Multidisciplinary Nature of EVS

7/24/2019 Multidisciplinary Nature of EVS

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Module 1:

Multidisciplinary Nature of

Environmental Studies

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Lecture 1:

Environmental study (EVS): It ismultidisciplinary subject that includes and/or integrates

Biology, Geology, Chemistry, Physics, Engineering, Sociology, Health, Anthropology,

Economics, Statistics, Computers, Philosophy, to the study o the en!ironment and the solution

o en!ironmental problems" It deals #ith e!ery issue that aects li!ing organisms"

Environment:A comple$ system that includes physical, chemical, biological, social, and

cultural elements" %hese elements are inter&lin'ed to each other in a complicated manner" Any

disturbance o any o these elements #ill threaten the structure o the en!ironment"

Broadly Environment is classified in to two types(&

(a) Natural Environment( In a natural en!ironment there is no intererence o human beings" Itis a sel regulated mechanism reerred to as )Homeostasis* means any change in natural

ecosystem is brought about by natural processes and it is counter balanced by natural changes in

other components o en!ironment"

(b) Manmade !nt"ropo#enicEnvironment:%he changes in en!ironment are due to

intererence o human acti!ities, particularly due to the #ide use enhanced technologies,

increased population etc"

1$1 Scope and %mportance of EVS:

Scope:

+" Environmental pollution control

ith the 'no#ledge o en!ironmental science e!erybody can control the pollution"

He/she can handle the #aste management and also loo' or #ays to control pollution on the

aspect o pollution control"

&$ Environmental mana#ement

%here are se!eral independent en!ironmental consultants #ho are #or'ing #ith the

'no#ledge o en!ironmental science e!erybody can control the pollution"

He/she can handle the #aste management and also loo' or #ays to control pollution on theaspect o pollution control"

Central and State pollution control Board they gi!e direction or controlling pollution due to

industrial de!elopment"

%here are se!eral current consultants #ho are #or'ing #ith go!ernment pollution control

boards, in!ol!ed in policy ma'ing, pollution control, and maintenance o ecological balance"

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-" Environmental studies in industry

En!ironmental scientists #or' to#ards maintenance o ecological balance. they also #or'

to#ards conser!ation o biodi!ersity and regulation o natural resources as #ell as onpreser!ation o natural resources"

ost o the industries ha!e a separate en!ironmental research and de!elopment section"

%hese sections go!ern the impact that their industry has on the en!ironment" 0ur en!ironment is being degraded by the rapid industriali1ation" %o combat this menace

there is a gro#ing trend to#ards manuacture o 2green2 goods and products"

'$ esearc" and development

3esearch and de!elopment has tremendous scope due to increment in public a#areness

regarding the en!ironment"

4ni!ersities conduct research studies in order to de!elop the methods to#ard monitoring and

controlling the source o en!ironmental pollution"

5ue to an increasing threat rom global #arming, many steps are being underta'en or the

reduction o greenhouse gases and the adoption o rene#able energy resources"

%hey generate a#areness no# regarding the use o solar energy or !ariety o purposes" %his

pro!ides scope o en!ironmental history in the ield o research and de!elopment"

$ Social *evelopment

6G0 7nongo!ernmental organi1ations8 help in creating a#areness regarding the protection o

the en!ironment and ma'ing the masses a#are o !arious en!ironmental issues"

%hey generate a public opinion in this ield" %hey #or' to#ards disseminating inormation

and in bringing about changes in political policies that are personally eect the en!ironment"

%he social dimension o this proession includes controlling population e$plosion through

organi1ing ad!isory a#areness camps"

%mportance:

It aims to de!elop en!ironmental ethics among us"

It helps us to understand our role and duties in the en!ironment"

It teaches us the importance o conser!ation o lie and biodi!ersity o the en!ironment"

It teaches us about sustainable de!elopment"

It pro!ides us suicient 'no#ledge about global en!ironmental problems and their abatement

and control"

1$&Need for +ublic !wareness

any people are not a#are o air pollution, #ater pollution, noise pollution and their ad!erseeect or impact on health" E!en some o the people are a#are about it but are least bothered"

Hence it is necessary to ma'e people a#are o it and educate them so that their each and e!ery

act/action #ould be eco&riendly"

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,b-ectives of +ublic awareness

9 Conser!ation o nature and natural resources9 Protection o species

9 Sol!e e$isting en!ironmental problems

+ropa#atin# +ublic awareness9 En!ironmental education

9 Go!ernment Institutions and 6G0s

9 ass media 73adio, %:, 6e#spaper89 Seminars and conerences

9 Entertainment

9 Public supported o!ements 7Street Plays, arch, E!ents8

9 Science centres

.uestions:

+8 5iscuss the importance o the ;En!ironmental Study


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Multiple /"oice .uestions:

+" En!ironmental study is a subject that encompasses

a8 All branches o science only"

b8 0nly social science"c8 Branches o sciences and social science"

d8 All branches o science, art and social science"

=" Biosphere is the

a8 En!elope o gases surrounding the earth"

b8 %he outermost layer o earth*s crust"c8 %he thin layer o organic matter containing all li!ing things on the surace o the

earth"

d8 6one o the abo!e"

-" orld En!ironment 5ay is obser!ed on

a8 April ==nd

b8 ay +st

c8 ?une @th

d8 0ctober =nd

" %he 6obel Peace Pri1e in = or contributions to#ards

en!ironmental conser!ation #as a#arded toa8 other %eresa

b8 Barac' 0bamac8 6elson andelad8 angari aathai

@" Global atmospheric temperatures are li'ely to be increased due to ,

a8 Burning o ossil uelsb8 ater pollution

c8 Soil pollution

d8 6one o these

0eys: 1(d) &(c) (c) '(d) (a)

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Lecture &:

1$ *epletin# Nature of Environmental esources

*epletin# Nature of 2orest:

