Original paper

Modeling Soil Erosion and resulting Sediment Transport into Surface Water Courses on Regional Scale

Schindewolf, Marcus; Schmidt, Jürgen; von Werner, Michael

Abstract

The event based soil erosion simulation model EROSION 3 D is applied on regional scale for the federal state of Saxony/Germany. This study aims to simulate soil loss, deposition and sediment transport into surface water bodies for a 10 years storm event and three land use scenarios. Based on available region-wide geo-data the EROSION 3 D model is parameterized using the DPROC interface. This software has been developed for semiautomatic parameterization of large areas. The basis of parameterization is a relational data base consisting of measured EROSION 3 D model parameters, which have been derived by rainfall simulation experiments. The regional scale simulations identify the Saxonian Loess Belt as hotspot of soil erosion. However considerable amounts can also be expected also in certain areas of the low mountain range. Main sediment delivery areas correspond to hotspots of soil erosion. Amounts of erosional soil losses and transported sediments can be reduced by 92% with changes in soil management (conservation tillage measures, compared to Worst-Worst-Case-conditions). Taking into account real land use and tillage practices reduction in soil loss amounts to 88% related to the Worst-Worst-Case-scenarios. Concerning comparisons of EROSION 3 D and USLE or PESERA results the spatial distribution of soil losses in the Loess Belt matches well. Qualitative and quantitative deviations are caused by differing model approaches as well as input data. Since USLE and PESERA are focused on long term estimates, these models disregard maximal rainstorm impacts. Soil erosion is a highly non continuous process, so that maximal impacts are mainly significant. Only event based models as EROSION 3 D are able to take account of extreme rainstorms adequately. Based on this paper environmental and agricultural planning authorities obtain precise information on the spatial distribution of soil loss and deposition as well as on sediment transport into surface water courses that allow solid planning like dimensioning of soil and water conservation measures.

Keywords

soil erosionsedimenterosion 3 ddprocuslepeseraprocess based modeling pesera