Modeling the Impacts of Climate Change and Land Use Dynamics on Water-Induced Soil Erosion in the Qinghai–Tibet Plateau Using InVEST, CA–Markov, and CMIP6 Projections

Soil erosion (SE) caused by water is exacerbated by climate change and human activity, threatening water resources and ecological stability. The Qinghai-Tibet Plateau (QTP), with its unique ecosystem and river systems, is heavily influenced by sedimentation linked to water- induced SE. This study evaluates current SE patterns on the QTP and forecasts soil loss for 2050 and 2090 to identify priority areas for soil and water conservation. SE trends from 1985 to 2020 were conducted using the InVEST model. The CA-Markov model, in conjunction with CMIP6 climate projections, was employed to predict SE under varying land use/land cover and climate change scenarios for the future. The results found that, the average annual SE on the QTP stands at 20.02 t h⁻¹ ya⁻¹. Under the land use scenarios, SE projected to decrease by 0.2% by 2050 and by 2.24% by 2090. However, in climate change scenarios, SE is expected to rise significantly, increasing by 15.71% and 16.73% by 2050 according to the SSP2-4.5 and SSP5-8.5 pathways, respectively. By 2090, SE is expected to grow by 22.44% and 28.57% according to SSP2-4.5 and SSP5-8.5. These findings indicate that climate change, rather than LULC change, is the dominant driver of future SE on the QTP. The results provide critical insights for watershed-scale soil and water management, supporting ecological conservation strategies in this climate-sensitive region.