Simulation Effect Analysis of RUSLE Model on Slope Soil Erosion Restored by Reclaimed Vegetation in Loess Plateau

[Objective] To explore the effectiveness of the Revised Universal Soil Loss Equation (RUSLE) model in simulating soil erosion on slope surfaces during vegetation restoration in the Loess Plateau. [Methods] This study utilized rainfall-runoff and sediment data from ten runoff plots in Ansai Fangta small watershed in northern Shaanxi Province during 2016—2022. Utilizing various commonly used algorithms for RUSLE model factors specific to the Loess Plateau, a total of 144 combinations of factors were simulated to estimate soil erosion on restored slopes. The Nash-Sutcliffe efficiency coefficient (NSE) and root mean square error (RMSE) were used to evaluate the effectiveness of the model simulations. [Results] The results indicated that the simulated soil erosion on restored slopes using the 144 factor combinations ranged from -38.47 to 0.19 for NSE and from 1.92 to 12.65 t/(hm2·a) for RMSE, suggesting limited model performance. The selected algorithms for RUSLE model factors appeared to be inadequate for assessing soil erosion on slopes undergoing vegetation restoration. Further improvements are needed for the individual factors within the RUSLE model. When applying RUSLE model to simulate soil erosion on restored slopes in the Loess Plateau, it is recommended to utilize data with high temporal resolution to reduce errors in calculating the R-factor, and comprehensively consider the effects of soil physical and chemical properties such as soil organic matter content, soil particle size and aggregate structure and bulk density on K-factor, and the the effects of vegetation coverage, vegetation height, litter, and biological crust and C-factor, full consider to slopes steeper than 10° in refining the LS-factor. [Conclusion] The RUSLE model is not well-suited for simulating soil erosion in the context of vegetation restoration on abandoned slopes in the Loess Plateau.This study provides some reference for the research and development of soil erosion model and the application of RUSLE model on the slope of vegetation restoration in the Loess Plateau.