%he problem o depletion and destruction o orests cause imbalances and enhance

threatening the sur!i!al o the human species" In the past + years the #orld has lostalmost hal its orest area" And, as indicated by reports o the A0 7ood and

Agriculture8 the Earth is losing on net e!ery year ++"= million hectares o !irgin

orest"

0!er the years, the area under orest co!er has decreased steadily, as orests ha!e been

cleared or agriculture, industry, housing, mining and other de!elopment acti!ities

li'e the construction o roads, rail#ays, and hydroelectric plants"

%his decline o orests, particularly serious in the case o tropical orests not only

increases the greenhouse eect by reducing the absorption o carbon dio$ide but also

aggra!ated the decline o #ater resources"

As the d#indling orest co!er, logically increases rainall runo, #hich a!ours

loods, soil erosion and reduces the amount that seeps into the ground to recharge

aDuiers"

Since the beginning o ci!ili1ation, as seen rom the Indus :alley Ci!ili1ation, people

ha!e been clearing land or agriculture to meet the ood needs o the e!er& gro#ing

population" ost orest communities ollo# a method o slash and burn or shiting

culti!ation, 'no#n as ?hum in the Indian subcontinent" %hey clear a patch o orest,

culti!ate crops on it, and abandon it the ollo#ing season" %hen they mo!e on to a

ne# area and ollo# the same pattern" %hey oten return to the same area ater a e#

years" %his method is more common in the hilly regions"

It is no# belie!ed that ?hum #as a good method o culti!ation as the land #as let

unculti!ated or a long period" %his allo#ed the orest to regenerate and the soil tostabili1e" 0nce the trees are elled, the soil becomes less ertile as it remo!es the

nutrient&gi!ing !egetation layer" %his also leads to se!ere soil erosion" I the land is

let to regenerate, the orest re&gro#s and the soil becomes stable"

%oday, though, this method o culti!ation causes e$tensi!e damage to the area" 5ue to

the increase in population, people are compelled to culti!ate on the same plot o land

more reDuently as there is !ery little orest area a!ailable" orests are also being

con!erted to permanent settlements" %hus, orests cannot regenerate, and, in some

cases, orest areas ha!e become #asteland #ithin a e# years due to reDuent

culti!ation"

2orest conservation measures:

Adoption o massi!e plantation 7commercial orestry8 and orest e$tensions 7social

orestry, argo orestry, urban orestry8"

Prohibition o mining acti!ities, dam construction , road,rails etc"

Enorcement o strict en!ironmental la#s and legal pro!isions 7reser!e orests, sacred

orests, reorestation, bloc' cutting8"

Public a#areness through aorestation and orest conser!ation programmes"


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*epletin# Nature of Soil:

Soil is the most important component o land"

It is the ertile surace layer o the earth capable o supporting plant gro#th" It is a

mi$ture o mineral matter, air, #ater, organic matter 7humus8 and organisms"

Soil pro!ides #ater and minerals to plants and ser!es as a habitat or bacteria, ungi

and many 'inds o animals" 4nortunately, industrial agriculture practices continue to damage and deplete this

!aluable natural resource"

Producti!e land is reducing due to dams, roads, rail#ays, urban settlements, actories,

canals, mines, and others"

hile intensi!e ploughing and monocrop agriculture systems ha!e caused nutrient

depletion and #ide&scale soil erosion, o!er&application o ertili1ers and pesticides

ha!e contaminated our soils andpolluted our #ater#ays"

Although there is e!idence that our ruits and !egetables contain lesser amounts o

nutrients and minerals than they did = years and @ years ago, it is not clear #hether

this is solely rom soil depletion or rom some other cause such as non&organic

arming practices and green har!esting as #ell" 0n an organic arm, soil Duality is maintained through the use o organic matter li'e

manure and ield #aste" %hese products are turned into useable nutrients by #orms,

nematodes, bacteria, mycorrhi1al ungi and other organism in the soil"

In contrast, soils on non&organic arms are oten lac'ing in soil biota" any o the

beneicial micronutrients in the produce all into the class o phenolics"

Plants ma'e phenolics to repel pests and i the plants are sprayed #ith pesticides they

ha!e little need to produce phenolics and so produce ar e#er, resulting in less

nutritious ood or us"

Measures for soil conservation:

Soil conser!ation is a combination o all methods o management and land use that

saeguard the soil against depletion or deterioration by natural or man&induced actors"

Planting co!er crops such as grasses, on unculti!ated land" %rees should be planted

along hill slopes"

Adoption o correct arming techniDues such as contour ploughing, terracing and strip

cropping"

Construction o chec' dams on steep slopes #hich pre!ent gully erosion and spread

gullies"

Creation o #ind brea's by planting lines o trees, hedges or ences #hich obstruct the

path o #ind thereby reducing its speed and hence reducing soil erosion"

Controlling gra1ing o pastures"

Suspending culti!ation or one season and more, so as to help the soil reco!er its

ertility"

*epletin# Nature of 3ater:

ater co!ers more than t#o&thirds o the Earths surace" But resh #ater represents

less than "@F o the total #ater on Earth" %he rest is either in the orm o sea#ater or

loc'ed up in icecaps or the soil, #hich is #hy one oten hears o #ater scarcity inmany areas"
http://www.sustainabletable.org/issues/pesticides/http://www.sustainabletable.org/issues/waterpollution/http://www.sustainabletable.org/issues/pesticides/http://www.sustainabletable.org/issues/waterpollution/


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orld#ide, the consumption o #ater is doubling e!ery = years & more than t#ice

the rate o increase in population"

%hough depletion o #ater resources is not a problem or e!eryone, the 4nited

6ations ood and Agriculture 0rgani1ation 7A08 notes that +"= billion people,

almost = percent o the Earths population, are e$periencing #ater scarcity" Another

@ million come perilously close to that threshold"

