Lake-area shrinkage driven by the combined effects of climate change and human activities

Examining lake-area evolution and influencing factors is essential for understanding global environmental and societal changes and supporting ecological sustainability. Inner Mongolia, China, given its unique geographical and climatic conditions, serves as a natural laboratory for investigating the complex coupling mechanisms of “climate–hydrology–humanities.” Accordingly, we analyzed data regarding annual area changes in 655 lakes across five basins obtained from Landsat, Sentinel-2, and pushbroom multispectral scanner (1987–2023), combined with meteorological, hydrological, and human factors affecting lake-area changes. Results indicated that lake areas varied from 4059.36 to 6489.46 km² in 1987–2023, exhibiting an overall decline of 38.06 km²/a (R² = 0.39, p < 0.001). This trend was nonlinear, exhibiting area expansion (1987–1998), rapid shrinkage (1998–2010), and stabilization after a slight rebound (2010–2023). Natural factors dominated lake-area dynamics in the Songhua and Northwest River Basins, while human activities, particularly agriculture, were key drivers in the Liaohe, Haihe, and Yellow River Basins. These findings provide critical insights into the drivers of lake-area changes and establish a scientific basis for developing effective water-resource management and ecological protection strategies.