OCCASSIONALPAPERS ManagingTrans-BoundaryNatureReserves: CaseStudiesonSunderbansMangroveEcosystems SudhaMehndiratta ProgrammeCoordinator ASIA-PACIFIC REGIONAL BUREAU FOR COMMUNICATIONANDINFORMATION UNESCO HOUSE, B-5/29,SafdarjungEnclave, NewDelhi-110029 CoverPage:Shrimpfrycollectionbyusingfinemeshnets, Sunderbans,Bangladesh Thedesignationsemployedandthepresentationofthe materialinthispublicationdonotimplytheexpressionof anyopinionwhatsoeveronthepartofthepublishers concerning,thelegalstatusofanycountryorterritory,orof itsauthorities,orconcerningthefrontiersofanycountryor territory. Theauthorsareresponsibleforthechoiceandthepresentation ofthefactscontainedinthisbookandfortheopinions expressedtherein,whicharenotnecessarilythoseofUnesco anddootcommittheorganisation. Nopartofthisbookmaybereproduced,inanyformwithout permissionfromthepublishersexceptforthequotationof briefpassagesforthepurposeofreview. 02002,UNESCO TABLEOFCONTENTS Preface CaseStudies EcologyandManagementoftheSunderbans MangroveEcosystem,Bangladesh MD.GIASUDDINMIAH& MD.NASIMULBAR1 EcologyandManagementofSunderbans BiosphereReserve,India SANJAYV.DESHMUKH,T.ANANDARAO& AMLiSHCHOUDHURY PageNo. .. . I-11 1-44 45-73 Preface UNESCOthroughitsinitiativeundertheManandtheBiosphere(MAB)Programme hasattemptedtoconceptualizeandtoprovideaframeworkforlookingatecosystems notmerelyasbiophysicalsystems,buttolinkitwiththecloselyinter-linkedhuman dimensions.TheBiosphereReserveconceptprovidesthespatialframeworktolookat thislinkagebetweentheecologicalandsocialdimensions,inthecontextofconservation ofnaturalresourcerichecosystems,aspartofthelandscape. BiosphereReserves/WorldHeritagesites/NatureReservesspreadacrossalarge ecologicalzone,cuttingacrossnationalboundaries,oftenoperatingunderdiversesocio- economicandpoliticalsystems,offeropportunitiesfor:(a)addressingcommonconcerns ofbiodiversityconservationandthelinkedsustainabledevelopmentoflocal#communities; (b)sharing/exchangingknowledgeonsimilarconcernsandchallengesthatoftencut acrossdifferingsocio-politicalandsocio-culturalsystems;and(c)thuscontributetowards abetterunderstandingbetweennationsandpeople,bybuildingastrongerfoundation forregionalcooperation. Thisisthecontextinwhichthewholeissueofmanagementofthetrans-boundary naturereservesofSunderbansshouldbeviewed.ThetwocasestudiesfromtheIndian andtheBangladeshsideofthisuniquemangroveecosystemaretheproductofa sharedcommoneco-culturalheritage,withsimilarchallengesintheareaofnatural resourcemanagementlinkedwithhumandevelopment.Therefore,management solutionscancomethroughawellcoordinatedresearchanddevelopmentalinitiativein theprotectedareasthatstraddlesacrossthenationalboundaries,aspartofacontinuum. Manykeyissueshaveemergedthroughthetwocasestudies.lJnsustainable landusepracticeshaveleadtorapiddeclineinbiodiversity,whichinturnhasleadto erosioninbiodiversityandtraditionalland-usemanagementlinkedtraditionalecological knowledge(TEK)baseofthelocalcommunities.Bothcasestudies,frornBangladesh andIndia,emphasizetheneedtomonitorclosely,variousenvironmentalparameters overtimeandspacetogetabetterunderstandingoftheissuesinvolved.Theultimate messageemergingfromthesestudiesare:(a)thatShrimpcultivationinSunderbans hastobeadaptedandrestrictedtosustainablelevels;(b)sustainableagricultural practiceshavetobeevolvedbasedonthetraditionalknowledgebase,appropriately linkedwiththeformalknowledgesystem.Inaregionalcontextofoverallcoastal-zone management,establishmentofanetworkofmarineprotectedareasdistributedin ecologicallydistinctzonesallalongthecoastwouldbeanimportantstepforpromoting comparativestudiesthatwouldenableustoarriveatmeaningfulgeneralizations,on avarietyofissuessuchasparticipatorymanagementofmangrovesecosystems, sustainableagriculture/shrimpculturepractices,urbanizationandeco-tourism. Thesetwoshort-termstudieswerecommissionedinordertounderstandand evaluatetheimpactofcoastalresourceuseandenvironmentaldegradation,with implicationsforthecoastalcommunitieslivingintheSunderbans,inordertoprovide guidelinesforfacilitatingdecision-makingprocessaswellasecosystemmanagement practices. ItishopedthatthetwocasestudiesdealingwithmanagementissuesofSunderbans mangroveecosystemwouldbeusefulforscientists,administrators,managersandplanners, formakinginformeddecisionsontheconservation,useandmanagementofthisecosystem. ItisapleasureforUNESCOtothankalltheauthorsofthetwopapers,particularly, Prof.Md.GiasuddinMiah,Head,DepartmentofAgroforestryandEnvironment,Bangabandhu SheikhMujiburRahmanAgriculturalUniversity,Salna,Gazipur,Bangladesh,andDr.Sanjay V.Deshmukh,Director(Research),RambhauMhalgiPrabodhini,Thane,India,fortheir commitmentanddedicationinundertakingthisfieldstudy.IwouldalsoliketothankMs. SudhaMehndirattafromUNESCO-NewDelhiOffice,whowasresponsibleforoverallco- ordinationandmanagementofthisprogramme. Prof.M.Tawfik Director,UNESCO,NewDelhi ECOLOGYANDMANAGEMENT OFTHESUNDARBANSMANGROVE ECOSYSTEM-BANGLADESH Md.GiashuddinMiahandMd.NasimulBaril DepartmentofAgroforestry&Environment BangabandhuSheikhMujiburRahmanAgriculturalUniversity, Gazipur,Bangladesh TheSundarbans,locatedinthesouth-westernpartofBangladeshisauniqueaswellasthelargest singlemangroveforestintheworld.TheforestareacomprisespartsofBagerhat,Khulna,andSatkhira districtsofBangladesh.Geographicallytheforestarealiesbetween212730-22030O Northatitudeand8902OO-9000000EastLongitude.ThetotallandareaoftheSundarbansasa wholeisabout6017km2,theBangladeshpartofwhichisaround5800km2.Withatotalareaof 577000ha,thelandmassis401600ha,withwaterbodiesaccountingfor175600ha(Hossainand Acharya,1994).TherestpartliesintheWestBengalStateofIndia.Thetotalmangroveforestarea isaround4.2%ofthetotallandareaofthecountry,thisbeing51%ofthetotalforestarea (CanonizadoandHossain,1998).Itisthemostdiverseandtherichestnaturalresourcein Bangladesh.Beingaverydynamiccomplexsystem,thisfragileecosystemisinadelicatebalance, inter-phasingbetweenlandandwater.Thiswildlifeheritageofthecountryisarichhabitatfor offshorefisheriesandonshoreshrimpcultivation,andrichinforest-basedresources.Thus,itisa majorsourceofgovernmentrevenue,atthesametimemeetingthelivelihoodneedsofthelocal communities.TheSundarbansisrichinfloralaswellasfauna1biodiversity.Atotal334species representing245generaofplantsthriveintheSundarbans(Siddiqui,1998).Asmanyas120 speciesoffish,59speciesofreptiles,over300speciesofbirds,and42speciesofmammalshave beenrecordedintheSundarbans(UNDP/FAOIRDP,1995).TheSundarbansReserveForestand surroundingareashavearichavifaunaandthemostrecentlistofspeciesindicatesthatatleast315 speciesrepresenting48%ofthebirdsknowntooccurinBangladesh,havebeenrecordedhere (IUCN,1994).Regardingitsuniquestructure,scenicbeautyandbiodiversity,UNESCOin1997 declaredthreewildlifesanctuariesoftheSundarbansasWorldHeritageSites. HumandependenceontheSundarbansforestresourcehasalwaysbeenthere.Butinrecentyears populationhasincreasedalot.Currently,around500,000familiesaredependentontheSundarbans fortheirlivelihood.About200,000fishermenarealsodependentonthisforest,,supportingabouta millionhouseholdmembers(CanonizadoandHossain,1998).Withincreasedhumanpressureonthe naturalresources,alongwithothernaturalcatastrophes,thebiodiversityofthisforesthasbeen diminishingatanalarmingrate.Thedegradationprocessstartedinthelaterpartofthenineteenth centurywhenthethenBritishGovernmentdecidedtoclearpartsoftheforestforsettlementand agriculturalactivitiesandithasledtolanduseconversionsimpactingupontheecologyoftheregion, associatedwithlossofbiodiversity.Introductionofmodernricecultivationandshrimpculturehasled toindiscriminateuseofagro-chemicals,andtheresultantpollutionproblems.Decliningforestcover, reductionofsweetwaterflow,increasedsalinity,unplannedembankments,waterpollutionfromindustrial activities,etc.aresomeofthemajorconsequences.However,theconsequencesfromtheseimpacts areyettobeprecised;ourunderstandingoftheecologicalprocessesdeterminingthedynamicsofthis uniqueecosystemfunctioningisstillincomplete. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS 0 Thepresentstudy,therefore,hasthefollowingobjectives: (a)Characterizationofthehistoricaltrendsinland-useintheSundarbansregion; (b)Identifyingrecenttrendsinlanddegradationassociatedwithagricultural/pisciculturalactivities; (c)Formulationofmanagementstrategiesfortheconservationofthenaturalresources,basedon ecological,economicandsocialconsiderations. StudyArea ThreeUpazillasadjacenttotheSundarbansReserveForestunderthreecoastaldistrictswereselected. TheseUpazillaswereMonglaunderBagerhatDistrict,DacopeunderKhulnaDistrict,andShyamnagar underSatkhiraDistrict(Fig.1).IneachUpazillaoneUnionwasselectedforthestudy.Thesewere ChilaUnionunderMonglaUpazilla,SutarkhaliUnionunderDacopeUpazilla,andMunshigonjUnionunder ShyamnagarUpazilla.Again,onevillageundereachUnionwasselected.ThesewereChila,Sutarkhali, andMunshigonjvillageunderChilaUnion,SutarkhaliUnion,andMunshigonjUnion,respectively(Fig.1). ThespecificmapoftheSundarbansReservedForest(SRF)alongwithitspresentspeciescomposition hasbeenshowninFig.2.Itmightbementionedthatthestudyvillageswerelocatedwithinthebuffer/ impactzoneoftheSRF(O-10km),morespecifically,withinO-5kmoftheSRF. ThestudylocationslieunderGangesTidalFloodplainAEZ(AEZNo.13)(Fig.3).Thisregionoccupies anextensiveareaoftidalfloodplainlandinthesouth-westofthecountry.AlmostallpartsofKhulna, Bagerhat,SatkhiraalongwiththeSundarbansReservedForestareincludedunderthisregion.However, smallpatchesofareasrepresentingHighGangesFloodplainwerealsoevident.Thetotalcoverageof thisregionis17066km2withatotallandmassof1706600ha(whenBarisal,Jhalakathi,Pirojpur, Patuakhali,andBargunaareincluded). Soils: GeneralsoiltypesofthestudyareasareinFig.4.ThesoilsofMonglaareentirelyNon-calcareousGrey FloodplainSoils,whereasmostsoilsunderDacopearealsothesameexceptCalcareousDarkGrey FloodplainSoilsatnorthernpartsoftheUpazilla.AconsiderableportionoftheShyamnagarUpazilla representsAcidSulfateSoils,althoughthesurveyareafallsunderNon-calcareousGreyFloodplain Soils.Abriefnoteonthegeneralsoiltypesintheregion(adaptedfromIslamandSaha,1998), particularlywithinthestudyareas(Fig.4)hasbeenprovided. Non-calcareousGreyFloodplainSoils(SalinePhase):Thisgeneralsoiltypeoccupiesthemajor areasoftheGangesTidalFloodplainAEZ.Theorganicmattercontentislow(1.7%)inmostcases. DeficiencyofN is acuteandwidespread.StatusofexchangeableK is almostsatisfactory,consequently K deficiencyislessfrequentlyobserved.RegionalvariationinP statusisalsoremarkable.P deficiency isgenerallyprevalentinSatkhira,Patuakhali,BargunaandBagerhatdistrictswhileinKhulnadistrict supplyofPisalmostsatisfactory.Zincdeficiencyisobservedinallovertheareas.Copper(Cu) deficiencyisalsowidespreadinthecoastalregionsofSatkhira,Khulna,Bagerhat,andotherareas. Borontoxicitysometimesoccursincoastalsalinesoilsbecauseofhighboroncontentofintruding seawater. CalcareousDarkGreyFloodplainSoils:Thetop-soilsarecalcareoushavingpHvaluesrangingfrom 7.2to8.1.Organicmatterisquitevariable(0.95-2.00%).Potassiumcontentsarequitehigh.Thisis duetothepresenceofalargeamountofKbearingmineralsinthesesoils.Nisdeficientinallthe areasunderthissoils.Pisgenerallydeficient,whileSdeficiencyisobservedlessfrequently.Zinc deficiencyisprevalentinallthesoilseriesbecauseofhighpHvalues. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Figure 1: Location of the study areas A CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS 81 --..w___-___--CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Figure3: Agro-ecxMgicaltonehiofBangladesh t I%w.