Environment by shankar ias academy

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SHANKAR·.lAS ACADEMY
Pl t o.1742, lst ·lo r, 18th Main Road, rma J':'ag~, Olen'nai- 60 040.
• Phone: 044-26216435, 64597JZ1,43533445, Mobile ~44416b·r ~
www.shankariasaca~emy.coin
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Facebook Group: Indian Administrative Service ( Raz Kr)

. - ----SD4!CMS richn and endemiSQl as well as of agro-biodiversity, India, with only
m supports~~ astounding 8.1% of the world's piodiver~ity. She also supports
a~Well.as18%of-tlieworld's cattle popula~on. Infact, an estimated 70o/o ofIndia's
eDlmCJaent locally on natw:al ecosystems for subsistence means of livelihood, including fuel,
J, 'att:'r, ~d_security of~ealth. Conseq~ently, the country's biodiversity facesimmense pressure.
1b vironmental problemsinIndia are growing rapidly. The increasingeconomic developmentand a
r 1 'ing p I 1 ation are putting a.strain on the envirorunen t, b"od·versity, and the country's na ral
re ourc s. IndustJ:ial pollution, soil erosion, deforestation, poachfug, rapid indust?alization,_·~rbanization,
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• a1 d uegradati~n are all worsening-problerns. Overexploitation of the country s resourc s, b it and or
h <1~ re~u ted ·n the environmental degradation. ·
· There is ·so far a positive of information for the student and general public on Environment.
I a1n pleased to therefore ~troduce this book "ENVIRONMENT'', 1-vhich covers on Environmental
E o ogy, Bio-di ersity and Climate Change 'tNTfh reference to In d ia, a pioneering attempt by the
SHR KAR lAS ACALJE~Y, presented in a ~oncise and visually appealing format to raise the level of
lr...n~lwledge and awareness among the people from aH _ v~?lks of life.
This book is exclusively prepared for all aspirants who prepare for Civil Services Ex~mination and
other Competitive exams.
ccwe Need-Ecol~gical Grow.th-Not.Mere Economic-Gr-owth!'.·-----··-
uNature Pr~tects IfShe Is Protect.edn
ALLTHEBEST
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D. SHAI'iKAR
DIRECTOR
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SHANKAR lAS ACADEMY
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• us Year UPSC Questi~.n paper analysis ..............................~..........................:......,.................;....:.;,i. . ..
PART·I
ENVIRONMENT ECOLOGY. . .
1. ECOLOGY···································-······································································-·····················."...............3-9
, J!. . PY OF EC ~ LOGY... .... .-....................:...........:......................................................................3
r ENVIRONMENT & ITS COMPONENTS ..................................................................................3
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• • • 0 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1. · r·1 I~"' ' ·s OJ: · ·1 rros 'Sl"F ·1-· .... '- ._,j - · ... ~ .. . ..... ....... ......... ...... . , .. .. .... ..... ...... . . .. .. .. . - .......... .... ..... ... ...... ... ...10-20
)> ENERGY FLOW ....................·......................................................·--···-··-··--···--··..........................10. .
> fl10D CHAIN ..........:.......:....... ............................................................................. .......................10
.r FOOD vVEB ......:.........................................................................................._..................................11
> ECO OGJC J·...t-P"YAA~ -1 D .... .. .... ............................................ ................,~..................... ....:.......12
> POLLUTANTS & TROPHICAL LEVEL ..................................................:................................14
? BIOTIC JNTERACTION ........ .... ... ......................................... ..~ ...................................................15
? BIO-GEOCHEMICAL CYCLE ...................~....................... ....:·. ~:·.~--~~~:.:·:~----~..............................15
;... ECOLOGICAL SUCCESSION .... ...............................................................................................19
3. l 'ERRES"fRlAL "ECOSYS EM......................................:.........................-................'............................21-30
> TUNDIZA ..................................=: ..............................................................._....................................21
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> FOREST ECOSYSTEM..............'.........................................................................:..~-:~.~..-.-:.~.............2f____--
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}> INDIAN FOREST -ra.r'PES.......................:................................................-.....,..........:....................23
)>. DEFORES'fATION ......................:.,._.·......:......................................................................................24
> GRASSl~AND E OSYSTEM.. ...........................................................- ..................... ....................26
, DESET<T ECOSY TF 1 (TI-JAR ~.. COL )...................................'.....................................;.........27
) DESERTIFICATION .................~···· ...........................~................................_.......:....................:....30
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N.. . ............................................... . . ....................34................................................ .
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"' N ERVATI N PR RAMME.................................................40
l't::t1 .......:.····..····..·····..···..... ...._...............'.......- ..........................·11
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F, .............................................................:.........:....:..................................................45
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E T ASTAL ENVIRONMENT ..................................................... 48 .·
1 P tJTJON .......................................................................:..........................49-70
liT NT................................................................................................................................-49
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• ! :>( _ l . 1TJ ·yN ............................ ......................... ..........................................- .
• FL ASH ............,........................................................................'...........................................52
· ..... · -· ·r~ ~: ·o ·:............... ............................::.......................... ............................ ....... .55
> ATER POLLUTION ............................................................................,......................................55
....,IL . LLU.flO ........................................................................................................................5b
ISE f>()LLliTION ................................,.....................................................................................60 -·
DIO CTI E POLL TIO I ........................................................ ... ..... ................................... 61
);:- E- ASTE .............................. ...............................~- ......................................................................... 62
~ LID ; STE .................. ........ ......................'............. .............................·..~ .................................65
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> BlO-REMEDIATlON ....................................................................................................................67
> E VIRO l'v1E TAL Hv1PACT ASSESSMENT............:....:................:....................................... 69
·PART-II .
BIO IVER ITY
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6. .BIODIVERSJTY....u ................... - ............................................................... .-.................................. ......72-75
)> B10Dl ERSI'f¥...........................~.............................~......................................................._...........72. .
LEVEI..S OF BIODIVERSI.TY........................................................................................................72
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EASUREMENT OF BIODNERSITY.......................................................................................73- . ~. .
r BIODIVERSI1"Y SERVICE$...............................................................~..........................................74
,.. ODES OF CONSERVATION.......:............................................................~.....- ......................75
BOTANICAL GARDEN&. ZOO........................................................................................... 7
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I HICALCLASSJFICATION .............................................................76
DIVERSITY ...................................................................................................................:.. 80
> INDJ N WILDLIFE .............................................................................·····-··································82
....19'Pl~ DlVERSITY OF lNnlA..- ..···-················---······~···········-~·-········:·~·-········-~---···············-··-85-98. . . .
)> RED BOOK DATA..............................................:···············........................................................... 85
)> IUCN CLASSIFICATION ......:~................................................._..:......,........................................ 85
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)> CRJTICALLY ENDANGERED MAMMALS...........·:..:..............................................................87
}:- ENDANGERED MAMMALS ........................................:_:.......,.....:...............................................88
);> VlJI_NERABLE.MAMMAl5............................................:..................._.......................................90
)> 1.fARl, E lvlit ,1J,IALS.................................................................................................................. 91
EG . A'11lJG :iv1A.! ilvlA ......................................................................................................... 91
> A 1ARSUPIAL...........-...........................................······....·············:·····'······........................·............... 92
')::. CRJTir T.Y EJ'TDANGERED BIRDS ......................................................·.................................92
)> CRJTICALLY ENDANGERED REPTILES .....................,..·.::..................................................... 94
.;--_ - D CALLl L 'DA1 GEJ?ED F. S :· ..................................."..............................................:...95. ~ . -..
);> CRITICALLY ENDANGERED SPIDERS & CORJL ...............·..........:.......•............................. 9?
> BIRD. 11GRATJO 1 ............. ............ ........... .............................:........... ........ ............ ..................... 96. .
)> W1LD LIFE·DISEASE.....................................................................................................................97
SPECIES EXTL ~CTlON ..................................:..... .......................................::-:·........................... 97·----- -- ,.
:;::. :MA N- ANI viAL CONFLICT................................................................................................:......98
9. PLANT DIVERSlll' OF INDIA ........................................................................................:............99-107
> PLANT CLASS!FICATION .........................................................................................................99
> EFFECT OF ABIOTIC COMPONENTS ON PLANTS.................................-............................ 99
r LlJSECTIVOROUS PLANT........................................................................................................100
> INVASlVEAUEN SPECJES ,...:....................................................~............................................102
r INVASIVE ALIEN FLORA OF INDIA ...............................................:..................................... 102
r MEDICINAL PLANTS .........'.....:..:..................................: ...:.....................:.........-...................104
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r TREEGIARAC-r-ERS ................~...................................._..................~.; ....................................:105
10. MARINE ORGANISM ......·...........................................................................-..................................108-110
r ~Kl'ON -~·-··· ······················~········--···· ::··:................................................................................ 108
)> PHYTO:PLANKTON ....................................................:......................~..................................... 108
,.. ZCXJ..Pl..ANKTON .............................................................,........................................................110
;,;; SEA GRASS......-:-....................................................................:.........................•.......................... 110
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• • •• . . . . . ......... ...................... ~•••••••••••••••••••• ~..... . ........ .... . . . .. t. .. . ... ... . 112-126
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N UARY & NATIONAL PARKS ........................................................112
V. 11 N RESERVES & COMMUNITY RESERVES ...................................:..1i4
PROTEC..JED AREA$............:.............................................................................114. .
• SA ED GROVES OF INDIA..........................................................................................115
• EXPORT PROHIBI1'ED ~EMS........................................................................................116
. L BAL lT<JI JIATIVE
• AN AND BIOSPHER£............................................................................:......................117. . .
• BIOSPHERE RESERVES...................................'........-...........:............................................. 117
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• NATIONALBIOSPHERE RESl!RVE PROGRAMME·:.................................................119
• WORLD.NETWORK OF BIOSPHERE RESERVES .......................................................121
• BIODIVERSn'Y HOTSPOl"S.............................................................................................122
• WORLD HERITAGE SITES ...................·...........................................................................124
12. CONSERVATION EFFO~S .........................................................................................................127-139
· · }> PROJECT TJGER ...........................................................................:........:....................................127
}:> PROJECT ELEPHANT ........................................................................,........................................130
. ~ VULl 'URE............................................:.,......................................................................................132
? oNEHOR1 ED RHJ TJCBEtms~·-·~,-~--~_·:·~,~~~:~~~~: :::~:: ::~.................................................:............135
~ PROJECT SNOWLEOPARD...................................................................................................... 136
}> SEA TURTLE PROJECT .............................................................................................................. 137
}> CROCODILE CONSERVATION PROJECT ...................................... ................. ...................... 37
}> PROJECI' HANGUL....................................................................................................._.............. 138
}> CAP'flVE BREEDING ................................................................................................................138
GA NCES DOLPHI 1 .......... .. ... ........... .. ........ ..... .......... ..·.. ............ .... ......... ...... .......... .............. .... 138
PART-Ill
CLIMATE CHANGE