A large amount o #ater is #asted in agriculture, industry, and urban areas" E$cessi!e e$traction or irrigation #here ground#ater is slo#ly rene#ed is the main

cause o the depletion, and climate change has the potential to e$acerbate the problem

in some regions"

It has been estimated that #ith a!ailable technologies and better operational practices,

agricultural #ater demand could be cut by about @F and that in urban areas by about

--F #ithout aecting the Duality or economics o lie"

But most go!ernments do not ha!e adeDuate la#s or regulations to protect their #ater

systems"

5ue to the increase in population there has been a rise in the demand or ood, space

or housing, consumer products, etc", #hich has in turn resulted in increased

industriali1ation, urbani1ation, and demands in agriculture thereby leading to bothri!er and ground#ater contamination"

5rought and changes in routine #eather patterns are responsible or #ater depletion in

some areas"

/onservation measures for water resources:

Identiication and isolation o contamination sources"

Adoption o latest technologies in order to reduce the #aste generation and/or to treat

them eecti!ely"

Impro!ed and inno!ati!e planning o #ater resources"

Increased participation o the public, either directly or indirectly in sol!ing the crisis"

Enhanced co&ordination among the Agencies in!ol!ed 7both Go!ernmental and 6on&Go!ernmental8 or the cause o the 6ation"

*epletin# Nature of Minerals:

ining and reco!ery o mineral resources has been #ith us or a long time"

Human #ealth basically comes rom agriculture, manuacturing, and mineral

resources"

0ur comple$ modern society is built around the e$ploitation and use o mineral

resources" Since the uture o humanity depends on mineral resources, #e must understand that

these resources ha!e limits. our 'no#n supply o minerals #ill be used up early in the

third millennium o our calendar"

urthermore, modern agriculture and the ability to eed an o!erpopulated #orld are

dependent on mineral resources to construct the machines that till the soil enrich it

#ith mineral ertili1ers, and to transport the products"

%he presently a!ailable resources #ere created by earth processes and ater #e

e$haust them, more #ill de!elop in a e# tens o millions years, #hich is not in

human lie&spans" e are no# reaching limits o reser!es or many minerals"

Human population gro#th and increased modern industry are depleting our a!ailable

resources at increasing rates"
http://geology.uprm.edu/Morelock/9_image/minrsv.gifhttp://geology.uprm.edu/Morelock/9_image/minrsv.gif


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%he consumption o natural resources proceeded at a phenomenal rate during the past

hundred years and population and production increases cannot continue #ithout

increasing pollution and depletion o mineral resources"

%he geometric rise o population has been joined by a period o rapid

industriali1ation, #hich has placed incredible pressure on the natural resources"

imits o gro#th in the #orld are imposed not as much by pollution as by the

depletion o natural resources" As the industriali1ed nations o the #orld continue therapid depletiono energy and mineral resources, and resource&rich less&de!eloped

nations become increasingly a#are o the !alue o their ra# materials, resource dri!en

conlicts #ill increase"

By about the middle o the ne$t century the critical actorscome together to impose a

drastic population reduction by catastrophe"

/onservation and sustainable use of minerals:

A!oid #astage o mineral resources"

3ecycle, reuse o mineral resources"

4se o en!ironment riendly substitutes"

ull&cost pricing 7include the harmul en!ironmental costs o mining and processing

minerals in the prices o items8"

3edesign manuacturing processes 7use less mineral resources, produce less pollution

and #aste, mineral based #aste as ra# materials8"

Sell ser!ices instead o things"

.uestions:

1) State causes o soil erosion"

&) 5iscuss the en!ironmental problems arises rom deorestation"

) rite a note on depleting nature o en!ironmental resource&orest"

') E$plain in detail the ;depleting nature o en!ironmental resource& #ater


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+" hich o the ollo#ing is not the !iable protection against deorestation

a8 3educe the consumption o the orest related products

b8 Boycott products o the companies in!ol!ed in deorestation

c8 Pri!atisation o the orest land

d8 En!ironmental education

=" hich o the ollo#ing orms o land degradation is more common in India

a8 5esertiication

b8 Soil erosion

c8 and slide

d8 Soil subsidence

-" Ho# does dams aects deorestation

a8 0pen up pre!iously inaccessible orest to public

b8 Submerges orests

c8 5amages do#nstream ecosystem

d8 All o the abo!e

" hich o the ollo#ing is not true about deorestation

a8 Population e$plosion is one o the reason or deorestation

b8 Clearing o orest or agriculture causes deorestation

c8 5eorestation is ta'ing place only in de!eloping countryd8 Cash crop economy o third #orld is the cause o deorestation

@" hich o the ollo#ing statement about the orest is not correct

a8 orest reduces soil erosion

b8 Pro!ides recreational opportunities

c8 Pro!ides a source o economic de!elopment

d8 6one o the abo!e

0eys: 1(c)4 &(b)4 (d)4 '(c)4 (d)


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Lecture :

1$' 5lobal Environmental /risis

5lobal Environmental /risis elated to +opulation:

%he 4nited 6ations projects that the #orld*s population #ill be any#here bet#een "

billion to ++"= billion by =@, thats an a!erage o J" billion by that time"

Population gro#th in poor countries is damaging many local en!ironmental resources,

including resh #ater, trees and topsoil and that this in turn ma'es sur!i!al e!en harder

or the poorest people"

Ironically #e ocus our attention on the billion, actually the real source o

en!ironmental destruction are not the billion, but the +F, the handul o millionaires

and billionaires #ho o#n more, consume more, control more, and destroy more than

all the rest o us put together"

%he argument is that as long as humans continue to come up #ith scientiic

ad!ancements then the earth*s resources are ininite" Humans ha!e been ma'ing these

ad!ancements since the beginning o time, not e!en necessarily because the resource

ran out, but e!en because the ne# ad!ancement is more eicient"

or e$ample, to coo' ood humans ha!e s#itched rom burning #ood to burning

natural gas" Silicon #as used beore primarily or glass, no# it is a signiicant

component in microchips and optical ibres"