+elM uwm -._1. . . . I I i CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m -. --...- - Figure4:Gsnefalsoiltypesof thsstudyareas ___I--~.-n-_I.;____^, - . - ___.. f I - . . I . - _- . .,__. . . - _. - . . . , - x- - _. - . , - . - I - . _ - ~_~ __. _. . X. ~~~~.^^~.~~-~-___.-,~-.^_I-_.~-l~~^, . . ___ _-___- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Figure5: SoilpHofthestudyareas -.~-_~_~-__~~.~_I~--.~..--._c_--__l--l_---.^_-l_n_l_-^^--x-~---....~--~--..~--~---~~~-- -.__-...^__-._..-~-~.^~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS u CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMSu 89O891589w89@4590 Figure7: Agro-mologicalfyconstrainedareas withinthestudyregion -1-u DeeplyInundatedArea TidalSurgeArea NonConstrainedArea ~_~~-_l__) - . I - xI - - . -~-__p_-____l__ ~~-~~- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS u I Figure8: Availablesoilmoisturein thestudyregion CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m figure9:SalinezoneofBangladesh SalinityCategories (by pm&of total Upellaarea) .1 Non-Saline Sls70% 52> 70% s1 +s2> 60% S2+Slzs60% sl+s3> 60% I s33 60% S2+53> 60% S3+S2 > 60% S2+S4 > 60% S3+54 > 60% AcidSuifateSoils:About0.7millionhaofacidsulfatesoilshavebeenidentifiedinBangladesh. AsignificantproportionofAcidSulfateSoilsexistsinSatkhira,KhulnaandBagerhatdistrictsof GangeticFloodplainareas.Extremeacidity(pH2.9-4.0)developedunderdryconditionsandpossess severaladversesoilconditionsinrespectofsoilfertility.Amongthem,toxicityofsolubleironand aluminumandseveredeficiencyofParequiteremarkable. SoilsofthestudyareaunderMonglaweremostlymoderatelyacidtoneutralhavingapHrange between5.5-7.3(Fig.5).AlthoughDacoperepresentssoilshavingthesamepHrange,however,a considerableportionfallsundermoderatelyalkalinegroup(7.3-8.4). Agro-ecologicalConstraints: Thestudyareasfallmainlyundermediumhighlandcategory(Fig.6).However,inMunshigonj UnionunderShyamnagarpatchesofmediumhighlandswerealsoavailable. Amongtheagro-ecologicalconstraintsthemajoroneis,however,thesusceptibilityoftheregionto moderatetoseveretidalsurges.MajorportionofthethreeUpazillasweretidalsurge-prone(Fig.7). ThestudyareaunderMonglawasentirelytidalsurge-proneareas,whereasSutarkhaliUnionunder DacopeandMunshigonjUnionunderShyamnagarwerepartlyunderseveretidalsurgearea. StatusofsoilmoistureholdingcapacityshowninFig.8suggestfourdifferentsoilmoistureregimes intheregion,rangingfromlow(100-200mm)inShyamnagar(Satkhira),whileiinDacope(Khulna) andMonglamoisturelevelsweremoderate(200-300mm). TheentireregionrepresentsthesalinezoneofBangladesh.Fig9showssalinitycategoriesby percentoftotalUpazillaareas.Amongthestudyareas,DacopeandMonglarepresentstheareas wheresalinitywasinS2category,whichmeantthatover70%oftheUpazillasareaffectedby salinity.Incontrast,ShyamnagarfallsunderS2+S3categorymeaningthatover60%oftheUpazilla isaffectedbysalinityalongwiththedominanceofS2category. -~-___I___. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m DemographyandSocio-Economics Anestimatedfigureof957,000peoplelivewithin10kmbufferzoneoftheSundarbansand 1,157,OOOwithina20kmimpactzonewhodependdirectlyorindirectlyuponitsresourcesfor livelihood(CanonizadoandHossain,1998). ThedemographicprofileofthestudyareasgiveninTable1,2,and3.Allthethreevillagesunderthe studywerewithin5kmoftheSundarbansforest.Familysizevariedbetween3to8whenallthe surveyareaswereconsidered.(Table4).TheaveragefamilysizeinMongla,DacopeandShyamnagar were5.1,4.7and5.0,respectively(DAEOfficerecords),withvariedlevelsofliteracy.Agriculture wastheprincipaloccupationofthepeopleatallthesurveyareas.InMongla,landlesscategorywas dominating;smallfarmcategorywasthemajorgroupinDacopeandShyamnagar.Agriculturewas followedbyfishingandforestrelatedactivities.VeryfewrespondentsinMonglaandShyamnagar wereengagedintradingorbusiness.Someofthesecondaryoccupationswereshrimpcultivation, fishing,shrimpfrycollection,fuelwoodcollection,honeycollection,golpatacollection,workas labourer,andbusiness/trading.InMongla,fuelwoodcollectionwasfoundtobethedominant secondaryoccupation,whereas,inDacopeandShyamnagar,fishingappearedasthedominant Table1:DemographicprofileofMongla,Bagerhat Parameter1MonglaUpazilla*ChilaUnion*1 ChilaVillage** A.Population(No.) Total population Male population Female population Farmingcommunity Populationdensity(No. km-) Literacyrate (%) B.Landholdingcategory t Landless Marginal Small Medium Large Total 177217 96937 80280 13802 636 42.8 2991 3641 3758 2214 1198 131533475 67761895 63771582 2453 31.330.4 522 794 673 310 154 * Source: DAE records,Mongla. ** Source: Canonizadoand Hossain(1998) Table2:DemographicprofileofDacope,Khulna ParameterDacope Upazilla*1Sutarkhali Union* A.Population(No.) Total population Male population Female population Farmingcommunity Populationdensity(No. km-2) Growthrate (%) Literacyrate (%) 175000 91000 64000 25377 501 2.08 37.6 25481 13173 12308 4140 29.634.5 1 Sutarkhali Village** 4689 2362 2327 * Source: DAE records,Dacope. ** Source: CanonizadoandHossain(1998) CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Table3:DemographicprofileofShyamnagar,Satkhira ParameterShyamnagarMunahifonjMunshigonj Upazilla*Union*Village** A.Population(No.) Total population265004309001228 Male population13372115000632 Female population13128315900596 Farmingcommunity465924952 Populationdensity(No. km)135 Literacyrate(%)28.2032.529.2 B.Landholdingcategory(BBS,-) Landless7710650 Marginal11203830 Small121311500 Medium6721750 Large2610290 Total403654200 l Source: DAErecords,Shyamnagar ** Source: Canonizadoand Hossain(1998) secondaryoccupation.Atallthelocations,shrimpcultivationappearedtobethesecondimportant secondaryoccupation.Itmaybenotedthatshrimpisculturedonthesamelandwherericeis cultivated. GeneralLandUsePattern Historicallytheregionwasdominatedbysinglecropi.e.localAmanriceinthepredominantcropping pattern:Fallow-T.Aman-Fallow(BARC,1998).Duringtheearly196Os,theonlycroppingpattern inthesouthernpartsofKhulna,BagerhatandSatkhirawasFallow-Fallow-T.AmanRice(Table5). Croppingpatternsremainedthesameforyearsexceptduringtheearly1980swhenintroductionof modernricecultivation,andmoreimportantly,brackishwatershrimpcultivationchangedthe scenario,andthreedominantcroppingpatternsemergedcontainingshrimpasamajorcomponent inthelandusepattern(Table5).Sincemid198Os,brackishwatershrimpcultivationhasemerged asavitalland-usewiththeemergenceofnewcroppingpatterns,e.g.Fallow-Shrimp-T.Aman (Table5).However,Fig.10showedthepatternsasFallow-T.Aman(LIV)/ShrimpCulturefor Shyamnagar,andFallow%Aman(HYV/LIV)-FallowforDacope. Introductionofmodernricevarietiesinitiatedtheprocessofelimination/extinctionoflocalricevarieties fromthecroppingsystemsintheregion.DepletionoflocalricevarietywastheseverestinShyamnagar amongthelocationsstudied.Table6revealedthatmajorityofthelocalvarietieswereatthestageof near-eliminationorextinction.Particularly19varietieswerereportedasalreadyextinctfromthe region.Theprincipalreasonsbehindsucheliminationwereadoptionofmodernricevarietiesaswellas rapidexpansionofbrackishwatershrimpcultivation. Traditionalvarietyisbeinggraduallyreplacedbymodernricecultivar(s),sincemid-1980s.Withbrackish watershrimpcultivationemergingasanothermajoractivitythelandusepatternappearedasShrimp- Rice-ShrimpcultivationwhereshrimpwasculturedduringJanuarytoJuly-August,followedbyrice cultivation.Insomeconstrainedareas,asinShyamnagar,however,shrimpcultivationwasthesole land-useactivity,witharotationalShrimp-fallowcycle. ---. ___.---~-~~--___~.- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m ___-.- ._-.--... Figure10:Dominantproppingpatternin thestudyregionatpresent ~.~----_-.--.-.n-.mm__I__c---~l-_-~~-^.~_-_-^ II-_x_I~xI-~i-_l^l-._, ~.-l..-x-l--~^_._ --.--_._.^.._-I_ll_lill^ ___^_CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Table4.Socio-economicprofileoftherespondenthouseholdsinthreestudyareas Parameter A.Ageofrespondents(Year) 25-34 35-44 45-54 55-64 65-74 B.Familysize(No.) %Respondent MonglaDacopeShyamnagar 25.0020.0015.00 35.0030.0025.00 15.0025.0010.00 5.0020.00 20.0025.0030.00 3 4 5 6 7 8 C . Education 10.005.0010.00 25.0025.0010.00 30.0025.0025.00 25.002.5.clo30.00 15.0015.002t5.00 5.clo Illiterate Primary Secondary Higher secondary University D. PrincipalOccupation 40.0015.0040.00 35.0055.0010.00 20.0030.0040.00 10.00 5.00 Agriculture Fishing Forest activities Trading/Business E. Secondaryoccupations Finishing Shrimpfry collection Fuel wood collection Golpatacollection Honey collection Labourer Business/Trading F. Landholdingcategory 45.0055.0060.00 25.0025.0015.00 25.0020.0015.00 5.0010.00 30.0040.0045.00 30.0030.0020.00 35.0025.0020.00 20.0025.0015.00 15.0025.0010.00 25.0020.0010.00 20.0010.0025.00 Landless(~0.20 ha)40.0025.0015.00 Marginal(0.21-0.50 ha)25.0030.0020.00 Small (0.51-l.OOha)10.0035.0035.00 Medium (1 .Ol-2.00ha)15.0010.0020.00 Large (>2.00 ha)10.001cr.00 I__~~~~-~~._-_-n_--~--~~~~~--.lII__^~~~~xcIIII~.~~.__._^lll_~,~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m -.--_ Table5.LandutilizationinthecoastalregionadjacenttotheSundarbansduringearly1960sand1990s Region Southernparts of Bhola,Jhalakathi& Pirojpur,Middle partsofPatuakhali, Northernpansof Barguna,Bagerhat, Khulna&Satkhira Landuseduring1963-75 Fallow-Fallow-T.Aman Landuseduring1965-97 Fallow-Fallow-T.Aman Fallow-T.Aus-T.Aman Fallow-Sesame-T.Aman Fallow-B.Aus/Jute-T.Aman Fallow-MixedB. Aus& Aman Fallow-B.Aman Fallow-Fallow-Fallow Grasspea/Fallow-B.Aus/Jute-T.Aman Grasspea/Fallow-MixedB.Aus&Aman Boro-B.Aman Boro- Shrimp(Lobster) Shrimp Fallow-Fallow-Fallow Southernparts of Bhola,Patuakhali, Barguna,Pirojpur, Bagerhat,Khulna andSatkhira Fallow-Fallow-T.AmanFallow-Fallow-T.Aman Fallow-Sesame-T.Aman Fallow-Shrimp-T.Aman Southernparts of Bhola,Patuakhali, Barguna,Bagerhat, Khulnaand Satkhira Source:BARC(1998). Fallow-Fallow-T.Aman Mangrove vegetation Fallow-Fallow-T.Aman Fallow-Shrimp-T.Aman Shrimp-Fallow-Fallow Mangrove vegetation Table6.Statusofricevarietiesinthestudyareas VarietyStatus Modern Location-wisenumber MonglaDacopeShyamnagar 356 328 6714 54 542 627 1315 171324 ManagingRiceCultivation Soilfertilityandpestmanagementaretwomajorelementsinricecultivation.However,weedingin modernvariety(MV)riceisanotherimportantmanagementpractice.Nitrogenandphosphorusarethe twocommonlyusedfettilizers,withagreateremphasisonN(Table7).Introductionofmodernrice varietiesleadtoincreaseduseofchemicalfertilizers,particularlyduringthelast10years.Rangesof commonfettilizersdosesusedinmodernricecultivationhasbeenshowninTable8.Duringfertilizer dealersurvey,itwasrevealedthattheuseofDAP, ZnSO,andGypsumwerealsocommoninDacope andShyamnagar.Thedosageoffertilizersused,particularlyN andP doses,weremuchhigherthanthe dosesrecommendedbyBARC(1997)fortheAEZrepresentingthestudyregion(AEZ-13).Itwasa commonviewpointexpressedbythepeoplethattheexpectedyieldlevelcouldnotbemaintainedif fettilizerdosewasnotincreasedincrementally. _-____^lll.