Abstract: Lakes are important land resources, and the study of the dynamic changes of lake waters is conducive to providing an important guarantee for the development and utilization of regional water resources and the stability of ecological balance. Based on Google Earth Engine, using multi-source remote sensing data from 1989 to 2022 as the data source, in normalized difference water index (NDWI), modified normalized difference water index (MNDWI), automatic water extraction index (AWEI_sh) and the water index (WI₂₀₁₅) selects the optimal water body index from the four commonly used water body indexes to extract the water body of Dongting Lake Basin. Combined with various data such as precipitation, temperature, population density and land use in the basin to explore the Dongting Lake analysis of water body evolution characteristics and driving forces in the lake basin. The results show that, from 1989 to 2022, the water body area in the Dongting lake area showed an overall downward trend in the wet and dry seasons, and the three major lake areas all had different degrees of reduction, with an average reduction of 93.27 km²and 140.15 km². The area of lakes in the basin is the result of the combined effects of natural climate change and human activities. Precipitation and temperature are important natural factors affecting the area of lakes. The increase in population and the transfer of land use types caused by reclamation of lakes are the human factors for the reduction of lake area.

Key words: multi-source remote sensing data, Google Earth Engine, Dongting Lake, spatio-temporal evolution