Soil erosion risk and prediction under land use changes based on RUSLE and PLUS models in the black soil region of Northeast China

Land use changes caused by human activities altering surface vegetation cover and soil structure are the key drivers of intensified soil erosion. However, how to use existing tools and methods for the rational planning of land use resources to achieve sustainable development is the focus of current research. This study integrated the RUSLE and PLUS models to reveal the mutual feedback mechanism between land use transitions and soil erosion risks in the black soil region of Northeast China (BSNC) from 1980 to 2030. The results indicate that over the past 40 years, upland field areas have expanded by 3.04×10 4 km 2 (primarily converted from forestland and grassland, accounting for 41.2% and 38.7%, respectively), and this expansion has increased their erosion rate by 205.93 t·km -2 ·a -1 . Meanwhile, 49.22% of the newly added construction land during the urbanization process was converted from upland fields. Grassland and forestland areas have decreased by 2.15×10 4 km 2 and 1.80×10 4 km 2 , respectively. Sandy land exhibits the highest soil erosion potential risk index (7.68), with extreme sensitivity areas accounting for over 80% of its total area. Projections for 2030 establish a 20.76% and 42.17% higher regional erosion rate under the farmland protection scenario compared to the natural development and ecological conservation scenarios, respectively, resulting from the expansion of highly erodible upland field. This study establishes a regional erosion risk early warning system, thereby providing a scientific basis for optimizing territorial spatial planning and ensuring food security in the BSNC.