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Note for Environment Studies - ENV By vaira vel

  • Environment Studies - ENV
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  • Anna university - ACEW
  • Chemical Engineering
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www.rejinpaul.com www.rejinpaul.com www.eeecube.blogspot.com CHAPTER 1 INTRODUCTION TO ENVIRONMENTAL STUDIES AND NATURAL RESOURCES 1.1 INTRODUCTION Environment French word Environ (Surroundings) eats E.g.: COW Dead animals nourishment PLANTS Dead Plants SOIL Nourishing matter Dead bodies 1.2 DEFINITIONS  Environment is derived from the French word Environ which means to encircle or surround.  Environment is sum total of water, air, and land, inter-relationships among themselves and also with the human beings, other living organisms and property. The above definition given in Environment Act, 1986 clearly indicates that environment includes all the physical and biological surroundings and their interactions. www.eeecube.blogspot.com Download Useful Materials from Rejinpaul.com

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www.rejinpaul.com www.rejinpaul.com www.eeecube.blogspot.com 1.3 SCOPE Scope of environmental science is broad. Some of the aspects of scope of environmental science are:  Studying the interrelationships among biotic and abiotic components for sustainable human ecosystem,  Carrying out impact analysis and environmental auditing for the further catastrophic activities,  Developing and curbing the pollution from existing and new industries,  Stopping the use of biological and nuclear weapons for destruction of human race,  Managing the unpredictable disasters and so on. There are some major issues like global warming, depletion of ozone layer, dwindling forests and energy resources, loss of global biodiversity etc., that are going to affect the mankind as a whole and for that we have to think globally. 1.4 NEED FOR PUBLIC AWARENESS  Public awareness very essential to help understand pros and cons of environmental problems.  The United Nations Conference on Environment and Development held in Rio de Janerio in 1992 and popularly known as Earth summit followed by the world www.eeecube.blogspot.com Download Useful Materials from Rejinpaul.com

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www.rejinpaul.com www.rejinpaul.com www.eeecube.blogspot.com      summit on sustainable Development in 2002, have highlighted key issues of global environmental concern. Environmental pollution cannot be removed by laws alone. The proper implementation and especially public participation are important aspects. Public participation is possible only when the public is aware about the ecological and environmental issues. A drive by the government to ban the littering of polythene cannot be successful until the public understands the environmental implications of the same. The public has to be educated about the fact that if we are degrading our environment we are actually harming ourselves. 1.5 NATURAL RESOURCES Natural resources (economically referred to as land or raw materials) occur naturally within environments that exist relatively undisturbed by mankind, in a natural form. 1.5.1 FOREST RESOURCES uses  Man depends heavily on a larger number of plant and animal products from forests for his daily needs.  The chief product that forests supply is wood, which is used as fuel, raw material for various industries as pulp, paper, newsprint, board, timber for furniture items, other uses as in packing articles, matches, sports goods etc.  Indian forests also supply minor products like gums, resins, dyes, tannins, fibers, etc.  Many of the plants are utilized in preparing medicines and drugs; Total worth of which is estimated to be more than $300 billion per year.  Many forests lands are used for mining, agriculture, grazing, and recreation and for development of dams. Depending upon the climate conditions, forest may be classified as:  Tropical Rain Forests: They are evergreen broadleaf forests found near the equator. They are characterized by high temperature, high humidity and high rainfall, all of which favor the growth of trees.  Tropical deciduous forests: They are found a little away from the equator and are characterized by a warm climate the year round. Rain occurs only during monsoon.  Tropical scrub forests: They are found in areas where the day season is even longer.  Temperate rain forests: They are found in temperate areas with adequate rainfall. These are dominated by trees like pines, firs, redwoods etc.  Temperate deciduous forests: They are found in areas with moderate temperatures. www.eeecube.blogspot.com Download Useful Materials from Rejinpaul.com

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www.rejinpaul.com www.rejinpaul.com www.eeecube.blogspot.com  Evergreen coniferous forests (Boreal Forests): They are found just south of arctic tundra. Here winters are long, cold and dry. Sunlight is available for a few hours only. Ecological uses The ecological services provided by our forests may be summed up as follows:  Production of Oxygen: The main green house gas carbon dioxide is absorbed by the forests as a raw material for photo synthesis. Thus forest canopy acts as a sink for carbon dioxide thereby reducing the problem of global warming caused by green house gas CO2  Wild life habitat: Forests are the homes of millions of wild animals and plants. About 7 million species are found in the tropical forests alone.  Regulation of hydrological Cycle: Forested watersheds act like giant sponges, absorbing the rainfall, slowing down the runoff. They control climate through transpiration of water and seed clouding.  Soil Conservation: Forests bind the soil particles tightly in their roots and prevent soil erosion. They also act as wind breakers.  Pollution moderators: Forests can absorb many toxic gases and can help in keeping the air pure and in preventing noise pollution. 1.5.2 over Exploitation of Forests  Man depends heavily on forests for food, medicine, shelter, wood and fuel.  With growing civilization the demands for raw material like timber, pulp, minerals, fuel wood etc. shot up resulting in large scale logging, mining, roadbuilding and clearing of forests.  Our forests contribute substantially to the national economy.  The international timber trade alone is worth over US $ 40 billion per year.  The devasting effects of deforestation in India include soil, water and wind erosion, estimated to cost over 16,400 cores every year. 1.5.3 Deforestation  Deforestation means destruction of forests. www.eeecube.blogspot.com Download Useful Materials from Rejinpaul.com

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