Objective Valuation of ecosystem services is critical to the sustainable development of a region and human well−being.

Methods Taking the Yangtze River Delta as the study area, we analysed the spatial and temporal distribution characteristics of four important ecosystem service functions, namely, net primary productivity (NPP) of vegetation, soil retention, habitat quality and carbon storage, in the Yangtze River Delta region from 1990 to 2020, based on the InVEST model and combining the land use types, normalised difference vegetation index (NDVI) and meteorological data. The spatial and temporal distribution characteristics of four important ecosystem services, namely vegetation net primary productivity (NPP), soil conservation, habitat quality and carbon storage, were analysed from 1990 to 2020, and hotspot areas for the four ecosystem services were identified. The correlation coefficient method was used to analyze the relationship between various ecosystem functions and land use types in the Yangtze River Delta region.

Results The results show that: ① the ecosystem service functions in the Yangtze River Delta region are spatially heterogeneous, with habitat quality, soil and water conservation and carbon storage showing a spatial pattern of "high in the southwest and low in the northeast", while the high values of habitat quality and carbon storage are distributed along the river. During the period 1990−2020, habitat quality and carbon storage services show a trend of "overall increase − local decrease", while soil conservation and vegetation net primary productivity services show a trend of "overall decrease − local increase". ② The area occupied by the three types of hotspots (hotspots, significant hotspots and very significant hotspots) in the Yangtze River Delta does not change significantly, and the distribution is obviously zonal, concentrated in the southwest. ③ In the Yangtze River Delta, there is a synergistic relationship between soil conservation, carbon storage and habitat, and NPP is a trade−off with carbon storage, habitat quality and soil conservation; among the seven land use types, NPP and soil conservation have a trade−off relationship. The trade−off/synergistic relationship between NPP and soil conservation is consistent with the Yangtze River Delta region. To ensure the sustainable management of local ecosystems, it is necessary to consider the interrelationships among ecosystem services in spatial planning to minimise trade−offs and enhance synergies.

Conclusions  This study focused on the Yangtze River Delta region and comprehensively evaluated four key ecosystem services (carbon storage, soil retention, habitat quality and net primary productivity of vegetation) in the Yangtze River Delta region through integrating multi−source datasets such as remote sensing data, geographical information data and socio−economic data, based on ArcGIS and Geoda. It systematically revealed the spatial pattern characteristics of ecosystem services in the Yangtze River Delta region on the grid−county scale, providing an important basis for in-depth understanding and optimizing the ecosystem services in this region.