中国农业面源污染形势估计及控制对策__中国农业面源污染控制中存在

EstimationofAgriculturalNon-PointSourcePollutioninChinaandtheAlleviatingStrategies.AReviewofPoliciesandPracticesforAgriculturalNon-PointSourcePollutionControlinChinaZHANGWei-li1,XUAi-guo1,JIHong-jie1,KOLBEH.2(1SoilandFertilizerInstitute,ChineseAcademyofAgriculturalSciences,Beijing100081;2SächsischeLandesanstaltfürLandwirtschaft,Gustav-Kühn-Str.8,D-04159Leipzig)Abstract:CurrentpoliciesandprojectsimplementedforcontrollingwaterpollutioninChinawerereviewed.Themainproblemisthatthecontrollingprosecutionhasbeenmainlyconcentratedonend-controlengineeringprojectssuchasestablishmentofsewagefarmandartificially-builtorreclaimedwetlandatbayouorwatercourse,eveninthewatershedswhereagricultureistheleadingcontributortowatereutrophicationofthewatersystems.Becauseoflackingofsource-controlpoliciesandtechnologiesforreducingpollutantsresultingfromagriculturalactivities,croppingareasforvegetable,fruittreeandflowercropswithextremelyhighnitrogenandphosphorusfertilizationincreasedrapidlyinsensitiveregionsofwatershed.Thecontinuingincreaseoffertilizeruseandanimalbreedinginruralareaofimportantwatershedsmakesitevenmoredifficultinfuturetorestorealreadyheavilyeutrophicaquaticecosystems.Tosolvetheproblems,itwassuggestedthattheproperregulationstoconfineenvironment-unfriendlyagriculturalactivitiesshouldbeestablishedandimplementedindifferentwatershedsassoonaspossible.Theconventionaltechniquesshouldbereplacedbymoreenvironment-friendlyalternatives.Sincechangesoflanduseformandtechnologiesmightresultinincomelossesoffarmersinruralregion,effectivenessofsuchsource-controlpoliciesdependsgreatlyonthattheimplementedregulationsandtechniquesshouldbeapprovedwithhighfinancialandsocialfeasibility.Toimproveefficiencyofthesource-control,detailedresearchworkstounderstandmainreasonsandgeneratingmechanismsofnon-pointsourcepollutionfromagricultureshouldbecarriedoutinwatersheds.Accordingtolocalclimate,hydrological,geological,topological,soilandagriculturalproductionconditions,waterprotectionzonesofdifferentgradesshouldbedefined.Correspondingtothesensitivitiesofdifferentzonestoaquaticecosystem,therelatedtechnicalstandardsforlanduseform,treatingexcrementsfromanimalstall,fertilizing,plowing,pesticidespraying,irrigationandrotationshouldbedraw.Inwatershedswithheavyagriculturalnon-pointsourcepollution,subsidytofarmersmightbenecessaryinordertoencourageawide-spreadapplicationofenvironment-friendlyalternativesinthewholewatershed.Keywords:Classificationofnon-pointsourcepollution;Watershedmanagement;Technologicalstandardsforagricultureproductioninwaterprotectionzones···References