I humans re&arrange the resources they already ha!e to substitute or the ones theymay lose due to the gro#th, then no amount o population increase can dry up the

planet & in theory"

5lobal Environmental /risis elated to 3ater

ater is lie and is necessary or all ecosystems" Sound ecosystems ensure balanced

communities o species and rich li!elihoods" 3ich and di!erse li!elihoods are

undamental or our #ell&being and or the sur!i!al o the poorest"

0ur meals, our health and our li!elihoods depend on biodi!ersity" ood resources

rom agriculture or isheries, the di!ersity o medicinal herbs, #ater&consumingindustries, or tourist acti!ities de!eloped ne$t to la'es and ri!ers demonstrate that

#ater resources are !ital to nature and human" In addition, nature plays a role o

regulation and puriication o #ater resources, thus contributing to better #ater supply

and Duality"

or instance, the a!erage American uses +K gallons o #ater a day #hile the a!erage

Arican amily uses just @ gallons"

hile the #orlds population tripled in the =th century, the use o rene#able #ater

resources has gro#n si$&old" ithin the ne$t ity years, the #orld population #ill

increase by another to @F" %his population gro#th & coupled #ith

industriali1ation and urbani1ation & #ill result in an increasing demand or #ater and

#ill ha!e serious conseDuences on the en!ironment"


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Already there is more #aste #ater generated and dispersed today than at any other

time in the history o our planet( more than one out o si$ people lac' access to sae

drin'ing #ater, namely +"+ billion people, and more than t#o out o si$ lac' adeDuate

sanitation, namely ="K billion people, -J children die e!ery day rom #ater borne

diseases 7H0 =8"

0ne must 'no# that these igures represent only people #ith !ery poor conditions" In

reality, these igures should be much higher"

5lobal Environmental /risis elated to Land

Agriculture, particularly the use o industrial ertili1ers and other chemicals, has

undamentally upset the chemistry o the entire planet" Already, the use o ertili1ers

has more than doubled the lo#s o nitrogen and phosphorus compounds in the

en!ironment, resulting in #idespread #ater pollution and the massi!e degradation o

la'es and ri!ers"

E$cess nutrient pollution is no# so #idespread, it is e!en contributing to the

disruption o coastal oceans and ishing grounds by creating hypo$ic 2dead 1ones,;" Gi!en our current practices, uture increases in ood demand #ill dramatically

increase #ater pollution and ecosystem destruction through agricultural eluent"

Ironically, the ertili1er runo rom armlands compromises another crucial source o

ood( coastal ishing grounds"

and use is also one o the biggest contributors to global #arming" 0 the three most

important man&made greenhouse gasses L carbon dio$ide, methane and nitrous o$ide

L land use and agricultural practices, including tropical deorestation, emit -

percent o the total" %hats more than the emissions rom all the #orlds passenger

cars, truc's, trains and planes, or the emissions rom all electricity generation or

manuacturing"

%he !ast majority comes rom deorestation, methane emissions rom animals and rice

ields, and nitrous o$ide emissions rom hea!ily ertili1ed ields"

5lobal Environmental /risis elated to Sanitation %here are at least ="K billion people in the #orld #ithout impro!ed sanitation" ost o

these ="K billion reside in rural Asia and Arica"

Impro!ed sanitation is deined by the orld Health 0rgani1ation as connection to a

public se#er, connection to a septic system, a pour&lush latrine, a simple pit latrine or

a !entilated impro!ed pit latrine"

But technically, e!en access to ;impro!ed< sanitation does not sol!e the problem

because con!entional pit latrines usually ail to saniti1e and they contribute to

ground#ater pollution"

Also, septic systems and se#age treatment plants oten discharge into the

en!ironment #ith little or no saniti1ation or nutrient remo!al" In turn, the eluent and

sludge produced at se#age treatment acilities oten pollutes ground#ater, la'es and

seas"

So in actuality, ar more than ="K billion people need to gain access to eecti!e and

sustainable sanitation"

Sanitation can impro!e social and economic conditions or all, but especially or

impo!erished communities"
http://www.who.int/water_sanitation_health/publications/facts2004/en/http://www.who.int/water_sanitation_health/publications/facts2004/en/


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It oers empo#erment and saety, particularly to #omen and girls in the areas that are

oten #ithout sanitation, by pro!iding a pri!ate and digniied en!ironment or

urinating and deecating"

E!en i the sanitation crisis can be communicated to and understood by more people,

the need to ind sustainable alternati!es to con!entional approaches or both

de!eloped and de!eloping countries remains"

Sustainable and ecological sanitation calls or a holistic approach"

1$ Ecosystem

An ecosystem is a biological en!ironment consisting o all the organisms li!ing in a

particular area, as #ell as the non&li!ing, physical components o the en!ironment #ith #hich

the organism interact, such as air, soil, #ater and sunlight"

Structure of Ecosystem

An ecosystem comprises t#o main components(7i8 Bioticinclude plants, animals and microorganisms and

7ii8 !bioticmainly include sunlight, substratum, #ater, minerals, carbon dio$ide and

o$ygen"

Biotic componentsare the li!ing things in the ecosystem" rom the tiniest bacteria to the

largest mammal, all need abiotic components in order to sur!i!e" %hey need air to breath and

light to photosynthesi1e, or e$ample"

I the ecosystem is small, the biotic actors #ill rely on the abiotic components more than i

the ecosystem is large" I there is much di!ersity in an ecosystem the biotic actors rely on

each other as #ell as on the abiotic components"

/omponents of Ecosystem

Biotic Abiotic

Autotrophs Heterotrophs

Producers Consumers 5ecomposers

Herbi!ores Carni!ores

+roducers


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In an ecosystem, producers are those organisms that use photosynthesis to capture

energy by using sunlight, #ater and carbon dio$ide to create carbohydrates, and then

use that energy to create more comple$ molecules li'e proteins, lipids and starches

that are crucial to lie processes"

