Evs Theory

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Unit IENVIRONMENT, ECOSYSTEMS AND BIODIVERSITY

Environment: Definition: The natural environment, encompasses all living and non-living things occurring naturally on Earth or someregion thereof. The concept of the natural environment can be distinguished by components:

• Complete ecological units that function as natural systems without massive human intervention, including all

vegetation, microorganisms, soil, rocks, atmosphere and natural phenomena that occur within their boundaries.

•

Universal natural resources and physical phenomena that lack clear-cut boundaries, such as air , water , and climate,as well as energy, radiation, electric charge, and magnetism, not originating from human activity.

Scope of Environment: The environment consists of four segments as under:. !tmosphere: The atmosphere implies the protective blanket of gases, surrounding the earth:

"a#$t sustains life on the earth."b#$t saves it from the hostile environment of outer space."c#$t absorbs most of the cosmic rays from outer space and a ma%or portion of the electromagnetic radiation from the sun."d#$t transmits only here ultraviolet, visible, near infrared radiation "&'' to ()'' nm# and radio waves. "'.* to *' m#while filtering out tissue-damaging ultra-violate waves below about &'' nm.

The atmosphere is composed of nitrogen and o+ygen, besides, argon, carbon dio+ide and trace gases.(. ydrosphere: The ydrosphere comprises all types of water resources oceans, seas, lakes, rivers, streams, reservoir, polar icecaps, glaciers, and ground water.

"i#ature /0 of the earth1s water supply is in the oceans,"ii#!bout (0 of the water resources is locked in the polar icecaps and glaciers."iii#2nly about 0 is available as fresh surface water-rivers, lakes streams, and ground water fit to be used for humanconsumption and other uses.

&. 3ithosphere: 3ithosphere is the outer mantle of the solid earth. $t consists of minerals occurring in the earth1s crusts and thesoil e.g. minerals, organic matter, air and water.*. 4iosphere: 4iosphere indicates the realm of living organisms and their interactions with environment, vi5 atmosphere, hydrosphere and lithosphere.

Importance:

!t present a great number of environment issues, have grown in si5e and comple+ity day by day, threatening the survival of mankind on earth. 6e study about these issues besides and effective suggestions in the Environment 7tudies. Environmentstudies have become significant for the following reasons:. Environment Issues Being of International Importance$t has been well recogni5ed that environment issues like global warming and o5one depletion, acid rain, marine pollution and

biodiversity are not merely national issues but are global issues and hence must be tackled with international efforts andcooperation.(. Problems Cropped in the Wake of Development 8evelopment, in its wake gave birth to Urbani5ation, $ndustrial 9rowth, Transportation 7ystems, !griculture and ousingetc. owever, it has become phased out in the developed world. The orth, to cleanse their own environment has, fact fully,managed to move dirty1 factories of 7outh. 6hen the 6est developed, it did so perhaps in ignorance of the environmentalimpact of its activities. Evidently such a path is neither practicable nor desirable, even if developing world follows that.&. Explosively Increase in Pollution6orld census reflects that one in every seven persons in this planted lives in $ndia. Evidently with ; per cent of the world


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&. !gricultural 9rowthThe people must be ac?uainted with the methods to sustain and increase agricultural growth with damaging the environment.igh yielding varities have caused soil salinity and damage to physical structure of soil.*. eed to 9round water $t is essential of rationali5ing the use of groundwater. Aactors like community wastes, industrial effluents and chemicalfertili5ers and pesticides have polluted our surface water and affected ?uality of the groundwater. $t is essential to restore thewater ?uality of our rivers and other water bodies as lakes are an important challenge. $t so finding our suitable strategies for consecration of water, provision of safe drinking water and keeping water bodies clean which are difficult challenges is

essential.). 8evelopment and AorestsAorests serve catchments for the rivers. 6ith increasing demand of water, plan to harness the mighty river through largeirrigation pro%ects were made. Certainly, these would submerge forestsB displace local people, damage flora and fauna. !ssuch, the dams on the river armada, 4hagirathi and elsewhere have become areas of political and scientific debate.Aorests in $ndia have been shrinking for several centuries owing to pressures of agriculture and other uses. ast areas, thatwere once green, stand today as wastelands. These areas are to be brought back under vegetative cover. The tribalcommunities inhabiting forests, respects the trees, birds and animal, which gives them sustenance. 6e must recogni5e therole of these people in restoring and conserving forests. The modern knowledge and skills of the forest department should beintegrated with the traditional knowledge and e+perience of the local communities. The strategies for the %oint managementof forests should be evolved in a well planned way.;. 8egradation of 3and!t present out of the total &(mha of land, only (;;mha possess any potential for production. 2f this, *&mha is agriculturalland nearly and D)mha suffer from varying degrees of soil degradation. 2f the remaining (&mha, *' are completely

unproductive. The remaining D&mha is classified as forest land, of which over half is denuded to various degrees. early *';million head of livestock have to be supported on &mha, or less than * per cent of the land classified as pasture land, most of which is overgra5ed. Thus, out of ((;mha, about /)mha or ;; per cent is degraded to varying degrees. 6ater and winderosion causes further degradation of almost )'mha This degradation is to be avoided./. eorientation of $nstitutionsThe people should be roused to orient institutions, attitudes and infrastructures, to suit conditions and needs today. Thechange has to be brought in keeping in view $ndia1s traditions for resources use managements and education etc. Changeshould be brought in education, in attitudes, in administrative procedures and in institutions. 4ecause it affects way peopleview technology resources and development.D. eduction of 9enetic 8iversity@roper measures to conserve genetic diversity need to be taken. !t present most wild genetic stocks have been disappearingfrom nature. 6ilding including the !siatic 3ion are facing problem of loss of genetic diversity. The protected areas network like sanctuaries, national parks, biosphere reserves are isolating populations. 7o, they are decreasing changes of one group

breeding with another. emedial steps are to be taken to check decreasing genetic diversity.. Evil Conse?uences of Urbani5ation early (/ per cent $ndians live in urban areas. Urbani5ation and industriali5ation has given birth to a great number of environmental problems that need urgent attention. 2ver &' percent of urban $ndians live in slums. 2ut of $ndia1s &,(*)towns and cities, only ( have partial or full sewerage and treatment facilities. ence, coping with rapid urbani5ation is ama%or challenge.'. !ir and water @opulationFa%ority of our industrial plants are using outdated and population technologies and makeshift facilities devoid of any provision of treating their wastes. ! great number of cities and industrial areas have been identified as the worst in terms of air and water pollution. !cts are enforced in the country, but their implement is not so easy. The reason is their implementation needs great resources, technical e+pertise, political and social will.!gain the people are to be made aware of these rules. Their support is indispensable to implement these rules.

E!o$%$tem:!n ecosystem is a natural unit consisting of all plants, animals and micro-organisms " biotic factors# in an area functioningtogether with all of the non-living physical "abiotic# factors of the environment.The ecosystem concept is the idea that living organisms are continually engaged in a highly interrelated set of relationshipswith every other element constituting the environment in which they e+ist. Eugene 2dum, one of the founders of the scienceof ecology, stated: G!ny unit that includes all of the organisms "ie: the GcommunityG# in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles"i.e.: e+change of materials between living and nonliving parts# within the system is an ecosystem.Components of an Ecosystem

We can clarify the parts of an ecosystem by listing them under the headings "abiotic" and "biotic". Processes of Ecosystems:

This figure with the plants, 5ebra, lion, and so forth illustrates the two main ideas about how ecosystems function:ecosystems have energy flows and ecosystems cycle materials. These two processes are linked, but they are not ?uite thesame "see Aigure#.

http://en.wikipedia.org/wiki/Ecosystemhttp://en.wikipedia.org/wiki/Biotic_componenthttp://en.wikipedia.org/wiki/Abiotichttp://en.wikipedia.org/wiki/Living_organismhttp://en.wikipedia.org/wiki/Environment_(biophysical)http://en.wikipedia.org/wiki/Eugene_Odumhttp://en.wikipedia.org/wiki/Ecosystemhttp://en.wikipedia.org/wiki/Biotic_componenthttp://en.wikipedia.org/wiki/Abiotichttp://en.wikipedia.org/wiki/Living_organismhttp://en.wikipedia.org/wiki/Environment_(biophysical)http://en.wikipedia.org/wiki/Eugene_Odum


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ABIOTIC COMPONENTS BIOTIC COMPONENTS

Sunlight Primary producers

Temperature Herbivores

Precipitation Carnivores

Water or moisture Omnivores

Soil or water chemistry e.g.! P!H#$%

&etritivores

etc. etc. All of these vary over space/time

Energy flo#s and material cycles$Energy enters the biological system as light energy, or photons, is transformed into chemical energy in organic molecules bycellular processes including photosynthesis and respiration, and ultimately is converted to heat energy. This energy isdissipated, meaning it is lost to the system as heatB once it is lost it cannot be recycled. 6ithout the continued input of solar energy, biological systems would ?uickly shut down. Thus the earth is an open system with respect to energy.Elements such as carbon, nitrogen, or phosphorus enter living organisms in a variety of ways. @lants obtain elements from thesurrounding atmosphere, water, or soils. !nimals may also obtain elements directly from the physical environment, butusually they obtain these mainly as a conse?uence of consuming other organisms. These materials are transformed biochemically within the bodies of organisms, but sooner or later, due to e+cretion or decomposition, they are returned to aninorganic state. 2ften bacteria complete this process, through the process called decomposition or minerali5ation.8uring decomposition these materials are not destroyed or lost, so the earth is a closed system with respect to elements "withthe e+ception of a meteorite entering the system now and then#. The elements are cycled endlessly between their biotic andabiotic states within ecosystems. Those elements whose supply tends to limit biological activity are called nutrients.

