Abstract:

The Horqin Sandy Land suffers from severe land desertification. Research into the spatiotemporal evolution patterns of the wind erosion prevention and sand fixation service holds significant importance for regional ecological security and sustainable development. This study systematically analyzed the spatiotemporal dynamics， driving mechanisms of wind erosion prevention and sand fixation service in the Horqin Sandy Land from 2000 to 2020 using the Revised Wind Erosion Equation （RWEQ） model， the XGBoost-SHAP algorithm， and HYSPLIT trajectory simulations. The results indicate： （1） The wind erosion prevention and sand fixation service exhibited significant spatiotemporal heterogeneity. The sand fixation per unit area showed a trend of initial decrease followed by increase， with a spatial pattern characterized by a higher in the central-southern regions and lower in the northern areas. （2） The XGBoost-SHAP model quantified vegetation coverage as the core driving factor， while interactions among wind days， precipitation， and temperature nonlinearly influenced wind erosion processes. （3） HYSPLIT simulations identified 3 559 sand transport trajectories over the 20-year period， with an overall decline in trajectory frequency， indicating enhanced sand fixation capacity. Cluster analysis revealed four dominant pathways： 31.67% of trajectories moved eastward into the Pacific Ocean， 29.92% influenced northeastern regions （Jilin and Heilongjiang）， 20.46% crossed borders to areas such as North Korea and Japan， and 17.95% migrated southward to China’s southeastern coast. These findings provide a scientific basis for optimizing desertification control strategies and coordinating regional ecological compensation mechanisms， while offering methodological references for studying ecosystem service flows in arid and semi-arid regions.

Key words: wind erosion prevention and sand fixation service, HYSPLIT model, XGBoost-SHAP model, Horqin Sandy Land