Producers, #hich are mostly green plants, are also called Autotrophs"

In a process called photosynthesis, plants con!ert radiant energy rom sunlight into

chemical energy" %hey use this chemical energy to con!ert #ater and carbon dio$ideinto sugars" Plants use some o the sugars they create to build plant parts li'e stems

and lea!es" Some is used as acti!e energy or gro#th, reproduction and

photosynthesis" %he rest is stored #ithin the plant as a 'ind o energy reser!e"

/onsumers

Consumers are heterotrophic organisms mostly animals, #hich generally ingest and

s#allo# their ood"

%he ood o consumers consists o organic compounds produced by other li!ing

organisms"

*ecomposers %hese are saprophytic 7sapro M to decompose8 micro organisms such as bacteria and

ungi, #hich obtain their ood rom dead bodies to producers and consumers and their

organic #astes"

!biotic componentsare non&li!ing components in the en!ironment" %his can be either a

chemical or physical presence" Abiotic components all into three basic categories(

Climatic actors include humidity, sunlight and actors in!ol!ing the climate"

Edaphic reers to soil conditions, so edaphic actors include soil and geography o the

land"

Social actors include ho# the land is being used and #ater resources in the area"

.uestions:

1) hat is the impact o gro#ing population on en!ironment>

&) rite a brie note on en!ironmental crisis related to #ater"

) 5iscuss the sanitation status in de!eloping country>

') In #hich manner the ;land< is one o the most !ital actors or our e$istence> Ho#>

) E$plain the Ecosystem"

6) E$plain the structural components o ;Ecosystem


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+" Population e$plosion #ill cause

a8 Socio&economical problems

b8 ood scarcity

c8 Energy crises

d8 All o the abo!e

=" Population gro#th in de!eloping countries as compared to de!eloped countries is

a8 6egligible

b8 Slo#er

c8 aster

d8 At almost the same gro#th rate

-" %he threat to global en!ironmental balance ast depletion o natural resources

are all outcome o

a8 0!er!ie#s o natural resources

b8 Population e$plosion

c8 Pollution

d8 All o the abo!e

" hich o the ollo#ing is a possible producer in an ecosystem>

a" Plants some bacteria capable o producing their o#n ood

b" Animals

c" Human beings

d" ish

@ %he energy lo# in the ecosystem is

a" unidirectional

b" bidirectional

c" multidirectionald" cyclic

K hat is the term or a collection o similar ecosystems>

a" ecosystem

b" Ecotone

c" biome

d" community

0eys: 1(d)4 &(c)4 (b)4 '(a)4 (a)4 6(c)$


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Lecture ':

/lassification of Ecosystems

An ecosystem may be natural 7li'e orest, la'e, ocean etc8 or man&made 7such as an

aDuarium, a crop ield etc8, temporary 7li'e a rain ed pond8 or permanent 7li'e a la'e, orest,

etc8, aDuatic 7such as pond, ocean etc8 or terrestrial 7li'e grassland, orest, etc8"

a8 Natural Ecosystem:6atural Ecosystem may be terrestrial 7li'e desert, orest, etc8 or

aDuatic li'e pond, ri!er, la'e etc" A natural ecosystem is a biological en!ironment that

is ound in nature 7e"g" a orest8 rather than created or altered by man 7a arm8"

b8 !rtificial Ecosystem: Humans ha!e modiied some ecosystems or their o#n beneits

and these are Artiicial Ecosystem" %hey can be terrestrial 7crop ield, garden etc"8 or

aDuatic 7aDuarium, dam, manmade pond etc"8"

7errestrial ecosystems

%errestrial ecosystems are ound e!ery#here apart rom #ater bodies" %hey are broadlyclassiied into(


17/27

7"e 2orest Ecosystem

%hese are the ecosystems #here abundance o lora 7plants8 is seen and they ha!e a large

number o organisms li!ing in relati!ely small areas" %hereore, the density o lie in orest

ecosystems is !ery high" Any small change in the ecosystem can aect the #hole balance and

collapse the ecosystem" %hey are again di!ided into e# types"

7ropical ever#reen forest:%ropical orests #hich recei!e an a!erage rainall o N to inches in a year" %hese orests are mar'ed by dense !egetation comprising o tall

trees #ith dierent le!els" Each le!el gi!es shelter to dierent 'inds o animals"

7ropical deciduous forest:5ense bushes and shrubs rule here along #ith broad

le!els o trees" %his type o orests is ound in many parts o the #orld and large

!ariety o lora and auna are ound here"

7emperate ever#reen forest: %hese ha!e !ery e# numbers o trees but erns and

mosses ma'e up or them" %rees ha!e spi'ed lea!es to minimi1e transpiration"

7emperate deciduous forest:%his orest is ound in the moist temperate regions #ith

suicient rainall" inters and summers are #ell deined and #ith trees shedding their

lea!es during #inter"

7ai#a:Situated just south o the arctic regions, %aiga is distinguished by e!ergreenconiers" hile the temperature is sub1ero or almost si$ months, the rest o the year it

is bu11ing #ith insects and migratory birds"

7"e *esert Ecosystem

5esert ecosystems are foundin regions recei!ing an annual rainall o less than =@cm" %hey

occupy around + percent o all land on the planet" 5ue to !ery high temperature, intense

sunlight and lo# #ater a!ailability, lora and auna are !ery poorly de!eloped and scarce"

:egetation is mainly bushes, shrubs, e# grasses and rarely trees" ea!es and stems o these

plants are modiied to conser!e #ater" %he best 'no#n desert plants are the succulents li'e

spiny lea!ed cacti" Animal lie includes insects, reptiles, birds, camels all o #hom are

adapted to the $eric 7desert8 conditions"

