Soil Erosion Risk Spatiotemporal Changes and Predictions Under Multiple Development Scenarios: A Case Study of the Weihe River Basin

Soil erosion resulting from alterations in land use on the Loess Plateau has long impeded high-quality economic growth and ecological preservation. The continuously increasing land transfer intensity in recent years has also posed additional ecological risks within the Weihe River Basin (WRB). Therefore, in response to the lack of spatiotemporal coupling simulations under various future scenarios, we construct a coupled framework integrating the Patch-generating Land Use Simulation (PLUS) model and the Chinese Soil Loss Equation (CSLE), and conduct quantitative, spatiotemporally explicit simulations and validation. The results from 2000 to 2020 indicate 4662.47 km2 decrease of agricultural land and 45.51% increase of construction land in the WRB; more than 70% of the basin was micro-mild erosion while strong and extremely strong erosion was distributed in the north Loess Hills and southwest Qinling Mountains. The strong and extremely strong erosion area increases more than 550 km2 by 2030 under Agricultural Protection (AP) scenario, but by more than 200 km2 decreases by Sustainable Development (SD) scenario, indicating the effective effect by optimizing land structure along with ecological protection. This study demonstrates the significant impact of land use alterations under various development models on erosion risk. The present study highlights that the SD scenario can efficiently suppress increasing trend of worsening erosion. Compared to traditional static or single-model approaches, the spatially explicit multi-scenario coupling framework better captures the dynamic feedback mechanisms between land use change and soil erosion processes.