Surface water changes in China's Yangtze River Delta over the past forty years

Surface water security is a challenge in highly urbanized, economically active, and high water consumption regions. Exploring the supply and demand of surface water resources in developed is conducive to promoting the sustainable socioeconomic development of these agglomerations. The Yangtze River Delta (YRD) region is one of the most important world-class urban in China. However, it is unclear how surface water has responded to underlying impacts of climate change and anthropogenic water exploitation over the past decades. Here, we monitored the spatiotemporal characteristics of surface water and investigated the driving forces and regional impact of surface water changes. We found that (1) the trend in surface water body area in China's YRD was stable over the past 40 years; (2) precipitation and the digital elevation model best determined the spatial dis-tribution of surface water in the YRD; (3) the construction of reservoirs was the main factor for the increase of surface water area; and (4) the increase in population density was the main driver of the decrease in surface water area. Human activities deplete and artificially increase surface water supply, which tends to offset; human activities have decreased water conservation services and soil and water conservation services of the YRD.

Automated summary

Surface water security is a challenge in highly urbanized, economically active, and high water consumption regions. Exploring the supply and demand of surface water resources in developed is conducive to promoting the sustainable socioeconomic development of these agglomerations. The Yangtze River Delta (YRD) region is one of the most important world-class urban in China. However, it is unclear how surface water has responded to underlying impacts of climate change and anthropogenic water exploitation over the past decades.