7"e 5rassland Ecosystem

Grasslands are ound in both temperate and tropical regions o the #orld but the ecosystems

are slightly !arying" %his area mainly comprises o grasses #ith !ery little amount o shrubs

and trees" ain !egetation is grasses, legumes and plants belonging to composite amily"

any gra1ing animals, herbi!ores and insecti!ores are ound in grasslands" %#o main types

o grasslands ecosystems are(

1$ Savanna: %hese tropical grasslands are seasonally dry #ith e# indi!idual trees" %hey

support large number o gra1ers and predators"

&$ +rairies:%his is temperate grassland" It is completely de!oid o trees and large shrubs"

Prairies can be categori1ed as tall grass, mi$ed grass and short grass prairie"

7"e Mountain Ecosystem

ountain lands pro!ide a scattered but di!erse array o habitats in #hich a large range o

plants and animals are ound" At higher altitudes harsh en!ironmental conditions generally

pre!ail, and only treeless alpine !egetation is ound" %he animals li!ing here ha!e thic' ur

coats or pre!ention rom cold and hibernate in #inter months" o#er slopes commonly are

co!ered by conierous orests"


18/27

!8uatic ecosystem

An aDuatic ecosystem is an ecosystem located in a body o #ater" It comprises aDuatic auna,

lora and the properties o #ater too" %here are t#o types o aDuatic ecosystems, arine and

resh#ater"

7"e Marine Ecosystem

arine ecosystems are the largest ecosystems #ith co!erage o nearly +F o the Earths

surace and containing JF o the planets #ater" %he #ater in arine ecosystems has salts

and minerals dissol!ed in them in high amounts" 5ierent di!isions o marine ecosystems

are(

0ceanic( %he relati!ely shallo# part o the ocean that lies o!er the continentalshel"

Proundal( Bottom or deep #ater"

Benthic( Bottom substrates"

Inter&tidal( %he area bet#een high and lo# tides"

Estuaries

Salt marshes

Coral rees

Hydrothermal !entshere chemosynthetic bacteria orm the ood base"

any types o organisms are ound in marine ecosystems including bro#n algae, corals,

cephalopods, echinoderms, and shar's"

7"e 2res"water Ecosystem

In contrast to the arine ecosystem, resh#ater ecosystems only co!er "NF o the Earths

surace and contain "JF o its total #ater" %here are three basic types o resh#ater

ecosystems(

Lentic:Still or slo#&mo!ing #ater li'e pools, ponds, and la'es"

Lotic:ast&mo!ing #ater li'e streams and ri!ers"

3etlands:Places #here the soil is saturated or inundated or at least some

time"%hese ecosystems are home to amphibians, reptiles and almost +F o #orld*s ish species"

aster mo!ing turbulent #ater typically contains greater concentrations o dissol!ed o$ygen,

#hich supports greater biodi!ersity than the slo# mo!ing #ater o pools"

%mportance of ecosystem Ecosystem study gi!es inormation about the amount o a!ailable solar energyin an

area"

It gi!es data about the a!ailability o mineral elements, their utili1ation and recycling

in the en!ironment"

Inter&relationships bet#een !arious types o organisms as #ell as bet#een organismsand abiotic en!ironment can be determined"


19/27

Producti!ity o producers and consumers is 'no#n"

%he ma$imum number o producers and consumers o !arious categories #hich can

be supported in the ecosystem is 'no#n"

Inormation can be gathered about #ays to increase producti!ity, eect o pollution,

degree o e$ploitation along #ith conser!ation o resources"

2ood c"ain

In an ecosystem energy lo#s rom one trophic le!el to another" A trophic le!el represents a

group o organisms, #hich are either predators or they get consumed" All organisms in an

ecosystem are lin'ed to one another based on their nutritional needs" %his relation bet#een

the indi!iduals constitutes a linear chain called the ood chain"

4ltimately a ood chain al#ays begins #ith the producers" %he !arious components o the

ood chain can be deined as a group o organisms in #hich there is transer o ood energy

through a series o repeated eating and being eaten

A ood chain sho#s ho# each li!ing thing gets ood and ho# nutrients and energy are passedrom creature to creature" ood chains begin #ith plant&lie, and end #ith animal&lie" Some

animals eat plants, some animals eat other animals"

%#o types o ood chains are recogni1ed in nature" %hese are Gra1ing ood chain and 5etritus

ood chain"

1$ 5ra9in# food c"ain:%he gra1ing ood chain starts rom green plants passes on to herbi!orous primary

consumers and ends #ith carni!orous animals" %hus the nutrition produced by plants utili1ing

energy o solar radiation are used in the ollo#ing three #ays &

7i8 4sed or respiratory acti!ity o the plant

7ii8 Get decayed

7iii8 ay be consumed by herbi!ores

In a gra1ing ood chain there are basically our trophic le!ies & Auto trophic, primary

consumers, secondary consumers and tertiary consumers" Gra1ing ood chain is the most

important ood chain in nature"


20/27

/"aracteristics of 5ra9in# 2ood /"ain

a8 %hese are directly dependent upon solar radiations as the primary source o energy and the

producers 7green plants8 synthesi1e their plant biomass by the process o photosynthesis"

Producers orm the irst trophic le!el"

b8 Herbi!ores or primary consumers eat upon the producers and orm the second trophic

le!el"

c8 Herbi!ores are in&turn eaten by dierent categories o carni!ores orming the higher

trophic le!els"

d8 Gra1ing ood chains are longer ood chains and they al#ays end at decomposer le!el"

&$ *etritus food c"ain:

5etritus or decomposing ood chain begins #ith dead organic matter goes to micro organisms

and then passes on to organisms that eed on detri!ores 7organisms that & eat detritus8 and

their predators" Ecosystems o this type are less dependent on direct solar energy" 0n the

other hand they depend on the supply o organic matter produced by another ecosystem"

