use Bamboo to make huts. 
    • Use baskets for collecting and storing food materials. 
    • Use wood to make implements for agriculture, fishing and hunting. 
    • Do fishing and hunting in forests. 
    • Gather fruits, nuts and medicines from forests. 
    • Graze cattles in forests. 
    These people lived in forests for centuries and ensured sustainable use of resources. 
    The Forest Department of Government 
    • Later British took over most of the forest areas and exploited forests ruthlessly for their needs. 
    • Local people were forced to depend on smaller areas. 
    • Forests started becoming over exploited. 
    • After India became independent, Forest Department took over. 
    • Management practices ignored local needs and knowledge.
    • Large areas were cleared and were converted to monoculture of pine, teak or eucalyptus.
    • This lead to destruction of biodiversity in the area.
    • Needs of local people could no longer be met from such forests.
    • But these plantations worked as an important soUrce of revenue for the forest department.
    • These plantations are being used by industrialists to reveal timber, paper, lac and sports equipment.
    The lndustrialists
    • Forests provide raw material for various industries.
    • Industrialists have access to these raw materials at artificially low rates.
    • Industries have greater reach than local people.
    • Industrialists are not interested in sustainability of forests.
    • After cutting teak trees in one area, they shift to another.
    • They do not ensure that one particular area should yield optimum amount of some produce for all
       coming up generations.
    Nature and Wildlife Enthusiatics
    • They are not at all dependent on the forests.
    • They have realized the need to preserve biodiversity.
    • For example,. Bishnoi Community in Rajasthan take forest and wildlife conservation as a religious 
  tenet.
    • Amrita Devi Bishnoi, National Award for Wildlife Conservation has been instituted recently in the 
   memory of Amrita Devi Bishnoi who sacrificed her life alongwith 363 others in 1731 for protection of 
   'Khejri' trees in Khejrali Village near Jodhpur in Rajasthan.
    From above discussion, we can reach to the conclusion that by keeping local people out and using forests cannot prove to be successful in the long run.
    Forest have to be used sensibly keeping both environment and development sound.

    FORESTS AND ITS CONSERVATION
    Forests are one of the important natural renewable natural resource which is mainly composed of trees, shrubs or any other woody vegetation.
    About one third of total land is under forest cover. They are the store house of biodiversity (bacteria, fungi, ferns, flowering plants, nematodes,
    insects, birds, reptiles, etc.) and provide various services to mankind. Now, if trees are cut at the rate which exceeds their rate of replenishment,
    it disturbs the environment. It may lead to formation of deserts.
    In the ancient times, many parts of the earth had lush green forests. In 'order to meet the requirements of increasing population, the trees have
    been cut senselessly. Trees provide wood for fuel and as well as furniture and for building houses. Forests have also been cut to clear land for
    cultivation and for building house. Many industries such as paper industry, match industry depend upon forest wood. Forests play a major role
    in soil conservation and in maintaining the water cycle in nature.
1.  Roots of trees keep the topsoil bound and prevent it from being washed away through water erosion as well as through wind erosion.
2.  Forests are also natural habitat of wild animals and birds.
3.  Trees give on large amounts of water by the process of transpiration. This helps in formation of rain clouds and bringing fresh water to the earth.
4.  Forests help in maintaining oxygen and carbon dioxide levels.
5.  They also play important role in regulating the earth's temperature;
6.  Forests also act as saviour from various solar radiation;.
7.  Forests provide raw material for paper industry.
8.  Forests have various protective functions like prevention of draught, protection against wind, cold, noise, radiations and even conservation of soil and water.
9.  Forests are important for production of timber, bamboos, food" and wide variety of compounds like resins, alkaloids, essential oils,
     latex and various pharmaceutical products.
10. Forests regulate amourit of CO2 and O2, water, minerals, radiant energy, draughts, various geochemical cycles, atmospheric and temperature
      conditions and thus increaseenvirorunental values of the area.
11.  Forests help in reducing atmospheric pollution by checking SPM.

    Destruction of forests for human leeds disturbs the ecological balance. Various causes which are leading to cutting of more and more trees or deforestation are :
    • Explosion of human population, leading to increased demand of timber, fuel, paper, wood, etc.
    • Forest fires.
    • Overgrazing.
    • Forest storms, frost and heat also lead to deforestation.
    • Some insects and pests also destroy trees by eating up leaves and by spreading various diseases.
    • Large areas have been cleared for agriculture, housing, factories, roads and railway tracks.
    • Construction of roads along mountains is another cause of forest degradation.
    • Mining has also contributed in the large scale felling of trees.
    • Construction of dams and reservoirs.
    
    1.     What is conservation?
    2.    Name the stakeholders in forest.

    Consequences of Depletion of Forests
1.    Due to depletion of forests, rainfall in the region decreases and area may finally become a desert.
2.    Deforestation may also lead to frequent floods in the area.
3.    It destroys the natural habitat of wild animals and birds.
4.    It leads to topsoil erosion.
5.    It reduces soil fertility.
6.    Forests specially on mountains protect protection from floods by trapping and absorbing water and then slowly releasing it.
7.    Deforestation causes extinction ofvarious species resulting into a loss ofirreplacable resources.
8.    It also brings about regional and global climate changes which become warmer because of lack of humidity.
9.    It deprive human beings of the benefits of forest trees and animals.
10.    It threatens tribal people whose survival mainly depends on forests.

    Conservation of Forests
    Man can play an active role for the replenishment of forests.
1.    Silviculture is one of the major programmes started to replenish forests. Some of the benefits achieved through this programme are :
    • It has helped in preserving the environment by bringing more and more area under forests .
    • It produces large quantities of raw materials for various industries.
2.    Afforestation should be there in the areas which are unfit for agriculture, along highways and rivers.
3.    Awareness programmes should be there. A special programme of tree plantation called Van Mahotsava is held every year in our country.
       It should be made more popular.
4.    Pests and diseases can be controlled by using pesticides, fumigation and biological control method.
5.    Grazing by cattle should be discouraged.
6.    Forests should be protected from fire. Latest fire fighting equipment should be used to extinguish accidental forest fire. .
7.    Economize the use of timber, fuel, wood etc.
8.    We must find out alternate sources of fuel, e.g., solar energy.

    IMPORTANCE AND CONSERVATION OF WILDLIFE
    Wildlife is of great importance to us. Wildlife includes all animals which are not domesticated, 
     tamed and plants which are not cultivated. Importance of wildlife is being discussed here as under:
    • It forms links in the food chain.
    • It plays important role in formation and protection of soil.
    • It helps in natural recycling of materials.
    • It helps in maintaining gaseous composition of atmosphere.
    • It is a source of livelihood for many people.
    • It has aesthetic and cultural benefits as it provides good deal of fun and recreation e.g., 
    Bird watching, Pet keeping etc.
    • Many improved varieties of crops are developed through breeding programmes. Genes of wild species are used' to have better breeds.
    • There may be some unknown benefits. It is unpredictable that which species become useful in future, e.g., Penicillium and Cinchona.
    
    1. Conservation is protection and scientific management of a resource so as to maintain it is at 
        optimum level for providing benefits to present as well as future generation.
    2. Stakeholders connected with forest are local resident to next department, indistrialists and 
        wildlife, nature enthusiasts.