~-l_xI- -~^-_ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Table7.Inventoryoffertilizerusebyrespondenthouseholdsatthreestudyareas Parameter%Respondent MonglaDacopeShyamnagar A.Typesoffertilizeruse Urea55.0075.0065.00 TSP35.0030.0035.00 MP5.0010.005.00 B. Yearofstar-loffertilizeruse l-455.0020.0025.00 5-9 >lO C.Fertilizerdose Increased Decreased D.Cropyield Increased Decreased No change E. Comparativeyieldincreasewithincrementalincreasein fertilizerdose Comparativelyincreased Comparativelydecreased No change A Fertilizer Table6.Fertilizerdosesusedbythericegrowersinthestudyareas Urea TSP MP DAP TSP (USA) ZnS04 Gypsum l- Mongla 150-l87150-200 75-l1575-l20 40-7550-75 Fertilizerdose(kgha-l) Dacope 8-l5 50-75 1 Shyamnagar 175-225 100-l25 50-l00 200-225 100-l25 I O-20 60-75 Introductionofmodernricecultivationleadtotheuseofinsecticidesintheregionduringthelast twodecades(Table9).However,inrecentyears,shrimpcultivationhasalsoleadtowidespreaduse ofinsecticides.Itwasnotedthatexpansioninareaundershrimpcultivationattheexpenseofrice coveragehasresultedinseverityofinsectpestsintherestrictedareasofricefields.Evenlocalrice varieties,whichwereearlierfreefrominsectattacks,havebecomemoresusceptible,inrecentyears. Farmersoftenusedlowerthantherecommendeddosesofinsecticides,butwithhigherfrequencyin application.Thoughtherewasanetover-dosage,efficiencywaslesser,withincreasedinsectresistance againstinsecticides,inrecentyears. --.-^^__x.-- --x_I-__--....._.-._.. ___,..._.-^_.- l^lll.l...._.^.,,.. ._-...-,._._- _.I_..^_-,__^-._, i .,. .l.~-.-._.._.. _____-_-__ -..^__._x..._._,___ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Table9.Inventoryonplantprotectionmeasurestakenbytherespondenthouseholdsatthreestudyareas Parameter A.Methodofinsectpestcontrol Chemicalcontrol Mechanicalcontrol Traditionalcontrol IPM Do not control B.Identificationofinsectpests Canidentify Cannotidentify C.Identificationofinsecticides Mongla 55.00 45.00 45.00 55.00 %Respondent Dacope 75.00 25.00 75.00 25.00 Shyamnagar 80.00 20.00 70.00 30.00 Canidentify55.0070.0070.00 Cannotidentify45.0030.0030.00 D.Useofdosen=11n=15n=16 Uses recommendeddose63.6460.0050.00 Dont use recommendeddose36.3640.0050.00 E.Yearofstartofusen=lln=15n=16 l-563.6420.006.25 6-l018.1873.3356.25 11-159.096.6731.25 15+9.096.25 YieldPotentialsofRice: RiceyieldpotentialinthestudyareascomparedtoregionalestimatesoftheDirectorateofAgriculture Extensionindicatedthattheyieldpotentialofricevarietieswasmuchlessthantheregionalaverage (Fig.11).Atthesametime,riceyieldpotentialhasbeendecreasingacrosstheregion,duetodeclining soilfertility,increasingsoilsalinityandlanddegradation.Yieldreductionsobservedwerebetween29- 35%forMVriceand18-24%forLV rice(Fig.12).Evenseverereductionsupto50%inMVricewere notuncommoninrecentyearsasreportedduringgroupdiscussionswithcommunityparticipants.Ata regionalleveltoo,decliningtrendsinriceyieldwereevident(Fig.13).Reductioninyieldpotentialhas sometimesledtolowerprofitinmodernvarieties,andlossforlocalvarieties(Fig.14);thisinturnhas ledtoa shifttowardsbrackishwatershrimpcultivationwhichhadhighernetreturns(Fig.15)compared toMVricecultivation. VegetableCultivation Vegetablecultivationisanintegralcomponentofthefarmingsystemsofthelocalcommunitiesinthe region,thoughinrecentyearsbothlandareaandproductivityofsummerandwintervegetablecrops havebeendeclining.Ataregionallevel,itwasfoundfromgovernmentstatisticsthatvegetable cultivationhasbeenincreasingintheupstreamaswellasthatundernon-shrimpareas,unlikeinthe studysites,whichwereshrimpcultivationareas.Theprincipalreasonswereincreasedsubmergenceof availablelandandincreasedsoilandwatersalinity.Historicallythecultivationofwintervegetables waslimitedbytheincreaseddryseasonsalinity,thoughinrecenttimes,salinitywashighereven duringsummermonthslimitingsummervegetablecultivation,andevenimportofvegetablesfromother areas,suchasSatkhira,Jessore,Khulnabecamecommonbusiness. ~~_..i__l-__-~-~_--^-___;._~--x-.^------ll^-~-~--~-~~--- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m 4.5 1 ~-~-_- BIDbEEstimate(Upatilla)W/ 4- I 3.5 I 3I h 7 22.5 e 0 .-: 2- 1.5 1 0.5 0. qDAEEstimate(Upadlla)LVi DAEEstimate(Union)MV; kIDbEEstimate(Union)LVI FieldestimateMV qFieldestimateLV Mongla Location DacopeShyarnnagar Fig.11. Yieldpotentialofricevarietiesintehstudyareas 0 -5 -10 -15 -20 -25 MonglaDacopeShyamnagar Location Fig.12.Yieldreductioninricevarietiesovertenyearsperiodinthestudyareas -: ~_.-,..-I__x_I--~~~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m L 3.5 3 2.5 7;2 r =I.5 2 21 0.5 0 19911992199319941995199819971998199920002001 Year(representsprecedingfiscalyear) --~--- Fig.13.TrendsinriceyieldpotentialinShyamnagarduring1991-2001 MonglaDacopeShyamnagar Location Fig.14.Netreturnfromricecultivationinthestudyareas __l_-.~.~-. - ~.-_..x___---__~-I~_~- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS LivestockandPoultry Livestockpopulationintheregionhasbeendecliningrapidly,withreductionsupto90%,withlarger reductionsinShyamnagarandDacope;inMonglalivestockpopulationincreased(Table10).Livestock populationintheupstreamareas,ingeneral,increasedinrecentyears,whichwasoffsetbydrastic reductionsindownstreamareaswhereshrimpcultivationexpanded.Thedeclineinlivestockand poultryrearinginthestudyareaisduetoincreasingscarcityoffodderandgrasses,scarcityof grazinglands,ofdrinkingwater,andwidespreadincidenceofintestinaldiseases,particularlyforcattle andducks.Alltheseproblemsaresuggestedtobeduetoincreasingsoilandwatersalinityasaresult ofshrimpcultivationintheregion.Declininglivestockadverselyaffectingdungproduction(whichalso isusedasfuel),leadingtodecliningorganicmattercontentsinsoils.Withreduceddung,cropresidues andhomesteadplantations,thedependencyontheSundarbansforfuelwoodhasincreasedinrecent years. Table10.Trendsinlivestockpopulationovertimeinthestudyareas Location Mongla Dacope Shyamnagar Livestock I Population(No.)%Change category Cattle Buff al0 Goat Sheep Duck& Poultry Cattle Buffalo Goat Sheep Duck Poultry Cattle74735 Buffalo7533 Goat40213 Sheep20505 Duck33490 Poultry92881 199019952000 1173517550 6351450 11151050 105150 96735130250 44576 1244 13956 3211 50117 206162 l- 2001 49.55 125.35 -5.83 42.86 34.46 34716-22.12 1067-14.23 11915-14.62 3079-4.11 34096-31.97 122354-40.65 45355-39.31 1750-76.77 13200-67.17 6500-68.30 10400-68.95 95975+3.33 1 Source:DLS Officerecords,Mongla,Dacope,andShyamnagar. Fisheries Thetwomajorfisheryactivitiesintheregionarebrackishwatershrimpcultivationandopen-water fishing. BrackishWaterShrimpCultivation: Theattractivepriceofshrimpasanexportitem,muchhighernetreturncomparedtorice,and cheapavailabilityofshrimpfryintheSundarbansestuaryencouragedtherichandinfluential peoplefromoutsidetheregiontostartbrackishwatershrimpcultivation,asacommercialactivity. ShrimpcultivationexpandedinKhulnaregionalmostexponentially.Iteventuallyalsoencouraged, andinmanyinstances,forcedthelocalfarmingcommunitiestoconvertmoreandmorericefields intoshrimpfarms. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m I_--....-_____. ---__--_____- I.- 120000 100000 -80000 Fu r c60000 E 3 z 2 40000 20000 0L qImprovedtraditional EITraditional Mongla ---.--. Dacope Location ____--~...-- Shyam nagar -- Fig.15. Net returnfrom shrimpcultivationin thestudyareas Brackishwatershrimpcultivationwaspracticedtraditionallyinseasonalpondsencircledwithmud- dykesinriceplotsoroutside(Plate1).StartingfromJanuarytoendJuly-September,shrimpfries rearedfor4-7monthswereintroduced. Netreturnfromshrimpcultivationbothundertraditionalpracticeaswellasimprovedtraditional practicewereestimated(Fig.15).Itwasobservedthatshrimpcultivationofferedmuchhigher cashreturnthanfromricecultivation.Highenergyinputshrimpcultivationofferednetreturn rangingfromTk.90000-111000ha-l,whilethatfromundertraditionalpracticesrangedbetween Tk.25000-30000ha-lonlystillmuchhigherthanthatinricecultivation.Thiscontributedtothe shiftfrompaddytoshrimpcultivationintheregion. Thegrowthandproductivityofsweetwaterfishesdecreasedinrecentyearsduetotheincreasein pondwatersalinityasaresultofshrimpcultivation.Althoughshrimpcultivationstartedoffina traditionalmannerwithoutanyfertilizeruse,intensivemethodsareontheincrease,withhigh inputsoffertilizers(Table11)andinsecticides,withatotalof10commoninsecticides(Table12), oftenindiscriminatelyandinhighdoses. Table11.Fet-tilizeruseinshrimpcultivationthestudyareas Fertilizer Urea TSP MP Gypsum Lime Cow dung Mongla 35-70 30-40 260-300 120-350 200-400 Fertilizerdose(kgha-l) Dacope 35-70 30-40 260-300 150-400 150-350 Shyamnagar 40-115 40-75 260-300 180-750 150-350 ~_~_x_-I__--. _-__^_ _.,..-__x__._..-_^.- .._._~~~..---I_-,__lx---.-~.__^.--_-~ _~~~--____I~~-.l.-~--~..-~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Table12.Insecticides/chemicalsusedbytheshrimpcultivatorsinthestudyareas Insecticide A. Granularformulation Rotanol Pilarcron CV PlantFood B. Liquidformulation Dimecron Ripcord Hildon Thiodin F-organ Y-organ Bleachingpowder Potassium(G) Benicron Renafitez Renamycin Azodrin Clinicalsolution Homaeopathicpreparation Group Rotanon Organocarbamate Unknown Organophosphate Cypermethrin Organophosphate Organophosphate Unknown Unknown Potassium Organophosphate Unknown Unknown Organophosphate Unknown Unknown r Mongla * lArea Dacope * * Shyamnagar Shr -imphasemergedasanimportantexportitemanda sourceofhardforeigncurrencyforBangladesh duringthelasttwodecades.In1985-86,Bangladeshexported13631tonsoffrozenshrimp, whereasin1998-99,theamountwas20086tonswithatotalvalueofTaka1162.2crore(Fig.16). Highervalueofshrimpintheworldmarketencouragedthequantumexpansionofbrackishwater shrimpcultivationinthecountry,particularlyinthecoastalregion.Shrimpcultivationwasstarted intheregionofSatlkhiraduring197Os,followingtraditionalprocedures.Eventuallyitbecamea majorenterpriseinthewholecoastalregionofBangladesh,particularlyintheKhulna,Bagerhatand SatkhiraDistrictsinthesouth-west(75O/Oofthetotalproduction),andtherestinthesouth- easternregionofthecountry(Mazid,1998).Startingfrom51812haundershrimpcultivationin 1983-84,theareaundershrimpcultivationroseto141353habytheendof1998-99,withgreatest expansionintheKhulnaDivisionwheretheconditionsweremorefavourableandthecostofproduction waslower(Fig.17).SatelliteimagesproducedbySPARRSO(2001a)(Figs.18and19)alsoconfirm suchexpansion. Open-waterFishing: Openwaterfishinghasbeenthetraditionaloccupationofthousandsoffishermenintheregion. However,inrecentyearsthenumberofseasonalfishermenhasgoneup.Chanterasri(1994)estimated thattherewere110,000fishermenengagedinshrimpfrycollectionin1993,increasingbymorethan 15%eachyear,withanestimatednumberof200,000(CanonizadoandHossain,1998),whichperhaps wouldnowbemorethan300,000.Table13showedtheamountoffishcollectedpertripbythe respondenthouseholds.ForestDepartmentrecordsoffishcollectionwereprovidedinTable14. Gearstraditionallyusedleadtodestructionofnumerousotherspeciestoo.Anotherlethalpractice inrecentyearshasbeentheuseofpoison/insecticide,fishermenusingThiodinalndHildonsmuggled fromIndiaforthispurpose.Useofthesechemicalscausedtotaldestructionofallfishesandother aquaticlivingbeingswithinagivenarea. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m --_-i -.--.~---.----ll.--.----._ -..-.-.__-._-. -._-_,_._.___I_ Table13.ResourcescollectedfromSundarbansbytherespondentfarmhouseholds ~Resource A.Timber Season Collectionper season(t) Mongla June-August 11.00-12.00 Collectionbyhousehold Dacope Oct.-Feb. 18.00-20.00 Shyamnagar Oct.-Feb. 11.00-12.00 B.Fuelwood Season Collectionper season(t) C.Golpata Season Collectionper season(t) I--I year-round 11.00-12.00 I Oct.-Feb. I year-round 18.00-l9.0011.00-l9.00 Oct.-Feb.Oct.-Feb.Oct.