Comparison of Two RUSLE Models at the Hillslope Scale in Experimental Plots in Haiyuan, Ningxia, China

Abstract Topsoil erosion and mass soil losses from hillslopes have negatively affected water quality, vegetation health, local ecosystems, and livelihood. Studies have stated the effectiveness of vegetation in significantly reducing top-soil erosion and enhancing slope stability. This study aims to better understand the application of erosional models in Haiyuan of Ningxia, a semi-arid region of China. The study site is comprised of 20 experimental plots with 11 vegetation covers and 5 slope gradients in design, which were compared to the benchmark of bare land with each slope gradient. Meteorological data and soil hydraulic measurements were collected from 2005 to 2012, and runoff and sediment load were measured by concrete basins at the base of the slopes, which mainly occurred during the summer storms. Multi-plots provide different combinations of vegetation covers and slopes to identify the driving factors of topsoil erosion during rainfall-runoff events and to examine the threshold behavior of their inter-relationship. In order to determine which models were most applicable to this area, the results of RUSLE and CSLE were applied to the data and compared to the known results.