    CONSERVATION
    Large scale poaching by man poses a serious threat to the survival of many species of wildlife, both plants as well as animals.
    This can disrupt the food chains in which these animals occur. 
    Thus, it is very important to conserve wildlife. Some of the remedial measures then can be taken for the conservation of wildlife are below:
1. Natural habitat of the animals should be preserved. This can be achieved through increasing the area under forests and also through
    establishing large number of wildlife sanctuaries and national parks. Unauthorized felling of trees should be curbed as it destroys the habitat of animals.
     For every acre of forest cut down an equal area should be planted with saplings. Some of the National Parks and Bird Sanctuaries developed in our country are :
    • Gir National Park in Gujarat
    • Corbett National Park in Uttar Pradesh
    • Shivpuri National Park in Madhya Pradesh
    • Kanheri National Park III Maharashtra
    • Bharatpur Bird Sanctuary in Rajasthan.
2.    The number of wild animals should be regularly monitored in the wildlife sanctuaries. Special attention should be paid to the endangered species.
3.    Poaching should be totally banned. Rules should be framed so that poaching or killing of endangered species becomes a punishable offence under law.
4.    Species going towards extinction should be given importance over other conservation programmes.
5.    Protection of ecosystems can help in protection of species.
6.    Biosphere reserves deal with the conservation of ecosystems and the genetic resources contained therein. The biosphere reserves are a special
       category of protected area of land/or coastal environments wherein people are an integral component of the system.
7.    Besides insitu conservation (conservation in natural habitats), exsitu conservation (i.e., conservation away from natural habitats) can also help, e.g.,
       Botanical gardens, Zoological gardens, Aquaria, Seed banks, Gene banks.
8.    Various wildlife projects have been started to its conservation, e.g.,
    • Project tiger in 1973 to check reduction in the population of tiger.
    • Elephant project started in 1992.
9.    There should be proper survey of all forests to have approx. number of species in a specific area.
10.  There should be protection of habitats, food and shelter of endangered species.
    

    CHIPKO MOVEMENT
    Chipko movement i.e., "Hug the Trees Movement" is one of the movements in India to conserve biodiversity and to end the alienation of people
    from their forests which started in March, 1973. Sunderlal Bahuguna of Tehri and Chandi Prasad Bhatt of Gopeshwar are prominent leaders of this movement.
    It was Sunderlal Bahuguna who was able to transfer ecological perspective to Chipko. 
    Main objectives of chipko movement are :
    • To protect existing forest cover.
    • Afforestation.
    • To utilize forest wealth keeping in mind its conservation.
    • Leaders of chipko movement believes in food, fodder; fuel, -fertilizers and fibres.
    • Forests are must to protect environment and maintain ecological balance and should not· be disturbed. 
    
    A movement similar to chipko was started by Pandurang Hedge in South. It is known as Appiko movement which belieyes in conservation,
    plantation and rational use. As a result of chipko-movement :
    — Private contract system of felling trees was abolished. 
    — Commercial green felling in the Himalayan forests of Uttar Pradesh were banned. 
    — Felling of trees was stopped in the Western Ghats and the Vindhyas. 
    These movements originated in early 1970 in a remote village called Reni in Garhwal, high up in Himalayas. When . local villagers stopped felling
   of trees by a logging contractor. Women of the village clasped the tree trunks while men folk were absent. This prevented workers from felling the
   trees and inwarted contractor had to withdraw. Slowly with the spreading of these movements, people learnt priorities in the use of forest produce.
   In 1912, West Bengal Forest Department recognised its failures in the revival of the degraded sal forests in southwestern districts of the state.
   This had led to attention of people by the administration. Result was clash between forest officials and villagers. These conflicts were major factor
   in fuelling the militant peasant movements led by the Naxalities.
   Later the Department changed its strategy. In the Arbari forest range of Midnapore district, far seeing forest officer A.K Banerjee and villager got
   involved in the protection of 1,272 hectares of badly degraded sal forest.
    • Villager were given employment in the programme of, repleinishment of forests i.e., Silviculture and harvesting operations.
    • 25 percent of the final harvest.
    • Allowed fuel wood and fodder collection on payment of nominal fee.
    As a result of active participation of people mainly the local community, the sal forests of Arabari underwent a remarkable recovery by the year 1983.

    WATER FOR ALL
    Kulhs in Himachal Pradesh
    • Kulhs is a local system of canal irrigation which evolved about four hundred years ago in parts of 
   Himachal Pradesh.
    • Water from streams was diverted to man-made channels.
    • Those channels took water to many villages down the hill side.
    • There used to be common agreement between all the villages to manage the flowing water in Kulhs.
    • Village which was farthest was the first one to use water during planting season.
    • Then water was used up by villages progressively higher up.
    • Kulhs were managed by two or three people. They were paid by the villagers.
    • Besides above, water also percolated into the soil and fed springs at various points.
    • Later Kulhs were taken over by irrigation department which stepped sharing of water as before.
    Rains in India are in a few months of the year. Failure to sustain underground water av.ailability occurs as a result of :
    • Loss of vegetation cover
    • Diversion for high water demanding crops
    • Poilution from industrial effluents and urban wastes.
    To meet agricultural and daily needs of water throughout the year various dams, tanks and canals we used. Maintenance of irrigation systems etc.,
    was a local affair. Arrival of British led to, up coming of large dams which neglected local irrigation methods.

        
    DAMS
    A dam is a barrier built across a stream or river to hold and control the flow of water for useful purposes. There are several types of dams.
   The choice of dam is decided upon by examining foundation conditions, load strains, temperature and pressure changes,
   chemical characteristics of groundwater  and possible seismic activity.
   Historically, dams and the lakes have protected growing populations from the unpredictability and violence of rivers seasons.
   In some regions, stored flood waters can supply enough irrigation for a year-round growing season.
   Dams have been built with the intention to improve human quality of life by diverting water for power, navigation, and flood control,
   but have also resulted in human health concerns and environmental problems. Dams benefit people by providing usable, reliable water sources.
   Although there are numerable benefits of dams but construction of dams bring about lot of changes in the regional environment.
   It leads to ecological imbalance. Its impact at times is so much that changes cannot be reverted back. So it is very important to think about various alternatives to dams.

    DAMS : ADVANTAGES AND LIMITATIONS
    The mian purpose of dams is to improve human quality of life by providing drinking water and to support economic growth by diverting
     water for power, navigation, flood control and irrigation. Dams have succeeded for the same in various ways. Various advantages of dams are:
    • Provides supply of water for towns, cities and mining sites .
    • Provides supply of water for irrigation of crops.
    • Controls floods.
    • Contains and stores wastes (tailings) from mines.
    • Creates lakes for people to swim in and sail on and thus provides recreational opportunities.
    • Generates electricity in hydroelectric power stations.
    • Navigation.
    • Provides greater habitat diversity.
    • Controls the flow of water. 
      Although dams are multipurpose and beneficial for humans but they have some adverse effects also, as they disrupt ecosystems,
     decline fish stocks, force resettlements etc. 
     Dams change the chemical, physical and biological processes of river ecosystems as they alter 
     free-flowing systems by reducing river levels, there by blocking the flow of nutrients, changing water temperature and oxygen levels and
     preventing fish and wildlife migration. These changes  may be beneficial or tragic.
    Some of the disadvantages of dams are :
    • Dams lead to alterations in temperature and flow in the river downstream from the dam.
    • Loss of flowing water habitat and replacement with standing water (reservoir) habitat.
    • Interruption of animal movements along the course of the river.
    • Interruption of genetic exchange among populations inhabiting the river course.
    • Alteration of the fish community in the region of the river now inundated and upstream from the  
   reservoir.
    • Reduction in the delivery of river nutrients to downstream section of the river because of entrapment 
   by the reservoir.
    • Dams detract from natural settings, ruin nature's work.
    • Dams inundate the spawning grounds of fish.
    • Dams inhibit the seasonal migration of fish.
    • Dams threaten an endanger some species of fish and mussels.
    • Dams inundate various archaeological sites.
    • Reservoirs can foster diseases if not maintained significantly.
    • Reservoir water can evaporate significantly .
    • Some scientists believe that reservoirs can cause earthquakes.
    • Reservoir created by dam may inundate land resulting in the loss of crops, and cities.
    • People are displaced by the reservoir and have to find new homes.
    • Reservoir cause instability of hill slides.
    • Submerge places of green cultural and spiritual importance.
    • Cause earthquakes because of the weight of water in reservoirs.
    • Destroys marine fisheries because they disrupt river borne flows of fresh water and nutrient into 
  oceans.
    • Leads to coastal erosion .
    • Occasionally collapse and drown people. In the world's worst dam disaster-a mega-catastrophe that 
   struck China in 1975 when two large dams burst-as many as 2,30,000 people died.
    • Induce seismicity in previously a seismic regions.
    • Affects groundwater levels as seepage and evaporation from big lakes is significant.
    
