Hydrological Controls and Climate–Land Surface Interactions Regulating Long‐Term Lake Area Dynamics Across the Mongolian Plateau

Abstract

Lake area dynamics are sensitive indicators of hydroclimatic variability in cold‐arid regions. We reconstructed lake area changes across the Mongolian Plateau from 1990 to 2025 using Landsat imagery, JRC Global Surface Water, and HydroLAKES, and applied XGBoost and SHAP to examine associations with hydroclimatic, ecological, and human factors. Mapping accuracy was high, with overall accuracies of 96.17%–97.00% and Kappa coefficients of 0.923–0.940. Total lake area increased from 19033.31 km 2 in 1990 to 20652.31 km 2 in 2025 (+8.51%), characterized by early expansion, prolonged decline until 2009, and recovery after 2010. Mongolia accounted for most of the net increase, whereas Inner Mongolia showed weaker area growth and a decline in lake number. Climatic variables contributed most strongly to model predictions (44.36%), with potential evapotranspiration and snow cover showing greater importance than precipitation, indicating the relevance of evaporative demand and seasonal snow conditions. Regional and size‐dependent differences were also evident: Mongolia showed stronger climate‐ecology associations, whereas human‐activity variables were relatively more important in Inner Mongolia, and model performance generally increased with lake size. These results demonstrate that lake dynamics across the Mongolian Plateau reflect interacting hydroclimatic, ecological, and human influences that vary spatially and with lake size.