-Feb 15.00-l6.0022.00-23.0018.00-l9.00 D.Honey Season Collectionper season(kg) E. Fishing Season Collectionper trip(Tk.) Feb.-Apr.March-AprilMarch-April 0.15-0.200.08-0.100.5-0.7 Year roundYear roundYear round 200.00-250.00150.00-200.00200.00-250.00 F.Shrimpfry Season Collectionper day(Tk.) Year roundYear roundYear round 150.00-l70.00130.00-l70.00150.00-200.00 Table14.CollectionoffishresourcesfromtheSundarbansunderlegalpermits YearAmount Fish(000t)Bagdashrimpfry(Million)LargeShrimp 1986-874.620.82 1987-884.5114.1391 1988-893.8630.43367 1989-903.6770.34270 1990-914.9572.69241 1991-924.83110.36317 1992-935.59127.97307 1993-945.14231.15274 1994-955.39263.41281 1995-965.99253.07277 1996-974.29142.22 1997-984.28127.98 1998-993.5181.41 1999-20003.45101.36 2000-013.1496.08 Source:CanonizadoandHossain(1998);FAOIUNDP(1998),Karim(1995);FD records SmallShrimp 191 104 132 126 533 791 855 593 655 CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m 00000 80000 60000 40000 20000 0 1 ,0Reduction(t) 14Oc 12Oc 1ooc 800 600 400 200 0 Fig.16. Nationalshrimpproductionandexportstatisticssince1985-86 160000 140000 120000 100000 2 -80000 $60000 ClChittagong ABarisal+Dhaka 0Total 0Khulna Year Fig.17. Divisionwiseexpansionof shrimpcultivationarea since1983-84 ShrimpFryCollection Themainimpetusbehindbrackishwatershrimpcultivationinthemangroveregionwasthe abundanceofshrimpfriesintherivers,canalsandestuaries.Shrimpfrycollectionsupported resource-poorpeoplegroups,particularlywomenandchildren.Atotalof44766shrimpfrycollectors wereidentifiedinthethreestudyareas.ForestDepartmentstatisticsfrom1986-87to2000-01also showedthatshrimpfrycollectionhasbeenincreasingconsiderablyintheSundarbansregion(Table 14).Itmaybenotedthatthesefiguresarebasedoncollectionsunderlegalpermits.Butthe unofficialcollectionfiguresaresuggestedtobemanymoretimes. Themajoradverseimpactofshrimpfrycollectionwithfinemeshnetswasthelarge-scaledestruction ofotherfishspecies(Plate2).Recentlygovernmentputabanonshrimpfrycollection.Without _~_x.~--,-_I__---x^___l. . - . ._ll.- - - - , ~) _I - - _- - ^_- I __I _. . , . _- . . . ~_^ xI I - I - . -. =. _x- , . - - _____-__l_--~_l^_-~--~~~ .^l-----llllCASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m .--- --.-- .- ---- -.-.. Figure18 :SatelliteimageoftheSundar~ansanditssurrounding areasduring1984-85(LandsatMSS) ~~~_-.-~~-~l,___~-~l .^__-~~--~ -1.__1~-~~~.~~.-..~~__~_CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Figure19:SatelliteimaeoftheSundarbansanditssurrounding areasduring7 988(LandsatTM) -~_____-.--___^-~__^.- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m alternatelivelihoodsources,suchasuddenbancouldcreateadverseimpactonthepoorersections ofthesociety.However,theForestDepartmenthasyettoenforcesuchaban. PondFisheries Mostofthehouseholdsinthestudyregionhadpondsintheirhomesteads.Localpeopleusedtorear commoncarpsandothersweetwaterfishesintheseponds,However,rearingofestuarinespecieswas alsocommon.ThetotalnumberofpondsinMonglawas2622covering600.45ha.Therespective figuresforDacopewere2016comprisingof25.87ha.InShyamnagar,thenumberofpondswas2085, whichcoveredaround135.06haofland.Majorityoftherespondenthouseholdsinthestudyregion hadpondsintheirhomesteads,withpisciculturefollowingtraditionalprocedure,withoutanyenergy inputs;however,supplementalfeedsarealsonowusedfrequently.Pondfisherieswerebasedon cultivationofcommoncarps,othersweetwaterfishes,andestuarinespecies.Butthistraditional practiceisnowunderseriousthreatduetoincreasedsalinityofpondwater,arisingfromextensive shrimpcultivation,whichisdetrimentalforcarpsandothersweetwaterfishspecies. HomesteadPlantation Aninventorymadeofthehomesteadsoftherespondenthouseholdsshowedatotalof14,16and18 fruitspecies,alongwith8,10and12forestspeciesidentifiedinMongla,DacopeandShyamnagar, respectively.AveragefruittreestandsperhomesteadwasthehighestinDacope,andtheleast numberswereinthehomesteadsinMongla.Inthecaseofforestspecies,thehighestnumberof standswasfoundinthehomesteadsofMongla,whereastheleastwasobservedinDacope(Table15). Itwasreportedthatbothnumberandproductivityofhomesteadplantations,particularlysweetwater fruitspeciesweredeclininginrecentyears.Theprincipalreasonidentifiedwastheincreaseinsoiland watersalinityduetoshrimpcultivation. Thecommonvisiblesymptomsidentifiedweregrowthretardationincludingyellowingofleaves,absence offruiting,prematurefruitdrop,ultimatedeathofthetreeitself.Incaseofoldandmaturetrees,the symptomstartswiththedeathoftheapicalportion(Plate3).Deathofsaplingstartonlywhenthe rootsystemreachesthedeepersoilprofile,whenitis3-5yearsold.Declineinnumberandproductivity ofhomesteadplantationshasledtoshortageoffodder,fuelwoodandtimber,aroundhouseholds,apart fromdecliningediblecomponent. TimberandNon-timberForestProducts(NTFPs)fromtheSundarbansForest Sundarbanshasbeenplayingavitalroleinthelivelihoodoftheruralpeopleoftheregionfor generations.Theforestprovidestimber,fuelwood,leavesforroofthatching(Nypafruticans),fish, shrimpfry,honey,wax,grasses,fruitsandotherminorresources.Italsooffersecologicalbenefits, suchasprotectionfromstormsandtidalsurges.WhatisgiveninTable13isindicativeoftheextent ofdependenceofthepeopleonNTFPs,sincethesamplingsizewassmallinthisstudy.Detailsof resourcecollectionfromtheReserveForestspreadoveratimeperiodisshowninTables16and17. ThefiguresprovidedbytheForestDepartmentrepresentonlythecollectionunderlegalpermits. However,actualamountscollectedlegally,aswellasthatillegallyobtainedaremuchmore.Confiscation ofNTFPsdonebytheForestDepartmentalsorevealedincreaseillegalloggingoperationsinrecent years(CanonizadoandHossain,1998;FAO/UNDP,1998).ThedependencyontheSundarbans,largely forfuelwoodhasincreasedconsiderablyinrecentyears,whichwasaround75-100%comparedtoonly lo-25%,twodecadesago. Table17showsthetrendsincollectionofselectedplantresourcesfromtheSundarbanssince 1984-85.Timbercollectionremainedsteadyduringthedecade1984-85and1994-95,butdeclined progressivelyafterwards.However,collectionofotherresourcesincreasedduringthesameperiod, particularlythatoffuelwood.Illegalloggingofeconomicallyimportanttimberresourcessuchas __I___^__.,.__^ . - . ._l_.._~.,_^____I_. _. . .__ , ___l__._l_.__-_l. . l _._.-.I_. _. -___, n_^_..,__. _- -__, - . l-..r,_-___,__I^__ - - . . . . . _- _. . . . , _. ^._.._..,_.r_^-._--__-~, CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Table15.Plantationresourcesinthehomesteadsofrespondenthouseholdsinthestudyareas Treespecies A.Fruitspecies Mongla Averagenumber/homestead DacopeShyamnagar Coconut Date palm Jujubi Sapota Mango Guava Blackberry Palmyra palm Papaya Betel nut Jackfruit Banana Pome granate Jamrul Lime Custardapple Wood apple Tamarind Golden apple Kodbeli Averagestands(No.) B. Timberspecies 11.648.127.88 4.113.4511.55 0.641.751.33 0.641.501.77 4.053.254.50 3.111.672.94 0.580.120.50 0.940.804.11 0.171.670.77 5.648.230.94 0.701.080.27 1.171.750.83 0.050.780.11 0.17 0.200.50 0.05 0.05 0.05 0.750.16 0.27 33.6139.1738.25 Sissoo0.111.500.22 Mahogoni2.411.670.88 Babla0.233.330.27 Shirish4.31 Chambal7.64 Eucalyptus0.050.05 Koroi0.111.100.33 Arjun0.051.36 Shrishti6.66 Ziga1.400.55 Shishtamool0.66 Gewa0.500.27 Shimul0.25 Krishnachura0.05 Neem0.451.27 Mehedi0.500.05 Khoia babla1.00 Averagestands(No.)14.9112.0612.26 ____^~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m ~-_..-.- ---- II-----_-...--___-_.-__~ Table16.CollectionofselectedfloralresourcesfromtheSundarbansunderlegalpermits r YearrAnnualcollection 1 1984-85 1985-86 1986-87 1987-88 1988-89 1989-90 1990-91 1991-92 1992-93 1993-94 1994-95 1995-96 1996-97 1997-98 1998-99 1999-2000 2000-01 -r Amount Timber (millioncft) 2.8 3.15 1.21 2.49 2.42 0.6810.11 1.646.93 3.016.12 1.887.24 2.295.72 0.481.41 0.170.95 0.191.33 0.131.68 0.183.44 0.268.2 Fuelwood (millioncft) 0.06 0.06 0.07 0.08 0.07 GolpataGmSSeS (milliont)(000t) 0.069.31 0.0611.06 0.0711.74 0.0813.44 0.0713.53 0.0711.57 0.077.29 0.074.74 0.075.9 0.076.62 0.066.77 1.694.02 1.575.87 1.45.26 12.12 2.76.78 0.923.95 Source:CanonizadoandHossain(1998);FAO/UNDP(1998),Karim(1995);FDrecords. Hantal(t) 8910 5412 6087 7848 8339 7203 6747 9032 6053 6725 1712 712 Table17.CollectionofselectedminorresourcesfromtheSundarbansunderlegalpermits Honey(t)Wax(t)Mudcrab(t)Shell(000t) 1984-8525764.242.69 1985-86 1986-87 1987-88 1988-89 1989-90 1990-91 1991-92 1992-93 1993-94 1994-95 1995-96 1996-97 1997-98 1998-99 1999-2000 22656.4 23057.4915 22355.7615 10025.1314 14736.5626 21052.7686 16043.46274 18345.86491 10726.63527 9122711 16139851 193895 13133824 14937440 20852488 130 2.67 3.2 3.62 3.66 3.17 3.35 4.36 3.95 4.28 1.02 0.82 3.3 2000-01 SourceCanonizadoandHossain(l998);FAO/UNDP(1998),Kariml(1995);FD records. 15 15 14 26 86 274 491 527 711 851 895 824 440 488 . - I - ^_^__-__l_cll__l~-~-~-~~.~-~~~~~ ~__I~~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m ...-t..l.-.,... Sundritimber(cu.m .) j El Sundrifirewood(ton) Fig. 20. Confiscationof illegallycollectedtimberand fuelwoodfrom SundarbansReservedForest Sun&-iisrampant,asseenfromtheconfiscationdonebytheForestDepartment(Fig.20)(Canonizado andHossain,1998;FAO/UNDP,1998). Table14showsthemajorfishresourcecollectedfromtheSundarbanssince1986-87,andthere wasdecliningtrendduringrecentyears,particularlytheharvestofcommonfishes,largeshrimpas wellasshrimpfrycollection.Thiscouldbeexplainedasduetoover-harvestingoveraperiodof time,andhabitatdegradation.Interestingly,declineinavailabilityofthemajorfishresources increasedthepressureonminorfishese.g.smallshrimpwhichwasbeingincreasinglycollectedin recentyears. Collectionofotherminorresourcessuchashoney,bee-wax,mudcrabandshellsalsoshoweda decreasingtrendinrecentyears(Table17).Mudcrab,whichisapromisingexportitemafter shrimp,showedanincreasingcollectionupto1996-97,withasubsequentdecline.GreenKeora fruitcollectionincreasedinrecentyears.LandlesswomenoftencollectedKeorafruitsforsaleinthe localmarkets.Thesefruitsareusedasanadditiveinlentilsoupsandotherfooditems.Manyplants usedintraditionalmedicinesarealsocollected.TurtlecollectionbyHinducommunitieswasalso reported.However,turtlepopulationreduceddrasticallyinthestudyareas. Themajorfactorsfornaturalresourcedepletionwereidentifiedaspopulationpressure,poverty, extensiveshrimpcultivation,over-fishing,fishingwithinsecticideapplication,illegallogging/hunting, poorgovernance.Theremedialmeasuresidentifiedwererestrictedshrimpcultivation,banon fishinginsidetheforestareas,controloverindiscriminateuseofinsecticidesinriceandshrimp farms.Itwasreportedthatvillagersandloggersoftencollecteventreesaplingsforfuelwood, irrespectiveoftheirothereconomicvalues.Suggestionsalsoemergedforimprovingforest managementpractices,stopillegallogging/hunting,checkingorganizedcrimewithintheforested ~~ ~.