-13 CLIMATE CHANGE.......................................................................................................................l-:11-149
):> GLOBAL WARMING ........................._.........................................................................................141
~ -6-REEN HOUSE EFFEcr.:.::.:::..:::.:.:::::.::-..:.......:.:......-...~..:......::.................................................. 142
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,. GREEN HOUSE.GASES.............................:..........................................................:....................143
}> CLIMATE FORONG.............................................············................·····:·············--·--·--···:..........146. , ............· ·: .... ...
GLOBAL WARMING POTENTIAL......................................................................:....,.....-,..... 147
}> GLOBA EMMISSJON&............................................................................................................ 8
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5. ZONE l >LE...................................................-....................~··························· 157 161.................................... -.
IMPACf ( IMATE CHANGE- INDIA ..............~........................~..................~......~........"....162_167
> AGl' CUL'fURE&F~ .:...................::.............................................:...............:162
> ·VATER STRESS · .&WATER INSECURfi'V.............................................................................-..163.
> SE.t JEVEL RJSE....................................."........................................ . 1·64• 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 . . . . . . . . - .. . • • .. • . . . . . . . . . . . . •
> EC< YSTEM & BiODIVERSITY..................................................................·....................-::........165
)> CL TECHANGE&HEALTH .....................................................................................:....;.i66
17. MITIGATION STRATEGJ.ES...............................................:··········--·--········----.......~.....................168-172
)> CAl.., BON SEQUESTR..tl'lON ................................................................................................... l68
> AJ BC..)N ' 11'-lK ...................................................................................................... ..................... 169
)> CARBON CREDIT.............:.............................................:·--·······················································170
)> C.ARBGN-0 FSEmNG .................................................. ...............................:..... .. .....:..:....:. 70
)> CARBON·TAX .....................:......................................-...............................................................:.17.1
.:. "r---GEO-E:l .G:i1 'EERI G.................................................................................................................l7 .
-18. INDIA AND CLll1ATE CHANGE ...............·.................:............................................~................173-l<Jn. .
> INDIA'S POS1TION ON-CLIMATE CHANGE ...................:....:..........:..............................:. 173. . . . .
)> OBSERVED CLIMATE AND WEATHER CHANGES IN INDJA....:...................................-174'
)> CORRECT ACTlONSFO ADAPTATl01 A 0 ltflTlGATIOi 1 ........... ........ . ....... ....... ..... 17-1
)> NATIONAL ACTION PLAN.ON CLIMATE CHANGE.......................................................175. .
? INDIAN NE1WORK ON CLIMATE CHAN6E ASSESSMENT.........................................:181
}:;> NATIONAL COMMUNICATION (NATCOM) ....................:......................................... .......182
)> J 1DIA'S POLICY STRUCTURE RELEVANT TO GHG NIITIGATION ..............................183
)> GI~~EN BUILDING ·······················································:····································--·····················184. .
> GRIHA ...............:............................................~................................,~...:·....................................... 185
> NATION~L INITIATIVE ON CLIMATE RESILIENT.AGRlCULTIJRE ........ .................:.. 188
> · BSE G REENEX .........................................................;..............".................................................... 189 •
> 24 OTHER CRITICAL ENTITIES ..........-...:...................:.......................::..................................190. .- . .
19. CUMATF. C'JIANGE ORGANJSATJQNS ........:...............................................:..........................191-203. . .
~ tJ1'J ·c::c ........~.................................:·.-...........................~........................~.-........-..:.......:.-............-..:....191
)' KYOTO PROTOCOL .......:...................._.........................:.:...........:......................... ..........:......... 191
> , BALI MEET ...:.....:.....................................................:..............:...~........._~···::········::······--·:._.......... 193
> COPENHAGEN S,lJMMl1'........................................::.~.......................~~-············· ··· ·---·--·· ··········194
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NM NT FA ILJ11 ..............................................................:................199
T A ICULTIJRE .........................................................................................199
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TI N L GREEN HOUSE GAS INVENTORIES PROGRAMME..................................201
G EE1 .ECONQ~ ...,..........~........_.......................:·······················::········:·:................................202
PART-IV
AGRICULTURE
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20. GRICULTURE........................................................~.·············································.·····················-·····205-221
}> CROP AND ITS CLASSIFICATJON._......................................................................................206
}> CROPPING SYSTEM AND PATTERN ....................................................................................210
}> FARMING SYSfEM....................................................................................................................212
}> SUSTAINABLE AGRICULTURE..............................................................................................213. . . . ..
}> J TEGRATED FAR1v1ING SYSTEM....................................................................................·.....214. . .
)> SOIL SCIENCE ............................................~...............................................................................217
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21. ACTS AND POLICIES ....................................................................................................................223~229
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J> "TJLD LIFE PROTECTION ACT 1972 .........:...................................................................~..-2-23-
~ ENVIRONMENTALPROTECTION ACT 1986......................................................................224
> NATIONAL FOREST POLICY 1988.............................................................:............................225 , .
.. -:>-· .BIOLOGJCAL DfVERSITY ACT 2002 ......................................................................................225
}> SCHEDULE TRIBES AND OTHER FORESf DWELLERS ACT 2006 .................................226 ,-
~ COASTAL REGULA'nON ZONE ...........................................................................................227. .... .. .. . . - .
)> WE'fLAND RULES 2010..................................................~.....................................~......................228
J> NATION GR-gEN l"'RIBUNAL .....~......................................................................._................... 228
J;> THE OZONE DEPLETING SUBSTANCES RULES ........................:.:.....................,..............228
22. INSTITUnON AND MEASURES-.~..•··· ...............................-...·...........;-;.,..~...;;-;·...;;-:.;~;:;.~.......~..............229-235
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"' NATIONAL VIDE LIFE ACTION PLAN ............................................................................,..229
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> NATIONAL AFFORESTATION AND.ECO-DEVELOPMENT BOARD ............................229
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> CAMPA.........................................~...............:...................................................................,a·.-•.:.·.-..,.-230:
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> ,·JOINT FORESf MANAGEMENT.....................................-. ~.................~................"..................230. . . .
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NATIONAL BAMB()() ~I.SSION ......................................~.........................................:...........232
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LJll........................................................................................................ 233
TIONAI. Cl.EAN ENERGY FUND .....~.....................................:.......~:::::::::::~::::::::~:::::::::::233
NTI .A ONAL MISSION FOR ELECTRIC MOB~ .....~....................~..................................234
),> - SCIENCti M.XPRESS- BIODIVERSITY SPECIAL .......:...............:.....:...'..................-..:-:........... 234
> MANGROVE FOR FUTURE .........................-.......................................................................... 235
23~NVJRONMENTA.L ORGANISATIONS ...................................~......................................~..............236-239
> AN1~1AL WELFARE BOARD ................................................................................................... 236
)> CEN'TRAL Z()() AU~rHORITY .............,.................·..............................................................:... 237
)> NATIONAL BIODIVERSITY AUTHORITY ......................:...................................................237
)> WILDLIFE CRIME CONTROL BUREAU ....................................................................'.......... 238
~ N TI01 TAL AKE CONSER AT ON PLAN......................................................................... 238
> NA110NAL GANGA RIVER BASIN·AUTHORffY ............................................................. 239
24. INTERNATIONAL ENVIRONMENTAL CONVENTIONS....................................................240-255
> U. TED N_A'IJQ...:.'-::.-·.~9 .!FERE CE 0 l E. ..'TI Oil. 1E T./·~..·:c DE.'E OP ~E: T ..... ~40
>• CONVENTION ON BIOLOGICAL DIVERSITY (CBD)........................................................ 241
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-RAMSAR CONVENTION ON WETLANDS.'......................................................................... 246
CITES .......................................................................................:..................................................... 247
>_. THE IVILDLIFE TRADE 10NITORJ rc NETIVORK {TRJ FF C, ..................................... 248
);> CONVENTION ON THE CONSERVATION OJ~ MIGRATORY SPECJES (C 15)............. 248
> COAUTION AGAINST 1TJLDLJFE TRAFFICKING (CAWT) ............................................ 248
INTERNATIONAL TROPICAL TIMBER ORGANIZATION (ITT0) ................~~............... 249
> UNITED NATIONS FORUM ON FORESTS (UNFF)...............................;...._............:........... 249
> IUCN ::.:..........................................:.............................................................................................. 250
? GLOBALTIGER FORUM (GTF) ...................·............................................................................ 251
~ - ___SI.OCK.HO.LM CONY~NTION. """::·""~"""'•·"."'"""""""""'·······............................................ 252
? BASELCONVENTION .........................·.....·~..............................:......................................·........252
)> ROTTERDAM CONVENTION·-.......:........................................................~....................::...:....253
>- UNITED NATIONS CONVENTION TO COMBATDESERTIF1CA'110N......................... 253
}.> INTERNATIONAL WHALING COMMISSION (lWC) ..................................:.................... 254
viENNA CONVENTION AND MONTREA~PROTOCOL ......................................~......... 254- -. .
25. ENVIRONMENT ISSUES AND HEALTH EFFECTS..-............................................................256-261
GLOSSARY .........................................................................................................-:-.·.... 2.62. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • .. • • • • • • a
AUPENDlX ....................................--...............- ...............................................2701: ........................... •••••••• •• •••• •• - -
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viu statements:
it · i n rm 11y greater in the lower
n1p r d to the higher latitudes.
1 ng th mountain gradients, biodiversity
i. n rmally greater in the lower altitudes as
~ mp d to the hig}: r altitudes. · ..
· 1i h ~f the statem nts given above is/are correct?
1 nly
b. 29nly
c. Both 1 and 2
d. Neither 1 nor 2
2 ~- ~ee ofthe followng criteria have contributed
io the recognition ofWestern Ghats- Sri Lanka
and indo-Burma regions as hotspots .of bio.-
. ·e s·ty.
J.. Spet?es richness
3.
- 5.
ege a 'on ensit •
Endemism.
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Ethno-bolanical importance
Threat perception
6. .Adaptation of flora__and fauna to warm and
humid conditions
Which three of the above are cor~~.<;t__~Ii_tg~ia in this
context?
a·. 1, 2 and 6
b. 2,4and6
c. 1, 3 and 5
d. 3,4and 6
3. Biodiversity forms tl1e basis for l1uman
existence in the following ways :
Cl. Soil formation
b...Ptevention of s~il erosion
c. Recycling of waste
d. Pollination of crops
Select the correct answer using the codes given
below:. .
a. 1,2 and 3 oruy.
. 2,3 and 4 only
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1. W!'ic~- of ~he following~be threats to the
btodtverstty ofa geographi~al area ?.
1_. Global warming
2. Fragmentation of habitat ·
3. Invasion of alien species ·
1.:.- .Promotio~ of ··vegeranan1sm ·
Select the correct answer using the codes given
below. · . ·
a. 1, 2 and 3 only
b. 2 and 3 only
c. 1 and 4 C?nly
d. 1, 2, and 4
2. lnwhich one among the following categories
of protected areas in India are local people
not allo'lved to col ect and use the biomass?
a. Biosphere Reserves
b. National Parks
c. Wetlands declared'under Ramsareunventrorr ·
d. WHdlife Sanctuaries
3. Consider the following protected areas
1. Bandipur
· .,....2~---"Bhitark«iml<a-----
3. Manas
4~ Sunderbans
Which of the above are declared !iger Reserves?
a. ·1, 3 and 2 oruy
b. 1~ 3 and 4 ·only
c.· 2, ~ f1!l~ 4 only •
d. 1, 2,3 ~d 4
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m
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hi h r inf II that supports luxuriant
t ti growth.
nfluence of different bio geographical
otic and. inv~sive. ~c~de~ have not been
.._•....,.duced m this regton.
d. has less human interference.
12. If a tropical rain.forest isremoved, it does not
regenerate quickly as compared to a tropical
deciduous forest. This is because ·
a. the soil of rain forest is deficient in nutrients
b. propagules ofthe trees in a rainforest ha ·e poor
viability
c. the ~ain forest species are slow-growing . . ·
d. exotic species invade the fertile so}l of rain forest.
-13. When the b.ark of a tree is removed in a
circular fashion all around near its base, it
gen~rally dries up and dies because
a. 'Vater from soil cannot rise to aerial parts.
b. Roots are starved of energy
c. Tree is infedl:d-b oil microbes
d. Roots do not receive oxygen for respiration
CLIMATE CHANGE
14. c_ons!der the fo!J:~~~n_g :_ _
1. Photosynthesis
2. · Respiration
3. Decay of organic matter
4.. VoJcanic action
WhJch of the above add carbc;l dioxide t"o the carbon
cycle on Earth 1 ·
a. 1.and 4 only ·
b. 2 and 3 only
c. 2,3 and 4 only
1 2 3 and 4
-ll-: _Co_nsjder - ~~e _fol1owing statemen~s :
Cholorofluorocarbons, know.n as ozone-
depleting substances, are used
1. in the.production of plastic foams .
2. in the production of tubeless tyres
3. in cleaning certain electronic c0mpo~ents
4. as pressurizing agents-in aerosol cans
Which of the statements given above is/are correct?
a. l, 2 and 3 only
b. 4only
c. 1, 3 and 4 only
d. 1, 2,-3 and 4 •