    1.     Name two traditional water harvesting system.
    2.    Give one criticism about large dams.
    3.    What is the impact of excessive irrigation and intensification of agriculture?

    THE EFFECTS OF UNPLANNED TECHNOLOGICAL GROWTH
    Before starting any technological project, it is very important to consider the long term effects of the project on the environment.
   The unplanned technological growth in any area may disturb the delicate balance existing in the ecosystem.
    Few examples of unplanned technologies and mismanagement are :
    • Indira Gandhi Canal brought greenry to many areas of Rajasthan but inequitable distribution gh of water created problems.
     People closer to the source grow crops like sugarcane and rice which need lot of water. As a result, people downstream do not get any water.
    • Lot of problems are counting up as a result of raising the height of the Sardar Sarovar Dam be on the river Narmada. This has started
     with the protests by the Narmada Bachao Andolan (save the Narmada Movement).

    From the above instances, the importance of foresight and long term planning, before starting any project that interferes with nature, should become clear.
    Above discussion explains how poor tribal people gets affected from various development projects and three main problems arising as a result of large dams are :
1.  Social problems as it displaces large number of people without adequate rehabiliation.
2.  Economic problems as lot of public money is utilized without proper benefits.
3.  Environmental problems as it leads to deforestation and loss of biodiversity.
    
    1.  Kulh, Khadin
    2.  Large dams consume large amount of public money without the generation of proportionate benefits.
    3.  It has resulted in environmental degradation and creastion of few waste lands.
        Water logging has ultimately caused development of saline soil.

    WORLD COMMISSION ON DAMS
    In response to the growing opposition to large dams, the World Commission on Dams (WCD) was established by the World Bank and IUCN in 1998.
    The Commission's mandate was to :
    • review the development effectiveness of large dams and assess alternatives for water resources and energy development; and
    • develop internationally acceptable criteria, guidelines and standards for the planning, design, appraisal, construction, operation,
    monitoring and decommissioning of dams.
    The 12 Commissioners came from a variety of backgrounds, representing a broad spectrum of interests in large damsincluding governments
   and non-governmental organisations, dam operators and grass roots people's movements, corporations and academics, industry associations and consultants.
    Commission's final report was released in November 2000.

    ALTERNATIVES TO DAMS
    When a proposal to build a new dam is put forward two types of studies are usually carried out:
    • Firstly, the cost/benefit ratio of the dam project is calculated, i.e., does the value of the benefits that will be obtained by building the dam exceed the cost
    of building the dam? This study is intended to determine if the building of the dam is economically justified.
    • Secondly, the effect of the new dam on the environment is assessed in an Environmental Impact Statement (EIS).
    One question usually asked is; "Is a new dam really needed or could the objectives of the dam project be achieved in some way other than by building a new dam?"
    The answer to this question depends on what the objectives of the dam project are e.g., if the dam is to be built to meet the additional demand for water supply to
     a growing city it might be possible to meet this demand by obtaining water from another source, e.g., groundwater pumped from underground aquifers,
    or the demand for water might be reduced by, for instance, increasing the cost of water to the consumer. In either case, it might be decided that the
    construction of a new dam is not required after all.
    In the case of a dam which is to be built to generate electricity it might be similarly possible. to reduce demand by increasing cost or the electricity
    might be able to be generated in some other way, e.g., solar, coal fire or nuclear power stations. Obviously many factors, both economic and environmental,
    have to be considered before it can be decided, for example, whether a new dam or a new coal fire power station is more desirable.
    Dams do create some adverse environmental impacts and some high profile, large dam projects in the past are now thought by some to have caused
    unacceptable environmental damage. The environmental problems associated with dams can be successfully managed in the dam designing process so
    that they are less damaging to the environment.
    There are many different alternatives to dams depending on the purpose of the dam.

1.     AGRICULTURE, IRRlGATION AND WATER SUPPLY 
    Various alternatives to new storage dams that produce same amount of agricultural products using less water are :
    • Improved management of surface irrigation systems e.g., downstream control systems, channel 
   maintenance.
    • Selection of better field application practices e.g., 'bed and furrow' irrigation, or drip irrigation 
   instead of flood irrigation.
    • Encouraging a cropping pattern that is adjusted to the local climatic conditions e.g., growing sorghum 
   instead of rice or wheat in drought prone areas.
    • Enhancing local water storage in pond or lakes through small structures, connecting channels and 
  measures to encourage groundwater recharge, such as the traditional 'tank' system in Southern India.
    • Adopting water harvesting tachniques can provide an alternative to large reservoirs, or reduce the 
  volume of new storage required. In this chapter we will be discussing about this alternative way of 
  dams.
    Like agriculture various savings can be made in industry and domestic water use.
    • Leakage reduction programmes, which stabilise and reduce losses from piped systems.
    • Rainwater harveRting through rooftops, tanks and other methods.
    • Infiltration techniques to maintain groundwater levels in areas that have short but intensive rainy 
  seasons.
    • Reuse and recycling of water'.
    • Desalinisation, although current techniques are both expensive and energy intensive.

2.     ENERGY
    In case objective of the dam is to meet additional demand of energy like water supply, hydroelectricity then other alternatives to dams
    can be thought of. Use of renewable energy like solar energy, wind energy, ocean energy and biomass which are always available
    and non-polluting can prove to be useful. This can prevent large scale damage of environment.

3.     FLOOD MANAGEMENT
     Various alternatives to dam construction for flood control are always there.
    • Reducing the scale of floods through better catchment management, controlling run-off, and protection 
    of wetlands.
    • Isolation of flood threat by flood embankments, flood proofing and limiting flood-plain development.
    • Increasing people's coping capacity with emergency planning, forecasting, warnings, evacuation, 
   compensation and insurance.

        
    WATER HARVESTING

    Water is essential to all life forms on earth. Therefore adequate supplies of water have to be there to sustain such life.
    Development of water supplies should be undertaken so as to preserve the hydrological balance and the biological functions  of our ecosystems.
    Consequently, the human endeavour in the development of water sources must be within the capacity of nature to replenish and to sustain.
    If this is not taken care, it can lead to serious consequences. The application of innovative technologies and improvement of indigenous ones
    should therefore include management of the water sources to ensure sustainability and to safeguard the sources against pollution.
    Lot of work is being done by various organisations to rejuvenate ancient systems of water shed managenient as an alternative to mega projects like dams. 
    Main aim of water shed management is to develop primary resources of land and water without disturbing ecological imbalance. Water shed managment :
    • Increases the production and income of water shed community.
    • Migrates droughts and floods.
    • Increases the life of the downstream dam and reservoirs.
    Various indegenous water saving methods were used by communities as they:
    — dug small pits and lakes.
    — put in place simple water sned systems.
    — built small earthen dams.
    — constructed dykes, sand and limestone reservoirs.
    — set up rooftop water collecting units.
    All these methods helped in recharging groundwater levels.
    Water harvesting is very old concept in India. Some of the ways of water harvesting in different areas of India are :
1.  Rajasthan-Khadins, tanks and nadis. 
2.  Maharashtra-Bandharas and tals. 
3.  Madhya Pradesh and Uttar Pradesh-Bundhis.
4.  Jammu-Ponds in the Kandi belt.
5.  Tamil Nadu-Eris or tanks.
6.  Kerala-Surangams.
7.  Karnataka-Hattas.
     Rain Water harvesting is the activity of direct collection of rainwater, which can be stored for direct use or can be recharged into the groundwater.
    Water harvesting is the collection of run off-for productive purposes.

    Since the ultimate source of water that feeds all secondary sources is rain, therefore we need to understand the value of rain and make
    optimum use of rainwater at the place where it falls.