Stru!ture o& #n E!o$%$tem:4y !rchitecture or 7tructure of an Ecosystem, we mean The composition of biological community including species, numbers, biomass, life history and distribution in

space, etc.

The ?uantity and distribution of non living materials like nutrients, water etc.

The conditions of e+istence such as temperature, light etc.

!n ecosystem possesses both living components and biotic factors and nonliving or abiotic factors.The nonliving factors, called abiotic factors, are physical and chemical characteristics of the environment. They include solar energy "amount of sun light#, o+ygen, C2(, water, temperature, humidity, ph, and availability of nitrogen.The living components of the environment are called 4iotic Aactors. They include all the 3iving Things that affect anorganism. 4iotic Components are often categori5ed as @roducers, Consumers, and 8ecomposer.

Fun!tion o& #n E!o$%$tem:The function of an ecosystem is a broad, vast and often confused topic. The function of an ecosystem can be best

studied by understanding the history of ecological studies. The function of an ecosystem can be studied under the three heads.. Trophic 3evel $nteraction(. Ecological 7uccession

&. 4iogeochemistryTrophic Level Interaction deals with how the members of an ecosystem are connected based on nutritional needs. Ecological7uccession deals with the changes in featuresHmembers of an ecosystem over a period of time. 4iogeochemistry is focussedupon the cycling of essential materials in an ecosystem.

!s we would be discussing about ecological succession and bio geo chemistry in the future chapters, we shallconfine to Trophic level interaction alone in this chapter. Aor e+amination purposes, the student may also stop withe+plaining the constituents of trophic level interaction.Trophic 3evel $nteraction was developed by 5oologist Charles Elton. $t deals with who eats who and is eaten by whom in anecosystem. The study of trophic level interaction in an ecosystem gives us an idea about the energy flow through theecosystem.The trophic level interaction involves three concepts namely. Aood Chain(. Aood 6eb

&. Ecological @yramids

Ecological succession, a fundamental concept in ecology, refers to more or less predictable and orderly changes in thecomposition or structure of an ecological community. 7uccession may be initiated either by formation of new, unoccupiedhabitat "e$g$, a lava flow or a severe landslide# or by some form of disturbance "e$g$ fire, severe wind throw, logging# of an

http://en.wikipedia.org/wiki/Ecologyhttp://en.wikipedia.org/wiki/Community_(ecology)http://en.wikipedia.org/wiki/Lava_flowhttp://en.wikipedia.org/wiki/Landslidehttp://en.wikipedia.org/wiki/Disturbancehttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Windthrowhttp://en.wikipedia.org/wiki/Logginghttp://en.wikipedia.org/wiki/Ecologyhttp://en.wikipedia.org/wiki/Community_(ecology)http://en.wikipedia.org/wiki/Lava_flowhttp://en.wikipedia.org/wiki/Landslidehttp://en.wikipedia.org/wiki/Disturbancehttp://en.wikipedia.org/wiki/Firehttp://en.wikipedia.org/wiki/Windthrowhttp://en.wikipedia.org/wiki/Logging


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e+isting community. 7uccession that begins in areas where no soil is initially present is called primary succession, whereassuccession that begins in areas where soil is already present is called secondary succession.$f the development begins on an area that has not been previously occupied by a community, such as a newly e+posed rock or sand surface, a lava flow, glacial tills, or a newly formed lake, the process is known as primary succession.$f the community development is proceeding in an area from which a community was removed it is called secondarysuccession. 7econdary succession arises on sites where the vegetation cover has been disturbed by humans or animals "anabandoned crop field or cut-over forest, or natural forces such as water, wind storms, and floods.# 7econdary succession isusually more rapid as the coloni5ing area is rich in leftover soil, organic matter and seeds of the previous vegetation. $n case

of primary succession everything has to develop a new community.

iogeochemistry is the scientific discipline that involves the study of the chemical, physical, geological, and biological processes and reactions that govern the composition of the natural environment "including the biosphere, the hydrosphere, the pedosphere, the atmosphere, and the lithosphere#. $n particular, biogeochemistry is the study of the cycles of chemicalelements, such as carbon and nitrogen, and their interactions with and incorporation into living things transported throughearth scale biological systems in space through time. The field focuses on chemical cycles which are either driven by or havean impact on biological activity. @articular emphasis is placed on the study of carbon, nitrogen, sulfur, and phosphoruscycles.

Produ!er$, Con$umer$ #nd De!om'o$er$:• @roducers "autotrophs# are typically plants or algae. @lants and algae do not usually eat other organisms, but pull

nutrients from the soil or the ocean and manufacture their own food using photosynthesis. Aor this reason, they arecalled primary producers. $n this way, it is energy from the sun that usually powers the base of the food chain. IJ !ne+ception occurs in deep-sea hydrothermal ecosystems, where there is no sunlight. ere primary producersmanufacture food through a process called chemosynthesis.I(J

• Consumers "heterotrophs# cannot manufacture their own food, and need to consume other organisms. They are

usually animals. !nimal that eat primary producers, such as plants, are called herbivores. !nimals which eat other animals are called carnivores, and animals which eat both plant and other animals are called omnivores.

• 8ecomposers "detritivores# break down dead plant and animal material and wastes and release it again as energy and

nutrients into the ecosystem for recycling. 8ecomposers, such as bacteria and fungi "mushrooms#, feed on waste anddead matter, converting it into inorganic chemicals that can be recycled as mineral nutrients for plants to use again.

Ener(% Fo":$n ecology, energy flow "calorific flow# refers to the flow of energy through a food chain.$n an ecosystem, ecologists seek to ?uantify the relative importance of different component species and feeding relationships.! general energy flow scenario follows:

• 7olar energy is fi+ed by the photoautotrophs, the so called primary producers, like green plants. They absorb most

of the stored energy in the plant through digestion, and transform it into the form of energy they need, adenosinetriphosphate, through respiration. ! part of the energy received by the herbivore is converted to bodily heat "aneffect of respiration#, which is radiated away and lost from the system. Energy loss also occurs in the e+pulsion of egesta, which contains undigested energy compounds.

• 7econdary Consumers then consume the primary consumers. Energy that had been used by the primary consumers

for growth and storage is thus absorbed into the secondary consumers through the process of digestion. !s with primary consumers, secondary consumers convert this energy into a more suitable form "!T@# during respiration.!gain some energy is lost from the system, since energy which the primary consumers had used for respirationcannot be utili5ed by the secondary consumers.

• Tertiary consumers then consume the secondary consumers, and most of the energy is passed along, while some is

again lost in the ways described above and below.

•

! final link in the food chain is decomposers which break down the organic matter of the tertiary consumers "or whichever consumer is at the top of the chain# and release nutrients into the soil. 7aprotrophic bacteria and fungi aredecomposers, and play a pivotal role in the nitrogen and carbon cycles.

E!oo(i!# P%r#mid$:The main characteristic of each type of Ecosystem in trophic structure, i.e. the interaction of food chain and the si5emetabolism relationship between the linearly arranged various biotic components of an ecosystem. 6e can show the trophicstructure and function at successive trophic levels, as under:-

@roducers K erbivores K Carnivores

http://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Primary_successionhttp://en.wikipedia.org/wiki/Secondary_successionhttp://en.wikipedia.org/wiki/Chemistryhttp://en.wikipedia.org/wiki/Physicshttp://en.wikipedia.org/wiki/Geologyhttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Biospherehttp://en.wikipedia.org/wiki/Hydrospherehttp://en.wikipedia.org/wiki/Pedospherehttp://en.wikipedia.org/wiki/Earth's_atmospherehttp://en.wikipedia.org/wiki/Lithospherehttp://en.wikipedia.org/wiki/Biogeochemical_cyclehttp://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Carbonhttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Lifehttp://en.wikipedia.org/wiki/Carbon_cyclehttp://en.wikipedia.org/wiki/Nitrogen_cyclehttp://en.wikipedia.org/wiki/Sulfur_cyclehttp://en.wikipedia.org/wiki/Phosphorous_cyclehttp://en.wikipedia.org/wiki/Autotrophhttp://en.wikipedia.org/wiki/Planthttp://en.wikipedia.org/wiki/Algaehttp://en.wikipedia.org/wiki/Photosynthesishttp://en.wikipedia.org/wiki/Primary_producerhttp://en.wikipedia.org/wiki/Trophic_level#cite_note-0http://en.wikipedia.org/wiki/Trophic_level#cite_note-0http://en.wikipedia.org/wiki/Hydrothermal_ventshttp://en.wikipedia.org/wiki/Chemosynthesishttp://en.wikipedia.org/wiki/Trophic_level#cite_note-1http://en.wikipedia.org/wiki/Consumers_(food_chain)http://en.wikipedia.org/wiki/Heterotrophhttp://en.wikipedia.org/wiki/Animalhttp://en.wikipedia.org/wiki/Herbivorehttp://en.wikipedia.org/wiki/Carnivorehttp://en.wikipedia.org/wiki/Omnivorehttp://en.wikipedia.org/wiki/Decomposerhttp://en.wikipedia.org/wiki/Detritivoreshttp://en.wikipedia.org/wiki/Ecologyhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Food_chainhttp://en.wikipedia.org/wiki/Ecosystemhttp://en.wikipedia.org/wiki/Quantificationhttp://en.wikipedia.org/wiki/Specieshttp://en.wikipedia.org/wiki/Photoautotrophhttp://en.wikipedia.org/wiki/Plantshttp://en.wikipedia.org/wiki/Digestionhttp://en.wikipedia.org/wiki/Decomposerhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Primary_successionhttp://en.wikipedia.org/wiki/Secondary_successionhttp://en.wikipedia.org/wiki/Chemistryhttp://en.wikipedia.org/wiki/Physicshttp://en.wikipedia.org/wiki/Geologyhttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Biospherehttp://en.wikipedia.org/wiki/Hydrospherehttp://en.wikipedia.org/wiki/Pedospherehttp://en.wikipedia.org/wiki/Earth's_atmospherehttp://en.wikipedia.org/wiki/Lithospherehttp://en.wikipedia.org/wiki/Biogeochemical_cyclehttp://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Carbonhttp://en.wikipedia.org/wiki/Nitrogenhttp://en.wikipedia.org/wiki/Lifehttp://en.wikipedia.org/wiki/Carbon_cyclehttp://en.wikipedia.org/wiki/Nitrogen_cyclehttp://en.wikipedia.org/wiki/Sulfur_cyclehttp://en.wikipedia.org/wiki/Phosphorous_cyclehttp://en.wikipedia.org/wiki/Autotrophhttp://en.wikipedia.org/wiki/Planthttp://en.wikipedia.org/wiki/Algaehttp://en.wikipedia.org/wiki/Photosynthesishttp://en.wikipedia.org/wiki/Primary_producerhttp://en.wikipedia.org/wiki/Trophic_level#cite_note-0http://en.wikipedia.org/wiki/Hydrothermal_ventshttp://en.wikipedia.org/wiki/Chemosynthesishttp://en.wikipedia.org/wiki/Trophic_level#cite_note-1http://en.wikipedia.org/wiki/Consumers_(food_chain)http://en.wikipedia.org/wiki/Heterotrophhttp://en.wikipedia.org/wiki/Animalhttp://en.wikipedia.org/wiki/Herbivorehttp://en.wikipedia.org/wiki/Carnivorehttp://en.wikipedia.org/wiki/Omnivorehttp://en.wikipedia.org/wiki/Decomposerhttp://en.wikipedia.org/wiki/Detritivoreshttp://en.wikipedia.org/wiki/Ecologyhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Food_chainhttp://en.wikipedia.org/wiki/Ecosystemhttp://en.wikipedia.org/wiki/Quantificationhttp://en.wikipedia.org/wiki/Specieshttp://en.wikipedia.org/wiki/Photoautotrophhttp://en.wikipedia.org/wiki/Plantshttp://en.wikipedia.org/wiki/Digestionhttp://en.wikipedia.org/wiki/Decomposer