5etritus ood chains are seen in those areas #here there is plenty o organic matter in the soil

as in temperate orests" In a detritus ood chain organic matter to start the chain comes rom

outside" %he main source o organic matter is the lea all rom the trees producing lot o

litter" %he allen lea ragments are acted upon by saprophytic ungi and bacteria and areeaten by a small group o animals"

%hese animals include crabs, copepods, insect lar!ae, grass shrimps, nematodes etc" All these

animals are called detritus consumers or detri!ores" %hese animals are in&turn eaten by small

ish" %hese small ish orm ood or large ish, ish eating birds constituting the large

carni!ores"

/"aracteristics of *etritus 2ood /"ain

a8 Primary source o energy is dead organic matter called detritus #hich are allen lea!es,

plant parts or dead animal bodies"

b8 Primary consumers are detriti!ores including proto1oans, bacteria, ungi, etc #hich eed

upon the detritus saprophytically"c8 5etriti!ores are inturn eaten by secondary consumers such as insect lar!ae, nematodes, etc"


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d8 5etritus ood chains are generally shorter than gra1ing ood chains

e8 In nature, detritus ood chains are indispensable as the dead organic matter o gra1ing ood

chain is acted upon by the detriti!ores to recycle the inorganic elements into the ecosystem"

5ra9in# 2ood /"ain *etritus 2ood /"ain

+" It al#ays starts rom green plants totertiary consumer le!el"

+" It al#ays starts rom detri!ores"

=" Green plant is the irst organism to absorb

solar energy"

=" Bacteria, ungi are the irst one"

-" %hey do not help in nutrient cycle" -" %here is an in!ol!ement o nutrient cycle"

" Generally large organism maintains this

type o ood chain"

" Generally, small organism maintains this

type o ood chain"

2ood web

A food webis a graphical description o eeding relationships among species in an ecological

community, that is, o #ho eats #hom 7ig" +8" It is also a means o sho#ing ho# energyand

materials 7e"g", carbon8 lo# through a community o speciesas a result o these eeding

relationships" %ypically, species are connected by lines or arro#s called 2lin's2, and the

species are sometimes reerred to as 2nodes2 in ood #eb diagrams"

A ood #eb diers rom a ood chain in that the latter sho#s only a portion o the ood #eb

in!ol!ing a simple, linear series o species 7e"g", predator, herbi!ore, plant8 connected by

eeding lin's" A ood #eb aims to depict a more complete picture o the eeding relationships,and can be considered a bundle o many interconnected ood chains occurring #ithin the

community"

All species occupying the same position #ithin a ood chain comprise a trophic le!el #ithin

the ood #eb" or instance, all o the plants in the ood#eb comprise the irst or 2primary

producer2 tropic le!el, all herbi!orescomprise the second or 2primary consumer2 trophic

le!el, and carni!ores that eat herbi!orescomprise the third or 2secondary consumer2 trophic

le!el" Additional le!els, in #hich carni!ores eat other carni!ores, comprise a tertiary trophic

le!el"
http://www.eoearth.org/article/Community_ecology?topic=58074http://www.eoearth.org/article/Community_ecology?topic=58074http://www.eoearth.org/article/Energyhttp://www.eoearth.org/article/Carbonhttp://www.eoearth.org/article/Specieshttp://www.eoearth.org/article/Predationhttp://www.eoearth.org/article/Herbivoryhttp://www.eoearth.org/article/Plant?topic=49480http://www.eoearth.org/article/Herbivoryhttp://www.eoearth.org/article/Herbivoryhttp://www.eoearth.org/article/Community_ecology?topic=58074http://www.eoearth.org/article/Community_ecology?topic=58074http://www.eoearth.org/article/Energyhttp://www.eoearth.org/article/Carbonhttp://www.eoearth.org/article/Specieshttp://www.eoearth.org/article/Predationhttp://www.eoearth.org/article/Herbivoryhttp://www.eoearth.org/article/Plant?topic=49480http://www.eoearth.org/article/Herbivoryhttp://www.eoearth.org/article/Herbivory


22/27

%mportance of food c"ain and food web: ood chains help in understanding ood relationship and interdependence among

!arious organisms in an ecosystem"

ood #ebs are important tools in understanding that plants are the oundation o all

ecosystems and ood chains, sustaining lie by pro!iding nourishment and o$ygen

needed or sur!i!al and reproduction"

%he mechanism o transer o ood, energy and nutrients through !arious components

o nature can be studied"

%he mo!ement o some to$ic substances 7li'e 55%8 in the ecosystem, sprayed to 'ill

the pests and insects, through the !arious trophic le!els, their accumulation at the

highest trophic le!el, etc" can be studied" 7%he phenomenon is 'no#n as biologicalmagniication"8

%he disruptions in populations in the ecosystem due to o!er&hunting, poaching, global

#arming and habitat destruction result in ood scarcities leading to e$tinction can be

e$plained"


23/27

Ecolo#ical +yramid

An ecological pyramid is a graphical representation designed to sho# the number o

organisms, energy relationships, and biomass o an ecosystem" %hey are also called Eltonian

pyramids ater Charles Elton, #ho de!eloped the concept o ecological pyramids"

%he producers orm the base and the carni!ore occurs at the top o ood chain" %he dierentorganisms in the pyramid are present in the seDuence #ise and include the producers at the

base #hich are ollo#ed by the herbi!ore" %hese are ollo#ed by the primary carni!ore #ith

the lion at the top"

%hey can be upright #hich means that the base is larger in si1e and it decreases as #e mo!e

up#ards" %hey can be in!erted also #hich means that the base is smaller in si1e and it

increases as #e mo!e up#ards" It can be spindle shape #hich means that the base is thin

along #ith the top but the middle part is broad"

%he ecological pyramids are o three types(

7i8 Pyramid o energy

7ii8 Pyramid o biomass and

7iii8 Pyramid o numbers"