t "'' t rv r th d it
th ultraviolet part of th ol n.
i I
. .1n1 s1 n~
Uthe solar radiations.
wr ] nts? •
d. th infrared ~of the solar radiation
.. .
ion of ozone hole in the Antartic 13. lbe acidificationofoceans is incre~sing. Why
ha.. 1: een a cause of concern.. .'Vhat is this phenomenon a cause of concern?
e the reason for the formation of this 1. The growth and survival of calcareous
ole?
· cs - C'.' .. ;tJm · ntt oposp encturb 1 ence;
d =n o .: of chlorofluoro carbons ·
p.,.. ~e"!'l e f -r j e t pola r f n · ·<lnd
stratospheric douds; and inflow of chl?ro
1
__
1
_c_._ Absence of polar front and stw:1tospheric douds;
z d iJ .flcv.- of me ane and dlloro fluorocarbons.
d. Increased tempera~re at polar region due to
global' ~arm_~g
17.
a.
b.
c.
Regarding '"'carbon credits'', which one of the
following statements is not correct? ,
The. carbon credit system was ratified in
conjunction with the-Kyoto Pro~ocol
Carbon credits are awarded to countries or .
groups that have reduced greeftheuse gas~s
below their emission quota. .
The goal of the ca~bon c:redit system is to limit
the increase of carb(ln einission quota . ·
arbor crcj·tS are 1!a ed at a pri e f~ d from
tim to time by theUnited Nations Envuorunept
rogramme.
•
. . . .
phytoplankton will be adversely affected.
2. . The growth and survival of coral reefs will be
adversely affected.
3. The survival of some.-animals that have
hytoplanktonic arvae wjll b~ ad 'ezsely
affected.
4. he cloud seeding and formation of clouds.will
be adversely affected.
Which of statements given above is I are correct ?
a. 1,2 and 3 only b, 2 only
c. 1 and 3 only d. 1,2,3 and 4
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5. Among the following SJates,.whjch one has
the most suitable climatic conditions for the
cultivation of a l~ge variety of orchids with
minimum cost ofproduction, and can develop
an export ·oriented industry in this field.?
a. Andhra Pradesh
.• rui achal Pradesh
t c._~adhya Pr~~esh ,
d. t: a radesh
6. Asandy and saline area is the natural habitat
of an Indian ?nima] species. The.anima] has
no predato~s in that area but its existence
is threateneq due to· the destruction of its
habitat. 1-Thjch one of the foJJowing could
be that animal ?
a. lndian wild buffu)o
b. Indian wild ass
c. Indian wild boar
d. Indian Gazelle
7. The '1
Red Data Books' published by the
International Uniov. for Cons.ervation o
Nature and Natural Resources (lUCN)
contain lists of ·
a. Endemicplant and animal species present in the
biodiversity hotspots.
Threaten d plant and animal species.
c
. What is th differ::n:c:-b~·tw:----=====.
ryx and Chiru? n the antelop
a.
b.
Oryx is adapted to live in h t d· .
whe!eas Chiru is adapted to liove~stand areas
semi-desert areas of cold high ~pes and
. mountams.
Oryx IS poa0ed for its antlers whereas oiliu.poached for Jts musk. · Is
c. Oryx e:xists inwestern India orJ.y whereas Cruru
eXIsts m north-east India only. _ .---
d. ~one of the statements··a, b, and c given abov
IS correct. e
5. Consi~er the following :
1. Black-necked crane
2. Cheetah
3. Flying squirrel
4. Snow leopard
'7JUch of the abo e are naturally found in India?
a. 1,2 and 3 only
b. 1,3 and 4 only
c. 2 and 4 oJ:lly
·.:.:.:.:.1,2,.;L<IDd-4.....
6. Cpnsider the following ldnds of organisms
1. Bat
2. Bee
3. Bhd
Which of the above is/are polli.nuhng agent I agents?
a. 1 and 2 only
b. 2 only
c. 1 and 3 only
d.l, 2 and 3
7·. Which one·ofthe following groupsofanimals
_elongs to the _cate.gor.y.-of ..end-arigei:ed
species?
a. Great Indian Bustard, Musk Deer, Red Panda
and Asiatic WHd Ass
b. Kashmir Stag, Cheetal, Blue Bull and .Great
Indian Bustard ...
c. Protected sites for conservation of nature & c:
natural resources in various countries.
Snow Leopard, Swamp Deer, Rhesus Monkey
and Saras (Crane) ·
of the statement given above is I are correct?
3
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d. Lion-tai~d Macaque, Blue BuJl,
Langur and Cheetal
•
Hanuman
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L.JeoC'OinJ)4~r i roorganisms to the surface.
utri ts to th surface.
Hon-dwelling·organisms to the surfare.
f the sta~em~ts given above is/are correct?
1 and ... •
2only
2and3
d. 3 ·nly
9. The 20~ Tsunami made people realize that
mangroves ~an serve as a ~eliable safety
_TV-I . ENVIRONMENT'~
What would ~appen if phytoplankto of
oceafscompletely destroyed for som~reaso~
1. The ocean as a carb<?n sink would be ad
1affected. . verse y
2. Thefood chains in the ocean would bead 1
affected. verse y
..· :
3. The density of ocean water would drasticall
deqease. Y
Select the using codes given bel~w :
a. 1 and 2 only
b. 2 only
c. 3 only
d. 1,2 and 3
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9. .Wilh reference to the wetlands of India,
consider the following statements; ~
!,
h dge ag~st. coastal calarnit.ies. How do l .
a gr ves fu ction ns a· s.. fety e ge?
&
'The country's to al geographical area under the ;
~
categ,oryof"1'et ~~.~.record~d rnore · · Gujcuat t. . .
a. The ma.ngroves swaps separate the human as compared to other States. ~
2. .In India, the total geographical area of coastal ~
·w tlan s ·s arger than hat ehl land "'.e trnd.-<>or-t-~
settlementsfrom thesea by a wide zone in which
t-l f ~e :u:·•'-er Ev~ r ,'er re o t
b. Themangroves rovide both food and medicines
w.hlch people ar~ in need of after any natural
disaster.
W[rich of the statements gjven abov~ is/are co
a. . 1 only
-b. 2only
The mangroves trees are taU with dense canopies c:
and ser.·e as an excellent shelter during a cyclone Both 1 and 2
Neither 1 nor 2or tsunami . d.
d. fhe mangr.:H·es trees do T IOt get uprooted by
storms and tidesbecause of their extensive roots_
ect?
10. There is a concern over the increase in 10. Vnltures which used to be very common in
harmful algal blooms in the seawaters of Indian countryside s(>me years age arerarely ·
..I
India. That could be the causative factors seen no 'adays. This is attributed to · ;
;
for this phenomenon 7 a. the destruction of their nesting sites by.new t
i
1. Discharge of nutrients from the estuaries. inva~ve species. 1
2. Run-off.from the I~d during the monsoon. b. a drug used..by cattle own~rs for treating their ,~..
·diseased cattle.3. Upwelling in the seas.
Select V"ae correct answer from the' codes given c. scarcity of food available to them f
below : d. a widespread, persistent and fatal disease among , ,
ili~ la. 1 only
b. 1 and 2 only
2 3 y 1
,2 3
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T &: POLICIES
t I dia, the
ds:
rt ( ontrol) Act, 1947.
Min~al Development (Regulation)
u t m~ et, 196.2
Indi 1 For st Act, 1927
"<=!' ~ abo:ve Acts have relevance to I bear~g on
I tversrty conservation in the country ? . ·
1 and 3 only
b. 2,3 and ~ only
c. 1,2,3 and 4
d. None of the above Acts
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14.·The Natipnal Green...T. .b ·
· ·· n unalA
enacted in consona· . ct, 2010 w as
nee Wllh h" h
following·provisions of th c~ ':.1~ .. ~f the
India? e onshtUtion of
1. Right to healthy environm t .
2. part ~fpart ofRightto life :~de;~~;Ias a
Pro":Js_ion of grants .for raising the 1 l f
·a~mllll9trntiGn·in the Schedtd d A efve o· e reas· or ····- ·-
_welfare ofScheduled Tnbes underA:rtide 275(1)
Which of the statements giv~n above iS/are correct?
a. 1 only. • · .
b. 2 only
c. Both 1 and 2
d. · Neither 1 nor 2
15. How does National Biodiversity Authority
·(NBA) help in .pro t ect ing the Indian
agriculture?
1. "NBA checks the b]opiracy and protects the
indigenous and tra~tional genetic r~sources.
2. NBA diriTtJy monitms aJitfsapenise-rr-lte
scientific research on genetic modification of
crop plants. ·
3. Application for intellectual Property Rights
related to geneticI biological resources cannot
be made without the approval of NBA.
Which of the statements given above is/are correct?
a .. 1 only
b. 2 and 3 onlvJ
c. 1 and 3 only
d. ·.1... 2 and 3
CURRENT AFFAIRS
19. Recently, "'oilzapper was in the news. What 16. Governm-en-t-of -India encourages · the
is it 1. . · · - • cultivation of :sea buckthorn< What is the
a." · It is an eco-friendly technology for .the importance of this plant?
remediation of oil sludge and.oil spilJs. a. It helps in controlling soiJ erosion and in
tis e atest echnoJogy developed for under. preven!ffig desertification.
·sea oil explorati~. b. It is a rich source of biodie5e1.
c_ 1 is a gen e ticalJy engineered high biofuel c. It has nutritional value and is well-adapted to
yielding ma~e variety. live in cold areas ofhigh altitudes.
s he ]a te~t tec'hno]ogy to control the d. Its timber is of great·commercial value.
acc::Ja4erna11y caused flaines from oil .ve1l._s_.___.li.-~- ---------~- ~------1
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y
nother, with its source
............_ . t a place only a short
o the co st of Bay of Bengal
flo ing into the sea. This is an
im rtant site of wildlife and bio-diversity
nd protected area. Which one of the
f llowing (oiil'd he this ?
. .Bhitarkanika
Chandipur-on-sea
c. Gopalpur-on-sea
d. Simlipal
2011 - Answers
7. A Particular Stat · In ·
h
. . e In d1a ha the following
c aractenstics :
1. It is located on the same Latitude w hich passe
through northern Rajasthan.
2· lt has ovey BO% of its area under forest cover.
3· <iver 12% of forest cover constitutes Protected
Area Network in this State.
W)Uch one anwng the.follq,,,:ing Stn_ cs h;Js a he
above characteristics? ·
a. Arunachal Pradesh
b. Assam
c. J1imachal Piac;l~.h
d. Uttarakhand .··
20i2 - Answers
ll(b),. 12(a), 13(a), 14(c), 15(d), 16(b), 17(d), 18(c), ll(d), 12(d), 13(a), iii(~), 15{c), 16(a), 17(a)
19ta), 20ta)
tQ.no. 7 is disputed)
2011
UPSC MAINS EXA~iiNATION
PA ERl.
2012
-
Evolution of Green Benches (12 marks) Causes and the Extent of 'Desertification' in India
and Remedial Measures (25 marks)
Impact of C.C. on Indian at r resources (12 marks) ·Endosulphan ~25 marKS)
Phase IV of tiger monitoring programme (5 n1arks) Tiger tourism (25 n1arks)
• ·PAPER%
2011 2012 .
'E-waste (5 mar.lqij Permaculture (12 marks}
Diminishing popuJation of VuJture (5 marks) CBD (5 marks) .
. En~onment Sustainability (S marks) ·Billion Acts of Green (2 marks)
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·:-ECOLOGY-o.
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1 uniti .
rth- .. a·t
i ~ nd nt n n igh ttring
~,......"'n"'.,.,.·lled soo ti s. Th )yare ·
n ' ithiR a maj r community
n~ completely independent
' and nutrient dyn mi s are
t of lichen ona cow dung pad.
tructureof a community
mmunity the , wnb r 9f specie~ and size
ft. :Tf fU aln Y<H _ -. at y. , ('( l!n"l 1't r n a_:
C'r .everal s ecies.
~ t: t.ni 1 e1 < c rs Ern i1 th
characteristicof the co1nmunity as' ell as the pattern
f hiT!' i.1 .
The characterisb pattern of the community is
: .::.... ~ · .._;: c-C:L.C c.. I ". ; hi l is ' t .:..n 1 c cJ !..
played ) various population, their range, the
f rea t e~· j a it, the di 'ersity of s ~;..: ie
in 1e mmum the spectrum of i1 ter
bern een them.
co- ~s e
An ecosystem is defined as a structural and
fun ional unit of biosphere consi ting of con1muruty
of living beings and the physical environment, both
interacting and exchanging materials bet-ween them..
ro •stem ·s a· complex set of r ] a tion~ 1ip
among theliving resources, habitats, and residents of
an area. It includes plants, trees, animals, fish, birds,
miGro-organisms, water, soil, and people.
EcOsystems vary greatly in size and elements
but eadt is a functioning unit _of nature. Everything
hat Jives in an ecosystem is dependent on the
r ecies and · f' mt:n . that are also pa~t ,f t a
ecological community. If one part of an ecosyst m
1 damaged or disappears, it has an impact on
e rything else.
"yst m is healthy(~.. sustainable)
f> J·m nt. livP in ~aJ nc~ ar d a e
, t Jves. Ecosys~m can
tr oraslarg asentir fo ·st.
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iffr .n •1 tw .- vir H
osystern.
Components of Ecosy$lem
TI1e omponentsof thee osyst m is categorised
·nto abiotic of non-Hv.in · and ·o ·c of living
components. Both the components of ecosystem and
n rir 1 m e1 l re sam .
•
1. mpo nt
Abjotic c m p onents are the inorganic and non-
living parts of the world. The abiotic part consists of
soil, wa r, ai1·, and lig~t e~ergy etc. ll also in olves
a ]ar~e number of chemical hke xvoen, rutrooen
tc. an p 1ysi al processes inc u ing volcanoes,
earthquakes, floods,eforest fi.res, climates, ~nd
w al r onditi ns.
A i tic factors are th e m o st jmportant
determinants of where and how well an organism
ex ·. L ·n v·rC' ent. Alt ough the e ac o ~
intera t ith ach oth r, OJ e sin gl I tor an limit
the range of an organism.
a) Energy
Energy from the sun is essential for maint~ance
of life. In the ase of plants, the SW1 ire tly supplie
the nece sary energy. ince animals cannot use solar
nergy directly they obtain it indirectly by eating
plants r animals or both. Energy determines the
djstril: ution of organism~ in_th_e en ironment.
b) Rainfall. .
Water is essential for all liVing beings. Majority
of bioch 'nu al reactions tak p1a .in an aqu 0
m dillin. · ~ h lps l r gul, e bu ·Iy len r. i It.. .
Further, water bodies f rm th habit,pt f r many
aquatk plants and animals.
c) Temperature
Temp r ·ture-isacritical fact r f th vinmn nt
. ;d b ... l t J· iufl 1 ·' ;. · · , ! ·,1 •• •
C"Jrga i.'m: • n tol , t o 1ly l1 <
temp,~ratllrt' ctn i humidity. •
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wid v ri ty-
small animals
ts f pl r -
pw t and nutrients. Organisms
qu ~c. Terr trial animals live
qu tic lants, animal and microbes live in
teras ell as in th s a. Some microbes live
in h water nts under the s~a.
(i)
J J
at rials:
rganic compound such as proteins,
r h} drat ~, lipids, h umic subsfances
are formed fiom inorganic compound on
decomposition.
organi compound such as carpon,·
carbon dioxide, water, suJphur, nitrates,
phosphates, and-ions of v_arious;neta]s are
essential fot: organisms to survive.
~£1 1 e a d a tihtde
Latitude has a strong influence on an area's
emperatur~ resulting i~ change of climates such
as polar., tropical, and temperate_'These climates
determine different natural biomes.
From seale;;eJto highe t peaks, wild life is
influenced by altitude. As the altitude increases,
he air becomes colder and drier, affecting wild life
accordingly.
2. Biotic Components
.
Biotic -components include living organisms
comprising plants" animals and microbes and are
classified accordingto their fun~tiqnal attributes into
) 'on um r I t rotr ph uJ hct i oh
(other nou.rishing)
onsumers are incapableofproducing th ir wn
food (photosynthes·s).
~ They depend on organic food derived from
__ .m1ts, animals or both.
~ Consumers can be divided into two broad
groups namely micro and macro consumers.
(i) Macro consumers
~ They feed on plants or animals·or both and are
categorised on the .basis of th~ir food sources.
~ Herbivores are primary consumers which feed
mainly on plants e.g. cow., rabbit.
);> Secondary consumers feed on pdrnary
· consumers e.g. wolves.
);> Carnivores which feed on secondary consumers
are ca1Jed tertiary consumers e.g. lions which
can eat wolves.
);> 011ll1iY9.~~? .i:l:r~.~~g~isms which consume both
p~an san-d animals e.g. man.
Ci) icro consumers - Saprotrophs (deco p sers
or osmotrophs)
);> They are bacteri.u anctfungi-whit:h obtain energy
and nutrients by decomposing dead organic
substances (detritus) of plant and animal origin.
);> The products of decomposition such as inorganic
nutrients which are released in the ecosystem are
reused by producers and thus recycled. .
...-~ ... Earthworm and certain soil organisms (such as
nematodes, and arthropods) are detritus feeders
and help in the decomposition oforganicmatter
and are called detrivores.
C~~ssification,of Eco-system:
producers and consumers. - ----- ·-- - - - -- - -
___ .____Natural.Ecosystem ·
I •
a rimary producers - Autot.tophs (self-
n · • • g)
,
rimary producers are basically green plants
r-..+.;·r.. bacteria and algae).
the ise carbohydrate from simple
•Dr.tDI* rawmaterials like carbon dioxide and
pr en e ofsunlight by the process
PllmiD&lmtlnesis for therns Jves" and supply
r on-produ rs.
••Terrestrial
~
• Forests
• Grasslands
• Deserts
~-················ .Aquftic·
• Fresh Vv t r
• . Saline -Vat rs
• .Marine VV ters
The detailed·study .of e sy. h'm will b d !t.;_.
th ~ubs u >nt ch. pt rs. •
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HAPTE - 1
ECOLOGY
r·.2. ~i':fVIRONMENTgy is asci ntific study of the reciprocal
lationship_bet:Ween organisms (includiDg
microb s, plants, animals, mali) with _Evexyt~gthatsurroundsoraffectsanorganism
• · vironm ·nt. It dea)s with .the.ways in whi~ _4ur~ng tts hfe ti:me is collectively known as.its
anis:ms are moulded by their environment, how · .env)ro~e~t whi~ .comprises both living (biotic)
they make use of environmental resources including. ·.and n.onhvmg (abwtic) components.
energy flow and m ·neraJ cycling. · ·· All organisms(fromvii-us to man) areobligatorily
The term ecology was coined only as ]a teas 1868. dep~ndent on the en ironment for food, energy
h been
water, oxygen_. shelter and for other nee s '
lt as derived from two Greek words namel~ · · ·
· · ·m anin me or pla e to live in and 'logos'. The e iro men is defined as ' t e su["l o a
meaning study. Litera~'y it is the study of the home of li ing, non- i:ing comp onents; influence an '
ofnature. . .ev~nts,. su~<?unding an organism.
Ecology is defined ''as a scientific study of the
relationshi of the Jiving organisms ""lith each other
and with their environment."
. .
1.1.•HISTOR~- OF ECOLOGY
The roots of ecology lie in Natural History,
which is as o]d as human civilization itself. Since
ez : history, man has indulged in ecoJogy in a
practical sort of way, knowingly and unknowingly.
In primitive societies.every individual was required
to have an intimate knowledge of.his environment
for theirsurvival; i.e., about the forces of nature and
of plants and animal~ around him.
Our ancient Indian texts have references to
ecologica) principles. The classical texts of the
_Y~ic. period such as_the Vedas, t}}e Samhitas, the
Brahmanas and the Aranyakas-Upanish~ds contain
many re~ces to ecological concep~s. ..
1be Indian treatise on medicine,. the .Caraka-
Samhita and the surgical text Susruta-Samhi't~,
s~w that people during this period had a good
U.derstanding of plant and animal ecology. ·
These texts contaii) dassification of animals on
thebasisof habit and habitat, land in terms of nature
of soil, climate and vegetation; and-description of
pWts typical to various JocaJities. Carai<a- Samhita
· · fnrmn · n that air, land, W;)tP.r and 5<'flSOn
CWiDEns b]e for 11fe and thnt po1Juted air and
injurjous for health.
·1.2.· .·· C n ee . f e ·~ro e
·The re1ationship and interaction behveen
organism _and envi~onrnent are highly complex.
N? _organism. c~ hve alone without iJ!teracting
'-nlh o tJ- e~ organlSrns. So each organism has other
9rganisms as a part of its environment. Each and
everyJ;hing vvith which we interact or which V.Teneed
for ur sustenance forn s our e vironmenl...
The environment is not static. Both biotic and
abio:ic factors are in a flux and keeps changing
contlnuouslv..r
. - .
ComP.onents of Environ~ent
.Abiotic Biotic
'Energy Green.plantS
Radiation Non-green plants
Temperature & heat flow D~composers
"later Parasites
Atrnosp~erjc gases and wind Symbionts.
Fire
.Gravity
Animals
Man
Topography
Soil . :
Geologic substratum· .
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ir nt t f
pul ti js .group of ory,ani. .rn~ lly of
lh same sp des, crupying hn urm
" a sp cific thne.
· I bi tic nvir nm nt consists of microscopic
all d pl fl~8ft es weli as aquatic
nt and anim ls and decomposers.
nt mal environment of fish
It is enclosed by the uter body surface.
~ The internal envir nment is relatively stable as
compared to the external environment.
~ However, it is not absolutely constant. Injury,
:1 e s or e. ces ive s tress upsets the internal
·ro· e t.
· ~ For e.xample, ·fa marine fish is transferred to a
frE~ 1 'ater environn1ent, it ·il not be able to
1. 0 LS SAT IO S
TheJTiain levels of organisation of ecology are six
and are·as fo lov s.
?.1. Jndj "d
• Organism is an individual living }?eing thathaS
abilitytoact r function independently. It maybe
~ animal, ba t =-rium, fungi, etc. It is a body made
r gans, organelles, or other parts that ~.~·ork
e variou! prr Cf'. ·• ~s of1if~.
Population growth rat is th percenta c
variation between the number of in dividuals :apopulation at two different times. Therefore the
population growth rate can be p ositive or negative.
. The m_nin f~ctor: thut make pQptllation grow are
b.iJttl and 1IDm1gration. The main factors that make
po~ulation decrease are death and emigration.
The main limiting factors for the growth of a
population a~e abiotic and biotic componentS.
Populatio~ de!lsity is the relation between the
number of ind_ividua]s of a popul ation and the area
they occupy.
1.3.3. Community
If we lo_ok around ourself, we will notice that
population o f plants and animais seldom ocarr by
themselves. The reason ior this js quite obvious.
Jn order t~ survive, individuals of any one species
depen~ on indi iduars of ·fferent species ·i h
which they active]y interact in several ways.
For eg: Animals require plants for food and trees
for shelter. PJ_an ts· require an.imais for poUination,
seed dispersal, and soil microorganism to facilitate
nutrient supply.
Communities in most instances are named after
the dominant plant fonn (species).
For example: A grass land community is
dominated by grasses, though_it m ay contain herbs,
shrubs, and trees, alongwith associated animals of
different _species. ·
A commu nity is not fixed or rigid; communities
may be large or _small.
Types of Community
On the basis oi size and d gree of relative
independence communities n'lny be divided into
two types: •
-
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If
I

