[Spatiotemporal Matching Measurement and Coupling Coordination Analysis Between Ecosystem Service Supply-demand and...

As a critical ecological barrier in the upper reaches of the Two Rivers, Southwest China exhibits high habitat heterogeneity and significant urban-rural disparities. Investigating the coupling coordination relationship between ecosystem service supply-demand balance and human well-being is of great significance for regional sustainable development. Taking prefecture-level cities in the southwestern region as study units, this research measured the supply-demand relationships of five key ecosystem services: grain yield, carbon sequestration, water yield, soil conservation, and habitat quality. Combined with human well-being indicators, the study employed coupling coordination models and spatial autocorrelation analysis to reveal the spatiotemporal coupling patterns and spatial association characteristics of ecosystem service supply-demand and human well-being from 2000 to 2022. The results indicate: ① During the study period, the supply of grain yield and carbon sequestration increased, while water yield, soil conservation, and habitat quality supply declined. Demand for carbon sequestration, water yield, and habitat quality grew, whereas grain yield and soil conservation demand decreased. The supply-demand ratios of grain yield and soil conservation rose, while those of carbon sequestration, water yield, and habitat quality declined. Overall, ecosystem services maintained an ecological surplus (supply > demand) with significant spatial heterogeneity, with the Chengdu-Chongqing urban agglomeration and other high-intensity human activity areas showing a "low supply-high demand" deficit pattern, while western Sichuan and the Yunnan-Guizhou plateau maintained surplus conditions. ② The average human well-being index across southwestern prefectures at six temporal nodes was 0.207, 0.219, 0.248, 0.304, 0.356, and 0.371 respectively, demonstrating continuous improvement. ③ The coupling coordination degree between ecosystem service supply-demand and human well-being increased from 0.520 to 0.772, indicating significant improvement in their synergistic relationship and a shift toward more sustainable socio-economic and natural environment interactions. ④ During the study period, the global Moran's I values of the coupling coordination degree at the six time nodes were 0.486, 0.504, 0.438, 0.402, 0.414, and 0.306, respectively. The coupling coordination degree exhibited a significant positive spatial correlation, though both the spatial dependence and clustering characteristics showed a weakening trend. This indicates a gradual reduction in spatial heterogeneity and an evolution of the regional development pattern toward greater equilibrium. The research findings can provide a scientific basis for optimizing ecological conservation redlines, establishing differentiated ecological compensation mechanisms in Southwest China, and promoting harmonious coexistence between humans and nature.