Geoderma285(2017)260–269 ContentslistsavailableatScienceDirect Geoderma journal homepage: www.elsevier/locate/geoderma Combinedsoil-terrainstrati?cationforcharacterizingcatchment-scale soilmoisturevariation DougBaldwina,KusumJ.Naithanib,HenryLinc,? a DepartmentofGeography,ThePennsylvaniaStateUniversity,UniversityPark,PA,16802,USA b DepartmentofBiologicalSciences,UniversityofArkansas,Fayetteville,AR,72701,USA c DepartmentofEcosystemScienceandManagement,ThePennsylvaniaStateUniversity,UniversityPark,PA,16802,USA a r t i c l e i n f o a b s t r a c t Articlehistory: Received29April2015 Receivedinrevisedform8September2016 Accepted25September2016 Availableonline17October2016 Soilpropertiesandterraincharacteristicsin?uencespatiotemporalpatternsofsoilmoistureacrossawatershed. Toimprovethepredictivepoweroflandscapehydrologicmodels,itisessentialtoconsiderbothsoilandterrain attributeswhenstratifyingacatchmentintosimilarhydrologicfunctionalunits.Inthisstudy,wedevelopedand validatedanewcatchment-scalestrati?cationschemefortheShaleHillswatershedbycombiningsoilandterrain attributesinanattempttodelineatesoil-landscapeunitswithsimilarsoilmoisturedynamics.Terrainwascom- binedwithsoilsinformationby?rstusingaRandomForestsupervisedclassi?cationalgorithmtopredictade- tailed soil map using 47?eldsoilsamples andterrain variables derived from 1-mLiDAR. Aslope class map generatedfromtheLiDAR-deriveddigitalelevationmodel(DEM)wasoverlaidonthepredictedsoilmaptode- lineateareasofsimilarslopevalueacrossthecatchment.Wecomparedtheperformanceofthisnewstrati?cation schemewithtwoclassicalstrati?cationschemes,asoilmapdevelopedfromdetailed?eldsurveyandalandform unitmapbasedontheDEM,forestimatingsoilmoisturetime-seriesacrosstheforestedwatershed.Thecom- binedsoil-terrainmethodoutperformedclassicalstrati?cationschemesinestimatingsoilmoisturetime-series overa4-yearperiod.Ourresultsdemonstratethatcombiningsoilandterrainattributescanhelpimprovethe strati?cationofacatchmentintosimilarsoilhydrologicfun