re
ter
~~:-
J<."• ·
m 'lh orgCliW;ms whic ur · .
1, bundantly in thi~ 7.0n "r> ,., n_man! ,..r 1 : >. t
1 1 't·. 1 'n a c. c ..p · r;
n t 1 t rres na ceo ystl!m§eClg effe . .
11
• ·
i n f f , fu I and fibr applicable to birds. 1 sp eta Y
f h It rand building materials ;..
. l'Or example the density of birds 1
·
9
g t .
ti n fair and wat r h · d h hi f rea er m
t e mtxe a tat o the ecotone between th. f t
i.fi tion and d composition of wastes and the deserl e ores
ta ili:lati and moderation ofthe Earth'sclimate
Niche·> d ration f floods, droughts, temperature
·tr m sand the forces of wind. A ~~c~e is the uniq2te funciional role or place of
:> - Gl'ttt!f tionand rene~alofsoil fertility, including:v::---,aro-.~~p~e_aes ~ an ecosystem. It is a description of all ..
nutri nt cycling. the biOlogtcaJ, phys1cal and chemical factors that a
~ Pollination of ·plants, including many crops species needs tosurvive, stay healthy and reproduce.
Control of pests.and dise~ses A niche is unique for a species, which means no ·
:> Maintenance of genetic resources as key inputs two species have exact identical niches. Niche plays
to crop varieties and livestock breeds, medicines, an important role in conservation of organisms.
and other products 1f we have to conserve species in its na tive
)> Cultural and aesthetic benefits habitat we shquld have knowledge about the niche
Ecotone requiremen~ of the species and should ensure that
all requirements f ~ts rJd-e are fulfilled.Ecoton is a zone of junction bet-ween h vo or
more di erse ecosvstems. For e.g. the mangrove Types of Niche
forests represent'an ecotone between marine J. Habitat niche- where it ]jves
an terres ria e os),stem. Other examples are - 2. Food niche-what is eats or de:omposes & what
gra'ssland, estuary and river bank species j cc . e es . 7
·~.1
- - - -- --· Ecotone- --- -- ·
Characteristics of Ecotone
> It may be very narrow-or'<luite wide.
);> It has the conditions intennediate to the adJacent
ecosystems. Hence it is a zone of tension. · ·
> It is linear as jt shows progre.ssive increase in
species compositionofoneincoming community
and-a simultaneous decrease in species of the.
other ouf going adjoining community.
A well developed ecotones contain some
organisms which.are entiz!!ly different from that
of the adjoining comrn~nities.
,. So l:t ·IH<: • tl c numLer of sp il:s nd tl
population d nsity of some of the _species. is
much greater in thiszonethan either commuruty,
Thi -1 all d edg effect.
3. Reproductiveniche-how and whenit reproduces.
4. Physical & chemkai n ·che - temperature, land
shape, land slOJ-te, humidity 8yother requirement.
1.3.5. B~ome
The terrestrial oart of the iosoh ere is divisible
into enormous regions called biomes, which are
characterized, by climate, vegetation, animal life and
general so.i] type.
No two biomes are alike. The climate determines
the boundaries of a biome and abundance of plants
and animals found in each. one of them. The most
important climatic factors are temperature and
precipitation.
COLD
..
WARM
NW~~-----------------------
BJQJVIE Distribution b s 1on mp ratur
• and Precipitation
~------ ----.---- _______.....
------------------------------------·------~--~-------·-------------------~----~--..
-

