Abstract: [Purposes]Addressing the problems of insufficient long-term dynamic monitoring of lakes in the Yellow River basin,unclear area-size structure,and poorly understood seasonal fluctuation mechanisms,this study utilized Google Earth Engine and Landsat imagery from 1986 to 2024 to systematically extract lake water bodies using an improved DSWE algorithm.[Methods]The reliability of the method was confirmed through accuracy assessment (overall accuracy 96.95%,Kappa coefficient 0.94).We systematically analyzed the interannual changes,spatial distribution,size-class structure,and seasonal fluctuations in lake number and area,and employed the Mann-Kendall trend test to evaluate change trends,thereby revealing the spatiotemporal evolution patterns of lakes over the past 40 years.[Findings]The results indicate that:①The number of lakes in the basin increased by an average of 46.64 per year,with a significant expansion in total area (Z=7.45,P<0.001),primarily contributed by the upstream region; ②The lake structure exhibits a “scissor-shaped”pattern where a few large lakes (≥50 km²),comprising only 0.12%of the total number,dominate the area (contributing 51.40%),while the vast majority are small lakes;③Small lakes (<1 km²)show significant seasonal fluctuations,whereas large lakes remain relatively stable.[Conclusions]This research provides a scientific basis for water resource management and ecological protection in the Yellow River basin.

Key words: Yellow River basin, DSWE, Google Earth Engine, water resource management