简介：

简介：

简介：ValuatingthefunctionofecosystemservicesiscrucialforaccountinggreenGDP,makingaconserva-tionpolicyofecologicalenvironmentandthedecisionofregionaldevelopmentaswellassustainabledevelopmentstrategy.Rice-duck-fishsymbiosishasbeenpromotedinseveraldevelopingcountriesasawayofincreasingincomesforricefarmers,butinvestigationsofitsvaluehavemainlyfocusedondirecteconomicbenefits,suchasfoodandrawmaterialproduction.Fewstudieshavebeenconductedontheestimationofindirectservicesprovidedbyrice-duck-fishcomplexecosystem.Thegasregulationserviceanditseconomicvaluesprovidedbyrice-duck-fishcomplexecosystemwerestudiedinWuhan,China.ThemajorcomponentsofgasregulationareO2emissionandgreenhousegases(GHGs,CO2)regulation.TheresultsshowthatO2emissionfromdifferenttreatments(includingrice-duck(RD),rice-fish(RF),rice-duck-fish(RDF)andrice(CK))rangedfrom26,370kg/hato33,910kg/haperyear,withaneco-nomicvalueof10,050-12,920yuan/haperyear(Chinesecurrency:1euro=10.2475yuan,August28,2007).ThenetGHGsexchangevariedfrom1,200to3,320kg/haperyear,anditseconomicvaluerangedfrom1,040yuan/hato2,900yuan/haperyear.Consequently,thetotaleconomicvalueofgasregulationprovidedbysymbiosiscomplexecosystemsrangedfrom11,090yuan/hato15,820yuan/haperyear,andthemaximumoveralleconomicvalueofgasregulationwasprovidedbyRDFcomplexecosystem.Theworkwillbeusefulforfurtherunderstandingofthefunc-tionsofrice-duck-fishcomplexecosystemservicesandsupplyingthetheoreticalreferencestoagriculturalpolicy.