4
5
6
7
Toi
Temperate
Deciduous
Forest
Tropical
forest • ·
Savannah
rain
Grassland _ •
ic
una
Devoid of trees ·except stnnted shrubs in the
~outhem rart of tundra biome, ground flora
mcludes lichen, mosses and sedges.
The typical a~als are reindeer, arctic fox,
polar bear, snowy owl, lemming, arctic hare
pta~igan.Reptiles and amphibians are almos~
absent.
Northern Ell!'ope, AS!.~Bn&~-+>The dommatigg vegetation is conifero~s
North America. Moderate evergreen·mosUy spruce, with some pine afid
temperatur~ than tundra. firs. ·
Also known as boreal forest. The f~una co~sists of small seed ·eating birds,
hawks, furbearing carnivores, little mink, elks,
puma, Siberian tiger, wolverine, wolves etc.
Extends over Central and J1te flora includes trees like beech, oak, maple
Southern Europe~ Eastern and cherry.
N·orth America, 'Vestern Most animals are the familiar vertebrates and
China, Japan, New Zealand invertebrates.
etc. Moderate average
temperature and abundant
rainfall. These are generally
t h e ~ o s t p r o d u c.t.Lv e
~ gr i cu ltura l are as of h e
...earth
Tropical areas in the
equatorial regio:ns, which
is abound vvith Jde.
Temperature and_ rainfall
high. . - - ~·· .
- -----··:..:..:....:..:.::.:.:;;.: ·..::...:..·_· · ...
Tropical rainforest covers about 7o/o of the
earth's surface & 40% of the world's plant and
animal species. Multiple storey ofbroad-leafed
e·v~rgreen tree species are in abundance. Most
animals and epiphytic plants are concentrated
in the canopy_or tree top zones.
Tropical region: Savannah Grasses with scattered tree~ and fire resisting
is most extensive in Africa. - thomy shrubs. ······· ····
North America, Ukraine,
etc. Dominated by grasses.
Temperate conditions with
rath r low rainfall.
The fauna include a great diversity of grazers·
and browsers such as antelopes, buffaloes,
zebras, elephants and rhinoceros; the carnivores
include liof cheetah, hyena; and mongoose,
and many roden.Wt.- -- .·· ----·- -- ·-·----"-
Grasses dominate the vegetation. The fauna
include large herbivores li~e bison, antelope,
cattle, rodents, prairie dog, wolves, and a rich
and diverse array of ground nesting bird.
,
Continental interiors with The flora is drought resistance vegetation
very low and sporadic such as cactus, euphorbias, sag brush. Faun :
rainfall with low humidity. Reptil s, M mm ls and birds.
The days ar very h t but
mghts a cold.
.

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1.
2.
3.
m ; how·cvcr.
li zon s, with regions
d anim Hfe.The major
n the v rious aquatic zones are
, I v ls of dissolved nutrients, ~rater
th f sunlight penetratipn.
quatic
ccosyst m
Fresh Water
Ecosystem
Characteristics
Fresh water ecosystem
are dassified as ]otic
(moving.water) or lentic
(still or stagnant water).
Lotic w.ater system
includes freshwater
s fie am·s, springs;
rivulets, creeks, brooks,
and rivers. Lentic water
bodies include pools,
ponds, some swamps,
bogsandlakes.They vary
considerably in physical,
c
. .3.6. Biosp1tere::-----_::·:-~~~~!.
Biosphere is a part of th th _
. B' . e ear wher lif .
~XlSt. ,l?sphere represents a highl r. e e can
Jnteracting zone comprisi~g f Y mtegrated and
hydrosphere (water) and litho~ hatmo(lsphere (air),
. p ere and).
It IS a narrow layer around th f
th lf . . e sur ace of the
ear I . th ~~ VlS~alise the earth _to be the size of an
app e e Iosphere would be as thick as its skin.
Life in the biosphere is ~btifiafl!ll betWeen 200
metres {660 feet) below the surface of the ocean and
about 6,000 metres (20,000 feet) above _sea level.
----<--+~hemicai and biological- --_
char~cteris tics.
1arine
Ecosvstein-'
Estuaries
,
Nearly three:_·quarter
of earth's surface is
covered by ocean
with an average d epth
of 3,750 m and with
salinity_35 ppt, (parts p·er
thousand), about 90 per
cent of which is sodium
chloride.
Coastal bays, river
mouths and tidal
. :m~r~}:les for~ _th~
estuarie-s. ln estuaries,
fresh water from rivers. .. .
meet ocean water and
the two are mixed by
action of tides. Estuaries
· are highly productive
as compared··;o the
d'ac~t river or sea.
•
Biosphere
··---------
Biosphere"is absent at extremes of the orth
and South poles, the highest mountains and the
deepest oceans, since existing hostile conditions
there do not support life. Occasionally spores of
fungi and bacteria d~ occur at great height beyond
8,000 metres, but they are not metabolically acti e,
and hence represent onl 'dormant life.
T-he energy required for the _life within the
bi_osphere co:ines from the sun. The nutrients
-----necessary for iTv'lng-organismscoine from air, water
. and soil. The same chemicals are recycled over and
. over again for life to continue. .
Living organisms are not uniformly distributed
throughoutthe biosphere. Only a few organism live
in the polar -r-egions~ while the·tr pi~~l rain f r s
have an exceedingly rich diversity of plants nd
:mima1s.
•
•