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$t may be known by means of ecological pyramids. $n this pyramid the first or producer level constitutes the base of the pyramid. The successive levels, the three make the ape+.Ecological pyramids are of three general types as under:"i# @yramid of numbers: $t shows the number of individual organisms at each level,"ii# @yramid of energy: $t shows the rate of energy flow andHor productivity at successive trophic levels.

"iii# @yramid of energy: $t shows the rate of energy flow andHor productivity at successive trophic levels.The first two pyramids, that is the pyramid of numbers and biomass may be upright or inverted. $t depends upon the nature of the food chain in the particular ecosystemB however, the pyramids of energy are always upright.! brief description of these pyramids is as under:%$ Pyramids of numbersThe pyramids of numbers show the relationship between producers, herbivores and carnivores at successive trophic levels interms or their numbers."i# $n grassland, the producers, which are mainly grasses, are always ma+imum in number."ii# This number shows a decrease towards ape+, the reason is obvious, number than the grasses."iii# The secondary consumers, snakes and li5ards are less in number than the rabbits and mice."iv# $n the top "tertiary# consumers hawks or other birds, are least in number.$n this way the pyramid becomes upright. $n a pond ecosystem, also the pyramid is upright as under:"i# The producers, which are mainly the phyto-planktons as algae, bacteria etc. are ma+. in numberB"ii# The herbivores, which are smaller fishB rotifers etc are less in number than the producersB

"iii# The secondary consumers "carnivores#, such as small fish which eat up each other, water beetles etc. are less in number than the herbivoresB"iv# Ainally, the top "tertiary# consumers, the bigger fish are least in number.owever, the case is not so in a forest eco-system. There the pyramid of numbers is somewhat different in shape:"i# @roducer, here the producers, are mainly large-si5ed trees, they are less in number, and form the base of the pyramid."ii# The herbivores, which are the fruit-eating birds, elephants, deer etc. are more in number than the producers."iii# Thereafter there is a gradual decrease in the number of successive carnivores.$n this way the pyramid is made again upright. owever, in a parasites food chain the pyramids are inverted. This is for thereason that a single plant may support the growth of many herbivores. $n its turn, each herbivore may provide nutrition toseveral parasites, which support many hyperparasites. Conse?uently from the producer towards consumers, there is a reverse position. $n other words the number of organisms gradually shows an increase, making the pyramid inverted in shape.&$ Pyramids of biomassThe pyramids of biomass are comparatively more fundamentalismB as the reason is they instead of geometric factorB show the

?uantitative relationships of the standing crops. The pyramids of biomass in different types of ecosystem may be compared asunder:$n grassland and forest there is generally a gradual decrease in biomass of organisms at successive levels from the producersto the top carnivores. $n this way, the pyramids are upright. owever, in a pond the producers are small organisms, their biomass is least, and this value gradually shows an increase towards the ape+ of the pyramid and the pyramids are madeinverted in shape.'$ Pyramid of energyThe energy pyramid gives the best picture of overall nature of the ecosystem. ere, number and weight of organisms at anylevel depends on the rate at which food is being produced. $f we compare the pyramid of energy with the pyramids of numbers and biomass, which are pictures of the standing situations "organisms present at any moment#, the pyramid of energy is a picture of the rates of passage of food mass through the food chain. $t is always upright in shape.

Fore$t E!o$%$tem: T%'e$, C)#r#!teri$ti! Fe#ture$, Stru!ture #nd Fun!tion:

! forest is more than %ust the trees. ! single forest is a complete, functioning ecosystem that supports innumerable plant andanimal species as well as earth, water, and air subsystems. The subsystems provide the essence of life of the forest and are inthemselves a byproduct of forest systems, all of which are reciprocal and interdependent.

! forest ecosystem is a comple+ of living and non-living elements which interrelate. !n ecosystem can be small "likeyour backyard# or large "like the planet earth#. $t depends on the range of individual species or group of species beingdiscussed "e.g.: a salmon stock or a forest type#, geology "e.g.: a mountain range or watershed#, and other issues.

Types

a# Temperature Aorest EcosystemThe temperature forest ecosystem is very important on Earth. Temperate forests are in regions where the climate changes alot from summer to winter. Tropical rain forests are in regions where the climate stays constant all year long. Temperateforests are almost always made of two types of trees, deciduous and evergreen.8eciduous trees are trees tht lose their leaves in the winter. Evergreens are trees that keep them all year long, like pine trees.Aorests can either be one or the other, or a combination of both. ! fourth kind of forest is a temperate rain forest. These arefound in California, 2regon and 6ashington in the United 7tates. These forests are made of redwoods and se?uoias, thetallest trees in the world. The amount of rainfall in an area determines if a forest is present. $f there is enough rain to supporttrees, then a forest will usually develop. 2therwise, the region will become grasslands. b# The Tropical ain Aorest Ecosystem

Tropical rain forests are one of the most important areas on Earth. These special ecosystems are homes to thousands of species animals and plants. Contrary to popular belief, rain forests are not only densely packed plants, but are also full of talltrees that form a ceiling from the 7un above. This ceiling keeps small plants from growing. !reas where sunlight can reachthe surface are full of interesting plants. Structure of !orest Ecosystems

8ifferent organisms e+ist within the forest layers. These organisms interact with each other and their surrounds. Eachorganism has a role or niche in sustaining the ecosystem. 7ome provide food for other organisms, other provide shelter or control populations trough predation.

Producers

!ll the living organism intakes energy in order to survive. $n a forest ecosystem, threes and other plants get their energy from sunlight. @lants produce their own food, in the form of carbohydrates. @lants are, therefore, called the primary producers, since they produce the basic foodstuffs for other organisms within food chains and food webs. @hotosynthesis isthe chemical reaction that allows plants to produce their own food.


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Consumers!nimals cannot produce their own food. They must consume food sources for the energy they need to survive. !ll

animals, including mammals, insects, and birds are called consumers. Consumers rely on plants and other animals as a foodsource. 8etails of these animals in a forest ecosystem have been given earlier. @rimary consumes only eat plants and arereferred to as herbivores. 7econd consumers are referred to as carnivores and feed on herbivores. Tertiary consumers arecarnivores that feed on other carnivores. 2mnivores eat both plant and animal matter.

Decomposers3eaves, needless, and old branches fall to the forest floor as trees grow. Eventuality all plants and animals die. These

materials are decomposed by worms, microbes, fungi, ants, and other bugs.8ecomposers break these items down into their smallest primary elements to be used again. 8ecomposers are important andthey sustain the nutrient cycle of ecosystems.

"umans are part of (orest ecosystem) umans are consumers. 6e get food and materials from forests. 4ecause of this, weare a part of the forest ecosystem. uman consumption alters forest ecosystems. uman intervention may be necessary tosustain forest communities under the increased pressure of human use.

*r#$$#nd E!o$%$tem: T%'e$ #nd C)#r#!teri$ti! Fe#ture$2ver one ?uarter of the Earth1s surface is covered by grasslands. 9rasslands are found on every continent e+cept

!ntarctica, and they make up most of !frica and !sia. There are several types of grassland. They are distinguished bydifferent names like plains, prairies, savannas and pampas.