    NEED FOR RAIN WATER HARVESTING
    • Water is becoming scarce day by day. Therefore, there is need to attain self-sufficiency to fulfil 
   water needs.
    • Groundwater is getting depleted and polluted.
    • A urban water supply system is under tremendous pressure for supplying water to ever increasing population.
    • Soil erosion resulting from unchecked run-off.
    • Health hazards due to consumption of polluted water.

    METHODS OF WATER HARVESTING
    • Rainwater stored for direct use in above ground or overhead tanks and used directly for various purposes.
    • Recharged to ground through recharge pits, dug wells, bore wells, soak pits, recharge trenches etc.
    This is called groundwater recharge.

    BENEFITS OF WATER HARVESTING
    Water is a scarce natural resource in most regions of India. Water has to be piped over long distances from perennial sources to urban areas
    where efficiencies are low. Collection, storage and efficient use of rainwater can reduce the cost of public water supply.
    There are number of benefits of harvesting water. 
    • Provides self-sufficiency to water supply. 
    • Conserves valuable groundwater and reduces monthly water bill. 
    • Reduces the cost for pumping of groundwater. 
    • Reduces local flooding and drainage problems. 
    • Provides high quality water, soft and low in minerals. 
    • Flushes salt build up from soils. 
    • Reduces soil erosion. 
    • Decreases landscaping and property maintenance needs. 
    • Supplements water requirement during summers and drought. 
    • Provide excellent quality water for homes. 
    • Saves money and energy. 
    • Provides control over water source. 
    • Contributes to ecological cause. 
    • Reduces groundwater pollution. 
    • Rainwater harvesting systems are simple and can be adopted by individuals. 
    • In hilly terrains, rainwater is preferred. 
    • In coastal or saline areas, harvesting of rainwater provides good quality water and when recharged 
    to groundwater, reduces its salinity and also helps in maintaining balance between the fresh-saline 
    water.
    • In deserts, where rainfall is low, rainwater harvesting is very useful. Advantages of Rain Harvesting 
    over Mega Irrigation Projects 
    • It is a potential solution to problems of rural poverty and unemployment, resulting in an overall 
    improvement in the nation's economy., 
    • It gives high agricultural returns. 
    • It is sustainable due to decentralisation and community participation. 
    • Its installation and maintenance are cost and time effective. 
    On the contrary, Mega Irrigation Projects initiated during and after independence have the following disadvantages : 
    • They are capital intensive.     
    • They have long gestation periods. 
    • They give low agricultural returns. 
    • They face problems of silting.

    COMPONENTS OF WATER HARVESTING
    Water harvesting is mainly of two types :
    (A) Rainwater Harvesting. (B) Surface run-off harvesting.
    Harvesting system has following components.
    • Water collection from rooftops/open surface.
    • Filteration in case of surface run-off harvesting.
    • Storage in tanks.
    • Distribution.
    • Recharge the subsurface aquifers.
    • System maintenance.

Steps of roof top rainwater harvesting

(A) RAINWATER HARVESTING

1.    RAINWATER COLLECTION
      Rainwater can be captured from any rooftop. Collection efficiency depends on the size of catchment area, amount of rainfall and the design.
      Collected ·water is drained to the collection vessel through downpipes into the storage system.
2.   STORAGE
     Storage systems cab. vary in complexity on your needs. Storage may be in groundwater reservoir or tanks. A more involved systems include
     timed watering systems. Before storing water it should be made free from debris and leaves by placing screens over gutters (filtration).
    Water kept in tanks should be covered to minimize algal growth and eliminate the potential for mosquito breeding.

Fig. 2_Rainwater collection and storage

    Storage in Groundwater Reservoir
    • For rooftop rainwater harvesting through tubewells and handpumps, filter or desilting pit should be
    provided so that there is no silting of wells.
    • Such tubewells if pumped intennittently, increase the efficiency of recharge.
    • If groundwater reservoir is recharged through shaft, dug well etc., inverted filter may be provided.
    Storage in Tanks
    • A storage taIlk. should not be located close to a source of contamination, such as a septic tank etc.
    • A storage tank must be located on a lower level than the roof to ensure that it fills completely.
    • A rainwater system must include installation of an overflow pipe which empties into a nonflooding area.   
    Excess water may also be used for recharging the aquifer through dug well or abanduned handpump or 
    tubewell etc.
    • A speed breaker plate must be provided below inlet pipe in the filter so as not to disturb the flitering material.
    • Storage ·tanks should be accessible for cleaning.
    The inlet into the Storage tank should be screened in such a way that these can be cleaned regularly.
    • Water may be disinfected regularly before using for drinking purpose by chlorination or boiling etc.
    • Rainfall water containers. As an alternative to storage tanks, battery tanks 
    (i.e., interconnected tanks) made of pottery, ferrocement, or polyethylene may be suitable. 
    The polyethylene tanks are compact but have a large storage capacity (1000 to 2000 litre) are easy to clean and have
    many openings which can be fitted with fittings for connecting pipes.

3.     DISTRIBUTION
     Water stored can be distributed through regular drip irrigation system. Gutters or down spouts can be designed to catch rainwater
    and distribute directly to landscape plants. Even rainwater can be directed to rock lined trenches or perforated pipes and allowed to infiltrate into the soil.

Fig.3_Distribution of harvested water

4.     SYSTEM MAINTENANCE
    Water harvesting systems need to be maintained regularly. Debris screen over gutters should be cleaned and storage
   tanks should be drained and cleaned periodically.

(B) SURFACE RUN·OFF HARVESTING

    Rainwater harvesting using ground or land surface catchment areas is less complex way of collecting rainwater. It involves improving
    run-off capacity of the land surface through various techniques including collection or run-off with drain pipes and storage of collected water.
    Compared to rooftop catchment techniques, ground catchment techniques provide more opportunity for collecting water from a larger surface area.
    By retaining the flows (including flood flows) of small creeks and streams in small storage reservoirs (on surface or underground) created by low cost
   (e.g., earthen dams), this technology can meet water demands during dry periods. There is a possibility of high rates of water loss due to infiltration into
   the ground, and because of the of ten marginal quality of the water collected, this technique is mainly suitable for storing water for agricultural purposes.
   Various techniques available for increasing the run-off within ground catchment areas involve.

   • Clearing or altering vegetation cover. Clearing vegetation from the ground can increase surface 
   run-off but also can induce more soil erosion. Use of dense vegetation cover such as grass is usually suggested as it helps to both maintain an high rate
   of run-off and minimize soil erosion.

   • Increasing slope. Steeper slopes can allow rapid run-off of rainfall to the collector. However, the rate of run-off has to be controlled to minimise soil
     erosion from the catchment field. Use ecr of plastic sheets, asphalt or tiles alongwith slope can further increase efficiency by reducing both evaporative
     losses and soil erosion. The use of flat sheets of galvanized iron with timber frames to prevent corrosion was recommended and constructed in the
     State ofVictoria, Australia, about 65 years ago.

   • Soil compaction by physical means. This involves smoothing and compacting of soil surface using equipment such as graders and rollers.
   To increase the surface run-off and minimize soil erosion rates, conservation bench terraces are constructed along a slope perpendicular to runoff flow.
   The bench terraces are separated by the sloping collectors and provision is made for distributing the run-off evenly across the field strips as sheet flow.
   Excess flows are routed to a lower collector and stored.

    • Soil compaction by chemical treatments. In addition to clearing, shaping and compacting a catchment area, chemical applications with such soil
   treatments as sodium can significantly reduce the soil permeability. Use of aqueous solutions of a silicone (water repellent) is another technique for
   enhancing soil compaction technologies. Though soil penneability can be reduced through chemical treatments, soil compaction can induce greater
   rates of soil erosion and may be expensive. 
   Use of sodium-based chemicals may increase the salt content in the collected water, which may not be suitable both for drinking and irrigation purposes.
   The water harvesting structures in level terrain are crescent shaped earthens embankments (low) and straight concrete and rubble check dams built across
   seasonally floded gullies. Large structures provide water an the year round but smaller ones dry up after six months of monsoons. Water stored in dug wells
   is therefore more advantageous as it does not evaporate and also does not provide breeding grounds for mosquitoes. Groundwater is also protected from
   all kinds of contamination.

