1. Lecture 16 Article
Agriculture Biodiversitya Dilemma inFuture Crop Production
Agriculture
Agriculture dependsonhealthyecosystemstoprovide servicesthatincludenutrientandwaste
recycling,pollinationfrominsects,sedimentcontrol,andcleanwater.Clearingof native vegetation,
some grazingpracticesand inappropriate fertilizeruse have contributedtoadecline inwaterquality,
ecosystemfunctionandinbiodiversity.
Ecosystem
An ecosystemisanatural entity(ora system) withdistinctstructuresandrelationshipsthatinter-link
bioticcommunities(of plants,animalsandmicro-organisms)toeachotherand to theira biotic
environment.The extensionof anecosystemdoesnothave precise limits,butischaracterizedbya
commonoriginor commondynamicprocess.Ecosystemsmake upbignatural systemssuchas
grasslands,mangroves,coral reefsandtropical forests,butalsoagro-ecosystems,whichare highly
dependentonhumanactivitiesfortheirexistence andmaintenance.
Critical Ecosystemsand Pakistan
Under the Global 200, ecosystemshave beenrankedtocarry outconservationthroughcomparative
analysis.Itcoversall habitatsonthe land massesandinthe ocean.The Earth has beendividedinto238
ecoregions,bythe UnitedNation,the National GeographicSocietywithWWF.Outof them5 are in
Pakistan.The Global ecoregionsof Pakistanare:
Rann of Kutch floodedgrasslands
TibetanPlateau
WesternHimalayanTemperate Forests
IndusDeltaEcosystem
5. ArabianSea
About5,500 - 6,000 speciesof vascularplantshave beenrecordedinPakistanincludingbothnative and
introducedspecies.The floraincludedelementsof the 6phytogeographicregions.4monotypicgenera
of floweringplantsandaround400 (7.8%) speciesare endemictoPakistan.
Almost80% of the endemicsare foundinthe northernandwesternmountainsThe KashmirHimalayas
are identifiedasa global centre of plantdiversityandendemism.Familieswithmore than20 recorded
endemicsare Papilionaceae(57species),Compositae (49),Umbelliferae (34),Poaceae (32) and
Brassicaceae (20).
MammalsAround174 mammal specieshave beenreportedinPakistan.Outof these,there are atleast3
endemicspeciesandanumberof endemicandnearendemicsub-species(BiodiversityActionPlanfor
Pakistan,WWF- P, IUCN - P and GoP).

2. 668 birdspecieshave beenrecordedinPakistan.Outof them, 375 were recordedasbreedingBreeding
birdsare a mixture of PalearcticandIndomalayanforms( 1/3rd) and the occurrence of manyspeciesat
one or the other geographical limitsof theirrange showsthe diverseoriginsof the avifauna.The
SuleimanRange,the HinduKush,andthe Himalayasinthe NWFPandAzadKashmircomprise partof the
WesternHimalayanEndemicBirdArea;thisisthe global centre of birdendemism.The IndusValley
wetlandsare the secondareaof endemism.
Reptiles/Amphibians
Around177 species,beingablendof PalearcticandIndomalayanforms.Outof the total 14 speciesof
turtles,90 of lizardsand65 of snakeshave beenreported.While 13speciesare believedtobe endemic.
Beinga semi aridcountry,only22 speciesof amphibianshave beenrecorded,of which9are endemic.
(BiodiversityActionPlanforPakistan,WWF - P, IUCN - P and GoP).Fish/InvertebratesPakistanhas198
native andintroducedfreshwaterfishspecies.The fishfaunaispredominatelysouthAsianandwith
some westAsianandhighAsianelements.Fishspeciesdiversityishighestinthe Indusriverplainsandin
adjacenthill ranges(KirtharRange),andinthe HimalayanfoothillsinHazara,Malakand,Swat and
Peshawar.Diversityislowestinthe mountainzone of the northernmountainsandaridpartsof north-
westBaluchistan.There are 29 endemicspecies.There hasbeenlittle researchonInvertebratesof
Pakistan.About5,000 speciesof invertebrateshave beenrecordedincludinginsects(1,000speciesof
true bugs,400 speciesof butterfliesandmoths,110 species of fliesand49 speciesof termites).Other
includes109 speciesof marine worms,over800 speciesof mollusksand355 speciesof nematodes.
(BiodiversityActionPlanforPakistan,WWF - P, IUCN - P and GoP).
Threats to Biodiversity:
Deforestation:Pricinciplecause of deforestationinPakistanisthe consumptionof fuel woodand
timber.
Grazing:
Rapidlyincreasingdomesticlivestockpopulationisthe directcause of degradationonrangelandsand
forests.
Soil Erosion & Desertification:
Agricultural activitiesandoverstockinghasleadtothe reductionof vegetationcover,resultinginthe
accelerationof bothwindandwatererosion.Dams/Irrigation:The constructionof damsandbarragesin
the Indusbasinto control floodingandstore waterforirrigationhave greatlyincreasedthe amountof
WetlandshabitatinPakistan.Reductioninfreshwaterflow tothe coasthas greatlyincreasedsalinityin
mangrove forests.The mostseriouseffecthasbeenthe consequentconversionof landtoagriculture,
withremoval of extensivetractsof riverine andthornforestsandthe resultingdisappearance fromlarge
areas of the associatedfauna.Salination/waterlogging:Beingaseriousproblemfacedbythe agriculture
sector,pocketsof forestsof the Indusbasincouldbe threatened.Pollution:Pakistanfacesaserious
challenge of growingpollutioninurbanareasand watercourses.Likewise dischargeof sewage and
industrial effluentintoaquaticandmarine ecosystemsisalsoonthe rise.InPakistan's1981 census,415
citieswere classedasurbaninwhichlessthanone thirdof the populationresides,whichisincreasingby
4.4% per annum.Hunting/Fishing:There isastrong traditionof illegalhuntingandsportshuntingin
Pakistan.Thishasresultedinto the declineof birdandmammal species.Agricultural practices:Pakistan
facesdegradationof agro-ecosystemscausedbyirrigation.The agricultural use of pesticidesand

3. fertilisershasrapidlyincreasedinrecentyears.Pesticide use inPakistanhasincreased7foldinquantity
between1981 and 1992.