~____1^^_~_1__--~CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m areas,deploymentofriverpoliceandhonestforestpersonnelonly.Animportantsuggestionwas madeforalternateincomesourcesfortheresource-poorgroups,toreducethepressureonthe SundarbansReserveForest.Apartfromeffectivemanagementdecisions,provisionofalternate incomesourcesfortheresource-poorwasalsosuggested.Theparticipantsidentifiedproblems suchastigerandcrocodilemenaceaffectingthelocalpopulation,andunduepressuresputonlocal people,asproblemsofmanagingtheforest,fromtheirperspective. EcologicalIssues Twomajorissuesemergefromthepreviousdiscussionsasresponsibleforecosystem/landscape damage:(a)modernricecultivationand(b)brackishwatershrimpcultivation,thelatterbeing moreseriousthantheformer: GISmappreparedbySPARRSO(2001b)basedonthetimeintegralimagestakenbyNOAA satellite(Resolution1.1X1.1km)duringOctober2000revealedadverseimpactuponAman riceandotherricevarietiesgrown,andreducingtheircoveragetolessthan40%intheregion includingmajorpartsofthestudyareas(Fig.21),oftenduetolandconversiontoshrimp culture. Shrimpculturecausedseasonaltransformationofuplandagro-ecosystemsintothosesimilarto lowlandecosystems.Suchtransformationresultedinthereductioninlandareaavailableforrice, vegetablecrops,grazinglands,homesteadareas,andnaturalecosystems;yieldreductioninrice wasanotherconsequencearisingfromincreasedsalinity(Plate4). Increasedinsectpestproblemsoccurredintwoways,firstly,duetoexpansionofmodernrice varieties,whichattractmoreofinsectpests;secondly,withtheexpansionofshrimpcultivation, ricecoverageareadecreasedsubstantially.Asaresult,insectpestsattackedmoreseverely,the nowreducedricecropcover.Insectpestproblemspromotedinsecticideuse. Submergencewithbrackishwateralsoincreasedsoilandwatersalinityaswellasputadverse impactsonthephysico-chemicalpropertiesofthesoilsconsiderably. SatelliteimagesclearlyrevealedthatforestclearinghasstartedintheSundarbanssince1975 (Fig.22)andlatertheseareashavebeentransferredintoshrimpfarms(Fig.23).Forestclearing forestablishingshrimpfarmshasalreadydestroyedtheChokoriaSundarbansinthesouth-eastern coastalbeltofthecountry.During1980stheentireChokoriamangroveareawasbroughtunder shrimpcultivationthroughtheinitiativesofthepolicymakersincollaborationwithinternational donors.AtpresentthedenudedmangroveforestwasstandingwithfewscatteredSun&itrees. SuchencruachmentofforestlandforestablishingshrimpfarmshasbeenaproblemalongtheAsian coastalzones,e.g.thePhilippines(Ajiki,1985;Primavera,2000). Further,over-crowdinganddisturbanceoftheriverbanksbyshrimpfrycollectorsaswellasby fishermenhavealsocausedriverbankerosionwithintheforestedareas(Plate5). Unplannedshrimpcultureandricecultivationthroughmodernmethodsinthestudyareas,as inothercoastalareasofKhulna,BagerhatandSatkhiradistrictshadseriousimpactsonecosystem functioning,alteringcoastalecology(Mazid,1998) Intensiveuseofchemicalfertilizersinricecultivation,andlandsalinizationwereidentifiedas twoimportantcausesfordeterioratingsoilfertilityandlossoflandproductivity.Declining trendsinriceandvegetablesyieldpotentialsmarkedtheseverityoftheproblem.Inrecent yearsfarmerswereincreasinglyusingfertilizerse.g.limeandgypsuminshrimpfarms. Deteriorationofsoilhealth,reducedbiodiversity,andincidenceofhumandiseaseswereidentified assomenotableoutcomes. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m 25, A.Passurriver,MonglaPort(SRDI,2001;RahmanandAhsan,2001) JanFebMar AprMay JunJul AwSep OttNovDee Month B.Shibshariver,Paikgacha,Khulna(SRDI,2001;RahGnandAhsan,2001) L 25 01995 ::19961997 x1998 x1999 02000 JanFebMar AprMay JunJul AwSep OttNovDee Month 36 C.Kakshialiriver,Kaligonj,Satkhira(Source:SRDI,2001) I01998 % j 01999 2%/A2000 I JanFebMar AprMay JunJul AwSw OttNovDee Month D.Munshigonjriver,Munshigonj,Shyamnagar(Source:DoF,Shyamnagar,Satkhira) --- 01996 1997 0A1998 0m20001999 JanFebMar AprMay JunJul Month AugSep OttNovDee Fig.21.RiverwatersalinityatdifferentlocationsinBagerhat,KhulnaandSatkbira -l___l~~.-~-.-____-.~.-._.._.....,.x._.,^,.__-..-.-~-.^..-.,-__._^____l__.x;_^_---_,-_;__~_-_-~-I__.--~~~~---x.--L- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Figure22 : SatelliteimageoftheSundarbansforestnearShyamnagar showingforestencroachmentduring1975(tandsatMSS) R$574f CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m w Figure23 : SatelliteimageoftheSundarbansforestnearShyamnagar showingshrimpareaexpansionwithintheforestduring 1998(LandsatTM) 22fZWW rf4 695*l~,EBOfbwF84-645-Fit6?3lrE Source:SPARRSOReportonStudyonOwwdationofMangrovsForestDuetoShrimpFarming UsingRemoteSensingandGISin theBangladeshCoastalRqion,2001 221Cxr-N ~- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMSm lSoilsalinityis themostdominantfactordeterminingcropproductionintheGangestidalfloodplain, wheredryseasoncroppingishandicappedbyincreasedlevelsofsoilandwatersalinity.Conversely, salinitywasalsothesingleimportantfactorcontributingforbrackishwatershrimpcultivation. lIncreasedsalinitylevelsduringnormalpeakperiods(March-May),andbeyondthepeakperiods werereported(SRDI,2001;RahmanandAhsan,2001;DoF, 2001)insoil,riverwater,groundwater andpondwater. lIncreasedpondandgroundwatersalinityhasalsocausedproblemsforirrigationanddrinking watersupply(Plate6). lSalinitycausedseverefoddercrisisaswellasintestinalproblemsandotherdiseasesinboth humanandlivestock(Plate7). lIncreasedsalinitywasalsoreportedtoberesponsiblefortop-dyingofSundri(Heretieraspp.) andotherforesttreespecies(Plate8)(Bhuiyan,1994;Grepin,1995). lFertilizerandinsecticideuseinmodernagriculturalpracticeshavecausedpollutionofsoiland waterresourcesleadingtoadverseimpactsonsoil/aquaticfloraandfauna.Fishingwithpoisons andinsecticideswithinforestedareaisanothermajorproblemwithadverseimpactsonecology andbiodiversityoftheSundarbans.Groundwatercontaminationduetouseofagro-chemicals- accumulationofN andP, andtoxicresiduesofcertainpesticidesarereported(FAO/UNDP,1998), leadingtoeutrophicationofrivers/toxiceffectsonthefoodchain.Atleastfiveinsecticideswere identifiedwhichwerealreadybannedfortheirhightoxiceffectonhealthandenvironment. lWithintroductionofmodernmethodsofricecultivationandbrackishwatershrimpcultivation, itisanticipatedthatwithinnext5-10yearsnolocalricevarietywillbeusedintheregion.Apart fromthelossofvaluablericegermplasm,crisisinavailabilityofthatchingmaterials,fodder,and biomassfuelareanticipated.Shrimpcultivationhasalsoreducedareasundervegetables, sesame,jute,linseed,andotherminornon-cerealcrops. lIncreasedsalinityhasresultedingrowthretardation,non-bearing,prematurefruitcrop,and evendeathofthetreespeciesdependentuponsweetwateravailability.Adverseimpactson homesteadplantationhasincreasedthedependenceofthepeopleforfood,timber,fodderand biomassfuelontheReserveForest. lDeclineinsweetwaterhasbeensuggestedtohavecontributedtodecliningplant,animal diversityincludingbirds. OtherSectorsAffectingtheEcologyoftheSundarbans: AnumberofotherfactorsdeterminedamagetotheSundarbansecosystem: lEngineeringstructureswereconstructedinthecoastalregioninthe1960stoprotectagricultural cropsfromintrusionofsalinewater.Theimpactofthiswassiltationofthemajorriversinthe Sundarbansregion(FAO/UNDP,1998).Thesestructuresalsoencouragedunplannedgrowthof shrimpcultivation,connectivitybetweenvillageagro-ecosystemswhichinturncausedecological degradationanddecliningcoastalfishresources(Islametal.,1998). lTherestrictionontheflowofGangesriverthroughtheFarakkaBarragebuiltduringthe1960s haditsmajorimpactontheSunderbans(Islameta/.,1998).Itcausedreductionofsweetwater flowthroughtherivers.Thetop-dyingofSundritreeisperceivedtobeduetothereductionof sweetwaterflow. lIndustrialsetupsintheupstreamareasoftheSundarbanswerealsoresponsiblefortheecosystems damage.Thewastewaterdischargesbytheseindustriesandfactorieswerealsoresponsiblefor waterpollutionwhichwerebeingcarriedtotheSundarbansthroughthePassur-Shibshariver systems(ESCAP,1987;Wahid,1995). -*_..-.^x__..___^______.-_,.__x,~_-...- .l~-~.~.i~~~~~-~-n-^--l---.I. . _-__..._..,....--.x.x..--_---_.-_-~_--,-.-__;_-_-.- -~~.-_.^x.-I--.I....--_-._^___I____ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m lOilpollutionisanotherfactoradverselyaffectingtheenvironmentofSundarbans(Wahid,1995; Grepin,1995).Oilslicksderivedfrommechanizedboats,fishingtrawlers,passengerboatsand shipscausedamagetotheplantsaplingsandfauna1species(Lewis,1983).SeedlingsofHeritiera andExcoecariaarefoundtobeverysensitivetooilpollution. Socio-economicIssues Brackishwatershrimpcultivationbroughtmajorchangesinthesocio-economicsettingsofthe ruralcommunitieswhichincludedincreasedsocialconflictsandsocialdisharmony,andfragilityto foodsecuritysystemintheregion. Shrimpfarmsforcedthericegrowerswithinoralongsidetheseshrimpfarmstoconverttheir paddylandintoshrimpfarms,havingnoscopeforricegrowinginthearea. Inthecaseofjointventurefarms,socialconflictswere:deprivationofindividuallanduse choices,problemsofjoint-ownershipoflands,righttosharebenefitsequitably,courtcases, harassmentofpoorersectionsofthesociety,etc.bytherichandinfluentialpartners(Nuruzzaman, 1998). Incaseofleasingarrangements,themajorsocialimpactisdenialoftherightbenefitdefinedin theleaseagreement,deprivationofterminalbenefits,unduedelaysinshrimpharvestwhich hamperedricetransplantingschedule,etc. Decreaseincoverageareasofriceandothercropsincludingvegetablesduetotheexpansionof shrimpcoverageresultedinlesserproductionofthesecommoditiesintheregion,leadingtheir areastofooddeficitareas.Declininglivestockandpoultryleadtoshortagesinmeat,milk,egg, etc.Thisapartfromreducedincomeofcertainresource-poorgroups,particularlysmall,marginal andlandlessgroups. Considerableamountsofrice,vegetables,livestockproductsandotheragriculturalcommodities werebeingimportedfromotherareastomeetfooddemand.Thisresultedinthehigherpriceof essentialcommoditiescomparedtootherareasoftheregion.Theresource-poorcommunitieswere theworstsufferers.Changeinfoodhabitsofresourcepoorgroupswerealsoobserved,asa consequence. Intensiveshrimpcultivationbyoutsidersleadtosurpluslabourandunemploymentproblem, thesefarmsbeingnowownedbyrichoutsiders.Thesefarmoperatorsoftenimportedcheap labourfromoutsidetheregion,aggravatingsocialtension. Theendresultsofincreasedsocialconflictsandsocialdisharmonyintheenvironmentwere:fragile foodsecurity,evictionfromland,surpluslabour,unemployment,increaseincostoflivelihood, leadingtoaviciouspovertycycle.Theultimateoutcomewastheincreaseddependencyonthe naturalresourcesoftheSundarbansecosystem,andmoredegradationarisingtherefrom,as revealedthroughthestudy.Shrimpcultivationdidnotbringanybenefitstothelivelihoodofthe ruralcommunities,ratherjeopardizedthesocio-economicsettingsofthewholecommunities,and atthesametimeitturnedouttobethemajorfactorresponsibleforincreaseddegradationofthe Sundarbans. Itwasdifficulttorecommendprotectionmeasuresfromthefindingsofashortdurationstudy.Still someguidelineswereputforwardforconsiderationtocombatthewholerangeofissuesencountered duringthisstudy. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m PolicyIssues lFormulationoflawsandregulationstorestrictShrimpcultivationandtoreduceencroachments toagriculturalaswellasforestlands. lExpandtheareasunderprotectedwaterbodiesandmangroveecosystems. lPromoteinterdisciplinaryeffortsinvolvinggovernmentalandnon-governmentalagenciesto conservenaturalresourcesandcreateawarenessontheadverseimpactsofpresentunsustainable systemsofShrimpcultivation,fishing,shrimpfrycollection,andNTFPharvests. lEmpoweringtheDepartmentofFisheriestomonitor,manageaswellascontrolthefishery resourcesinsidetheSundarbans. lCreatingalternateemploymentand/orincomesourcesfortheresourcepoorgroupsinorderto reducedependencyontheforest. lLawstoprotectsmallfarmersinterestsincaseoflandleasingarrangements,aswellasjoint venturefarmsforshrimpcultivation. ManagementIssues EnforcementoflicensingsystemforestablishingofShrimpfarms. BringingtheShrimpfarmsunderimprovedmanagementsystems,regardingthelayoutofthe farmsandmanagementpractices. Initiativestopopularizerice-fishculturebyusingGoldaShrimp(SweetWaterShrimp). Restrictiononshrimpfrycollectionandfishingbeyondseasonandfromprotectedareas. Restrictiononusingoffinemeshnetsandinsecticidesforshrimpfrycollectionandfishing. Establishmentofsufficientshrimphatcheriestoencouragefryproductionlocally. Arrangeregulartrainingontheimprovedcatchingmethodsofshrimpfryandfishes, Salinitytolerantcropandvegetablevarietiesshouldbedevelopedandintroduced. Strictcontrolontheuseoffertilizersandinsecticidesinricefieldsandshrimpfarms. MassivecampaignregardingthelethalimpactsofusinginsecticidesforfishinginsidetheSRF. Developmentofintegratedpestmanagement(IPM)packages. Socialforestryandriversideforestryprogrammestobedevelopedfortheregion. Replantingandregenerationprogrammesinthedegradedforestareas. Enforcementoflawsandregulationsregardingillegalloggingandhunting. Conclusions Throughthisstudymanykeyissueshavebeenidentifiedwhicharelinkedwithasteadydeclineinthe TraditionalEcologicalKnowledge(TEK)baseofthelocalcommunities.Thisinturnhasbeenresponsible fordecliningqualityoflifeforthelocalpeople.Itwasfeltnecessarytomonitorvariousenvironmental parametersovertimeandspace,togetabetterunderstandingoftheissuesinvolved.Theultimate messagearisingfromthisstudyisthatshrimpcultivationintheSunderbansberestrictedto sustainablelevels,ifnotabandonedaltogether.Formeetingwiththelivelihoodneedsofthelocal people,andtoprovidethemwithabetterqualityoflife,itisimportanttobuildupontheirlocal knowledgebasewithappropriateinputfromformalknowledgebaseandtechnologies.Conservation ofthiscriticalecosystemshouldbebasedonabetterunderstandingofthefunctioningofthis uniquesocio-ecologicalsystem. .._. ;^_~-__x_____...^-_-.I...I. -I_^-- ---._r_^^___.~_^_...----..---^-n_.^,(I. I- .---- ^^. ..I.-. .,... _ . --__-__,...,.--.l_m_l,. ..__..^.._.^ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m . References Ajiki,K.1985.ThedecreasesofmangroveforestsanditseffectonlocalpeopleslivesinthePhilippines, pp.51-54.In:Kikuchi,T.(ed.),RapidSeaLevelRiseandMangroveHabitat.InstituteforBasin EcosystemStudies,GifaUniversity,Gifa. BARC.1998.ChangesinCroppingPatternsinBangladeshoverlasttwodecades.Pp.10. BARC.1997.FertilizerRecommendationGuide.BangladeshAgriculturalResearchCouncil,Dhaka, Bangladesh. Bhuiyan,M.R.1994.DraftFinalReportoftheSoilScientist,FAO/UNDPProjectBGD/84/056, IntegratedResourceDevelopmentoftheSundarbansReservedForest.Khulna,Bangladesh. Canonizado,J.A.andHossain,M.A.1998.IntegratedForestManagementPlanfortheSundarbans ReserveForest.GOB/WBForestResourcesManagementProjectTechnicalAssistanceComponent. Chantarasri,S.1994.DraftReportonFisheriesResourcesManagementfortheSundarbansReserved Forest,FAOP/UNDPProjectBGD/84/056,IntegratedResourceDevelopmentof theSundarbansReserved Forest,Khulna,Bangladesh. DoF.2001.OfficeRecordsonmonthlyriverwatersalinitymonitoring.DepartmentofFisheries, Shyamnagar,Satkhira. ESCAP 1987.CoastalEnvironmentandManagementPlan forBangladesh;UnitedNationsSocialCommission forAsiaandthePacific,Bangmkok,Thailand.PublicationNo.81/ESCAP/618. FAO/UNDP.1998.IntegratedResourceDevelopmentoftheSundarbansReservedForest,Bangladesh. Vol.1,1998.FAO/UNDP,Dhaka. Grepin,G.1995.1995.DraftFinalReportonMangroveEcology.FAO/UNDPProjectBGD/84/056,Integrated ResourceDevelopmentoftheSundarbansReservedForest.Khulna,Bangladesh. Hossain,2.andAcharya,G.1994.MangrovesoftheSundarbans.Vol.2:Bangladesh.TheIUCN, WetlandsProgramme,IUCN,Thailand. Islam,M.A.,Awal,S.,Rahman,M.S.,andMiah,M.A.H.1998.Theeffectsofhumaninterventionson thefisheriesresourcesofGangesFloodplainsandtheSundarbansEstuary.Proc.NationalSeminaron IntegratedManagementofGangesFloodplainsandSundarbansEcosystem,16-18July,1994,Khulna, Bangladesh.Pp.112-122. Islam,M.S.andSaha,U.K.1998.IntegraednutrientmanagementofGangeticFloodplainSoilsof Bangladesh.Proc. IUCN.1994.TowardsSustainableDevelopment:TheNationalConservationStrategyofBangladesh, MinistryofEnvironmentandForest,GovernmentofBangladesh. Lewis,R.R.1983.Impactofoilspillsonmangroveforest,biologyandecologyofmangroves.Tasksfor VegetationScience.H.J.Teas(ed),Vol.8. Mazid,M.A.1998.StatusandPotentialofShrimpFarminginKhulnaRegion.Proc.NationalSeminar onIntegratedManagementofGangesFloodplainsandSundarbansEcosystem,16-18July,1994, Khulna,Bangladesh.Pp.133-140. I . . _- . . . - _--_. -__^ I . _ . . . - . t . ^- - -_- - - . ( ^ I - . __fi__x___.. - . . . l . _i x. --. -. l -. - I . - - - ^- - . - , x . - - ^ , - . . - .~-n_l_l-~.--_.__~ , - _. . - . . . . - . -_. _~CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Nuruzzaman,A.K.M.1998.FloodplainFisheriesofSouthwestRegionofBangladesh.Proc.National SeminaronIntegratedManagementofGangesFloodplainsandSundarbansEcosystem,16-18 July,1994,Khulna,Bangladesh.Pp.92-111. Primavera,J.H.2000.PhilippineMangroves:ThreatsandSustainableDevelopment.AsiaPacific CooperationonResearchforConservationofMangroves.Proc.InternationalWorkshop,26-30March, Okinawa,Japan.Pp.206-220. Rahman,M.andAhsan,M.2001.SalinityConstraintsandAgriculturalProductivityinCoastalArea ofBangladesh.SoilResourcesinBangladesh:AssessmentandUtilization.SoilResourcesDevelopment Institute,Dhaka,Bangladesh. Siddiqui,A.S.M.H.1998.Sundarbansataglance.BFRI,Khulna,Bangladesh. SPARRSO.2001a.ReportonStudyonDenudationofMangroveForestDuetoShrimpFarmingUsing RemoteSensingandGISintheBangladeshCoastalRegion,2001.SpaceResearchandRemote SensingOrganization,Dhaka,Bangladesh. SPARRSO.2001b.AmanricecoverageareaintheKhulnaregionduringOctober2000(timeintegral NOAAAVHRRNDVIimagesof2,3,5,19and31October2000.SpaceResearchandRemote SensingOrganization,Dhaka,Bangladesh. SRDI.2001.SoilandWaterSalinityMonitoringReport.KhulnaBarisalDivision,1998-2000.Volume- 2(DraftReport).SoilResourcesDevelopmentInstitute,RegionalOffice,Khulna,Bangladesh. UNDP/FAOIRDP.1995.In:Canonizado,J.A.andHossain,M.A.1998.IntegratedForestManagement PlanfortheSundarbansReserveForest.GOB/WBForestResourcesManagementProjectTechnical AssistanceComponent. Wahid,S.M.1995.FinalReportonHydrologicalStudyoftheSundarbans.FAO/UNDPProjectBGD/ 84/056.IntegratedResourceDevelopmentoftheSundarbansReservedForest,Bangladesh. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m ListofPlates Plate-l:Typicalviewofshrimpfarm Plate2:Shrimpfrycollectionbyusingfinemeshnets ~~ ~-._^-.-~__I--._---t._..- .~------.---.-.----..-__._-....1-1.--.--__- ___-___I^ _~_^__________l____ .-_-__._____^__l__ ~__CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m - . . _- _I . - - . - - - - - . ____I_____Plate3:TopdyingofPalmyra palmtreesduetohighersalinity causedbyshrimpcultivation Plate4:Damage ofricedueto highersoilsalinity causedbyshrimp cultivationinthe sameland _, -i__^.--~-.-__ t-_,-_-_~~~--.IIX-..- ..~_I CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS Plate5:SoilerosionwithintheSundarbansprincipallyduetoincreased crowdingbyfishermenandfrycollectors Plate6:Rainwaterharvestinginearthenpotsduetosevere scarcityofdrinkingwater CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMSm Plate7:Soilandwatersalinitycausedseverefoddercrisisand healthproblemsinlivestock Plate8:Top-dyingofSundritreeswhichwasprincipallydueto increasedsalinityintheSundarbans _..,,.. _ ^^_^..^.-..^.^^..,... ^^.._^^-.... .^_i^^^.._.x_ _ .I...I I. ..-.---.--.-_-,-,-...^_.-~...._.-. _ -..l-.^~l.-~. .... _ .-._____ STUDIESONSUNDERBANSMANGROVEECOSYSTEMS ECOLOGYANDMANAGEMENTOF SUNDERBANSBIOSPHERERESERVE-INDIA BY SanjayV.Deshmukhl,T.AnandaRaoZ&AmaleshChoudhury3 lDirector(Research),RambhauMhalgiPrabodhini,KeshavSrushti UttanVillage,Bhayander(W),Thane401106,Maharashtra,India E-mail:drsanjaydeshmukh@vsnl.com 2Scientist-in-charge,KarnatakaAssociationfortheAdvancementofScience CentralCollege,Bangalore560001,Karnataka,India 3FounderDirector,S.D.MarineBiologicalResearchInstitute,D-44,Choudhurybari,Amarabati P.O.Sodepur,24-Paraganas(N)743178,WestBengal,India E-mail:amaleshchoudhury@hotmail.com II-------II-IIII-II--IIII--11111--II11-1111-1111111111--111111 1.Introduction Asinmosttropicalregions,mangroveswampsinIndiaisaseriouslyendangeredandvanishing ecosystem.Themainthreatcomesfromover-exploitationthroughclearfellingandland-reclamation, andthroughIndustrialpollution.Mangrovenichesoftencompeteforspaceforindustrialcomplexes, exploitingbiominingandmineralresourcesalongSeacoast,andthussubjecttoconsiderable developmentalpressures.Theusualoflandtransformationisthroughdredging,andconversionto dryland,onwhichmangrovevegetationcannotsurvive.Thisisapartfromnaturalforcessuchas stormsandhurricanes.Large-scaletransformationsalsooccurthroughsettlementscreatedbythe humans,andthroughbiomassextractionthroughstrippingofleaves,removalofsmallbranches andevenuprootingoftrees.Thesecoastalecosystemsare,however,importanttomeettheneeds oftherapidlyincreasinglocalhumanpopulation,forconservingcoastalandoffshorefishandshelf fishstocks,andforitswave-breakingandshoreprotectingproperties.Withmajorgapsexistingin ourunderstandingofthecoastalbiodiversityanditsroleinecosystemfunctioning,itisimportant thatwetakeupcomprehensiveanalysisofaBiosphereReservesuchastheSunderbansmangrove ecosystem,whichhasecologicalvalueforprotectionoftheecosystemhealthofthecoastalareas, withconcernsforthelivelihoodneedsoflocalcommunitieslivinginthearea. 2.ConservationIssues:Historical Itwasnotuntil1878thatasystemforconservationandprotectionoftheSunderbanswassetup byclassifyingforestshereasReservedandProtected.Althoughthishelpedtoprotectforeststo someextent,thosewhohadpreviouslydependedupontheresourceswerenowlegallyrestricted againstitsuse.Withtighteningofregulationsby1900thelawssurroundingforestusagebecame stricterby1900andwereextendedtoincludepoaching,althoughlocalvillagerswereallowedgun licensesforthedefenceoftheirfieldsandlivestock.Atraditioncontributingtotherapiddemiseof thegamespecieswastheshikar,oraristocratichunt.Aslargergamespecieswereheadingfor extinction,theForestServiceclosedsomeareasofftohumanusecompletely.Non-governmental organizationsincreasinglybecamemoreandmoreinvolvedinconservationissues. Withthearistocracyrealisingthevalueofconservation,thetotalauthorityheldbytheRajahs guaranteedenforcementoflaws,whichhelpedtoadeclineintheactivityofthepoachersinprivate lands.TheimplementationofCentralgovernmentlawsuponpublicforestlandswasmuchmore difficult.However,subsequenttoWorldWarIleadtoincreaseinpoaching,arisingoutofimproved firepower.WiththeintroductionofaNationalParksystem,modelleduponwesternworldperceptions, Indiaadoptedastructurethatdidnotoffersolutionsindealingwiththehumananddomesticated animalpopulationsalreadyexistingthere.ThiswastruefortheSunderbansaswell. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Resettlinghumansinthevicinityofmangrovenichesprovedtobeacriticalproblem.Inearly 19OOs,BakarganjwaschosenastheDistrictforhumanresettlement.Earlier,inthe1870s,the governmenthaddeclaredmostofKhulnasSunderbansunderthecategoryofGovernmentReserve Forest.Therefore,Khulnaremaineduntouchedbysettlers.SettlersfoundBakarganjawell-drained fertileland,lesssusceptibletotides,andsalinityproblems;therefore,by1904,Bakarganjwasover 90%settledandreclaimed(ChaudhuriandChoudhury(1994). TheSunderbansregionhaslongbeenoneofIndiaslastfrontiers,anuninhabitablethicketof mangroveswamplandseparatingtheexpandingIndianpopulationfromtheBayofBengal.The conversionofforestedlandintorice-paddysystemsbeganlongbeforetheMuslimIndo-Turkish sultansruledBengalfrom1204until1575.FollowingthisreignwasthatoftheMuslimMughals whichlasteduntil1765,followedbytheBritishrule.Theseforeigninfluences,particularlythatof theBritish,hadadverseimpactupontheSunderbanmangroveecosystem. TheWildLifeProtectionAct,1972adoptedbytheCentralandmostoftheStategovernments, bannedkillingof61endangeredspecies,providingstiffpenaltiesforoffenders,thuslayingthe legalframeworkforenforcement(Putman,1976).ANationalActionPlanforWildlifeConservation, createdin1983,providedfor:(a)theestablishmentofarepresentativenetworkofprotectedareas ensuredthatallsignificantbiogeographicregionsofthecountryarecovered;(b)providedformore scientificmanagement/restorationofprotectedareas,(c)involvinglocalpeopleinreserve managementbycombiningwildlifeprotectionwithcommunityneedsinmultipleuseareas;(d) rehabilitationofendangeredandthreatenedspecies,includingcaptivebreedingprogramsfor reintroduction;environmentalawarenessdesignedforavarietyofactorsinvolved,includingthe peoplelivinginandaroundtheparks,andthegeneralpublic;(e)researchandmonitoring. In1970,Indiahad10Parksand127Sanctuaries.TheForestConservationActof1980created moreparksandsanctuaries.By1990,Indiahad66Parksand300Sanctuaries(Sutton,1990).The objectivewasprotectionofatleast40%ofthecountrystotallandarea,equallydistributedthroughout India,toinsurethesurvivalofbothfloraandfauna.Thoughagoodframeworkforconservationis inplace,enforcementitselfisanissue. 3.TraditionalLivelihoodPatternsofLocalCommunities ExceptforthePodsandChandals,littleisknownoftheSunderbansindigenoushumanpopulation. However,temporaryfishingcampswereestablished,onislandssuchasJambudwip(Bulberry Island),everyseasoninordertoensureafreshsupplyoffishtothemarkets.Thesecampswereset upbringingfishermenfromvillages,sometimesfrompartsasfarawayasBangladesh.Although fishingwasnotregardedasbeingasworthyanoccupationaswasricecultivation,ithasalways providedanimportantsourceoffoodintheBengalidiet.Fishingalsoensuredthesurvivalofthose whowerelandless,forwhomitwastheonlypossiblelivelihood.Inanycase,livingintheSunderbans requiredagreatdealofadaptabilityonthepartofitshumaninhabitants. Withincreasingexternalpressures,theChandalintheEastandthePodintheWestmovedfrom fishingtoaneconomicactivitythatispredominantlybasedonricecultivation.Inanycase,this economictransformationalreadystartedhappeningveryearlyon;fishingwasconsideredalowly activity.InthespiritualManasa-mangalcomposedin1495byVipradas,thesnake-Goddess,Manasa, wasfirstacceptedbythecowherds,thenbythefishermen,andfinallyreceivedthepatronagefrom theBrahminpriests. Traditionallythelocalcommunitiesdependeduponfishingasaneconomicactivityformeetingtheir livelihoodneeds.DuringtheperiodoftheMuslimruleandsubsequentlyduringthetimeofthe British,therewasagradualshifttowardsagriculturepartlythroughgovernmentalincentives,and partlybecauselagoonspreviouslyladenwithfisheventuallydriedupasthemajorriverswashed depositsofsiltdownstream.By1770,landtenuresweregiventotheBengaliswhocouldreclaim landforcultivation.Cultivationincludedavarietyofcropssuchasdate.mango,coconut,arecanut, ~X. _^_. . . . . - - ^ - - - . . . _X_^-. _I -n--^. . . I _- I - - Ct . _. ^-^l l . . --. . . . - . I - . I . ^. . - - __. ; - - - ^^_.~.--.1~~--~_--1..-__.I-x--_I~~__^__~.~.._~-I_^__.____.~~~~~ CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m jackfruit,andavarietyofvegetables;however,theseweregrownmainlyforpersonalconsumption. Organizationofricefieldsleadtofurtherrefinementofaquaculturetechniqueswithsomecultivators culturingprawnsandfishinthefloodedricefields.Gradualdeteriorationofthemangroveforests overaperiodoftimeleadtotheextinctionofwildlifesuchastheTwo-hornedRhinoceros,theIndian Cheetah,theGoldenEagle,andthePink-headedDuck,allspeciesindigenoustotheSunderbans. WiththeestablishmentoftheIndianForestServicein1865,theforestdepartmentwascharged withtheresponsibilityofprofitabletimberextraction,preservationoftheremainingforests,and meetingwiththevillagerssubsistenceneeds.Thehigherauthorities,duetohighrevenuethat accruedtothegovernmentexchequer,rewardedthiscommercialfunctionoftimber.Apartfrom beingill-equippedtounderstandandmeettheneedsofresidentpeasantsandtribalsofthe Sunderbans,theroleoftheforestersinthisregardwasexacerbatedbytheircolonialmentality (Tikader,1942). 4.SunderbansasaBiosphereReserve AsapartoftheNationalManandBiosphereProgramme(MAB)oftheMinistryofEnvironmentand Forests,GovernmentofIndiaestablishedthroughanotificationin1989,theSunderbansBiosphere ReserveinWestBengal.ThecoreareaoftheBiosphereReserveispartoftheWorldHeritageSites ofUNESCO,since1989.Also,SunderbanswasincludedinUNESCOsWorldNetworkofBiosphere ReservesinSeptember2001.TheBiosphereReserve(BR)coversthelargestinter-tidalarea formedduetothemergingoftwomightyrivers-theGangaandtheBrahmaputraintheBengal basin,withacommondeltaregion,whichisoneoftheworldslargest,spreadingacrossIndiaand Bangladesh.Itisanecologicallyactivezone,thedynamicnaturebeingduetoshiftsinriverflows andriverineislandformation,coveringanareaof26,000km2. TheIndianpartoftheSunderbanscoversanareaof9630km2,withtwoDistrictsoftheStateof WestBengal,namely,24Paraganas,NorthandSouth.Spreadacrossabout102islandsofwhich,54 areunderhumanhabitation.Theyareseparatedbymanyrivuletsandtidalcreeks(Chaudhuriand Choudhury,1994).Conversionofthemangroveforestsforhumansettlementshasbeenanon- goingprocesssincethe18thcentury,whichnowcoversasubstantialarea(5430km2).Inspiteof this,largestretchesofintactmangroveforestsstillexist,aspartoftheProjectTiger,Managed since1869,theearliestmangroveecosystemthatcameundermanagement,isahabitatfora numberofendangeredspecies,notablyfortheTigerandtheSalt-waterCrocodile.Richinbiodiversity duetoavarietyofhabitats-beaches,estuaries,mangroveswamps,tidalflatsandcreaks,coastal sanddunes,etc.Withahumidtropicalmaritimeclimateandwithanannualrainfallranging between1650-1800mm,violentstormsarefrequentinthepre-monsoonandpost-monsoonperiods, whichoftenturnintocyclonesaccompaniedbylargetidalwaves. ThesoilshavetheiroriginintheGanga,Bhagirathi,aswellastheHooglyRiversystems,withGanga bringinginmuchofthesilt.Arapidphaseofgrowthofthedeltaoccurredtillthe12th century,when GangachangeditscourseeastwardsintothepresentdayBangladesh.ThisdiversionofGangainto Padmadeprivedtheforestareafromfreshwaterandhaschangedtheforeststructures.The BiosphereReservecomprisesofalluvialclay,saltandsandparticles,withsandbecomingpredominant alongtheseaface,withthreezones,namely,(a)Openseainter-tidalzone,(b)Mixedinter-tidal zone,and(c)Estuarineinter-tidalzone.Soilsareneutraltoslightlyalkalineontheislands,with organiccarbonrangingfrom0.26%-1.86%.GoodforestcoverexistsalongtheHooghly-Malta estuarinecomplex.ThemainestuariesthatrunnorthtosouthareSaptamukhi,Thakuran,Malta, Bidya,Ajmatmari,Bidyadhari,Gosaba,KalindiandRaimangal.Withanaveragetidalamplitude varyingbetween3.5to5.0m,andextensivereclamationofriverbank,thechangedtopographyhas constrictedtheareaofsiltdeposition,leadingtosedimentaccumulationintheriverbeditself,thus raisingtheleveloftheriverandmakingitmorepronetoflooding. Alongthenorth-southprofiletheimportantgeomorphicunitsare:(a)distributorychannels,(b) marginalmarshyarea,(c)tidalsandbarsandislands,(d)sub-aqueousdistalbars,and(e)pro- ~-I^___x-_~I^____.,-~- . . - ____119_. ----x~~i~ . I - ---______^.-_l_l____-~._.-_l_--~^_ll__~.._~CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m deltaclaysandsilts.Theislandsandsandbarsareperpendiculartotheshorelineandparalleltothe directionoftidalflow.ThedeltaexperiencesstrongandweaktidalcurrentsduringFebruary-May andwintermonthsrespectively.Duringthemonsoon,thedrainagepatternisdeterminedbythe interactionofheadwaterdischargeandtides.Onsuchoccasions,interestingphenomenonisthe subsidenceofpartsofSunderbanscausingdisappearanceofforestandsettlementareas. ThefollowingSanctuariesandNationalParksestablishedpriortotheformationoftheSunderbans BiosphereReserveitself,nowformanintegralpartoftheBiosphereReserve: HalidayIslandWildlifeSanctuary: HalidayIslandWildlifeSanctuary,whichislocatedonanareaof5.95km2.wasestablishedinJune, 1976.Theforestsareclassedastropicalevergreencoastalmangrove.TheforesthasCeriops interspersedwithsparsestandsofExcoecariaagallochaandPhoenixpaludosa.Ascrubbygrowthof AvicenniaofficinalisandSonneratiaapetalaoccurssporadically. SpottedDeer(Axisaxis),WildBoar(Susscrofa)andRhesusMacaque(Macacamullata)aredominant animals.Thetiger(Pantheratigristigris)isalsooccasionallysighted.Thereisabundanceoffish speciesandamongthereptiles,Cheloniamydasoccursoffshore.HalidayIslandisanestingsitefor SeaTurtlesandestuarineCrocodiles. LothianIslandWildlifeSanctuary: Thisisland,coveringanareaof38,00km2,wascreatedasasanctuaryin1948andrenotifiedin 1976.SituatedattheconfluenceofSaptamukhiandtheBayofBengal,thegroundlevelishighin thesouthernpartoftheisland,whileinnorthernareasthelandislow.Avicenniaofficinalisisthe dominantspecies,ExcoecariaagallochaandHeritierafomesaresparselydistributedandCeriopsis foundscatteredallovertheisland. SpottedDeer(Axisaxis),WildBoar(Susscrofa),andRhesusMacaques(Macacamullata)are common.Variousspeciesofwaterbirdsaresightedallyearround;migratorybirdsduringthe winterseasonarecommon..Crocodilesarefound,andtheareaprovidesanestingsiteforSea Turtles.TheBhagabatpurcrocodilefarmislocatedonLothianislandandhassuccessfullyrearedand releasedanumberofCrocodilesandSeaTurtles. SajnakhaliWildlifeSanctuary: Sajnakhaliwildlifesanctuarycoversanareaof362,40km2.Declaredasasanctuaryin1960and laterre-notifiedin1976,thissanctuaryfallsunderthejurisdictionofProjectTiger.Theforestcover consistsofscrubsofCeriops,mixedwithstuntedExcoecaria.TherearesomeSonneratiaapetala, XylocarpusgranatumandXylocarpusmekongensis,andthicketsofPhoenixpaludosaintheupper intertidalregion,whileAvicenniaofficinalisisobservedalongthebanksofcreeksandrivers. Sajnakhaliwaslongrenownedasabirdsanctuaryandhasremainedanimportantbreedingsitefor manyyearsforseveralspeciesofmigratoryandresidentbirds.Allthewildlifespeciesfoundinthe Sunderbansoccur,exceptfortheSeaTurtles. ProjectTigerNationalPark: AlarmedbythesteepdeclineintheTigerpopulation,(Pantheratigristigris)killingofTigerswas prohibitedin1970,followedbyabanonallhunting.Acountrywidetigercensusin1972revealed thatthespeciescountwasdowntolessthan2,000,analarmingdeclinefromanestimated40,000 attheturnofthepresentCentury.ArmedwithWildlifeProtectionAct,1972,ProjectTigerwas launchedin1973.Presentlythereare18TigerReservesin13Statesacrossthecountry,covering atotalareaof28,017km2 with12,634km2 aspartofthecore.ProjectTigerisacomprehensive collectiveprogrammewithprotectionaffordedtoTigerpopulationwithinthenaturalecosystem, takingintoconsiderationthelivelihoodneedsoflocalcommunitieslivingincloseproximity. CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m TheSunderbansProjectTigerinitiallystartedin1973covered2585km2ofareawithacoreof1,330 km2,withanadditional241km2demarcatedasasubsidiarywildernesszone.Thecoreareawas laterdeclaredasaNationalPark.UndertheoverallsupervisionofaFieldDirector,thenumberof TigersintheSunderbansProjectTigerareaincreasedfrom205to251intheyearbetween1979- 1993,thoughtheexpertsintheareaexpresssomedoubtsaboutthenumbers.Thecoreareaof ProjectTigerwasdeclaredaNationalParkin1989.Thepristinewildernessofthisareaandthe importantroleitplaysinthesurvivaloftheBengalTigerhasearneditUNESCOsrecognitionasa WorldHeritagesite. 