    Fig.4_Traditional (Khadin) water harvesting system
    Disadvantage of Rainwater Harvesting
    Disadvantages of rainwater harvesting technologies are mainly due to the limited supply and uncertainty of rainfall. Adoption of this technology
    requires a bottom up approach rather than the more usual 'top down' approach employed in other water resources development projects.
    This may make rainwater harvesting less attractive to some governmental agencies tasked with providing water supplies in developing countries,
    but the mobilization of local government and NGO resources can serve the same basic role in the development of rainwater-based schemes as water
     resources development agencies in the larger, more traditional public water supply schemes.

    FOSSIL FUELS
    Major part of our energy needs is being supplied by fossil fuels : coal, petroleum and natural gas. 
    Fossil fuels are the carbon containing substances that were formed from the remains of the organisms (plants and animals) that lived millions of
    years ago and were burried deep in the interior of the earth. Under the influence of high temperature and pressure and the absence of oxygen,
    these plant and animal remains were converted into fossil fuels. Large plants were converted into coal whereas small plants and animals were
    converted into petroleum and natural gas.
    Fossil fuels are energy rich molecules of carbon compounds which were originally made by plants with the help of solar energy. When fossil fuels are burnt,
    chemical energy stored in them long ago, from sunlight via photosynthesis is released. All fossil fuels yield CO2 and H2O as the products, on complete combustion.
    Fossil fuels are depletable or non-renewable sources of energy. They are being consumed at a rate much faster than the rate of their formation. So,
    they should be used with care and caution as these cannot be regenerated at the place of extraction.

    COAL AND ITS CONSERVATION
    Coal is naturally occurring black mineral which is a mIxture of free carbon and compounds of carbon containing carbon,
    hydrogen, oxygen, nitrogen and sulphur. It is not only a good fuel but is also a source of many organic compounds. Coal is believed to
    be formed from fossils which got burried inside the earth during earthquakes and volcanoes which occurred about 300 million years ago.
    Today we get coal from these ancient deposits. Minable coal is defined as 50 per cent of all coal which is in a seam of at least 12 inches
    thick and within 4000 feet at the surface. In India, coal is found mainly in Bihar, Orissa, Madhya Pradesh and West Bengal.

    USES OF COAL
    • It is used as a fuel.
    • It is used in the manufacture of coke.
    • It is used in producing energy in thermal· plants.
    • It is used in manufacture of synthetic petrol and synthetic natural gas.
    • It is used in manufacture of industrial fuel gases such as water gas.
    • It is a source of large number of organic aromatic compounds such as benzene, toluene, xylene, 
    phenol etc.

    CONSERVATION OF COAL
1.    Alternative sources of energy can be used e.g., Biogas.
2.    Thermal power plants use coal which produce lot of CO2, CO, S02 and nitrogen oxides. Therefore, some non-conventional sources
       can be thought of e.g., solar energy.
3.    Searching newer areas having fossil fuels.
4.    Protecting coal mines from accidental fires.
5.    Developing better techniques to extract fuel from depleting resources.
6.    Reducing wastage.
7.    Increase in generation of hydroelectric energy.
8.    Tidal waves of sea can be used to turn turbine and generate electricity.
9.    Use of biomass energy. This term is used for all materials originating from photosynthesis which includes live plant material, fresh and marine algae,
       agricultural and forest residues like, straw, bark, sawdust, husks, roots, animals wastes.
10.  Geo-thermal energy. In some places heated water comes out as hot springs. It can be used for heating water and buildings and for generating electricity.

    PETROLEUM AND ITS CONSERVATION

   Petroleum is also called rock oil (petra = rock, oleum = oil). It is a dark coloured liquid which occurs at various depths below the surface of the earth.
   The oil derived from oil wells is generally called mineral oil or crude oil. Petroleum is essentially a mixture of hydrocarbons mainly alkanes,
   cycloalkanes and aromatic hydrocarbons. Apart from hydrocarbons it maY also contain compounds containing oxygen and nitrogen.
   The exact composition of crude oil varies from one place to another and also from one field to another.
   According to modern view, the oil has been produced as a result of bacterial decomposition of the remains of animals and plants (under high pressure)
   which got burried under the sea, millions of years ago. The hydrocarbons formed by decay of the micro-organisms rise through porous rocks until they
   are trapped by impervious rocks. If the region is uplifted during the passage of time, the oil trap will be found to lie under land. Oil in these deposits
   generally floats over salt water. The oil in the petroleum field is generally covered with a gaseous mixture known as natural gas.
   The various components obtained from fractional distillation of petroleum are : asphalt (petroleum coke), lubricating oil, paraffin wax, fuel oil,
   diesel, kerosene, gasoline (petrol) and petroleum gas. 
   In India various oil refineries qre located at Barauni, Haldia, Chennai, Vishakhapattnam, Cochin, Mumbai, Digboi, Mathura, Guwahati and Koyali.

    USES OF PETROLEUM
    • Gasoline (petrol) is a motor fuel.
    • Diesel oil is fuel for diesel engines.
    • Fuel oil is a furnace fuel.
    • Kerosene is household fuel, illuminant fuel and jet engine fuel.
    • Lubricating oils are used for lubrication of machinery.
    • Paraffin wax is used in manufacture of candles, water proofing, vaseline, fabrics.
    • Petroleum coke can be used as a fuel and electrodes.
    • Petroleum gas is used as a gaseous fuel, production of carbon black, hydrogen and carbon monoxide (used to make ammonia and methanol)
    and gasoline by polymerisation.

    CONSERVATION OF PETROLEUM
    Besides judicious use of oil and petroleum we can start thinking about other substitutes.
    • Melvin Calvin was the first person to identify few plants whose products can be used in place of petrol and oil. The plants are able to convert
    substantial amount of photosynthates into latex which contains long chained liquid hydrocarbons which can be used directly or broken to hydrocarbons
   of chain length similar to ones in petrol. Various petroleum products can be obtaJned by cracking also.
    • Even ethanol can be used as a fuel. In Brazil, alcohol is being used as motor fuel. Alcohol can be used as a fuel for automobiles either as 10-15
    per cent blended with petrol or as entire fuel. Mixture is called gasohol. The crops which can be used for the production of alcohol are called energy crops.
    • Continuous improvement in fuel efficiency of automobiles.
    • Developing solar power machines and vehicles.
    • To work on battery operated vehicles.
    • Proper maintenance of vehicles.
    • Regular cleaning of air filters. 
    To conclude we can say that, if coal and petroleum undergo complete combustion CO2, H2O, oxides of nitrogen and sulphur are released.
    If incomplete combustion in insufficient oxygen occur, it leads to formation of carbon monoxide instead of carbon dioxide which is more harmful.
    Increase in carbon dioxide brings about greenhouse effect and global warming. Therefore, we need to use these resources i.e., coal and petroleum judiciously.
    Presently Euro I and Euro II norms for emission from vehicles are working towards reducing air pollution.