FUNCTIONS OF AN ECOSYSTEM
·.
i .n ofan· system is a broad, vast
llnd mpl t dynamic system. It can be
tudi d under the following three heads.
flovv
utrient cycling (biogeochemical cycles)
Ec ·logical succession orecosystem development
2.1 ENERGY FLOW
En~rgy is the basic fprce responsible for .all
ic a j ities. Tl flow of energy fron1
co ·-u erR L · ,J e e erg_' flow
c · 1 al.
The· study of Trophic level interaction in an
· -·~ E te:r 0}pes an i ea 0 1. • l E ener gy fl ov~·
t.hro.ugh the ecosystem.
2.1.1. ropnic level inte~ction
-T 0ph"~e-Hnteracfon de Js ith how the
r e . e rs of v ecosystem are corJlected based· on
nutritional needs.
1 Autotrophs
11 Heterotrophs Herbivore
(primary consumers)
m He~rotrophs Carnivores
(secondary con u mers)
IV Heterotrophs
Carnivore
(tertiary consumers)
Heterotrophs - .. '
Energy flows through the trophic levels: fr.om
producers to subsequent trophic levels..This"energy
always flows from lower (producer) to higher
erbiv01e, carnivore etc.) trophic level. lt never
flows in the reverse directionthat is from carnivores
o rbivores to producers.
re is a loss of oome energy in the form ·o{
a at each trophic lev 1 o that energy
t I. firr t r J j }·· : np . ~H 1
. -.
•
•
•
As a resun ·there~~ usnmty four or fi""e h hie - .
levels.~d seldo~ more than six as beyondupthat
very ~ttle energy IS left to support any org~m.
Trophic l~vels_are numbered accord~g to'the steps .
an organism IS away from the source of food or
energy, that is the producer.
The trophic level interaction involves three
concepts namely :-
1.· Food Olain
2. Food Web
3. Ecological Pyramids
2.2. OOD CHAl
Organisms in the ecosystem are related tq.each
o er Ll-tro g. !'ee j g nTe anism o tr E s,
i.e. one organism becomes food for the other. A .
~- e ce of org<'rr·sm~ at fee en one ano er, form
a food chain. A food chain starts with prod ucers and
ends With top carnivores. _ ·
The sequence of eaten and being eaten, p roduces
transfer of food energy and it is knuvvn as food chain.
The plant converts so]ar energy into protoplasm by
p otosynthesis. ·-- ·- - ·-
Small herbivores consume the vegetable
matter and convert them into animal matter. These
.herbivores are eaten by large carnivores:
----------
1·.:
., ·,
·l..
··.

-
rt d ins hav
rs whi :h start th food chain,utilising
as theirfood, constitute thegrazing
:1 d1ain b gin. from green plants at .
rimary consumer is herbivore.
Grazing Food Chain
For example, In terestriat-ecosystem, grass is
ea en up by caterpillar, which is eaten by lizard and
Jizard is eaten_by snake. .
~l ..-:.qu~tic tcosystezn pry to Janktons {primary
p..oducers) is eaten by zoo planktons which is ~aten
by fishes and fishes are eaten by pelicans.
ii. Detritus food chain
- . . -
'The food chain starts from dead organic matter
ci decaying animals and plant bodies to the mlcrcr
g and U n to detritus feeding organism ~ed
·r an to ot er prPch-Itor~ .
, ot r f' nf f Tl('f y
ihl f od chaiii
matt i or d·tritu .
-----·--·~UN .TIONS OF
- - ANEosys ·M·
- two food ch ins are linked - -.-.-. ....:_:..::.:.:.:._:...
$Our~ for d tritu food .h .· . .-The lnltial n rgy
• , C <Hn lS th ,
and dead organic matter fro th ~~ te mntc j<l
. m e grazmg food chain
2.3. FOOl:> WEB . .
A food chain represe~ts orJ · .. . .· . .
or energy flow through Yonepartofthe food
an ecosystem and im· li
~imple, isola'ted relationship, which s~)do ~- ~sa
m the ecosystems. . m occurs
An e~osyst~m ~ay consist Ofsevefalinterr~lated
food chams. More typ. icallv the sam f d . ·• · J' e oo resource
lS part of ~ore than one Chain, especially when that
resource ~sat the lower trophic levels. ··
uA food web illustrates, all possjble transfers of
energy and nutrients among the organisms in an
ecosystem, whereas a food chain traces:only one
pathway of the food". ,._ ···
If any of the intermediate food chain is removed, ·
the succeeding Hnks of the ch?in will be affected
largely. The..food web provides more than one_
alternative for food to most of the organisms in an
ecosystem and therefore increases their chance of
survivaJ. · ----------- --.. ---- -.--
For example, grasses_may servefood for rabbit or
grasshopper or goato:r;- cow.Similarly aherbivore may
be food SQurce for many different carnivorous species_.
Also food availability and pre'ferences of food
of the organisms may shift seasonally e:g·: · ·p~ "'a'f .
watermelon in summ~r an_q peaches in the 'Wint r.
Thus there are interconne~ed networks off eding
relaUonships that take the fo~ of food webs.
If any of th in rmedi~te food chain·is r t;n ved,
the ~u cc ling Iinke; ofth :hain.~ · 1be afkded lar ly.
'l ht• f()()d w l> proviJ s mur,· U 1 e • d · l:1
• food to rn s~ of tl1 • >rg ni ·ms in L n n • td
th r for •in 11 •· :1h ar :h. f u

1 glc I
r f n s th b · of the
miv r f nn th tip. Oth r
1 in b twc n.
nsi ts of a number of horizontal
Hie tr phic levels which are_
uenti Ily from primary producer level
rbi 9
[" I runivoreon' 'cltds; -:fhe lt:llglh of
ret>re:;ents the t tal number of individuals
vel in an ~ osystem.
nun;ber, bion~ass and energy of organisms
duall decrease with each step from ~e producer
1 1 to the c nsumer level an~ the- ·diag~ammatic
representation assumes a pyramid:shape..
T e LO] gic;:~l pyr n i s are of three categories.
1. P)-ram·d of numbers,
Pyramid f biomass.. and
)> · 3. Pyramid of energy or productivity.
)Tami of .. urn ers.
11tis deals with the relationship b~tween the
.1'...:. ~ • _ ; t-rim<:.I) t' 1::: t:· cers ·d - S'.JJJ us of
different levels. It is a graphic represen~~tion of the
, • ... . j, : . ~ t.r i1 · · ·· ue:.ls cf ·i(ertr s_p:cie::;,
be onging to each trophic level in an ecosystem.
Depending upon the size and bjomass, the
p_· a id of numbers may not always be upright,
and may even be completely inverted.
z.. y:-amid of l1 1m ers- -prigh•
;> In this pyramid, the number of individuals is
decreased hom lower level to higher trophiclevel.
~ This type of pyramid can pe seen in grassland
ecosystem.
•
•
•
•
-
xt high r tr phic l _v
n m r- h ~bivor ( ampl grasshopper).
> Til individ.u 1 numb r f grn!:shoppcr i~ less
than thnt of grass. The n x "ncrgy 1 v 1is
primary carnivore (example - rat).. ·
> The number of rats are less than grasshopper
because, they feed on gras~hopper. The nex;
higher· trophic level is secondary carnivore
(example -snakes). They feed on rats.
. )> The next higher trophic level is the top c<lrnivore.
(Ex.Hawk). ..
)> .. With ea.ch higher trophic level, the number of
indiviaual decreases.
(b) Pyramid of numbers - inverted
)> In this pyramid, the number of individuals is
increased from lower level to higher trophlc
level.
.. .. '
Hyper-p;or~ e' ·.:::··.-· . ..· ---..-~--~-~~~~~-
> A count in a forest would have a small numberof-- ---
large producers, for e.g. few number ofbigtrees.
)> This is because the tree (Primary producer)being
few in number and ·would repr~sent the base
of the pyramid and the dependent herbivores
(Example- Birds) in the next higher trophic level
and jt is followed by parasites·in thenexttmphlc
leveL Hyper parasites being at hlgher trophic
level represen~ higher fu number.
)> And the resulting pyramid is in inverted f>hape.
A pyramid of nu~bers does not take into.
~ccount the fact that the si:t.t:: of rgani msbeing
(' tf>d in c>ach trophic lP 't~l C;> '"n'
•
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.. -
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,-.. 1' ..· ~
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-
r t rcome the shortcomings of
f nwnber , the pyramid ofbiomass is used.
rr ch individuals in each trophiclevel are
i instead of b ing counted. 1bis give$ us a
n"U"'~n'l·d f biomass, i.e., the total dry weight of an
anisms at each trophic level at aparticular time~
· Pyramid of biomass is usually.determined by
col1ecting all organisms occupying each trophic level
separately and measuring their ,dry weight. This.
overcomes the size difference problem because all'
.kin s of org"anisn1s ~t a trophic level are weighed.
Biomass is measure~ in glm2.
(a) Upward pyramid
For most ecosystems. on land, L'"le pyramid of
1 ma. , has a ;:n e ba. e oJ prjmary producer with
a ~maller trophic level perched bn top.
Pmnory Ccmtvorf!
Producers
Upright Pyramid of Biomass
The biomass of producers (autotrophs) is at the
maximum.. The biomass of next trophic level i.e
primary .consumers is less than. the producers. · Th~
biomass of next high_er trophic level i.e secondary
consumers i~ less than the primary consumers. The
top, high uuphjc le. elhas vtry less amount ofbiomass.
•
. .
..
In cont~ast, in many aqua'tk-:-eco.,._
f b • ~stern~ the
o 10mass may assume an m· J t d .f,
. ver e orm.
...-. .,..~
This is because the producers are tiny
phytoplanktons that grow ~d .z:eproduc~ rapidly.
· ere, he p ramid of b·omass has a srna ase,
with th~ consumer biomass at _any ·instant actually
ex ~ced ing ti1e p roducet biv.:J:ass anct--the-pyrarni<Y- ·:..._:·_..:...··
assumes in~erted shape.
2.4.3. Pyramid of Energy
To compare the functional roles 6£ the trophic
levels in an ecosystem, an energy pyramid is most
su j t~ble. An energy pyram·d, reflecls t e la. ·s of
thermodynamics, with conversion of solar energy
to_chem.ic:al energy and he·at energy at each trophic
· level and with loss of energy being depicted at each
transfer to another trophiclevel. Henc~ the pyramid
is always upward, with a Jar-ge energy.hase at the
bottom.
Let us explain this with an example. Suppose·an
ecosystem receives 1000 calories-of-light enetgy-rn-a-- ---
given day_Most of the energy is not absorbed; some
··is·reflected back to space; of the energy absorbed
only a small portion is utilised by green plants, out
of whkh the plant use~ up some for respiration and
f the 1000 calories, the~efore only 100 cjl}ories are
stored as energy rich materials:
--

