Matching ecosystem services supply and demand in China's urban agglomerations for multiple-scale management

The unprecedented urbanization rate has profoundly impacted ecosystem functions and increased the demand for ecosystem services. Moving towards sustainable cities requires an insightful understanding of ecosystem services supply and demand (ESSD). However, most ESSD studies ignore the spillover effects of ecosystem services, hindering sustainable urban agglomeration (UA) development from multiple spatial scale perspectives. This study evaluated the supply, demand, and sustainability of urban ecosystem services, including food production, water retention, soil retention, and carbon sequestration, by considering 19 UAs in China (including 236 cities). The results showed that the supply and demand of urban ecosystem services increased from 2000 to 2020, together with spatial heterogeneity. A decrease in the sustainability of food production was observed at medium UAs. Large UAs can achieve sustainability of all studied ecosystem services at both the UAs' and national scales. However, the medium UAs in the northwest were unsustainable regarding water retention and carbon sequestration at the UAs' scale. Land use/land cover (LULC) change was the key factor in ESSD change, followed by population. Finally, policy implications were proposed, including bringing ESSD into land use decision-making, reducing ecosystem service demand, implementing targeted restoration, and multiple-scale management.