Shallow lakes in the middle and lower reaches of the Yangtze floodplain are one of the largest groups in the world.They are inherently dynamic and important sites for biogeochemical cycling, biological habitats as well as human resources.Unfortunately,most of them have undergone a substantial ecological degradation, characterized by turbid water with algae blooming, eutrophication and aquatic biodiversity loss in the past decades.This kind of widely-occurred ecological regime shift, particularly after 1950s in this region, has caused serious environmental disasters but limited knowledge existed on how the regime shift occurred in those ecosystems.