Pyramid of energy
'.V suppose an animal, say a deer, eats the plant
containing100 cal offood energy. The deer usessome of
·u rits "rn etabo ~ . and stQr s only 10 cal as food
.. on at eats the deer gets an even smaller
amount of energy. Thus--usable energy decreases
1 sunJight t produ er t -n eroi ·ore to cam.i ore.
Therefore, the energy pyramid will always beupright.
Energy pyramid concept helps tc) explain the
phen menon of bio og)cal magnification-the tenancy
or OY. c ~ ~tances o · crease i co ce ation
progressively at higher levels of the food chain.
2.5 POLLUTA TS Al D TR PH C
LEVEL
Po1lutants espedaJ!y n eg a a Je o es mo e
thro gh t e Yarious trophic evels in an ecosystem.
Nondegradabale pollutants mean materials,
hich cannot be metzbolized by the livingorgani ms.
Example: chlorinated hydro~arbons.
We ~re concerned about these phenomena
because, ogether hey enable even small
concentrations of chemicals in the environment
to find their way into org_arusins in high enough
dosages to -cause problems.
•
1ovement of these pollutants involves two main
processes:
Bioaccumulation..
Biornagnification.
2 .1. Bioaccn.mulation
lt el rs to how pollutants cntet a·food chain.
n ioaccumulation there is an increase in
tt oiapoJJutant fr m th nvirorun nt
r ani min ' f od f'hain.
-
Biomagnific
»- Biomagnification r f •rs to th t d
. rnJlutantstocon (>nfrilt a tJpym n frn(y Of
. ov rn n
trophic 1 vel to th n x . ·
);:- Thus in biomagnification ther 1·s . . •. an mer as ln
co[~dcentr~tion of a pollutant from one link in·a
oo cham to anoth r.
Biomagnification
-
In rder for biomngn ifica =o o o ui, he
pollutant t:JlUSt be: long-lived, mobile,soluble in fats,
biologically active.
If a pollutant is short-lived, ]t will be broken
down ~clore_ it can become dangerous. If it is not
moJ:>ile, it will st~y in one p lace and is unlikely to be
taken up by orga.Jiism~. If the pollutant is soluble in
water, it will be excreted by the organi m . Pollutants
that dissolve mfats, however, may be retained for
a long time.
It is traditional to measure the amount of
. pollutants.in fatty tissues of organisms such as
fish. In mammals, we ofte test the n · r tl
y fern es, ince t e n1i ~ s o• of fat i1 i nre
often more.susc ptible to damage fr rri t ins
(poisons). If~ p Uutant is not activ bi 1 ally, it
may biomagnify, but we really don't vorry ut it
inu , since it probabl w n't cnn , y r bl m
~xarn 1 ; DT.
-

-
BioticInteraction
s..No..
. Species 2Type Spices 1
J..._ Mutualism .. (+) (+)
. Commensalism .(+) . . (0) ..
3. Competition (-) (-)
. Predation. (+) (-}
5. Paras.l~ism (+) (-)
6. A.mensalisni (-) (0)
7. Neutralism (0) (0)
(+) Benefited . . (-) Hanned
(0). T,;:• ...er B- 1ef.t ·d c: .c. n e .
2.6.1. Types of b~o~c intera~on
r .l.a a 'sm: o · ,speci~s be efi .
T: Y3 . Je: ·in -poll" a tio m u tua sms, e
pollinator gets -food (pollen, nectar), and the
plant has its poJ}en transferred to other flowers
or cress-fertilization (~eprod uction).
r Commensalism: one species benefits, the other
1s unaffected.
Example: cow dung provides food and shelter.
to dung beetles. The beetles have no effect on
the-cows.. . ..
> Competition: both species are harmed by the
interaction.
Exarr.ple: if h'O .•pedes eat the same food, and
there isn'tenough for both,both may have access
to Jess food than theywould if alone. They both
suffer a shortage of food
> Predation and parasitism: one species benefits,
the other is harmed. · . .
Example : predation- one fish kills and eats
arasitism: tick gains benefit py suck]n . blood;·
t is harmed'by losing blood.
AIIRCJIIAI m :Onespecies is harmed, the other
aHected.
shades a small plant,
of the smalJ plant. ·The
1 rg : t1 (·.
fit or harm
r
1 t rsp
NCTIONS
Y T M ·•
• t ra tions, the CQsts and ben fits . d
b cl
expen nc
y efl 1 Ra~er are. ex_actly th e same s that
they su~ to zero. It is not.deai how often this
happensmnature. Neutralism is alsosom ·ti.
d
. .b d h e m s
esc:1 : as~~ e relati<:>nship between two .
speoes inhabl~g the same space and using the
same resources, but that have no effet.--t on each
othe;- _In !his _case, one could argue that they
aren t mteracting at alL
2.7. BIOGEo c·HEMICAL cYCLE. . , . . .
The living world de·pends upon the energy .
f.low and the hutdents circulation that occurs
through ecosyst~m. Both influence the abundance
of organisms, the metabolic ra~e at which they live,
and th,~ e<:>mplexity of the ecosystem. ·
Energy flows through ecosystems enabling the
organisms to perform various kinds of w ork and
this energy is ~timately lost as heat fore er in tenns
of the usefulness-of the system. On the other h and,
nutrients of food matter never get used up. They can .
·..,e re ·-yc e rtgai, arid -g2in indefinitely.
For e.g. when we breath e we ~ay be inhalin.g~--
sever al .million atoms of elem ents that may h ave
•been inhaled by our ancestors or other organisms.
C a rbon, hydrogen, oxygen , nit rogen an d
phosphorus as elements and compounds make u p
97%_9f the mass of our bodies and ar.e more than
9 ~o of the ma~s of all li ·ing organisms. ln addition
to these about 15 to 25 other elements are n eeded in
some form for the survival and go_Qg_heaJth .of plants
and animals. · .
These elements or ririneral nutrients are always
in circulation moving from non-living t<? Hving
and then back to the non-living con1ponenfs of the
ecosystem in a more or less circular fashion. TIUs
circular fashion is known as biogeochemiCal cycling
(bioj o,; living; geo for atmosphere).
2.7.1. Nutrient Cycling
The.nutrient cycle is a concept that describes
how nutrient;S move from the physical environm ent
to th e li ing rganisffi:S,.and subs u 1 tly recy 1
back to the phY.,sical environment.
This movement of nutrients fr o m th
enviro:unent into plants and animals and again
back to th environment is ess ntial for life and it is
th vit' l fun ti n ofthf> ec l ~v of anv reoion. In
p rtiru' .r nvironment, t n1aint lJl .it · ~~ u
a su. ta· ed mann r, the·Imtri nt ·I n u ;t
ala d a d st bl .
'l
...

OECOMt~
f ungl nnd _be;ttt'lll
Nutrient cycling_
son.
1umu.! and miMrols. :. . .
T'_rpes of utr· ent Cycfe
}> Based on the replacement period a nutrient cycle
is rt!ferred to as Perfect or Imperfect cycle.
~-
A perfect nutrient cycle is one in which nutrients
are replaced as fast as they are utilised. Most
gasec s cy cles are generally considered as
perfect cycles.
In contrast sedilnentary cycles are considered
·relatively imperfect, as some nutrients are lost
from the cycle and getlocked into sediments and
so become unavaila.ble for immedi_ate cycling.
Based on the nature of the reservoir, there
are two types of cycles namely Gaseous and
sedimentary cycle . .. --
eou Cvc1e - where the reservoir is the
phere'or the hydrosphere, and ·.
,._.......·..... entary Cycle- where the reservoir is the
·•.ru .
•
2.7.2.
L t u fir t study som f th rn . t iUport n
g s us cyd s; na~ely- wat ' orb nan nitr g~n.
(a) Water Cycle (Hydrologi )
Water as ~ important ecological
factor detennmes the struchue a d
fu . n
nchon of the ecosystem. Cycling of
all other nutrients is also dependent
upon water as it provides their
transportation during the vad~us
steps. It acts as a solvent medium for
their ~take.ofnutrients b_y·or_g_anisms.
Thehydr<?logiccycleis the continuousciiculation
of water in the Earth-atmosphere s),stem.which is
driven by solar energy.Water on our plan~t is stored
in major reservoirs like atmosphere, ocearu, lakes,
rivers, soils, glaciers, snowfields, and groundwater.
Water moves from one reservoir lo· another
by the processes of evaporation, transpiration ,
conden.sation, p ecipitaf on, .ep osi i0n, n o , .
infiltra ion, and gro nd1-ater flow.
·· Water Cycle
..L__ _~------~---:----'
(b) Th~ Car~on Cycle
•
Carbon is a minor constituent of·the
atmosphere as compared to oxyge~ ~d
nitrogen. However, without ca:rb. n ~mode
l.i.fi u}dnotexist, ca 1t1s 'l.al r •
the production of carb hyd:at s thr gh_
phot synthesis by pl_an ·. lt 1 th 1 m t
that... dK,>rsallcrgam.r sul.:-·t.m
- d oil t NA(d oxyri
u d
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bn · ~oveslo
p ofphotosynthesis, and then
llft)re;:s ofrespirationand_decomposition
.nr.~-v-·_ matter it returnsback to atmosphere. It
art term cycl .
..
Carbon Cycle
Some carbon also enters a long term cycle. It
accumu ates as u..'l- ecomposed orga.J ·c matter i e
peaty layersof marshy soil or as insoluble carbonates
in bottom sediments of aquatic systems which take
a long time to be released. ..-.
In deep oceans such carbon can remained buried
for millions of years till geological movement may
1ift these tocks abo ·e ~ea ]e';el. These rocks ma} be
exposed to erosion, releasing their carbon dioxide,
carbonatesandbicarbonatesintostreams.and rivers.~
_ Fossil ~such as coals, oil and natural gas etc. are _
organiccompounds that wereburied before they could
bedeoomposedand weresubsequently transformed by
tiJ.ne and geofogical processes into fossil fUels. Whe-n
they are burned the catbon stored in them is released
ack into tr..!! a ospl cr~ as carbon:dioxide.
e ilrogen Cycle
itrogen is an essential constituent of protein
· a basic building block of all living tis~ue. It
CGDIIIIII.tuft!!& y 16% by weight of all the proteins.
st~lt.: ~ l-'1} uf l ilHJ~t.'J
1 m nt 1 fonn c~ 1 not
t of the Jiving organisrns.
•
Nitrogen fixation on earth is accomplished in
three different ways: · ·
(i) Bymicroorganisms (bacteria and blue-green·algae)
(ii) B · rr.a. - c-in g L. d"uE- t1iz.l T':c-·E.sses 'fe:~:Iizer
•factories) and
(~ii} Toalimited extent by atmospheric phenomen n
such as thunder and lighting
The amount of Nitrogen fixed by man
thro gl- in t:st:rial rocess as far e.·ceeded
the amount fixed by the Natural Cycle. As
a result Nitrogen has become a po11utant
which can disrupt the balance of nitrogen.
ltmay lead to Acid rain, Eutrophication and
Harmful Algal Blooms.
Certain microorganisms are capable of fixing
atmospheric nitrogen into ammonium ions. These
include free living nitrifying bacteria (e.g. aerobic
Azotobacter and ana~r-eb-ic-Clo.sttidium) and
-~ymbiotic rutrifying bacteria living in association
with legumi"nous plants and symbiotic bacteria
living in non leguminous root nodu le p1a ts
( .g. .izobiui · s ">'e I as 1~ e gr e algae
Anabaena, Spirulina):
Ammonium ions can be directly tak n up
as a source of nitrogen by orne plan'ts, or are
oxidized to nitrites.or nitratPs by ·two groups of
specialised bacteria: Nitro om na ba t ria pr m te
traJ fom''' iuH Jt i.l.ll~H • J....
th •nfurther trnn form dint
Nitrob ct •r. ·-
. -.
•
•