1$ 7"e pyramid of ener#y

%he energy pyramids gi!e the best picture o the o!erall nature o the ecosystem"

Here there #ill be gradual decrease in the a!ailability o energy rom the autotrophs higher

trophic le!els" In other #ords, there is decrease in energy lo# rom autotrophs at successi!e

trophic le!els"

In the course o energy lo# rom one organism to the other, is considerable loss o energy in

the orm o heat" ore energy is a!ailable in the autotrophs is the primary consumers" %he

least amount o a!ailable energy #ill be in the tertiary consumer" %hereore, shorter the ood

chain, greater is the amount o energy a!ailable at the top"

+" %he energy pyramid al#ays upright and erect"

=" It sho#s the rate o energy lo#s at dierent trophic le!els"

-" It sho#s that energy is ma$imum at producer le!el and minimum at the carni!ores le!el"

" At e!ery successi!e trophic le!el there is a loss o energy in the orm o heat, respiration

etc"


24/27

&$ 7"e pyramid of biomass

Pyramid o biomass is the graphic representation o biomass present per unit area o dierent

trophic le!els, #ith producers at the base and top carni!ores at the tip"

%he total amount o li!ing or organic matter in an ecosystem at any time is called Biomass"

+" Pyramid o biomass sho#s the total biomass at each trophic le!el in a ood chain"

=" Pyramid o biomass can be in!erted or upright"

E$amples(

In a terrestrial ecosystem, the ma$imum biomass occurs in producers, and there is

progressi!e decrease in biomass rom lo#er to higher trophic le!els" %hus, the pyramid o

biomass in a terrestrial ecosystem is upright"

In an aDuatic habitat the pyramid o biomass is in!erted or spindle shaped #here the biomass

o trophic le!el depends upon the reproducti!e potential and longe!ity o the member"

$7"e pyramid of numbers

%hey sho# the relationship bet#een producers, herbi!ores and carni!ores at successi!e

trophic le!els in terms o their number" It sho#s the number o organism at dierent le!els"

Pyramid o numbers can be either upright or in!erted"

%here #ill be a gradual decrease in the number o indi!iduals rom the lo#er to the higher

trophic le!els in an upright pyramid" %he smaller animals are preyed upon larger animals and

smaller animals increase aster in number o organism at each stage o ood chain, ma'es a

triangular igure that is 'no#n as pyramid o number"

%his may be studied by ta'ing the e$ample o trophic le!els in grassland"

%he grasses occupy the lo#est trophic le!el and they are abundantly present in the grassland

ecosystem" %he mice occupy the second le!el. their number is less than compared to the

grasses"

%he sna'es, #hich eed upon the mice, are ar less in number #hen compared to the number

o mice" %he ha#'s, #hich occupy the ne$t trophic le!el, eed upon sna'es, and the number

o indi!iduals in the last trophic le!el is greatly reduced"


25/27

In the parasitic ood chain, the pyramid o numbers is ound to be in!erted" Here, a single

plant or tree might support !arieties o herbi!ore" %hese herbi!ores li'e birds in turn, support

!arieties o parasites li'e lice, bugs that outnumber the herbi!ores"

SubseDuently each parasite might support a number o hyperparasites li'e bacteria and ungi,

#hich #ill outnumber the parasites" %hus rom the producer le!el on#ards, to#ards the

consumers, in the parasitic ood chain there is a gradual increase in the number o organisms,

instead o the usual decrease"

As a result o this, the pyramid becomes in!erted in the parasitic ood chain" %here is a

gradual increase in the numbers o indi!iduals rom autotrophs to the higher trophic le!els"

.uestions:

1) hat is ;ood Chain E$plain/Brie diagrammatically"

&) hat is ;ood eb E$plain/ Brie diagrammatically"

) E$plain the structure o Ecosystem&orest"

') E$plain the structure o Ecosystem&aDuatic"

) Ho# does )Bio&mass* )Energy&lo#* are related in ecological pyramid>

6) 5iscuss in detail the signiicance o ;Ecological Pyramid


26/27

+" A ood #eb consists o

a" A portion o ood chain

b" Producers, consumers decomposers

c" Interloc'ing o ood chains

d" A set o similar consumers

=" A trophic le!el reers to

a" Area in the trophic

b" An organism*s position in a ood chain

c" An organism*s position in an ecosystem

d" An organism*s position in a biome

-" %endency o pollutants to become concentrated in successi!e trophic le!el is

'no#n as

a" Bioremediation

b" Biomagniications

c" Biopiracyd" Biorhythm

" Eutrophication is

a" An impro!ed #ater Duality status o la'es

b" %he result o accumulation o plant nutrients in #ater bodies

c" A process in the carbon cycle

d" A #ater puriication techniDue

@" %here are OOO types o ecological pyramids

a" 0ne

b" ourc" %hree

d" i!e

K" %he pyramid #hich cannot be in!erted in a stable ecosystem is

a" Pyramid o number

b" Pyramid o ood

c" Pyramid o energy

d" Pyramid o biomass

" %he primary producers in orest ecosystem area" Chlorophyll containing trees and plants

b" Herbi!ores

c" Carni!ores

d" Bacteria and other microorganism

N" In an aDuatic ecosystem phytoplan'ton can be considered as a

a" Consumer

b" Producer

c" Saprotrophic organism

d" acroconsumer

J" argest ecosystem o the #orld is


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a" Grassland

b" orest

c" 0ceans

d" 5esert

+" an&engineered ecosystem consists o

a" 5esert and orest ecosystem

b" Grassland and marine ecosystem

c" Agriculture and aDuaculture ecosystem

d" 6one o these

0eys: 1(c)4 &(b)4 (b)4 '(b)4 (c)4 6(c)4 (a)4 ;(b)4

Documents

Multidisciplinary Nature of EVS