5.EcologicalandBiodiversityAttributes: Ecologicalcharacterization: MangrovesofSunderbanscoveranareaofapproximately400,000hectaresofforestofmosaic systemgradients,reflectingdifferenttypesofadaptiveradiationsinfauna1andfloraldiversity.The recentworkonthemangrovesofthefloralandfauna1taxaofthemangrovehabitatsoftheSunderbans byChaudhuriandChoudhury(1994)isanimportantcontributiontoconservationofmangrove systems. Mangroveformationisauniquetropicalphenomenon,whichisuniquefortheirsurvival.Apartfrom externaladaptiveandinternalstructuralfeatures,physiologicaladaptationistotoleratesalinity stressandsurviveinwaterloggedanaerobicsoil. Classificationofthemangrovesystem: Overtheyears,manyworkershaveattemptedtocategoriestheforesttypesoftheSunderbans baseduponasystemofclassification,mostlyonphysiognomy,climateorinundationlevels.Prain (1903)dividedtheentireSunderbansintothreezones,namely(i)southerncoastalstripand South-westernpartconsistingofmangrovespecies,(ii)centralzoneofHeritierafames,and(iii) north-easternpartofSavannahtypevegetation.TheIndianSunderbansfallsinthefirstcategory, withmanydifferentspeciesatdifferentlocations(Box1). Box1.Diversityinspeciescompositionatdiversehabitats(Prain,1903). I 0Freshmud-bandofrivers:Sonneratiaapetala. 0 I Banksoflargerrivers:Bruguieragymnorrhiza,Ceriopsdecandra,Kandeliacandeland Rhizophoramucronata. 0Banksofsmallercanals:Aegicerascorniculatum,Cerberaodollam,Dalbergiaspinosa, Phoenixpaludosa,SonneratiacaseolarisandXylocarpusgranatum. 0Banksofnarrowchannels:AegicerascorniculatumandBrownlowiatersa. (!Banksofnarrowestchannels:Nypafruticans. Troup(1921)stressedthatcertainedaphicfeaturespreventthedevelopmentoftheclimaticclimax, andtheavailablevegetationtypesintheBiosphereReserveatbestcouldbeconsideredasedaphic climaxonly,theobviousexamplesbeingthemangrovetidalforestsoftheestuarineecosystems. However,theclassificationofCurtis(1933)isbasedoneco-physiologicalcharacteristicsofthe floristiccompositionoftheSunderbansforests.HedividedtheSunderbansintothreemangrove foreststypes:(i)freshwaterforest,(ii)moderatelyintensesaltwaterforest,and(iii)saltwater forest,withdiversespeciescomposition(Box2). Champion(1936)classifiedthetidalforestsunderprimaryseraltypeofmoisttropicalseralformations anddidnotregardthemangroveasaclimaxorpre-climaxforesttypes.Hedividedtheforestsof . - ; . , . - . - . . _. . . _. - _. . . ^ . , t_._. ^. . ^ _1 . - - . . ^ . - . - . - , . ~ n__ . . _ . . . , ._-. . . . x . , - - - - _ , . _. - - - . - . , . . . . _.. . - . . , .^~^. I - _ . . . , . ~. . . . ._i__ _,~ . . - - . - ~. _- _ ^ .CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m Box2.Speciescompositionbasedonsalt-toleranceofmangrovespecies 0Freshwaterforest:Amooracucullata,Ceriopsdecandra,Cynometraramiflora,Heritiera fomesandXylocarpusgranatum. 0Moderatelysaltwater:Bruguieragymnorrhiza,Ceriopsdecandra,Excoecariaagallocha. SonneratiaapetalaandXylocarpusmekongensis. 0Saltwaterforest:Acanthusilicifolius.Aegialitisrotundifolia,Avicenniaofficinalis, Excoecariaagallocha.Rhizophoraapiculata,SonneratiaapetalaandXylocarpusmekongensis. theSunderbansregioninto: a)Mangroveforestsconsistingof(i)Lowmangroveforestand(ii)Treemangroveforest,and b)Heritierafomesforestconsistingof(iii)saltwaterHeritierafomesand(iv)freshwaterHeritiera fomesforest. TheIndianSunderbansfallundercategories(i)and(ii)whiletheSunderbansforestsinBangladesh areconsideredtoberepresentativeoftypes(iii)and(iv)(ChaudhuriandChoudhury,1994). ChampionandSeth(1968)madeoneofthemostcomprehensiveassessmentsofthevegetation communitiesoftheIndianSunderbans.Theydividedtheforestintocategoriesbasedonbroad characteristicsofphysiognomyandstructure.Thecommunitiesweredefinedirrespectiveof physiographic,edaphicorbioticfactors,thoughsomecommunitiesmaybeclearlyassociatedwith definitesitefactors.Twotypesofforests,namelylittoralforestsandtidalswampforestswere recognized,eachwithdifferencesincomposition(Box3).ChaudhuriandChakraborty(1973a, Box3.Vegetationcompositioninlittoralandtidalswampforest(ChampionandSeth,1968). A.Littoralforestsextendoveralimitedarea: 0ClassI:WithspeciessuchasDolichandronespathacea,Erythrinavariegata,Hibiscustiliaceus Ixoraaraborea,Tamarixtroupii,Thespesia,populnea,Trewianeudiflora,Vitexnegundoand Vitextrfolia. 0ClassII:comprisedofAcanthusiliciflius,Crotolariaspp.Lippiageminata,Porteresiacoarctata andSaccharumsponteneusm. B.Tidalswampforestsinundatedbyhightides,whichcomprisefollowingmangroveforests: a.MangrovescrubforestwithClassIandClassIicomprisedofspeciessuchasAegialites rotundifolia,Avicenniaalba,Ceriopsdecandra,ExcocecariaagallochaandPhoenixpaludosa andClassIVcomprisedofAcanthusilicifoliusandBrownlowialanceolata. b.MangroveforestcomprisingofAvicenniaalba,Bruguieragymnorrhiza,Ceriopsdecandra, Ceriopstagal,Excoecariaagallocha,Kandeliacandel,Lumnitzeraracemosa,Rhizophora mucronata,Rhizophoraapiculata,Sonneratiaapetala,XylocarpusgranatumandX. mekongensis. c.SaltwatermixedforestcomprisingofAegialitesrotundifolia,Amooracucullata,Avicennia officinalis,Bruguieragymnorrhiza,Ceriopsdecandra,Excoecariaagallocha,Heritierafomes, XylocarpusmekongensisandNypafruticansandfinally. d.BrackishwatermixedforestwithclassIcomprisingofAvicenniaofficinalis,Bruguiera gymnorrhiza,Heritierafomes,Sonneratiaapetala,S.caseolarisandXylocarpusmekongensis. ~~~xI_~--_I CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m 1973b,1973c)dividedtheMangroveforestintofourtypesbasedontidallevelas(i)hightide,(ii) abovegeneraltidelevel,(iii)frequentlyinundatedbysaltwaterand(iv)belowtidelevel. AccordingtoBlasco(1975),thespatialzonationsuggestedbyChampionandSeth(1968)isnot practicalbecauseitdoesnotconsidertheanthropogenicandbioticfactors(Box4).Sidhu(1963) pointedoutthatasaresultofconstantbioticinterferencespeciesofAcanthusandAvicennia generallyoccupytheaffectedregionsaspioneerspecies. Box4.Spatialzonationofvegetationbasedonanthropogenicandbioticfactors(Blasco,1975). 1 Back-mangrove(Euhalinezone)foundontheriverbank,consistingofClerodendrum enerme,Salicorniabrachiata,Sesuviumportulacastrum,Suaedamaritime,S.nudiflora, AegialitisrotundifoliaandAegicerascorniculatum. Densemangroveconsistingofvariousspeciesofplants.Onehectaremaycontain12 treesoflo-15mheight,440shrubsof4-8mheightand2,200ofundergrowth measuringlessthan4minheight. Tall,densetreesofHeritierafomeswiththeirprimaryassociateExcoecariaagallocha. BrackishwaterofmixedHeritierafomesforestwithRhizophoraspeciesoveravery limitedarea. PalmswampsconsistingofpurePhoenixpaludosa. NaskarandGuhaBakshi(1982)groupedtheforestsintofivemajorzonesas:(i)Sea-faceorbeach forest,(ii)formativeislandflora,(iii)floraofreclaimedlandandlow-lyingareas,(iv)floraof riverbanksand(v)swampforest.Psammophyticplantsduetothedrynessofthesandysoilhere dominatethefirstcategory,withmanydunes.Thefloraoftheformativeisland:sconsistsmainlyof Porteresiacoarctata,Suaedamaritima,Suaedanudiflora,Phragmiteskarka,Acanthusilicifolius, andafewtreespeciessuchasAvicennia,SonneratiaandExcoecariaspp.Thereclaimedareasare dominatedbymesophyticflora,whilstthelasttwozonesdominatedbyhalophyticspecies. ChaudhuriandChoudhury(1994)haverecorded36speciesofEumangroves(realmangroveswith clear-cutadaptivefeatures),25speciesofmangroveassociatesoftheobligatorykind,andmany facultativetypesandafewEuhaline(generallyrockyandsandysubstratumwithsalinityranging from30to40ppt)species.Adetaileddescriptionofthesespeciesobservedin22forestblocks alongwithenvironmentalparametersandtheassociatedbiotaisalsoprovidedbythem. RecentlyRaoandSuresh(2001)haveintroducedamorerealisticclassificationforthemangrove species,astheyexistinnaturetosortouttheiroccurrenceasasystemofgradientsunderthree categories.Eumangrovesaretherealmangroveswithclear-cutadaptivemorphologicalfeatures bothexternalaswellasinternal.Theyhaveviviparousmodeofgermination,pneumatophoresof differentshapesandsizes,aerialrootswithlenticelsandfoliarglands.Internally,theyhavexeric featuresandidioblastsofdifferentcategorieslike,crystals,tannins,sclereids,etc.,whicharevery helpfulasanaidtodiagnosethespecies.Innature,unlessnotdisturbed,mangrovesoccurinstrips correspondingtothesalinitylevels,withspecificityfordifferentmangrovetaxa(Box5). CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m -..._. Box5.Ahabitatgradientlinkedclassificationofmangrovevegetation(RaoandSuresh,2001). 0Eumangroves:Acanthusilicifolius,A.volubilis,Aegicerascorniculatum,Aegialitis rotundifolia,Avicenniaalba,A.marina,A.officinalis,Bruguieracylindrica,B.gymnorrhiza, B.sexangula,B.parviflora,Ceriopsdecandra,Excoecariaagallocha,Kandeliacandel, Lumnitzeraracemosa,Rhizophoraapiculata,R.mucronata,Sonneratiaapetala,S.caseolaris, Xylocarpusgrannatum,X.mekongennsis. Thesecondcategoryofmangrovevegetationcomprisesofmangrove-associatedbiota.They areoftwotypes:obligatoryorfacultativeassemblyofspecies,toleratingdifferentdegrees ofsalinityinthemangrovehabitat.Theobligatorytypesareallsalttolerantplantswithout anyexternal,spotcharacters.TheiroccurrenceinSunderbansareaismoreintermsof speciescounts.Theothertypeofspeciesassemblybelongstothefacultativecategory whereecologicalamplitudeofthespeciesextendsfromcoasttoinland.Theythrivewell undersalineornon-salinesoils.Basedonthisview,theSunderbansmangroveflorais categorizedbelow: 0Mangroveassociates(Obligatorytypes):Amooracucullata,Brownlowiatersa,Cerbera odollam,Cynometraramiflora,Dalbergiaspinosa,Derrisscandens,D.umbellatum, Dolichandronespathacea,E.bicolour,Finalaysoniaobovata,Heritierafomes,Hibiscustiliaceus, H.tortuousus,,Nypafruticans,Phoenixpaludosa,Tamarixdioica. 0FacultativeTypes:Avicennialanata,Ammanniabaccifera,Caeslpiniacrista,Canavalia catharitica,Cyperusexcaltatus,Fimbristylishalophia,FimbristylisSub.bispicata,Heliotropium curassavicum,Hoyaparasitica,Panicumrepens,Paspalumvaginatum,Phragmiteskarka. 0Euhalinemangroves:Salicorniabrachiata,S&pustriguetra,Suaedamaritima,S.nudiflora Aleuropuslogopoides,Myriostachyawightiana,Porteresiacoarctata,Sarcoboluscarinatus, Sesuviumportulacastrum. Biodiversityissues: TheSunderbansBiosphereReservehas36truemangrovespecies,28mangroveassociatesand7 obligatorymangrovespecies.Phoenixpaludosadominatestheregionwithlesstidalinundation; elsewhereassociationofCeriopsdecandraandExcoecariaareseen.AlongriverbanksAvicenniaand Sonneratiaareseen.Theotherspeciesarefoundscatteredwithintheforest.ChampionandSeth (1968)dividedtheforestareasofSunderbansintotwodivisionsasLittoralforestandTidalSwamp forest.NaskarandGuhaBakshi(1982)haveclassifiedtheforestintofivezonesas:Seafaceor beachforest,Formativeislandflora,Floraofreclaimedland,FloraofriverbanksandSwampforests. NaskarandGuhaBakshi(1987)haveenumeratedangiospermsfromthelowerGangaDelta;Mandal andNandi(1989)havecompiledanexhaustivelistoffauna1elementsfromPoriferatoMammalsof Sunderbans. XylocarpusgranatumandXylocarpusmekongensis,whichwereonceverycommonmangrove speciesoftheSunderbans,arenowsparselydistributedduetopoorregenerationafterfelling. ThereisabanonfellingofNypafruticans;theonlyotherareawherethisspeciesisfoundtooccur naturallyisAndamanIslandintheIndiansubcontinent.Basedonthepresentstatus,themangrove speciesthatrequireimmediateconservationmeasureshavebeenidentifiedas Aegicerascorniculatum, Heritierafomes,Kandeliacandel,Nypafruticans,Rhizophoramucronata,Rhizophoraapiculata, Sonneratiaalba,SonneratiaapetalaandSonneratiacaseolaris. Table1highlightsthedistributionofplantspeciesexclusivetomangrovehabitatsofSunderbans withrespecttotheirlocationintheinter-tidalregion. ~~-~ _xl-_________---~~~-.~.~---~~-~~--- - , - - . - - . _- _^~~- CASESTUDIESONSUNDERBANSMANGROVEECOSYSTEMS m