9rasslands develop where there isn1t enough rain for forests but too much rain for deserts. 9rasslands are filled withgrass. There are many types of grass, though. Aields of wheat are considered grasslands, even though they are often cultivated by people. 9rass is special because it grows underneath the ground. 8uring cold periods the grass can stay dormant until it

warms up.The annual rainfall ranges between () to /) cm and is usually seasonalB while temperatures are moderate. 7ummer

drought and winter bli55ards can be severe, with periodic fire devastation in these biomes. The dominant plant species areshort and tall grasses and other flowering plants, many of which are perennials with e+tensively developed roots. The soils of these grasslands often have a deep organic layer. Structure and !unction

The different components of a grassland ecosystem are:"!# !biotic Component

These are the nutrients present in the soil and other components present in the air. The basic elements are supplied by carbondio+ide, water, nitrogen, sulphates etc. !ll these are present in atmosphere and soil of that location.

"4# 4iotic components$n grasslands the producers are mainly grasses, herbs and shrubs. !ll these contribute to production of biomass. Commonspecies of grass are sp. Cynodon etc. !s regards the consumers the basic three types are @rimary, 7econdary and Tertiary.

@rimary consumers feed directly on grass. !ll the gra5ing animals as well as the termites and insects come under thiscategory. The secondary consumers feed on these primary consumers and include snakes, li5ards etc. The tertiary consumersfeed on secondary consumers. E+amples are eagles and vultures. Aungi, bacteria etc are the decomposers. These microorganisms consume the dead bodies and bring the nutrients back to the soil.

De$ert E!o$%$tem: T%'e$, C)#r#!teri$ti! Fe#ture$, Stru!ture #nd Fun!tion:Types and Characteristic !eature

2ne can find at least one desert on every continent e+cept Europe and !ntarctica. Each desert is different in someway, but they all have one thing in common. $n order for an area of land to be considered a desert, it must receive less than 'inches of water a year.ow come deserts get such little waterL Clouds are scarce in these regions and we all know that without clouds, there can1t be rain, snow or any other precipitation. 4ut clouds also serve another purpose M they block out some of the 7un. The desertgets mighty hot during the day because the 7un beats down on the sand. !t night, the deserts gets very cold, because there

aren1t clouds around to keep the heat from escaping to the atmosphere.There are plenty of differences between the deserts of the world. 7ome deserts are made of very fine, red sandB others consistof sand mi+ed with pebbles and rocks. The desert sand started out as rock, but years of weathering by wind and water hascreated dunes in the deserts. These sands are mostly minerals, and sometimes oil can be found hidden deep within the rocks. Structure and !unction

The different components of a desert ecosystem are"!# !biotic ComponentThe abiotic component includes the nutrients present in the soil and the aerial environment. The characteristic feature of

the abiotic component is lack of organic matter in the soil and scarcity of water."4# 4iotic Component

The various biotic components representing three functional groups are :"a# @roducer organismsThe producers are mainly shrubs or bushes, some grasses and a few trees.The most famous desert plant is the cactus. There are many species of cacti. The saguaro cactus is the tall, pole shapedcactus. The saguaro can grow up to *' feet tall. $t can hold several tons of water inside its soft tissue. 3ike all cacti, thesaguaro has a thick, wa+y layer that protects it from the 7un. 2ther succulents include the desert rose and the living rock.This strange plant looks like a spiny rock. $t1s disguise protects it from predators. The welwitschia is a weird looking plant. $thas two long leaves and a big root. This plant is actually a type of tree and it can live for thousands of years. There are manyother kinds of desert plants. 7ome of them have thorns, others have beautiful flowers and deadly poisons. Even in the worstconditions, these plants continue to thrive."b# Consumers

These include animals such as insects and reptiles. 4esides them, some rodents, birds and some mammalian vertebratesare also found.

Desert Insects and rachnidsThere are plenty of insects in the desert. 2ne of the most common and destructive pests is the locust. ! locust is a specialtype of grasshopper. They travel from place to place, eating all the vegetation they find. 3ocusts can destroy many crops in asingle day.

ot all desert insects are bad, though. The yucca moth is very important to the yucca plant, because it carries pollen from theflower to the stigma. The darkling beetle has a hard, white, wing case that reflects the 7un1s energy. This allows the bug tolook for food during the day.


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There are also several species of ants in the desert. The harvester ants gather seeds and store them for use during the dryseason. !nd the honey pot ants have a very weird habit. 7ome members of the colony eat large amounts of sugar, so muchthat their abdomens get too large for them to move. The rest of the colony feeds off this sugar.There are also arachnids in the desert. 7piders are the most notable arachnids, but scorpions also belong in this group. 7omespecies of scorpions have poison in their sharp tails. They sting heir predators and their prey with the piercing tip.

Desert *eptileseptiles are some of the most interesting creatures of the desert. eptiles can withstand the e+treme temperatures becausethey can control their body temperatures very easily. Nou can put most of the desert reptiles into one of two categoriesB

snakes and li5ards.Fany species of rattlesnakes can be found in the desert. attlesnakes have a noisy rattle they use to warn enemies to stayaway. $f the predator isn1t careful, the rattlesnake will strike, in%ecting venom with its sharp fangs. 2ther desert snakesinclude the cobra, king snake and the hognose.3i5ards make up the second category of desert reptiles. They are probably the most bi5arre looking animals in the desert.6hile some change colors and have sharp scales for defense, others change their appearance to look more threatening. 2nesuch creature is the frilled li5ard. 6hen enemies are near, the li5ard opens its mouth, unveiling a wide frill. This makes theli5ard look bigger and scarier. The shingleback has a tail with the same shape as its head. 6hen a predator bites at the tail, theshingleback turns around and bites back. There are only two venomous li5ards in the world, and one of them is the gilamonster. $t has a very painful bite.

Desert +ammalsFany desert mammals are burrowers. They dig holes in the ground and stay there during the hot days. They return to thesurface at night to feed. amsters, rats and their relatives are all burrowers. ot only do the burrows keep the animals cool,they are also a great place to store food. 2f course, not all animals live in holes in the ground. The kangaroo and spicy

anteater both live in the !ustralian desert region. 7piny anteaters are unusual mammals because they lay eggs. The desert isalso full of wild horses, fo+es and %ackals, which are part of the canine family. !nd we can1t forget the cats. 3ions are foundall over the deserts of southern !frica. They get their water from the blood of their prey.Camels , -he Cars of the DesertCamels could be included in the mammal section. Camels are the cars of the desert. 6ithout them, people would have greatdifficulty crossing the hot terrain. There are two types of camels: 4actrian and dromedary. The main difference between thetwo is the number of humps. 8romedaries have one hump and bactrian have two. 4oth kinds are used by people, but only bactrians are found in the wild. Camels are great transportation because they use very little water. Camels can withstand veryhigh temperatures without sweating. They also store fat in their humps for food. $f a 4actrian camel travels a long distancewithout eating, its hump will actually get smaller."c# 8ecomposers8ue to poor vegetation the amount of dead organic matter is very less. !s a result the decomposers are very few. Thecommon decomposers are some bacteria and fungi, most of which are thermophillic.

A+u#ti! E!o$%$tem: T%'e$, C)#r#!teri$ti! Fe#ture$, Stru!ture #nd Fun!tion: La"es

! lake is a body of water completely surrounded by land. 3akes can either be salty or fresh water. Fost lakes are in placeswhere glaciers used to e+ist. 6hen a glacier moves forward, it carves away a deep valley and when the ice melts it forms alake in the valley. 2ther lakes are formed in craters or when a river changes its course. 3akes are short-lived surface features because the water can sink into the ground or evaporate into the sky. $n order for a like to remain, it must be constantly fed bya river or rainfall. #ivers and Streams

ivers are very important to Earth because they are ma%or forces that shape the landscape. !lso, they provide transportationand water for drinking washing and farming. ivers can flow on land or underground in deserts and seas. ivers may comefrom mountain springs, melting glaciers or lakes. ! river1s contribution to the cycle is that it collects water from the groundand returns it to the ocean. The water w drink is about & billion years old because it has been recycled over and over since the

first rainfall. ! delta is where a river meets the sea. Usually the river flows more slowly at the delta than at its start because itdeposits sediment. 7ediment can be anything from mud, sand and every rock fragments. ! special environment is createdwhen the fresh water from the river mi+es with the salty ocean water. This environment is called estuary. The longest river isthe ile iver in !frica, and the !ma5on iver in 7outh !merica carries the most water. The muddiest river is the Nellowiver in China. Estuaries

!n estuary is a uni?ue environment where fresh water and salt water come together. Estuaries are found on the coast where ariver or bay or other sources of fresh water has access to the open sea. ! good e+ample of an estuary is a salt marsh that can be found close to the coast. !nother e+ample is when a river feeds directly into the ocean. The largest estuary in the United7tates is the Chesapeake bay estuary on the east coast of the U.7.Estuaries are affected by the tides. 7o, there can be changes of salinity, temperature and other physical properties in anestuarial system which means the organisms there must be very tolerant to change. Even with that consideration, estuaries areamong the most fertile places in the world. !ll kinds of plants and animals live there. 6hen looking at estuaries, scientists?uickly reali5ed that these areas were e+tremely nutrient-rich because of sediment deposit of rivers, creeks or streams feedinginto the salt water environment. Unfortunately, estuaries haven1t always been seen as valuable. $n the past, they were seen asworthless and were used as dumps, or places for new land development "by filling in the marshy area#. owever, now thesystems are being set up to establish, manage and maintain estuary reserves, and to provide for their long-term stewardship. Pond Ecosystem

The definition of a pond is any body of water over m s?uare that is inundated, =wet> for more than D months of the year.That definition tells us ?uite a lot about a ponds ecosystem. The first is obvious, it doesn1t have to be large to be useful, infact even a bird bath will be visited by the water boatman if he is in need of a place to rest and eat. $f a pond does dry out itisn1t a disaster, both plants and animals have adapted to this eventuality. The pond is the most valuable as far as wildlife isconcerned, if the pond is reasonably shallow "no more than ' cm# and very well planted it will support a vast array of animals and plants. 7ome potential inhabitants and visitors are frogs, ewts, Toads, Ao+es, edgehogs, 4adgers birds, 4ats,9rass snakes, 7low worms, 6ater oles, 4irds of all si5es, 9reat diving beetles, 6ater boatman, 8ragon fly 3arvae andadults, 8amsel flys, 8aphnia, Cyclops, 7piders, 6ater scorpion "not dangerous#, 5oo plankton, 6irlygig beetle, @ond skaters,3ace wings. The potential list of insects and other small things is huge.