    EURO NORMS
    •  EURO I & II Emission norms are prescribed CO (Carbon Monoxide), HC (Hydrocarbons) and NO (Nitrous oxide) levels set by the government
    which a vehicle would emit when running on roads. All the manufacturers need to implement the same for vehicles being manufactured
   from the date of implementation. .
    • Euro norms refer to the permissible emission levels from both petrol and diesel vehicles, which have been implemented in Europe.
    However in India, the government has adopted the Euro norms for available fuel quality and the method of testing. Euro-I norms in India are known
   as INDIA 2000 since it will be implemented from 1/4/2000. The norms equivalent to Euro-2 are called 2005 norms but these have not yet been
   specified by the Indian Government.
    • The Euro norms require manufacturers to reduce the existing polluting emission levels in a more efficient manner by making certain technical changes.
    • The following changes normally will be made by manufacturers in order to have a EURO I compliant car. Typically, the following areas would require
   attention: (a) carburetor retuning (b) secondary air intake (c) exhaust gas recirculation (d) catalyser capacity increase (e) trimetal coating in the catalyser.
    • Changes for having a Euro II compliant vehicle require that the carburetor be replaced by an MPFI system i.e., a Multi-point Fuel Injection System.
    • There are two basic types of engines, spark ignition and compression ignition engines. In the former, fuel ignition is triggered by an electric spark
    from a spark plug, while in the latter, atomized liquid fuel is injected with the help of a fuel pump and a nozzle into a cylinder full of hot compressed air,
    which results in ignition taking place. Larger cylinders which need more fuel require more than one injector, thus resulting in a multi-point fuel injection system.

    SUSTAINABILITY OF NATURAL RESOURCES
    The last few decades have seen an increasing realisation that the current pattern of development and consumption is unsustainable.
    In other words, the increasing burden we are placing on the world's natural resources and environmental systems cannot go on forever.
    Environmental problems such as climate change, the economic challenges of increasing energy prices and social issues like 25,000
    people dying everyday from drinking polluted water are all examples of how we are living far beyond the capacity of the environment.
    It is clear that many of the decisions we make will have an impact on everyone, both today and in the future. As we continue to develop
    it is important to do so in a way that meets everyone's needs without compromising the ability of future generations to meet their own needs.
   This is the concept of Sustainable Development : achieving social and economic progress while protecting and enhancing the environement.
    In Securing the Future for Sustainable Development, there are four priority areas for action
    • Sustainable consumption and production.
    • Climate change and energy.
    • Natural resources protection and environmental enhancement.
    • Sustainable communities. 

    Sustainability is defined as meeting the needs of present generation without compromising the ability of future generations to meet their own needs.
    It is the intersection between three concentric circles: ecology, economy and society. 
    History of resource use has been a story of exploitation :
    • Exterminating species.                  •  Over-developing lands capes.
    • Formation of dams on rivers.        •  Polluting air.
    • OVer-cutting timber.                     •  Contaminating water etc.
    • Over-harverting fish.

    Sustainability means finding a way to accommodate our human needs without damaging the environment and even restoring damaged
    ecosystems so that they function somewhat like they once did. To do this we should try to :
    • Use renewable resources like wind, solar energy, instead of non-renewable resources like fossil fuels.
    • Use those resources which cause less harm to the environment.
    • Cut back on the amount of natural resources specifically non-renewable resources we used, by 
    reducing, reusing and recycling.

    SUSTAINABLE FOREST MANAGEMENT
    Forests and Climate Change
    There is great concern that increasing levels of carbon dioxide and other greenhouse gases in the atmosphere are causing changes in the global climate.
    Forests are considered natural 'carbon sinks because trees absorb carbon dioxide from the atmosphere as they grow, releasing oxygen and storing the
    carbon in their leaves and wood. Infact forests are a bit like a giant global air-purifier. They take carbon dioxide and turn it into wood and release
    clean oxygen for us humans and other animaL to breathe.
    Once a tree has been harvested, it ceases to absorb any more carbon dioxide. If the tree is bumeri or left to rot on the forest floor, this carbon dioxide
    will be released back into the atmosphere over time However, newly regenerated or replanted trees will continue to absorb the carbon dioxide from
    the atmosphere again. Also, once the tree is made into wood products, like timber or paper, these products continue to store the absorbed carbon.
    This is another important reason for ensuring that timber and paper products are recycled whenever possible, instead of being placed into landfill.
    Sustainable forest management includes :
    • All timber production for domestic consumption and export should come from sustainabl; managed natural forests.
    • Regular monitoring of timber harvesting practices.
    • More efficient wood use.
    • Recycling.
    • Promoting lower levels of consumption.
    • Expose forest harvesting malpractices.

    SUSTAINABLE CONSERVATION OF BIODIVERSITY
    Biodiversity conservation is an investment that yields substantial local, national and global benefits. As a part of the larger effort to achieve
    sustainable development, conserving biodiversity requires fundamental changes in patterns and practices of economic development worldwide.
    Biodiversity conservation can be sustained only if.
    • Public awareness and concern are substantially heightened.
    • Action to conserve biodiversity is planned and implemented at a scale determined by ecological and social criteria.
    • There is in increased public participation.
    • There is more integrative protected area management.
    • Active participation ofpopulations inside and around conservation sites, protected area allocation according to ecological representatives.
    • There is establishment of wildlife corridors.
    • There is combination of both exsitu (Conservation outside their natural habitats) and insitu. (Conservation in natural habitats) conservation.
    • There is commitment and support from Govt. and private sectors.

    WATER RESOURCES AND HYDROELECTRIC PROJECTS
    The environmental consequences ofwater resources-related projects are a matter of great concern. Although hydroelectricity has many advantages,
    yet there are few set-backs. The increase of water level might provide a better habitat for fist but can destroy habitat of humans by flooding of land. 
    In addition flooding can cause soil erosion, show impact on the vegetation of the area and cities located downstream.
    Therefore there should be: .
    • Proper Planning phases of hydroprojects.
    • Environmentally sustainable dam building.
    • Water harvesting.
    • Rural development" efforts on water quality and quantity.
    • Thinking of alternatives to dams. 
    A sufficient and sustainable supply of electricity to the world's population is one of today's greatest challenges. The current system of electricity production,
   including a 17% contribution of hydropower, is failing large parts ofthe population. Close to 2 billion people have no access to electricity, and on top of that,
   the reliance on fossil fuels such as coal, gas and oil is rapidly leading to climate change. 
   Energy efficiency and renewable energy sources are the way forward. Yet the role ofhydropower is not without controversy.

    RENEWABLE ENERGY AND HYDROPOWER
    Renewable energy is produced by transforming the natural energy flows of the Earth such as the sun, water, wind and biomass.
    These sources are permanently available and are non-polluting.
    But in the case of large hydropower stations, is renewable energy truly sustainable?
    The scale of the environmental damage created by the construction and operation of some hydropower stations is such that they
    should not be described as sustainable. And hydropower is not always emission free : it has been shown that shallow reservoirs
    in the tropics can emit substantial amounts of carbon dioxide and methane, two important greenhouse gases.
    Besides the environmental impacts, the social and economic risks can be enormous. In developing countries in particular,
    the poorest people rarely bebefit from large-scale hydropower dams. Instead, dams are often planned for export of electricity.
    The debate on hydropower and renewables is ongoing.
    There are often better, cheaper, less-destructive alternatives to building a large dam, whether to meet energy or water needs.
    These alternatives—from small-scale, decentralized water supply and new renewables, to large-scale efficiency and
    conservation options—have frequently been ignored.

Q.1  What changes can you make in your habits to become more environment friendly?
Ans. The most important means to make our havits more environment friendly are the three R’s, i.e., Reduce, Recycle and Reuse.
    (a)      Reduce: The best thing is to reduce consumption andprevent wastage.
         (i) Switch off the electric appliances whennot inuse.
        (ii) We should check regularly the leaking taps to avoid wastage of water.
        (iii) Reducing the wastage of food.
        (iv) Use public transport for travelling instead of using private cars.
        (v)  Use bicycle for visits to the market or neighbourhood.
    (b)    Recycle: We should do separation of recyclable wastes from non-recyclable wastes. Recycling saves resources and helps to
    conserve environmentin many ways.
    (c)    Resuse: Use reusable articles again and again. For example, carry bags, packing materials, palstic containers and other
    reusable articles should not be dump away if they are uncontaminated and reusable.

