Soil erosion analysis in a small forested catchment supported by ArcGIS Model Builder

摘要

To implement the analysis of soil erosion with the USLE in a GIS environment, a newworkflow has been developed with the ArcGIS Model Builder. The aim of this four-part workflow isto accelerate data processing and to ensure comparability of soil erosion risk maps. The first submodelgenerates the stream network with connected catchments, computes slope conditions and the LS factorin USLE based on the DEM. The second submodel integrates stream lines, roads, catchmentboundaries, land cover, land use, and soil maps. This combined dataset is the basis for the preparationof other USLE-factors. The third submodel estimates soil loss, and creates zonal statistics of soilerosion. The fourth submodel classifies soil loss into categories enabling the comparison of modelledand observed soil erosion. The workflow was applied in a small forested catchment in Hungary.Although there is significant deviation between the erosion of different land covers, the predictedspecific soil loss does not increase above the tolerance limit in any area unit. The predicted surface soilerosion in forest subcompartments mostly depends on the slope conditions.