Introdu!tion to Biodiver$it%:4iodiversity is the vast array of all the species of plants, animals, insects and the microorganisms inhabiting the earth either in the a?uatic or the terrestrial habitats. The human civili5ation depends directly or indirectly upon this biodiversity for their


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very basic needs of survivalMfood, fodder, fuel, fertili5er, timber, li?uor, rubber, leather, medicines and several raw materials.This diversity1s the condition for the long-term sustainability of the environment, continuity of life on earth and themaintenance of its integrity. !lthough our understanding of the earth1s organismsMits biological resources- is still imperfect,there is no doubt that the abundance and diversity of living organisms provide many benefits and make our world a beautifuland interesting place to live. 4iodiversity is generally described in terms of its & fundamental and hierarchically related levelsof biological organisms. These are,$enetic diversity

$t includes the genetic variations within species, both among geographically separated populations and among individuals

within single population. Species diversity$t includes full range of species from micro organisms to giants and mammoth varieties of plants and animals, e.g. singlecelled viruses and bacteria etc. and multi-cellular plants, animals and fungi. Ecosystems diversity

$t studies variation in the biological communities in which species Oive, e+ist and interact.

Bio(eo(r#')i! C#$$i&i!#tion o& Indi#:$ndia has been classified into ten bio geographic 5ones by the 6ildlife $nstitute of $ndia under the 9overnment1s 4io-geographic @ro%ect Table.

T)e V#ue o& Biodiver$it%:Ecosystems and species provide an enormous range of goods and other services -immediate as well as long term, material aswell as spiritual and psychological - which are vital to our well being. The values of the earth1s biological resources can broadly be classified into- Direct .alues

Consumptive and productive uses

• Aood esources: 9rains, vegetables, fruits, nuts, condiments, tea-coffee, tobacco, li?uor, oil from plant resourcesB and

meat, fish, egg, milk "and milk products#, honey, etc. from animal resources.

• 2ther esources: Fedicine, fuel, timber, household accessories, fodder, fiber, fertili5er, wool, leather, paint, resin,

wa+, thatch. 2rnamental plants, rubber, creams, silk, feathers, decorative items, etc. Indirect .alues

on-consumptive uses and options for the future. Carbon fi+ing through photosynthesis, which provides the support system for species.(. @ollination, gene flow, etc.&. Faintaining water cycles, recharging ground water, protecting watersheds.

*. 4uffering from climatic e+treme conditions such as flood and droughtB). 7oil production and protection from erosionB;. Faintaining essential nutrient cycles, e.g. carbon, nitrogen, and o+ygen and others./. !bsorbing and decomposing pollutants, organic wastes, pesticides, air and water pollutantsBD. egulating climate at both macro and micro levelsB. @reserving aesthetic, social, scientific, educational, ethical and historical values of natural environments."i# Consumptive %se: Fan is mostly dependent on plant and animal resources for his1 dietary re?uirements. ! ma%or share of our food comes from domesticated crops and animals. 7till we derive ma%or of food from wild species. ! large section of human population is dependent on food, which we gather from seas and oceans that is harvested from free roaming wildorganisms. 7eafood is rich in minerals and vitamins and contains up to ;' percent of the protein. Unfortunately, deforestation,hunting and clearing of forests, gra5ing and e+pansion of agricultural lands removes potentially valuable food species and thewild ancestors of our domestic crops."ii# Productive %se: Trade and commerce industry is very largely dependent on forests.

4esides, timber, firewood, paper pulp, and other wood products, we get many valuable commercial products from forests.erbs of medicinal value, attan cane, sisal, rubber, pectins, resins, gums, tannins, vegetable oils, wa+es, and essential oilsare among the products gathered in the wild form forest areas. 3ike imalayan forests serve as a storehouse of medicinalherbs, which are presently being used to cure many diseases. Fany wild species e.g. milkweeds, etc. are also beinginvestigated as a source of rubber, alkaloids, and other valuable organic chemicals."iii# &edicine: Fany medicinal and aromatic plants are being e+ploited in the wild to tap their potential for different ailmentcure in the field of drug e+traction e.g. ippophae rhamnoides, Ephedra Perardiana. 8actylorrahi5a hatageria etc. 4esides,they are being cultured in plantations and protected in wild to encourage in-situ and e+-situ conservation vi5. alley of flowers, ohtang in Pullu, 3ahu Q 7piti alley. !nimal products are also sources of drugs, analgesics pharmaceuticals,antibiotics, heart regulators, anticancer and ant parasite drugs, blood pressure regulators, anticoagulants, en5ymes, andhormones."iv# Ecological enefits: Fan cannot have control over nature in the wild. $t can only put =pressure on resources and polluteenvironment. Then what makes environment act as a self-replenishing system with respect to resource generation and self-

cleanliness. To answer this comes into picture the role of biological communities.The processes of soil formation, waste disposal, air and water purification, nutrient cycling, solar energy absorption, andmanagement of biogeochemical and are all beyond the scope of man1s control. on-domestic plants, animals, and microbesdo this favor to mankind by maintaining ecological processes at no cost. These also serve as a library of gene pool. 6ildspecies of plants and animals e+ercise control over disease-carrying organisms and in suppressing pests. Aood chain e+plains


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how nature keep a control over population of organisms wherein organisms of small si5e and larger in number are consumed by organisms large in si5e and smaller in number to ne+t higher tropic level. ence, preservation of natural areas andconservation of wild species should be encouraged and practiced to restore the biological wealth."v# 'esthetic %se: 6ild species of plants and animals have always appealed man1s psyche. uman society has evolved fromhis early habitat in the forests, which abounds in flora and fauna. Till date his instinct to observe nature in the wild calls himfrom socially and culturally an evolved society, as tourist from far and wide places. Thousands of tourists visit national park,sanctuaries and forests throughout the country and especially in mountainous areas. ! glance of temperate grasslands perhapsthe most beautiful landscape pleases and comforts man. !ll domestic plants have evolved from wild ancestors and food

gathering is no longer a necessity for man but still thousands en%oy hunting, fishing and other adventurous outdoor activitiesthat involve wild species. 7uch environment and playful e+ercise gives man an opportunity to renew his pioneer skills, and beat mental ease after leading a hectic day in today1s life. Fan en%oys his surrounding by decorating it with images of wildanimals and plants."vi# Cultural enefits: ! particular species or community of organisms may have emotional value for a group of people whofeel that their identity is ine+tricably linked to the natural components of the environment that shaped their culture. This may be e+pressed as a religious value, or it may be a psychological need for access to wildlife. $n either case, we often place ahigh value on the preservation of certain wild species."vii# (ption )alues: This refers to the use of various species for the benefit of mankind, sometime in future. The hunt for various species under the scope of bio-technology is already underway for finding solutions to various environmental problems. The environmental issues being addressed to be: pollution as a ma%or problem, ways to fight various disease vi5.,cancer, diabetes etc., !$87 and others.

Biodiver$it% #t *ob#, N#tion# #nd -o!# eve$:

*+ $loal Initiatives for iodiversity 'ssessment The initiative for biodiversity assessment was taken long back in with the UE@ 4iodiversity Country 7tudies @ro%ect"consisting of bilateral and 9lobal Environmental Aacility funded studies in developing countries# implemented incooperation with donor countries and U8@. The preparation of it dates back to D/. ineteen studies have been completedand several more are in the process of completion. The approach from gene to ecosystem was initiated as a esearch !gendafor 4iodiversity, $U47H7C2@EH UE7C2, @aris "7ol brig, #. The agreed te+t of the Convention on 4iological 8iversitywas adopted by ' governments in airobi in Fay (, signed by ) governments and the European Union at the United ations Conference on Environment and 8evelopment "UCE8# held at io de Oaneiro in Oune (. !t present /*governments is party to this convention. !part from this 9lobal 4iodiversity 7trategy "(#, 9lobal biodiversityB 7tatus of the Earth1s 3iving esources "(#, Caring for the EarthB ! 7trategy for 7ustainable 3iving "#, 9lobal Farine4iological 8iversity: ! 7trategy for 4uilding Conservation into 8ecision Faking ", orwayHUE@ E+pert Conferenceon 4iodiversity " and Arom 9enes to Ecosystems: ! esearch !genda for 4iodiversity "# are the milestones on theinternational biodiversity initiatives. Fany more nations are engaged in developing their own ational 4iodiversity

