再谈关键是要取得实效摘要关键词：长江水质;高锰酸盐指数;氨氮浓度;水环境容量;AbstractThisthesisexplorestheevaluationandforecastofthewaterqualityofYangtzeRiver.Thegeneralevaluationofwaterqualityandthepollutionsituationofrelatedregionsareconcludedbyanalyzingtheattachmentqualitativelyaswellasquantitatively.Firstly,bybuildingthewaterqualitymodeltoneglectthedispersioncoefficientofone-dimensionalsteadystate,wecancalculatetheindexofCODMnandthemainregionpollutedgreatlybyNH3-Nrespectively.Then,byanalyzingthepollutionatthebranchandlocalregion,wecanfindtheorigin.Intherespectoftheforecastforthedevelopmentinthefollowingtenyears,weadoptthemethodofline-fittingprocessandleastsquarestoanalysisandsolve,sowecanmasterthetrend.And,intherespectofdisposalofthepollutedwater,weadoptthemodelofcalculatingthecapacityignorantofthemixedarea,sowecansolvetheproblembybuildingnewmodel.Finally,accordingtotheresultofstatisticsanalysis,weputforwardthereasonableproposalandsuggesttosolvetheproblemoftheproblemofthewaterpollutioninYangtzearea.Keyword：FluidmatterofYangtzeRiver;soursaltindexnumberofhighmanganese;theammonianitrogendensity;environmentcapacityofwater
