Tracking lakeshore wetland changes in China using Sentinel satellite data from 2019 to 2023

Study region The lakes with area larger than 100 km 2 in China Study focus A novel method integrating time-series Sentinel imagery (2019–2023) with an inundation frequency-based classification algorithm was developed to obtain the spatial distribution of lakeshore wetlands (LSWs). By applying the developed method, a spatial distribution dataset of China's LSWs with a 10-meter spatial resolution for the period of 2019–2023 was established. The spatiotemporal patterns of China's LSWs were further investigated based on the dataset and the driving mechanism of variations in LSWs under the extreme climatic conditions was discussed. The research findings were expected to support water environment management, biodiversity conservation, and watershed sustainable development. New hydrological insights Mapping results revealed that LSWs exhibit distinct spatial heterogeneity, with denser distributions in humid southeastern China. A net LSWs area loss of 2769.50 km² occurred during the study period, primarily resulting from dramatic lake shrinkage in the Eastern Plains (EP) ecoregion. Basin runoff constituted the primary controlling factor nationwide, while temperature and snowmelt exerted stronger influences in cold zones, and precipitation–evaporation dynamics dominated in arid regions. Alternating droughts and floods can lead to more frequent changes in hydrologic processes and an increase in the magnitude of water level changes in LSWs. The variations of LSWs caused by the hydrological changes would cause notable ecological effects including changes in waterbird habitat and greenhouse gas emissions.