7trategies. 9lobal 4iodiversity !ssessment "UE@, )# estimates the total number of animal and plant species to be between & and * million. $t further records that so far only ./) million species have been described and studied.Ecosystem diversity has not been even reasonably e+plored as yet. ence, there seems to be wide gap of knowledge atglobal, regional and local levels. Till recent past biodiversity conservation was thought to be limited to saving genes, speciesand habitats but the implementation revolutionary policies and more awareness has led to the emergence of a framework based upon saving biodiversity, studying and most importantly using it sustainable. eforms in the field of forestry,agriculture, technology, international trade agreement and watershed management is re?uired. 4iodiversity is directly or indirectly related to masses "researchers, government agencies, non-government agencies and private sectors# at all levels of development. 7ince we depend upon biodiversity our various activities can be linked to its usage and conservation.Therefore, trade, economics, population, land tenure, intellectual property rights and resource consumption Q waste are allrelated to biodiversity conservation. ence, its sustainable use can be promoted through information, ethics, knowledge andawareness.-+ Levels of 'ction

eed for biodiversity conservation is reali5ed by all nations of the world because their lies common interest of masses. Fostof the resources do not belong to an individual, a nation or a continent. They are simply global. Each and every member onthe earth has e?ual right over it. To limit the loss of biodiversity globally * ma%or steps have been reali5ed important atnational, regional and local levels."i# 9lobal Environment Aacility "9EA#6orld 4ank, United ations 8evelopment @rogramme "U8@#, United ations Environment @rogramme "UE@#established the 9EA in '' on a three-year pilot basis. The 9EA is e+pected to commit R *'' million for the biodiversityconservation issue."ii# $nternational 4iodiversity 7trategy @rogramme "$47@#6orld esources $nstitute "6$#, 6orld Conservation Union "6CU#, UE@ together with more than *' 9overnmental andnon-9overnmental organi5ations have prepared the framework to drastically reduce the loss of biodiversity. This would servemankind on a more sustainable basis."iii# Convention on 4iological 8iversity "C248#Under the aegis of UE@, more than '' nations gathered during Earth 7ummit at4ra5il. This was accomplished to work out a legal framework for governing international financial support for biodiversityconservation, "iv# !genda ($t is developed through a series of inter-9overnmental preparatory meetings with input from a variety of non-9overnmental processes including the 4iodiversity 7trategy @rogramme. !9E8! ( provides a plan of action on a number of issuesincluding biodiversity.

Indi# #$ # Me(#Diver$it% N#tion:3ying at the %unction of !gro-tropical, Euro-!sian and the $ndo-Falayan biogeography realms, $ndia is a country of vast biodiversity in the world and ?uite a significant one all over the globe. $n fact, it is among the twelve =Fega diversity>countries in the world. $ndia is also a =avilov> centre of high crop genetic diversityMso named after the ussian agro botanist .$. avilov who identified about eight such centers around the world in the )'s. $ndia, a mega-biodiversitycountry, while following the path of development, has been sensitive to the needs of conservation. $ndia1s strategies for

conservation and sustainable utili5ation of biodiversity in the past aimed at providing special status and protection to biodiversity rich areas by declaring them as national parks. 6ildlife sanctuaries, biosphere reserves, ecologically fragile andsensitive areas has helped in reducing pressure from reserve forests by alternative measures of fuel wood and fodder needsatisfaction by a forestation of degraded areas and wastelands, creation of e+-suit conservation facilities such as gene banks


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and eco-development. The challenges before $ndia are not only to sustain the efforts of the past but also further add to theseefforts by involving people in the mission.

.ot$'ot$ o& Biodiver$it%:!reas with rich biodiversity and e+hibiting high levels of endemism, which are under immediate threat of species e+tinctionand habitat destruction, are recogni5ed on priority basis worldwide for conservation practices and are known as hot spots. (hot spots identified world over represent *0 of world1s plant species in only '.(0 of its total land surface. Twelve megadiversity nations "Fe+ico, Columbia, 4ra5il, @eru, Ecuador, Fadagascar, $ndonesia, Falaysia, $ndia, China and !ustralia#,

contain ;'-/' 0 of the world1s biodiversity. 2ut of the total hot spots worldwide two lies in $ndia. These are represented by orth-eastern imalayas "Phasi %aintia hills and the lower imalayan slopes embracing areas of !runachal @radesh, !ssam,Feghalaya, agaland and Tripura# and 6estern 9hats region in the south. These fall under heavy rainfall 5ones. The rainforests of the 6estern 9hats and the eastern imalayas consist of very dense and lofty trees with a multitude of speciesoccurring in the same area. undreds of species of trees can be identified in a hectare of land besides mosses, ferns,epiphytes, orchids, lianas and vines, herbs shrubs and fungi that make up this region the most diverse habitat. 9iant treesstretch up towards the sun. 4uttress roots, anchored within the soil, support the smooth straight trunks, which rise &' mts. or more before branching out. The spreading crowns effectively block out most of the light from the light from the ground beneath.%$ North/east "imalayasArom the dense evergreen and semi-evergreen vegetation of the foothills in the Eastern imalaya, the character of vegetationchanges at altitudes of )() m to D&' m. Saks, magnolias, laurels and birches covered with moss and ferns replace the sal,silk-cotton trees and giant bamboos of the foothills. !t about (/*) m to &;;' m one enters the coniferous forest of pine, fir yew and %unipers. There is undergrowth of scrubby hododendrons and dwarfs bamboos. 8ue to high humidity and much

higher rainfall, lichens, mosses, orchids and other epiphytes cover the tree trunks. The animal life in the temperate region isdifferent from the western imalaya and is characteri5ed by the presence of $ndo Chinese fauna. The red panda, hog badgers,ferret badgers, crestless porcupines are typical species of this area. Three kinds of goat antelopes also occur in the easternimalaya and are relatives of the European chamois. 9oral is a smaller goat antelope found throughout the tract on ruggedgrassy slopes and on rocky grounds near the conifers forests.&$ Western 0hatsThe 6estern 9hats and the central belt lying to the west of it, is a region of very high rainfall and is characteri5ed byevergreen vegetation, its flora and fauna, being a kin to the evergreen rain forest of north-eastern $ndia. !mong the maca?uesthe lion tailed "Facaca silenus# is one of the world1s most endangered primates, surviving in the evergreen forests of the6estern 9hats of south $ndiaB its total population is estimated to be about D'' only.$n the langur group, the nilgiri $angur1 "@resbvtis %ohni# is a multi habitat species occurring in addition to the shoals, in thetemperate evergreen forests above /'' m altitude in the 6estern 9hats. ! number of climbing animals have evolved glidingmechanisms and are particularly characteristic of these forests. !mong these are the flying s?uirrels. The other characteristic

species of the 6estern 9hats are the ilgiri mongoose, the strip necked mongoose, the malabar civet and the spiny mouse.The flora and fauna of these evergreen regions have not been fully e+plored. 4eing a store house of a large variety of plantsand animals, these forests represent one of the richest gene pool resources of flora and fauna in the country. Though a largenumber of such forests have not been destroyed for various plantation crops like rubber, cocoa, coffee etc., whatever virginforests remain have to be specially protected as in the 7ilent alley of Perala or the rich orchid belt of the north-easternimalayas in !runachal @radesh and 7ikkim.

T)re#t$ to Biodiver$it%:The biggest reason for the current increase in e+tinctions is habitat loss. 8estruction of tropical forests, coral reefs, estuaries,Farshes and other biologically rich ecosystems threaten to eliminate thousands or even millions of species in a human-caused mass e+tinction that could rival those of geologic history. 4y destroying habitat, we eliminate not only prominentspecies but also many obscure ones of which we may not even be aware. 2ver harvesting of food species is probably themost obvious way in which humans directly destroy biological resources. There are many, historic e+amples of human

disturbances of natural systems. 2nce-fertile areas have become deserts because of unsound forestry, gra5ing and agricultural practices. Technology nm> makes it possible for us to destroy vast areas even faster than in the past. Undoubtedly the greatestcurrent losses in terms of biological diversity and uni?ue species occur when tropical moist forests are disrupted.*+ &ain Causes of Threat to Species

$t is well known now that several plant species have become e+tinct due to certain natural phenomena, such as landupheavals, volcanic eruptions, glaciations and protracted periods of rain or drought, spreading of desert lands, forest fires andeutrophication in the geological past. 6hile such natural processes in the past had no doubt led to the e+tinction of flora, theresulting new environmental conditions had also resulted in the evolution and speciation of new flora and migration of floralelements. 4ut, in recent times man with his anthropogenic associates and other factors or practices such as fire or slash and burn1 for shifting cultivation "also called as %hum1 or podu1 cultivation in $ndia#, gra5ing by cattle and by several other mechanical means, has suddenly accelerated disastrous condition in natural ecosystems. 4esides, commercial e+ploitation of entire plants, roots, rhi5omes, tubers bulbs seeds and fruits has been the prime cause of depletion of more important wildeconomic plants throughout the world for lucrative financial gains, in the trade which flourishes both by legal and illegalmeans auvolfia, serpentina, Coptis teeta, 8ioscorea sp. and @odophylum he+andrum serve as good e+amples..i/ 0aitat Destruction

8eforestation has been one of the ma%or causes for the depletion of wildlife. 6ith the increase in human population and thegrowing need for resources, forests were cleared or for agricultural operations, for human habitation and for gra5ing their livestock. Technological advance and human progress had a direct bearing on the e+ploitation of natural resources. Aoresttrees were cut to yield timber for building houses, for making furniture and for collecting wood as fuel. $ndustries made aheavy demand on forest resources such as wood for paper- making, e+ploitation of gums and resins, mining of forestland for mineral ores, building materials, etc. abitat destruction thus has an adverse impact on wildlife as it leads to the loss of anenvironment, which provides them food and breeding grounds or nesting sites to facilitate rearing of their young ones. 6ildanimals are left with no alternative but to adapt, migrate or perish. 6idespread habitat loss all over the country hasdiminished the population of many species, making them rare-and endangered. $n our race for progress and prosperity, wehave disturbed the delicate balance of ature..ii/ 0unting and Poaching

Uncontrolled hunting of wildlife for pleasure, food, furs. 7kins, horns, tusks, etc. pose a serious threat to the survival of

wildlife. $n $ndia, the Cheetah was hunted to e+tinction. The illegal trade in animal skins has been responsible for thedestruction of a large of tigers, leopards, deer, fishing cat, crocodiles and snakes, as well as birds with beautiful plumage.Elephants were hunted for ivory. The rhinoceros was killed for its horns because of the superstitious belief that it containedaphrodisiac properties. There are laws in the country to prevent such illegal trade, but unscrupulous elements, traders and


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e+porters often violate these. !dded to this is the practice of trade in e+otic mammals, birds and reptiles and use of wildanimals in biomedical research..iii/ Pollution

@ollution of air, water and soil due to various industrial activities not only affect our health, but the health and well being of animal population also. $ndustrial effluents one reaching water bodies adversely affect a?uatic life. @esticides like 88T and8ieldrin are very harmful. These have a ma%or effect particularly sea birds and their eggs. 2il pollution is another serious problem affecting the seas through leakage from cargo ships or accidents. 4esides, there are other numerous factors thataffect wildlife population, which are mostly anthropogenic. $ntroduction of e+otic species, unhealthy agricultural practices,

diseases introduced by domesticated animals, silting of rivers, floods and droughts are a few to name some. These all havesomehow contributed to the process of endangering animal species.

