evs multid.nature of evs

Multidisciplinary Nature of

Environmental Studies

The study which deals with the environment and it’s components is known as environmental study The world is divided into two major partsNatural world and Built world

Contains Plants , animals, air, water, soil etc.

Natural world

Built world

Contains social institute, organizations, and other things using science and

technology etc.

World

Includes plants , animals, micro-organism etc.

Biotic AbioticIncludes air, soil, water, temperature, atmosphere etc.

Environmental component

Scope and Importance of

Environmental It’s study is necessary to control pollutionOver exploitation of resourcesAcid rain, global warming ,energy crisis etc.It helps to create new jobs in the field of environment.It also helpful to demonstrate control uses of resources

Need for Public Awareness

Public awareness is necessary for controlling the environment degradation.

A Centre of Environmental Education (CEE) has been setup by the ministry of environment.

The main objective of this organization is to improve public awareness and

understanding of the environment.

Following methods are suggested for environmental awareness among the people……………Introduction of environmental education

at all stages from school to university level.

Involvement of media, radio and T.V.

Organization of training programmes of information and knowledge by expertise

Natural Resources Natural resources are components of environment.

It includes energy, minerals, soil, forest, food, water and plants.

Natural resources can be divided into two major parts

Natural Resources

Renewable resources

Non-renewable resources

Renewable Resources These are non-exhaustive.

They can be generated again and again within a given span of time.

For example solar energy, biomass energy, hydropower energy etc.

Non-renewable Resources These are exhaustive.

They can’t be generated again and again within a given span of time. It takes many years for regenerate.

For example coal, petroleum, minerals etc.

Classification of Natural Resources

Forest resourcesWater resourcesMineral resources Food resourcesEnergy resourcesLand resources

Forest ResourcesIt is a very important renewable

resources.

It is a biotic community and a valuable wealth.

1/3rd of the earth is covered by the forest

Forest UsageTrees provides oxygen by photosynthesis which is necessary for human beings.

Trees absorb CO2 which plays a major role in global warming.

It provides food, timber for surviving the life.

It also provides many important chemical which used in medicine and in industries.

It helps in preventing soil erosion It also absorb many toxic gases and help in cleaning the air.

DeforestationDestruction of forest is known as deforestation .

Forest are burned or cut down for various reasons e.g. clearing of land for agriculture, expansion of cities, and many more.

This deforestation is disastrous and irreversible.

At present we are losing forests at the rate of 1.7 crores hectares annually.

Fuel requirementShift agricultureIndustrial demandConstruction projectsGrazing landForest fireMining operations

Causes of Deforestation

Soil erosionExpansions of desertsDecrease in rainfallLose of fertile landEffect on climate

Effects of Deforestation

Loss of biodiversityLowering of water levelEconomic lossesLoss of medicinal plantsEnvironmental changes

Commercial and industrial demand could out-strip supply leading to decimation of forests particularly wood.

Major effects of timber extraction on forest and tribal people areSoil erosion specially on slopesSedimentation of irrigation system

Effects of Timber Extraction

Forest fragmentationLoss of biodiversityClimate changeLoss of animal and plant speciesExploitation of tribal people by contractorsLoss of non-timber products

Major effect of mining operations on forest and tribal peoples are

Degradation of landLoss of top soil due to deforestationWater pollution due to discharge of highly mineralized mine waterAir pollution due to greenhouse gases (CH4 )

Effects of Mining

Loss of flora and faunaFire hazardsOre transport hazard tribal people may be forced into a new way of life for which they are unpreparedMigration of tribal people from mining areas to other areas in search of land and food

Major effect of dams or river valley on forest and tribal peoples are

Degradation of catchment areasCommand area developmentDeforestation and loss of flora and fauna

Effects Dams or River Valley

Increased incidence of water borne diseases (malaria, filaria etc.)

Acute scarcity of fuel wood and other forest products for tribal people

Rehabilitation and resettlement of those affected

Himalayan region

Increasing destruction and degradation of forest contribute to heave erosion of top soilErratic rainfall and recurring floodsLoss of productivity

Case studies

North eastern states

Increasing destruction and degradation of forest decrease rainfall in these areas

Water ResourcesWater is the source of life on the

earth.Around 70% of the earth surface is covered by water mainly in the form of ocean.Less then 1% of total water is available in the form of fresh water.

Importance of water

It is essential not only human but also all life.About 60% of human body is water.Every metabolic activity within human body completed with water.Therefore it is pre-requisite for development.

Over-utilization of water

99% of earth water is unsuitable for beneficial human use.Less then 1% of total water is available in the form of fresh water.This little fresh water comes from surface water and ground water sources

Various surface water sources areNatural lakes and pondsArtificial impounding reservoirsRivers and streamsSea waterDegradation of the sources by disposal of sewage and industrial effluents without treatment are major environmental issue

Surface water source

After glaciers, ice caps and snowfield ground water is the largest fresh water reservoirIt is colorless and clear water but hard.If withdrawn method is faster than natural method for example using pump and other machine than it can cause several kinds of problemsRefilling of these reservoirs are very time consuming and difficult

Ground water source

Floods

It is short lived events that can happen suddenly.It is caused by intense storms that produce more runoff than an area can store.Rivers, cyclones, storms can cause floods.Floods may be of following types

FloodsFlash floods

Coastal floods

Seasonal floods

It is caused by local rainfall in mountainous catchments.

