Integrating Ecosystem Service Supply and Demand to Construct Regional Ecological Security Patterns

Integrating ecosystem services (ESs) into ecological security patterns (ESPs) provides a comprehensive framework for recognizing critical conservation areas and enhancing regional ecological security. However, previous studies are predominantly based on ES supply, while often not fully considering the supply–demand balance and its dynamic trends. This study proposed a comprehensive framework including comprehensive supply–demand ratio (CSDR), CSDR trend, total supply trend, and trade-off to revise ecological source recognition. Subsequently, ecological resistance surfaces were revised using land use and nighttime light data. Finally, corridors and strategic nodes were further recognized according to circuit theory to establish a comprehensive ESP. Selecting Three Gorges Reservoir Area as a research case, the results show that the ecological sources (18,232.59 km2) are predominantly situated in the eastern regions and parts of the southern bank of the Yangtze River with high supply and low ecological risks and trade-off levels. The low value of the resistance surfaces is distributed consistently with ecological sources, and the high value of the resistance surfaces is distributed near the cities with high population density and demand. Two hundred sixty-six key ecological corridors and 195 pinch points connected the regions into an organic whole and barrier points, with an area of 285.96 km2 overlapping with the potential corridors. These findings offer guidance for regional planning and sustainable development.