1、中國科學院教育部水土保持與生態(tài)環(huán)境研究中心碩士學位論文基于GIS的黃土高原延河流域土壤侵蝕時空動態(tài)評價姓名：汪邦穩(wěn)申請學位級別：碩士專業(yè)：土壤學指導教師：楊勤科20070501ABSTRACTVSpatiotemparilyAssessmentofSoilLoessinYanHeRiverBasinonLoessPlateauBasedonGISRUSLEStudent：BangwenWangSuperviss：QinkeYangMaj

2、:SoilScienceResearchfield:GISapplytosoilerosionABSTRACTSoildegradationisoneofthemostdisastrousenvironmentalproblemsthreateningthesustainabledevelopmentofhumanbeingsespeciallysoilerosionwhichhasbeenregardedasthemostsevere

3、environmentalprobleminChina.Therefesoilwaterconservationmeasureshavebeengivenmuchattentionbynationallocalgovernmentsinstitutestheirprojectshavebecomethebackboneoftheecoenvironmentconstructioninareassufferingfromsoilwater

4、loss.Regionalassessmentofsoilwaterlossisthenextlogicalstepinimpactassessmentresearchafteranalyzingslopelevelwatershedscale.Regionalassessmenthasmefarreachingimplicationsfpolicydecisionsatmacroscalequantitativestudiesofso

5、ilwaterlossatregionalscalefuturelsurfacedistribution.ThisstudyisdoneintheYanHeriverwatershedlyinginthedleoftheLoessPlateau.IntheresearchtheRUSLEmethodwasusedwhichhasassessedwatersoillossduetoconversionoffarmltofestgrassi

6、nthisareabefe.TheprinciplesusedinthisresearcharebasedonthetheiesofsoilerosionphysiognomyenvironmentstatisticsecologymakinguseofRSGIStechniques.Followingaresomeconclusionsoftherept:1)Byanalyzingvalidatingthisstudyedamathe

7、maticalmethodwhichwasadaptedtotheLoessPlateaufabstractingslopeslopelengthfactvalue.TheseabstractedvaluescanbeusedasthegeographicfactoftheRevisedUniversalSoilLossEquation.WhenusingthefmulafromtheRUSLEmodeltoassesswatersoi

8、llossintheYanHeriverwatersheddirectlyitisdifficulttoguaranteeaccuracyfabstractingslopeslopelengthfromthecomplicatedgeographyonLoessPlateau.Comparedwithafmerresultvalidatingsamplesvalueswithmeasuredvalueswhichwereatthesam