Flash floods

Coastal floodsIt is caused by storm surge which is generated by a combination of wind friction and low air pressure.Seasonal floodsIt is caused by melting of snow or seasonal rainfall.

Flood ManagementIt’s aimed to

Reduce risk of floodsReduce vulnerability to floodsImprove preparednessImprove knowledge about the floods

Damage caused by flood

Loss of life, property, crops, and livestock.Disease related to interrupted water supply and sanitation.Damage to building and infrastructure.Pollution caused by flooding of waste deposits

Dams

Dams are built for storage of huge amount of waterVarious benefits of dams are…..Hydroelectricity generationEnsuring a year-round water supply.Flood control and soil protection.Irrigation during dry periods

Disadvantage of dams Some dams are loss much water

through evaporation.

Salts left behind by evaporation increase salinity of the water.

Growth of snail population in shallow permanent canal increase transmission of Schistosomiasis

Submergence of large area of land that might include fertile field and human settlements.

Resettlement and rehabilitation of displaced people.

A number of water related disease have been casually linked with the creation of water reservoirs e.g. Malaria, Schistosomiasis etc.

Mineral ResourcesAny naturally occurring inorganic substance is known as Mineral.Some mineral elements are essential for the formation and functioning of the body of all living beings.Mineral resources are broadly defined asElementsChemicalsCompoundsRocks

Use and exploitation of Mineral

Depending on the use, minerals can be divided into several broad categories

e.g. elements (for metal production, building materials and technology)

Minerals for chemical industry

Minerals for agriculture

Predominant mineral resources are non-metallic except iron and consumed at much grater rate that the element used for their metallic properties

Annual world consumption of a few selected elements are

Na and Fe are used at a rate of about 0.1 to 1.0 billion metric tons per year

N, S, K and Ca are used at a rate of about 10 to 100 million metric tons per year

Zn, Cu and Al are used at a rate of about 3 to 10 million metric tons per year

Au and Ag are used at a rate of about 10 thousand metric tons per year

Increasing demands from industry, transport and agriculture are a main cause of shortage of minerals and of great concern

Some of the suggested measure in this direction areRecyclingDeveloping more efficient technologiesDesigning smaller equipmentsFinding new uses of glass, ceramics, plastics and synthetic fibers

Environmental effects of extracting and using mineral

resourcesIt depends upon following factorsOre qualityMining procedureLocal hydrological conditionsClimateRock types Size of operationTopography etc.

Major environmental impacts of mining and processing

operation areDegradation of landPollution of surface and ground waterAir pollution due to emission of dust and gasesAdverse impact on historical and religious placesImpact on biological environment

Case study

Aravallis area of Rajasthan is rich in mineral wealth Hon’rable Supreme Court’s decision on Nov. 20, 2002 led to clouser of all these mines in RajasthanMountain plays a major role in control the climate. Hence peoples are force to join the maintenance of Mountain and Mines

Food ResourcesFood is essential materials for all living beings.Essential material with in the food is known as nutrients.Basic sources of food on the earth areCropsLivestockAnd aquaculture

World Food ProblemFAO estimates that about 840

million people remain chronically hungry.Whereas 800 million of them in developing countryThere are two types of food insufficiency1- Undernourishment2- Malonourishment

UndernourishmentUndernourishment is the lack of sufficient calories in available food.2500 calorie is required per day over the whole word.People who received less than 90% of their minimum dietary intake on a long term are consider Undernourishment.They don’t have enough energy for an active, productive life.

MalonourishmentMalonourishment is the lack of specific components of food such as proteins, vitamin or essential chemical elements.It is possible to have excess food and still suffer from Malonourishment due to lack of specific components.In richer countries people often eat too much meat and fat and too little fibers, vitamins and other components.

Changes Caused by Agriculture

Agriculture has both primary and secondary environmental effect.Primary effect is on site effect whereas secondary effect is off site effect.The main effects of agriculture on the environment is………..

Local changesThis occur at or near the site of farming.It include soil erosion and sedimentation downstream in local rivers. Regional changesIt include deforestation, desertification, large scale pollution, sedimentation in major rivers

Global changesIt include climate changes.

Effect of Modern AgricultureIt has both positive and

negative effects on environment.Modern pesticides have created a revolution in agriculture in the short termBut the long term effect on human body is very serious.

Effect of Fertilizers

It increases crop yields.They can be easier to store, apply.But these cause a no. of problems for exampleThey can be serious source of pollutionIncrease levels of phosphate in water are responsible foe entrophication.

