简介：

简介：Preferentialflowistheordinaryphenomenonofrapidandnon-equilibriumtransportofwaterandsolutesoccurringinmostsoil.Itcauseslatentpollutionofgroundandsurfacewatersandaffectsrunoffyieldandflowconcentration.ThispaperstudiespreferentialflowforadarkconiferousecosystemintheupperreachareaoftheYangtzeRiver,establishesaclassificationforthepreferentialflowanddiscussestypesofpreferentialflowwithasoilcolumnexperimentusingahomemadeapparatusanddye-traceranalysis.Thepreferentialflowismainlyunsaturatedgravitationalflowintheupperlayeroftheslopedepositformatureforestsoil,whichisdominatedbyawetnessfront,andtheflowgraduallytransformstomacroporousflowasthesoillayerdeepens.Theobservedpreferentialflowintheyoung,middle-agedandover-matureforeststhathavegrownonglaciallateralmorainesismacroporousflow.ThepurposeofthisresearchistoanalyzesystemicallythebehaviorofsoilwatermovementforadarkconiferousforestecosystemintheupperreachareaoftheYangtzeRiverandtoprovideatheoreticalbasisforeffectivewatershedmanagement.