Dataset for obtaining phytoplankton composition in freshwater lakes

In this study, Landsat satellite images (1986–2024) were used to reconstruct the spatiotemporal distribution of three major phytoplankton communities (Cyanophyta, Chlorophyta, and Bacillariophyta) in freshwater lakes across China using a method combined machine learning and absorption decomposition. Over the past four decades, the relative proportion of Cyanophyta in Chinese freshwater lakes as declined significantly, with a decrease of 1.94% decade-1, whereas sustained increases were observed for Chlorophyta (+2.85% decade-1) and Bacillariophyta (+2.92% decade-1). Notably, a significant rise in phytoplankton diversity was detected in 62.8% of lakes, while only 2.80% exhibited a decline trend, and the remaining lakes showed no significant trend.