Q.2    What would be the advantages of exploitingresources with shortterm aims?
Ans.   Exploiting the resources with aiming short term benefits provide immediate advantages which can only meet our current needs.
          To overcome over exploitation of resources we msut
    (i) reduce ourbasic needs
    (ii) avoid excessive use of food, water and other consumable items
    (iii) avoid using non-biodegradable items
    (iv) save electricity

Q.3    How would these advantages differ from the advantages of using a long term perspective in managing our resources?
Ans.  Short term exploitation of natural resources meets the current demand and are beneficial only for the present generation
          but long term management of resources is aimed to fulfil the needs of future generations. Long term management of 
          resources can be achieved by their sustainable use.

Q.4    Why do you think there should be equitable distribution ofresources? What forces wouldbe working against an equitable distribution of our resources?
Ans.   Equitable distribution of resources will ensure benefits to poor as well as rich both kinds of people. 
          The  criteria for distribution mustbe made insuch a way that the people who get abundant resources must not waste them. In our Country,
          money and power are two major factors which hinders the equal distribution of resources. Powerful and rich people take benefit of their
         influence and try to encroach upon the shares of poor people.

Q.5    Why should we conserve forests and wildlife?
Ans.  There are economic and ecological reasons to conserve forests and wildlife. Economically forests are a good source of shelter, food,
          fodder and other valuable products like drugs, dyes and resins to people living in or out of the forests. Wildlife is useful for performing
          scientific research and used as gene bank for improvement of domesticated plants and animals. Ecologically they maintain the ecological
        balance of environment.

Q.6    Suggests some approaches towards the conservation of forests.
Ans.  Some approaches regarding forest conservation are:
    (i) Afforestation and reforestation 
    (ii) Controlled grazing
    (iii) Social forestry 
    (iv) Agroforestry 
    (v) Urban forestry
    (vi) Plantation of indigenous or exotic species to developforests in all available land.
    (vii) Indiscriminate felling of trees for the purpose of timber mustbe reduced.
    (viii) Prevention of scraping and litter removal.
    (ix) Building of national parks, sanctuaries andbiosphere reserves.

Q.7    Findout about the traditional systems ofwater harvesting management in your region.
Ans.  The traditional system of water harvesting! management in our region are pits, lakes, ponds, ditches and wet land.
         These reservoirs store rainwater that is used for various purposes like agriculture, drinking and also help in recharge of ground water.

Q.8    Compare the above system with the probable system in hilly/mountainous areas or plains or plateau region.
Ans.   Inhilly/mountainous areas, check dams are constmcted which are totally different from lakes and ponds as they store running water
          that is diverted to the required place. They are built across seasonally flooded gullies. The water in check dams does not remain stagnant
          for long hence they do not provide breeding grounds for mosquitoes and they do not get easily polluted by humans and animal wastes.

Q.9    Find out the sources of water in your region/locality. Is water from this source available to all people livingin that area?
Ans.  In our locality, water is available for people through two major sources:
    (i) The water is supplied by municipal corporation through pipes. Itis obtained from rivers/canals. In many cases, piped water is
     pumped from groundby tube wells and stored in raised water tanks.
   (ii) The poor people obtain water through hand pumps.

Q.10    What changes would you suggest inyour home in order to be environment friendly?
Ans. (i)  Switching off lights and other electrical appliances if not required
        (ii)  Use energy efficient lamps (CFLs) instead oftraditional filament bulbs
       (iii)  Use solar cookers, solar systems and solar heaters inplace of electrical appliances
       (iv)  Avoid using plastic bags and non-biodegradable materials
       (v)   Increasing reuse of containers
       (vi)  Separation of recyclable wastes from non-cyclable wastes prior to disposal

Q.11    Can you suggest some changes in yourschoolwhichwould make itenvironment friendly?
Ans. (i) Grow trees all around the play grounds along with boundary wall in school
        (ii) Make arrangement for water harvesting which can easily be managed at the roofs of classrooms
       (iii) School buses should run on CNG instead of diesel
       (iv) The fallen leaves of trees should be collected and converted into compost
       (v) Install solar energy panels to produce electricity
       (vi) Arrange awareness programmes among students through poster exhibitions and lectures

Q.12    We saw in this chapter that there are four main stake holders when it comes to forest and wildlife.
            Which among these should have the authority to decide the management of forest produce? Why do you think so?
Ans.    The people living in and around the forest area should have the authority to decide the management of forest produce
            because the local people are well aware of the practices to use the resources in sustainable manner. These people have been
           using the forest resources since ancient times without harming or causing any environmental damage because they are aware
           that excessive use of forest produce will be detrimental for their ownsurvival.

Q.13    How can you as an individual contribute or make a difference to the management of
          (a) forest and wildlife
         (b) waterresources
         (c) coal and petroleum?
Ans. (a)     For preserving forest and wildlife, I will not allow the cutting of trees and stop using animal products. I will make extensive
         campaigns for awareness among common people about the significance of forests and wildlife through various means.
        (b)     I will use water judiciously and prevent the wastage of water. I will also adopt the various possible water harvesting systems.
        (c)     I will try to minimise the use of coal in my house and suggest my friends and relatives to use nonpolluting fuels.
        (d)     I will use bicycle for shorter distances instead of motor vehicles. I will prefer public conveyance to save petroleum.

Q.14    What can you as an individual do to reduce your consumption of the various natural resources?
Ans.    As an individual, I will adopt these measures to reduce the consumption of natural resources
       (i) Use energy efficient CFL's instead of filament type electric bulbs
      (ii) Switch off the electrical appliances when not in use
      (iii) Prevent excess wastage of food
      (iv) Prevent wastage of water by getting the leaking taps repaired
      (v) Prefer to use renewable sources of energy
      (vi) Use solar energy to conserve fossil fuels
     (vii) Prefer to use the stairs instead of lift

Q.15    List five things you have done over the last one week to
        (a) conserve our natural resources
        (b) increase the pressure on our natural resources
Ans.    Answer to this should be givenby students according to their activities of last one week.
    Hints:
    (a) (i) I have not wasted food. (ii) I have used public vehicles instead of using own car. (iii) Reduced consumption of water by
    closing the tap to prevent over flow of water in bucket. (iv) I used only as much of electricity as was required.
    (v) I convinced my mother to use solar cooker for cooking food.
    (b) (i) I went to market by car instead of bicycle. (ii) I did not close the tap while brushing my teeth.
    (iii )  forgot to switch off my room lights last two nights. (iv) I asked my gardener to bum dry leaves anu polythenebags.
    (v) I used washing machine dryer to dry wetclothes.

Q.16    On the basis of the issues raised in this chapter, what changes would you incorporate in your lifestyle
           in a move towards a sustainable use of our resources?
Ans. (i) Follow the principles of three Re-reduce, recycle and reuse
       (ii) Walk or use the cycle to cover shorter distances
       (iii) Use stairs for 3 or 4 floors instead of use of a lift
       (iv) Use more'Warm clothes in winter rather using room heaters
       (v) Stop using products made from animal skin
      (vi) Use CFL's instead of traditional filament type bulbs
      (vii) Use solar cookers and solar water heater
      (viii) Stop using polythene bags and other non-biodegradable wastes
      (ix) Undertake tree plantation twice a year

MULTIPLE CHOICE QUESTIONS
1.    Major programme to replenish forests is :
      (A) Silvisulture       
      (B) Monoculture    
      (C) Agriculture       
      (D) Apiculture

2.   Deforestation causes :
      (A) Soil erosion  
      (B) More floods
      (C) Rainfall      
      (D) All the above

3.   If all the plants of the earth die suddenly all the animals die due to deficiency of :
      (A) Food           
      (B) Shade
      (C) Oxygen      
      (D) Shelter

4.  The concept of 'Biosphere Reserve' was evolved by :
     (A) UNESCO     
     (B) Govt. of India
     (C) Botanical Survey of India  
     (D) Zoological Survey of India

5.   the area reserved for the welfare of wildlife is called :
     (A) National park     
     (B) Botanical garden
     (C) Sanctuary     
     (D) Forest

6.  Chipko movement is concerned with :    
     (A) Forest conservation      
     (B) Plant breeding
     (C) conservation of natural resoures 
     (D) Project tiger

7.   Animals and plants are best protected in :
     (A) Zoos          
     (B) Botanical gardens
     (C) National parks     
     (D) Sanctuaries

8.   New approach to conservation is the establish ment of :
    (A) Sanctuaries      
    (B) Biosphere reserves
    (C) National parks    
    (D) Reserve forests

9.   Forests and wildlife are :
     (A) Renewable resources     
     (B) Non-renewable resources
     (C) Inexhaustible      
     (D) None of these

10.  Fossil fuels and metallic minerals are :
     (A) Renewable resources        
     (B) Inexhaustible resources
     (C) Non-renewable resources  
     (D) None of these

11.  The biomass fuel which is burned to release energy can be :
     (A) Solid only    
     (B) Liquid only
     (C) Both solid and liquid    
     (D) Solid, liquid and gas

12. Which group of vertebrates comprises the highest number of species ?
     (A) Birds          
     (B) Mammals
     (C) Fishes       
     (D) Reptiles.