Effect of PesticidesMajor agriculture pests are insects, nematodes, bacterial and viral disease and vertebrates.Pesticides are used to kill these pests and improve crop yields.But these cause a no. of problems for exampleEffects on non target speciestoxicity

Short term effect of pesticides on human health including acute poisoning and illness caused by relatively high dose and accidental exposureLong term effect of pesticides on human health including cancer, birth defect, immunological problems and other chronic degenerative disease.

Water Logging

Water logging problem arises either due to surface flooding or due to high water table.Productivity of water logging soil is poor due to less oxygenConstruction of canals has improved irrigation and increased the crop yield

SalinitySalinity refers to increased concentration of soluble salts in soil.It results due to intensive agriculture practices.Due to poor drainage of irrigation and flood waters, the dissolved salts in water accumulate on soil surface.These excess salts form a crust on the soil and injurious to survival of plants

Salinity can be controlled by improving drainage and land can be reclaimed by leaching.

Case studyStudies carried out by the biologist revealed that eggs of predatory bird species in north America had thin, fragile shells that broken before hatching due to traced residues of DDT and degradation products of DDE in water .

Energy ResourcesEnergy is present in a no. of forms e.g. mechanical, thermal, chemical, biological etc.It has great importance I our daily life.

Important energy resources are

Energy ResourcesCommercial fuels (Coal, lignite, petroleum natural gases and electricity).Non-Commercial fuels (fuel-wood, cow dung, agricultural waste).Primary energy resources (obtained from environments eg. (Coal, lignite, natural gases, solar ocean and geothermal energy).

Secondary energy resources (Donot occur in nature and derived from primary resources eg. (petrol, diesel, electrical energy).Conventional energy resources (Coal, petroleum, natural gases, water and nuclear energy).Non-Conventional energy resources (Solar, wind, geothermal biomass and nuclear energy)

Non-renewable energy resources (these are exhaustible and can not be replace once they are used eg. fossil fuels(Coal, oil, natural gases etc.) and nuclear power.Renewable energy resources (these are inexhaustible and can be replace once they are used eg. (Solar, water, thermal, geothermal and biomass energy.)

Growing energy needsToday underestimate the size and

scope of energy sources demands challenge ahead.For growing any country energy plays a very important role It is a fundamental goods for many other goodsInternational energy agency estimate that by 2030 it is likely world energy demand will increase by 45%

Case studyIncreasing demands of energy for growing the country and limited sources of are the serious problem now a days and it can be controlled by taking care full decision in developing the new resources of energy and stop the wastage of energy

Land ResourcesLand is a major constituent of the lithosphere and is one of the main component of environment beside, water and plants.Soil as a natural resource of the land The surface layer of the land is called soilIt is a renewable natural resource

It plays very important vital role in determination of the quality and composition of the biosphere

Some of the important function of the soil are

It provide mechanical support to the flora

Due the porosity and water holding capacity, soil serves as a reservoir of water and supplies water to the plants

It contains a no. of bacteria, fungi, protozoanes and many other microbes which help in decomposition and mineralization of organic matter

Land degradation and its causes

Land degradation refers to deterioration or loss of fertility or productivity capacity of the soilThe factors which are mainly responsible for land degradation areSoil ErosionSalinationWater loggingDesertificationShifting cultivation And landslides

Soil Erosion

Soil erosion refers to the loss or removal of the superficial layer of the soil by the action of wind, water and human actionMain factors which extent soil erosion areDistribution, intensity and amount of rainfall

Slope of the ground

Soil type

Vegetation cover

Soil mismanagement

Desertification

It is a slow process of the land degradation that lead to desert formationIt is like a skin diseaseIt may occur either natural phenomenon linked to climate change or due to abusive use of land Over cultivation, overgrazing, deforestation, poor irrigation practices all contribute towards desertification The top soil which takes centuries to build up can be lost in just a few years through such practices

Landslides

Human activities such as construction of road and railway , canal, dams and mining in hilly area have affected the stability of hill slopes and damage the productivity vegetation cover both the above and below roads.

Main causes of landslidesGeological causesWeak and sensitive materialsContrast in permeability

Morphological causesTectonic or volcanic upliftWave, glacial erosion of slope toeDeposition loading slopeVegetation removal Freeze and thaw weatheringShrink and swell weathering Anthropogenic causesLoading of slopeDrawdownDeforestationirrigation

Factor which initiate landslides

Water

Top removal

Strength reduction

Earthquakes vibration

Equitable use of resources for sustainable lifestyle

What is to be sustained? And for how longPractically it means the magnitude and quality of stock of natural resources.It must have half life of 500 to 1000 years still this is much longer than current planning according to world bankRenewable natural resources can be considered as a assets that could provide a flow of resourcesWhereas nonrenewable re sources are finite in quantity and quality

Four goal needed to attain a society based on sustainable consumption

Achieving complete reuse, recycle

Halving fossil fuel

Improve the quantity of material

Reduction transportation