M#n #nd /idi&e Con&i!t:Fan by virtue of his nature is destructive and self-centred despite the fact that he is known as social animal. Until he reali5esthe need of time no rules and regulations may help. The e+ploitation of forests and wildlife or rare species for commercial purposes should be stopped. ! good tiger skin is worth more than five thousand rupees. The tusks of an elephant and the skinof big cats also fetch a good pri5e. The horns of rhinoceros carry a highly fancy pri5e. This high market value has lead tounlimited slaughter of these animals.

End#n(ered #nd Endemi! S'e!ie$ o& Indi#:The Aorest administration in $ndia is more than '' years old. Efforts to identify plant species as a part of wildlife and torecogni5e the importance for providing special protection to endangered plant species have so far been negligible. Thee+tinction of certain attractive animals stimulated efforts to protect fauna, but no special heed was given to flora. The word

6ildlife1 had till recently been considered synonymous with animal life and conse?uently, conservations and naturalistshave their attention only to conservation of animal species. $t was only in the year ;D at an $nternational Conference"UE7C2 ;D# that the problem of conservation of flora and fauna was appreciated and several recommendations weremade urging the $nternational 4iological @rogramme "$4@#, .the $nternational Union for Conservation of ature and aturalresources "$UC# and various international and national organi5ations to initiate studies in to the problems involved, particularly the problem of protecting and preserving wild fauna and flora in their natural habitatHecosystems establishingnature reserves. 3ater at the 'th 9eneral Feeting of the $UC, the 7urvival 7ervice Commission reviewed the status of endangered species of plants and their habitats. !ccording to the recent promulgations of the United 7tates Endangered7pecies !ct "/, UP 6ild Creatures and 6ild @lants !ct "$/)# and the development of international conventions onconservations "6etlands Convention# and the setting up of 4iological ecords Centre of the ature Conservancy, UP, andthreatened plants, orchids, cycads tree, created a wide awakening of the need for the conservations, preservation and protection of floras of the world. !ccording to the olume ) of ed 8ata 4ook on angiosperms started by the 7urvival7ervice Commission of the $UC in the year /' "Felville, /'#, it is estimated that out of the total of three lakes "'.&

million# species of plants in the world, over (',''' were in the category of either endangered or vulnerable and threatenedwith e+tinction by the year (''' !.8. The following categories of rare species have been recogni5ed by the $UC, mainly based on "i# present distribution, "ii# decline in number of time, "iii# abundance and ?uality of natural habitats, and "iv# biology and potential value of the species.

Endangered 1E27pecies in danger of e+tinction and whose survival is unlikely if the casual factors continue operating, included are specieswhose numbers have been reduced to a critical level or whose habitats have been so drastically reduced that they are deemedto be in immediate danger of e+tinction..ulnerable 1.27pecies believed likely to move into the endangered category in the near future if the casual factors continue operating.$ncluded are species, of which most or all the populations are decreasing because of over-e+ploitation, e+tensive destructionof habitat or other environmental, disturbance species with populations that have been seriously depleted and whose ultimate

security is not yet assuredB and species with populations that are still abundant but are under threat from serious adversefactors throughout their range. *are 1*27pecies with small world populations that are not at present endangered or vulnerable, but are at risk. These species areusually locali5ed within restricted geographical areas or habitats or thinly scattered over a more e+tensive range.-hreatened 1-2Threatened is used in the conservation conte+t for species which are in one of the categories, Endangered, ulnerable andare. 7ome species are marked as threatened where it is known that they are Endangered, ulnerable or are, but there isknown that they are Endangered, ulnerable or are, but there is not enough information to say which of these threecategories is appropriate.3ut of Danger 1327pecies formerly included in one of the above categories, but which are now considered relatively secure because effectiveconservation measures have been taken or the previous threat to their survival has been removed.

Indeterminate 1I27pecies that are suspected of belonging to one of the first three categories, but for which insufficient information is currentlyavailable1. Endemic Species of India

$ndia has a very rich element of endemics in its flora. !ccording to Chatter%ee "*'#, $ndian subcontinent has about ;.) percent to endemic flora with about /,''' endemic and &* endemic genera. 2f these the imalayas and the Phasi illsaccount for about &,''' and 8eccan peninsula for about (,''' endemic species. These figures speak elo?uently of the greatneed for protecting the endemics. This can be done effectively by carefully analy5ing the floristic composition of the various phytogeographical units of $ndian flora and by selecting suitable natural forests in these units and preserving them as4iosphere eserves1, 7apria himalayana, Uvaria $nroad, !lcimandra cathcartii Fagnolia gustavii, F pealiana, @achylarna+ pleiocarpa, epenthes khasiana, 8icentra royler several species of @rimula and hododendron and the 3ady1s7lipperorchids. @.aphiopodilum insigne, @.hirsutissimum, @.faireenum, @.spicerianum and @.venusturm, are some of thenoteworthy endemics of the imalayas and Phasi ills. !ntiaris ta+icaria, Campanual cytinoides, @edicularis perroter and the some species of the @odostemaceae are endemic to 6estern ghatsHthe ilgiri ills in 7outh $ndia.


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2. Endangered Flora and Fauna of India

7ome plants and animals have already become e+tinct and there are many facing danger of e+tinction.The basic reasons of e+tinction of wildlife are as follows:"# 8estruction of their natural habitats due to e+panding agriculture, urbani5ation and industriali5ation."(# 2vergra5ing by domestic animals that convert the area into deserts." @oaching for meat, skin, fur, ivory, rhino horns etc."*# E+port of some species.The 4otanical 7urvey of $ndia "47$# could so far complete survey of plant resources in only about &H)th of the country. !s

per the targets set, 47$ should have complete survey of the remaining (H)th of the country by D. $t is planned to publish ational Alora of the country in (* volumes by (''' !.8.The oological 7urvey of $ndia "7$# could so far survey only about H& of the country, and is planned to complete the surveyof the /)0 of the remaining (H&rd area of the country by (''' !.8. 7i+ty-two volumes of Aauna of $ndia are to be broughtout by ('''. 8ata regarding all endangered plant and animal species of the country are also not complete. $t was set that dataregarding all endangered plant species will be inventoried by (, for which 47$ had been restructured, has reported to publish ol. $ of ed 8ata 4ook of $ndian plants covering (&) species. ed 8ata 4ook of $ndian @lants ol. $$ containingabout ('' rare and endangered species is completed and printed "8.2. En. !nnual eport, DD-D#. The status survey of endangered animal species is being done and is claimed to be completed and ed 8ata 4ook compiled by ). !ccording tothe ed 8ata 4ook of $UC "$nternational Union for Conservation of ature and atural esources#, more than '''creatures are threatened with e+tinction, some very soon, some within a decade or so. !mong these facing most immediatedanger are, all species of rhinoceros particularly the $ndian variety the oyal 4engal, and 7iberian Tigers, the Fe+icangri55ly bear, the red wolf, the mountain gorillaB the !rabian ory+ and the !siatic lion.

Con$erv#tion o& Biodiver$it%:The hope for conservation of natural biodiversity however rests on preservation of selected ecosystems and representativeareas of different vegetation types in the country as well as on saving some of the e+tinction-prone species. The number of endangered species of plants and animals is on the rise, which has prompted government and non-governmentalorgani5ations to take certain steps in this direction. Aorestry and wildlife were primarily under the control of stategovernments but later on looking to the gravity of the situation a separate Finistry of Environment and Aorests wasestablished.The aims and ob%ectives of wildlife management in $ndia includes the following

"i# @rotection of natural habitats"ii# Faintenance of a viable number of species"iii# Establishment of biosphere reserves"iv# @rotection through legislation

7ome of the non-government organi5ations working in this direction are

"i# 4ombay atural istory 7ociety"ii# 6ildlife @reservation 7ociety of $ndia, 8ehradun."iii# 6orld 6ide Aund for ature $ndia "66A#

3aws 9overning 4iodiversity Conservation in $ndia"i# The Fadras 6ild Elephant @reservation !ct, D/&."ii# !ll $ndia Elephant @reservation !ct, D/."iii# The $ndian Aisheries !ct, D/."iv# 6ild 4irds and 6ild !nimals @rotection !ct, (."v# The $ndian Aorest !ct, (/."vi# 4engal hinoceros !ct, &(."vii# aily ational @ark !ct.. &;."viii# 4ombay 6ild, !nimals and 6ild 4irds @rotection !ct, )."i+# !ssam hinoceros @rotection !ct, )*.

"+# The Cruelty against !nimals !ct, ;'."+i# The 6ildlife "@rotection# !ct, /(."+ii# The Aorest "Conservation# !ct, D'."+iii# 6ildlife "@rotection# !mendment !ctB ."+iv# Conservation of Aorests and ational Ecosystems !ct, *.

