Modeling of sand production and transport on wind-water composite erosion slopes based on energy processes

Soil erosion is most intricate and damaging in the geomorphological context where wind and water erosion converge. This research introduces an energy-based model for simulating wind-water composite erosion, sand generation, and sediment transport on sandy and coarse sandy slopes within the Yellow River basin. The model integrates erosion energy as a fundamental element, utilizing data obtained from wind tunnel testing and rainfall studies. The findings indicate that the wind erosion energy-based model for predicting sand production and transport is highly effective in sand-capped bedrock, sand-capped loess, and loess regions, achieving coefficients of determination ( R 2 ) of 0.978, 0.944, and 0.979, respectively. The goodness of fit between sediment yield on loess slopes and runoff erosion energy yielded an R 2 of 0.804, whereas the R 2 for sand-capped slopes was only 0.565, indicating a significant decrease in fitting performance compared with loess slopes. The wind-water compound slope erosion sediment yield and transport model established in this study achieves coefficients of determination R 2 of 0.891 for sand-capped loess and 0.957 for sand-capped bedrock, and possesses better prediction performance than models that only take runoff energy into account. This research not only provides theoretical support for the in-depth prevention and control of combined wind and water erosion, but also offers quantitative evidence for formulating regional ecological restoration and management strategies.