li~ of soil nitrates, being highly
r, lost to the 'ystem by being
y by stiff~· e run-off or ground
s n swell as oceans there are special
~ cteria ( .g. ;pseudomonas), which
. . nitrates/nitrites to elemental nitrogen. ·
llu n1tr g n escapes into the atmosphere, thus
mf 1 ting th cycle.
. The ~eriodic thunderstorms convert the gaseous
rutr gen m the atmosphere to ammonia and nitrates
·hi . 1. · _ntu lly reach the earth's surface through
rr l f 1 a n a d then into the soil to be utilized by
Iants.
The main storage for phosphorus is in the earth's
· crust. On land phosphorus is usual1y found in the
form of ~hosphates. By ~e proe~ss-of-~eathering
and eros10n pho~ph a e enter rivers and stre2 ms
·that transport them to the ocean.
·In theocean once-the . os ho sCICC1Jm1 1a t?-~ 0
·con?nental shelves in the form of insoluble deposits.
( ~~ . illi fr-..u r m ons o ye<ns, th e c- u ~ta plates 1i~ e freT.!-. lh e
'
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I.
I
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sea floor and expose the phosphates on land . After
m ore time, weathering ''~ill release them fro rock ·- -
and the cycle's geochemical phase be~s again.
2.7.3. Sedimentary Cycle
Phosphorus;·calcium and magnesium circulate
by means of the sedimentary cycle. Th~ element
involved in the sedimentary cycle normally does
et c_:de through the atmosphere but foJlows a
basic patte~f..flow ihrough erosion, sedimentation,
mountain building, volcanic activity and biological
transport through theexcreta of marinebi!ds~-
(a) Phosphorus Cycle ·
(b} SulphurCyde
The sulphur rese1 :·oir is L'l the soil and sedimeJ ts
where it is locked in organic (coal, oil and peat) and
inorganic deposits (pyrite rock and sulphu r rock) in
th_e formofsulphates, sulphides and organic sulphur.
It is released by weathering of rocks, erosiona1
runoff and decomposition of organic matter and is
carried to terrestrial_and aquatic ecosystems in salt
solution. · · · · · ·
Tilesulp ufcyc1e 1s mostly sedimentary exc~pt
two of its compounds hydrogen sulphide (H2S) and
sulphur dioxide (S02
) add a gaseous component to
Phosphorus plays a central role in aquatic········ its normal sed!mentary cycle.. ..
ecosystems and ater quality. Unlike carbon and Sulphur enters. the atmosphere from se eral
g i xocpriman1y from l1 e atmosphere, sources !ikevolcanic eruptions, combustion of fossil.
- ·---phorus occurs in large am0unts as a ~eral in fuels, from surface ofocean and from gases released
hat rocks and enters the cycle from erosion · l?Y de.composition.Atmospherichydrogen sulprude
g activities.Thisisthe nutrient considered also getsoxidised into sulphur dioxide.Atmo ph ric
Ofexcessive growth of rooted su1phur dioxide is carried back lo th r~rth · fter
· oscopic plants in lakes. . being dissolved in rainwat r as weak u1phuric cid.
•
. .
.J: :·
. ·.,. .
·.. ·...·
'··.

Sulphur Cy~Je
h source, sulph 1
r i1 the form of
e u by r a t and inco porated
trOt: .. 3 ri of me~a rCp OCESSeSin O S 1lphur
b aring ?mino acid which is incorp01;ated in the
roteins of autotroph tissues. It then-passes through
e-g z.j, . g ood am.
. bo nd in r j g 0 sm jc:; carrie
back to the soil, to the bottom of ponds and lakes
and seas through_- excretion and decomposition of
ea organic material.
The Bio-geochemical cycles discussed here
are only a few of the many cycles present in the
eco ystem . Tnese cycle usually do not perate
mdefe:tdent]y bu t interact with E.'ilCh other a some
point or the other.
2.8. SUCCESSION
Succession is a universal process of directional
ar·gc in C;g<:taliun, u an ecologi al time ' 1
Succession oc~rs when a series of co~unities
replace one another due to large scale des~ction
ei r natural or manmade. This process continue~
one community replacing another community,_tmtil
bl , matur community develops.
:, I ·s '- psugrc~s1v~ ~t:!1cs of c l.allg~.::s
t l}, · !>t«Jbli!:.hrn •nt of a relatively stable
omr u ity.
. ~~~ :
··... Tlme· -----~t..-
· Ecological Succession
2.8.1.. Primary Succession
Jn primary succession on a terrestrial site he
new _site is first colonized by a f~w hardy pio eer
species that are often microbes, lichens and mosses.
T e pioneers over a fev,r genera io .s <1 ter:l.e ..abita!
conditions by their.grow th and development.
These new conditions may be conducive to the
estab1ishrnent of ad ditional organisms that may
subsequently arrive at the site. The pioneers through
their death any.decay leave patches oforganic matter
in which small animals can Hve. ·
The organic matter~ produced by these pioneer
species produce organic acids during decomposition
that dissolve and etch lhe substratum releasing
nutrients to the substra_tum. Organic d~bris
accumulates in pockets and crevices, providing soil
m hich seeds can become lodg d and gxow.
As the cmnmtmity of or-ganisms continue to
develop, it becomes more diverse and compe_tition
increases, but at the s ame time new ni h e
opportunities de elopE.-.
The pioneer sp des di nppear as th habi~
, t 1 ditim ~: c <P t;t.. ~.- n d i'J 'o~~iu d l ' F ' :c
• ~ d' lh 1..,.,. mnnt of the·rog- s c.6, It,a . 111 g t o r p en. "
pr ceding c mn unity.
- •
-

-
s i n is the sequentiAl
f i ti ommunities after the
J p rti I d struction of the existing
unity. Am tur or.intermediate community
d troyed by natura) ev*:?nts such as floods,
h~ fires, O!,.storm~r by human intervent!_ons
defoxcstation, agriculture, overgrazing, etc
This abandoned farmland is first invaded by
ha rdy speciesofgrasses ~at can survive inbare, sun-
baked soil. These grasses may be soon joined_by tall
grasses and herbaceous plants. These dominate the
ecosystem for some years along with mice, rabbits, -
insects and seed-eating birds. .
Eventually, some trees come up in this area,
seeds of which may be brought by wind or animals.
0'cr the years, a forest community de_velop s.
Th g an abandoned farmland over.a period .l?~comes
~ n- u·.at 'y trees an is transformed mto a forest
•
•
bet~m prim ry and secondarf
lljlielldfm, th secondary successi n starts n a
,.,.,IP@.nped i1 alieady formed at th ...ite.Thus·
secondary succession isrelatively foster as compared
to primary succession which m ay ftej1 requite
hundreds of years.
2.8.2. Autogenic and Allogenic Succession
· When succession is brought about by living
inhabitantsofthatcommunityitself, the pioa?Ssisc:alled
au~c su~cession, while chnnge brought aboutby
outm'ae forces is known as allogenic Succession._____ _
2.8.3. Autotrophic a~d Heterotrophic
~cr~~oo •
Succession in which, initially the green plants
are much greater is ~antity is known as autotrpphi~
·Succession; and the ones in whi¢ the heterotrophs are
greaterinquantity isknownasheterotrophicsuccession.
Succession would occur faster in area e~sting
in the middle of the large continen t. This is because,
here all propagules or seeds of plants b elongjngto
the different seres would reach much faster, establish
and ultimately result in climax community.
_..·::.· :: · ·.·.:. · · · ::.::·.· · · · · · ····
•
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.._....
.....
.-
CHAPTER-3
TERRESTRIAL ECOSYSTEMS
T
he interrelations between organi_sms
and environment on the land constitute
~Terrestrial Ecology". Dl}e to variation in
the topographic features of valleys, mountains arid
sl pes, ertain differences occur. Thesedifferences are
reflected in both the material and biotic diversities.
Altitudinal and Jatitudinal vaFiations cause shh'is and·
differ nces in the climatic patterns. Due to varied
c1i 2 e, the plant and an·mal life existing in different
t r cstri 1· xeas ary ·.vhich result in differentiation
ofecosystem as segments within the large biosphere.
The mo~t ·m portant Hm·ting·factors of the terrestriaJ
. ecosystems are moisture and temperature.
The v;ord hmdra means a "barren land" since
U1ey are found where environmental conditions are
.very severe. There are two types of hllldra- arctic
<!.fld a~pme·.
> Di5tribution: Arctic tundra extends as a
continuous belt below the polar ice cap and
above the tree line in the northern hemisphere. It
occupies the northern fringe of Canada, Alaska,
European ~ussia, Siberia and island group of
Arctic Ocean. On the south pole, tundra is very
small since most of it is covered by ocean.
Alpine tundra occurs at high mountains above
the tree line:-Sincemountains ·are7ou_n_d af"all -
latitudes therefore-alpine tundra shows day and
night temperature variations. .
) Flora and fauna: Typical vegetation o(arctic
tundra is cotton grass, sedges, dwarf heath,
~illows~ birches and lid1ens. Animals of tundra
are reindeer, musk ox, arctic hare~ caribo~·s,
lemmings and squirrel.
Most of themhave1ong life e.g. Salix arctica (i.e)
arctic willow has a life.sp~ of 150 to 300years. They
are protectPd from chi11nes~ by the presence ofthick
qmde and epic:lermal hair. Mammals of the tundra
region have large body size and small tail and ear
~ to avoid the loss of heat from the surface. The body
•
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is covered wilh fur for insulation. Insectshave short
life cycles which are completed during _favourable
p_eriod of the year.
3.2. FOREST ECOSYSTEM
. .
The forest ecosystem includes a complex
assemblage of different kinds of biotic communities.
Optimum conditions such as temperatureand grolll!d .
moisture are responsible for thE esl List e of
forest communities.
The.natur.e.of soil, dimate and local topbgraphy
determine the distribution of trees an their
abundance in the forest vegetation. Forests mav-·be· .~ .
evergreen or deciduous. They are distinguished on ·
the 9asis of leaf into broad-leafed or needle leafed ..
coniferous forests in the case of temperate areas.
The forest ecosvstems have been Classified into.r
three major categories: coniferous forest, ter.1pera e
forest and tropical forest. All these f rest biomes are
generally arranged on a gradient from north to south
latitude or from high to lower altitude.
3.2.1. Coniferous forest (boreal forest):
~ Cold regions with high rainfall, strong seasonal
climates with long winters and short s-ummers
aie characterised by boreal coniferous f~rest
)> . This is characterised by-evergreen plant species_
such as Spruce, fir and pine trees, etc and by
aJli.mal::; ··ucl1 Js t 1 Jyn: , '·c lf, 1 , !' f ,
porcupin~ squirrel, nnd am1 h.ibi;u5 like Hyla,
Rana, et(! · ·
"1fD·
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