InSitu #nd E0Situ Con$erv#tion o& Biodiver$it%:The goal of biodiversity conservation can be attained in a number of ways. The concept of gene banks regulates all thesemethods. In1situ conservation

$t can be defined as the conservation of plants and animals in their native ecosystem "natural habitats# or even manmadeecosystem, where they naturally occur. This type of conservation is applicable to wild flora and fauna as conservation isachieved through protection of populations in their natural ecosystems. The concept of protected areas falls under thiscategory e.g. ational @arks, 7anctuaries and 4iosphere reserves, etc. E21situ conservation

$t can he defined as the conservation of plants and animals away from their natural habitats, which includes collection of samples of genetic diversity and their treatment in the laboratory, where they are cultured. The concept of gene banks1 has primarily become the talk for e+-situ conservation as it is important for conservation of agricultural crops and forestry basedafforestation programmes. 9enetic resource centers fall under this category and include botanical gardens, 5oos etc.


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Unit II

ENVIRONEN!"# $O##U!ION

Introduction

@ollution may be defined as an undesirable change in the physical, chemical or biological characteristics of air, water andland that may be harmful to human life and other animals, living conditions, industrial processes and cultural assets. @ollutioncan be natural or man- made. The agents that pollute are called pollutants.

Pollutants

@ollutants are by-products of man1s action. The important pollutants are summari5ed below: 8eposited matterV7oot, smoke, tar or dust and domestic wastes. 9asesVC2, nitrogen o+ides, sulphur o+ides, halogens "chlorine, bromine and iodine#. FetalsV3ead, 5inc, iron and chromium. $ndustrial pollutantsV4en5ene, ether, acetic acid etc., and cyanide compounds. !griculture pollutantsV@esticides, herbicides, fungicides and fertili5ers. @hotochemical pollutantsV25one, o+ides of nitrogen, aldehydes, ethylene, photochemical smog and pro+y acetyl nitrate. adiation pollutantsVadioactive substances and radioactive fall-outs of the nuclear test.

Classification of Pollutants

2n the basis of natural disposal, pollutants are of two types:"i# on-degradable pollutantsThese are the pollutants, which degrade at a very slow pace by the natural biological processes. These are inorganiccompounds such as salts "chlorides#, metallic o+ides waste producing materials and materials like, aluminium cans, mercuric

salts and even 88T. These continue to accumulate in the environment."ii# 4iodegradable pollutantsThese include domestic sewage that easily decomposes under natural processes and can be rapidly decomposed by naturalHartificial methods. These cause serious problems when accumulated in large amounts as the pace of deposition e+ceeds the pace of decomposition of disposal. 2n the basis of the form in which they persist after their release into the environment, pollutants can be categori5ed under two types:"i# @rimary pollutants: These include those substances, which are emitted directly from some identifiable sources.

"a# 7ulphur compounds: 72(, 72&, (7 produced by the o+idation of fuel."b# Carbon compounds: 2+ides of carbon "C2WC2(# and hydrocarbons."c# itrogen compounds: 2( and &."d# alogen compounds: ydrogen fluoride "A# and hydrochloric acid "Cl#."e# @articles of different si5e and substances: These are found suspended in air.

The fine particles below the diameter of ''u are more abundant and include particles of metals, carbon, tar, pollen, fungi,

bacteria, silicates and others."ii# 7econdary pollutants. The secondary pollutants are produced by the combination of primary emitted pollutants. in theatmosphere. $n bright sunlight, a photochemical reaction occurs between nitrogen o+idesB o+ygen and waste hydrocarbonsfrom gasoline that forms pero+yacetyle nitrate "@!# and o5one "2 , 4oth of them are to+ic components of smog and causesmarting eyes and lung damage."iii# 7mog. The fog deposited with smoke and chemical fumes forms a dark and thick covering, the smog. 7mog is verycommon in almost all the industrial areas as the smog is trapped for many days by the stagnant air. $t is harmful both for animals and plants.

Air Poution:The 62 defines air pollution as the presence of materials in the air in such concentration which are harmful to man and hisenvironment. ! number of ingredients find their way in the air and these are mostly gases, which rapidly spread over wideareas.

Sources of 'ir Pollution

arious sources of air pollution are fossil fuels, industries, agricultural activities, wars, natural causes arid emissions fromvehicles."i# 4urning Aossil Auels4urning of wood, charcoal and other fossil fuels cause air pollution by the release of carbon dio+ide "C2 (#, carbon, sulphur dio+ide etc. @etroleum consists mainly of C, 7 and (."ii# Emissions from !utomobilesehicles are mainly responsible for more than D'0 of total air pollution. The ma%or pollutants released from automobiles,locomotives, aircraft etc., include C2, unburnt hydrocarbons and 2+."iii# $ndustries@aper and pulpfactories, petroleum refineries, fertili5er plants, and steel industries, thermal power plants are the main sourcesof air pollution. They add various harmful gases like C2, 72 &, 2, C etc., to the atmosphere. Te+tile factories releasecotton dust into the air. Cities e+periencing this type of pollution are Panpur, 7urat and !hmedabad. The pesticide andinsecticide industries are posing serious threat to the environment. Aood processing industries and tanneries emit offensiveodors. elease of poisonous gases from accidents also poses serious threats. e.g. 4hopal 9as Tragedy in which methylisocynate "F$C# gas leakage killed several people. $n Tokyo, about &* tones of carbon particles mi+ed with other suspended particles settle per s?uare kilometer every day."iv# !gricultural !ctivities7praying of insecticides and weedicides also cause air pollution. These, when inhaled create severe problems to both animalsand man."v# 6arsarious forms of e+plosives used in war pollute the air by releasing poisonous gases. This greatly disturbs the ecology of thearea. uclear e+plosions pollute air by radioactive rays. The effects of nuclear e+plosions on iroshima and agasaki arewell-known e+amples."vi# atural Causes9as emissions from active volcanoes, marsh gas, spores of fungi and pollens

Common ir Pollutants!ir pollutants are of two main typesXgaseous and particulate, 2+ides of C, ( and 7 are gaseous pollutants. @articulate pollutants may be solid or li?uid particles, larger particles settle down ?uickly vi5., sand and water droplets whereas small


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dust particles remain suspended in air for a long time. These are added into the atmosphere by the processes of blasting,drilling, crushing, grinding and mi+ing."i# Carbon 8io+ideC2( content of air has increased by ('0 during the last century. C2( causes nausea and headache. $t1s increase in the air maycause green house effect, rise in the atmospheric temperature. This may melt the polar ice resulting in rise in level of oceansand flooding of coastal regions."ii# Carbon Fono+ide$t1s a very poisonous gas, produced by incomplete combustion of fuel, if inhaled, combines with hemoglobin, reducing its

o+ygen-carrying capacity. This leads to la5iness, reduced vision and death."iii# 2+ides of itrogenThese include 2 and 2(, which are released by automobiles and chemical industries as waste gases and also by burningof materials. These are harmful and lower the o+ygen carrying capacity of blood."iv# 2+ides of 7ulphur 72( and 72& are produced by burning of coal and petroleum and are harmful to buildings, clothing, plants and animals. ighconcentration of 72( causes chlorosis "yellowing of leaves#, plasmolysis, damage to mucous membrane and metabolicinhibition. 72( and 72& react with water to form 7ulphuric and sulphurous acids. These may precipitate as rain or snow producing acid rain or acid precipitation."v# @hotochemical 2+idantsThey are formed by the photochemical reactions between primary pollutants, vi5. o+ides of nitrogen and hydrocarbons. itrogen o+ides in the presence of sunlight react with unburnt hydrocarbons to form pero+y acetyl nitrate "@!#, 25one,aldehydes and some other comple+ organic compounds in the air."vi# ydrocarbons

These are unburnt discharges from incomplete combustion of fuel in automobiles. These form @! with nitrogen o+ides,which is highly to+ic."vii# @articulate Fatter $ndustries and automobiles release fine solid and li?uid particles into the air. Aly ash and soot from burning of coal, metaldust containing lead, chromium, nickel, cadmium, 5inc and mercury from metallurgical processesB cotton dust from te+tilemillsB and pesticides sprayed on crops are e+amples of particulate pollutants in the air. These are in%urious to respiratory tract."viii# !erosols!erosols are chemicals released in the air in vapour form. These include fluorocarbon "carbon compound having fluorine# present in emissions from the Oet aeroplanes. !erosols deplete the o5one layer. Thinning of o5one layer results in moreharmful ultraviolet rays reaching the earth, which are harmful to skin, and can lead to skin cancer also."i+# adioactive 7ubstancesThese are released by nuclear e+plosions and e+plosives. These are e+tremely harmful for health."+# Aluorides

ocks, soils and. minerals containing fluorides release an e+tremely to+ic gas called hydrogen fluoride on heating. This gas ishighly in%urious to livestock and cattle.

Pollution in India

$ndia supports a large network of factories and industries. These factories are generally locali5ed in eight or ten largeindustrial centres. These are also a great source of air as well water pollution. To be on a safer side delocalisation of industries is the need of the time. This would lead to an even distribution of pollutants and faster degeneration of pollutants.The ma%or pollutants coming out from these industries are -"i# $ndustrial @ollutants. The common air pollutants from industries are 72 (, C2, C2(, (7 and hydrocarbons together withdust, smoke and grit. These are produced by the burning of coal and petroleum and by the combustion of lignite at thermal power stations. The chemical industries release Cl, chlorine, nitrogen o+ide and o+ides of copper, 5inc, lead and arsenic.The fertili5er factories at 9orakhpur and !hmedabadB the steel industries at 4hilai, ourkela, Oamshedpur and 8urgapur pollute the air with above-said gases.

"ii# !utomobile E+hausts. !utomobiles run by petrol and diesel produce C2, nitrogen o+ides and hydrocarbons. undredsand thousands tons of hydrocarbons and C2 are emitte

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