13.  In our country percentage of land under forest is about:
      (A) 20%           
      (B) 19%
      (C) 25%           
      (D) 30%

14.  Wildlife is destroyed mostly by :
      (A) Lack of proper care    
      (B) Mass sGale hunting
      (C) Destruction of natural habitats    
      (D) Natural calamity.

15.  Deforestation may reduce the chances of :
      (A) Frequent cyclones   
      (B) Soil erosion
      (C) Rainfall      
      (D) Landslides.

FILL IN THE BLANKS
1.    Most biotic resources are .................
2.    Deforestation causes ................. of plant, animal and microbial species.
3.    Resources which can be replenished are called .............. .
4.     ................. is one of the programmes started to replenish forests. 
5.    Bharatpur bird sanctuary is in ................. .
6.    Three fossil fuels are coal, petroleum and
7.    ................. is also known as rock oil.
    

MULTIPLE CHOICE QUESTIONS
1.    B    2.    B    3.     C    4.    A    5.    A    6.    A    7.    C    
8.    B    9.     A    10.     C    11.     D    12.    B    13.    C    14.    C
15.     C        

FILL IN THE BLANKS
1.    Renewable         2.     Depletion          3.     Renewable resources     4.     Silviculture    
5.    Rajasthan          6.    Natural gas         7.    Petroleum 

VERY SHORT ANSWER QUESTIONS
1.    What is silviculture ?
2.    Define conservation.
3.    Name one national park and one bird sanctuary developed in our country to protect wildlife, rare animals and birds.
4.    When was project tiger started ?
5.    What are fossil fuels? Name any two fossil fuels.
6.    Name any two constituents 'of petroleum which are not used as fuels.
7.    Name two major elements present in coal.
8.    Write another name for petroleum.
9.    Name one of the prominent leaders of chipko movement.
10.    Who was Amrita Devi Bishnoi ?

SHORT ANSWER QUESTIONS
1.    Why is replenishment of forests necessary ?
2.    How do forests affect the water cycle ?
3.    Discuss various benefits achieved through silviculture.
4.    What is potable water ? State any four of its necessary characteristics.
5.    Differentiate between arithmetic progression and geometric progression in terms of food and population.
    
LONG ANSWER QUESTIONS
1.    Discuss various effects of unplanned technological growth.
2.    Are there any alternatives to dams ? Discuss.

Answers

Exercise-III

    1.    (A)    2.    (A)    3.    (A)    4.    (A)    5.    (D)    
    6.    (A)    7.    (B)    8.    (A)    9.    (B)    10.  (B)    
   11.   (C)   12.   (C)    13.  (A)   14.   (C)    15.   (D)    
   16.   (A)   17.   (D)   18.   (D)   19.   (B)    20.  (B)

Exercise-IV

Section-A
    1. Sustainable development     2. Conservation        
    3. Monoculture    4. Wild life conservation        
    5. Hug the tree movement    6. Convention on international trade in endangered species
    7. Recharge the ground water    8. CO.
    9. Efficiency of our machines    10. sulpher & Nitrogen

Section-B
    1.     (C)    2.     (C)    3.     (D)    4.     (D)       5.     (C)

Section-C
    1.     (A, B)    2.     (A, B,C)    3.     (A, B, C)    4.     (A, B)

Section-D
    1.     (A)    2.     (B)    3.     (C)

Section-E
    1.    (A)-(S), (B)-(P), (C)-(Q), (D)-(R)            2.    (A)-(Q), (B)-(P), (C)-(R), (D)-(S)

1.   Environment is formed of :
     (A) Only biotic components      
     (B) Only abiotic components
     (C) Both of these                    
     (D) None of these

2.   BOD stands for:
    (A) Biological oxygen demand             
    (B) Biochemical oxygen demand
    (C) Biochemical organic decomposition          
    (D) Biological organic decomposition

3.   Environment day falls on:
      (A) 28th February      
      (B) 23rd March      
      (C) 5th June          
      (D) 16th September

4.  Development with both intragenerational and intergenerational quality is called:
    (A) Sustainable development            
    (B) Unsustainable development
    (C) Economic development          
    (D) Sustainable consumption

5.  Sustainable consumption can be achieved by:
    (A) 3-R approach                  
    (B) Reducing the use of fossil fuels
    (C) By using alterative sources of energy  
    (D) All of these

6.   Joint forest management is an example of :
     (A) Political equality            
     (B) Participatory approach
     (C) Food stabilization                      
     (D) Economic equality

7.  Chipko movement was led by :
    (A) KM. Munshi                      
    (B) Sunder Lal Bahuguna
    (C) Panduranga Hegde                  
    (D) Menaka Gandhi

8.  Which form of coal is hardest and with maximum carbon content ?
     (A) Lignite          
     (B) Peat                
     (C) Anthracite        
     (D) Pearl

9.   Which of the following is an inexhaustible natural resources?
      (A) Forests      
      (B) Minerals          
      (C) Coal          
      (D) Water

10.  Which of the following is an exhaustible natural resources?
      (A) Solar radiation    
      (B) Air                
      (C) Minerals      
      (D) Water

11.  The quality of environment can be improved by
      (A) Deforestation                      
      (B) Overuse of natural environment
      (C) Erosion                                
      (D) Conservation

12.  Maximum petroleum is used in
      (A) Agriculture      
      (B) Shipping            
      (C) Industries      
      (D) Transportation

13.  Deforestation causes
      (A) Soil erosion        
      (B) Pollution            
      (C) No floods        
      (D) None of these

14.  Ecological imbalance in the biosphere is created by
      (A) Cutting of forests                     
      (B) Conservation of forest
      (C) Production of more paper              
      (D) Both (A) and (C)

15.  Floods can be prevented by
      (A) Cutting the forests 
      (B) Afforestation      
      (C) Tilling the land    
      (D) Removing the top soil

16. Ganga Action Plan was started in
      (A) 1975                
      (B) 1985            
      (C) 1995          
      (D) 2005

17. Which of the following are the stakeholders of the forests?
      (A) Local people      
      (B) Industries          
      (C) The government        
      (D) All of the these

18.  Amrita Devi Bishnoi National Award is rendered for
      (A) water conservation    
      (B) wildlife conservation
      (C) soil conservation    
      (D) none of these

19. Chipko movement was started in
      (A) Uttarakhand            
      (B) Himachal Pradesh     
      (C) Uttar Pradesh        
      (D) Madhya Pradesh

20.  Arabari project was started in 1972 in
      (A) Bihar                
      (B) Maharashtra      
      (C) West Bengal            
      (D) Delhi

21.  Who was the mastermind of Arabari project?
      (A) Sunderlal Bahuguna.  
      (B) Jyoti Basu      
      (C) A.K. Banerjee      
      (D) None of these

22.   One of the world’s most critical watersheds are found in
       (A) Himalayas            
       (B) Aravali          
       (C) Vindhyachal.            
       (D) None of these

23.  Khadin system of water harvesting is found in
      (A) Rajasthan          
      (B) Himachal Pradesh  
      (C) Haryana            
      (D) Gujarat