Spatial Association and Trade-off/Synergy Relationships between Ecosystem Health and Human Well-being: A Case Study of the Manas River Basin

Identifying the linkage between ecosystem health (EH) and human well-being (HWB) is crucial for understanding natural–social system interactions. However, research on the spatial associations and conflict/cobenefit relationships between EH and HWB remains limited. Using the Manas River Basin as a case study, we quantitatively assessed EH and HWB from 2000 to 2020. By integrating Lee’s L statistic and Spearman’s rank correlation, we revealed their spatial correlation and trade-off/synergy mechanisms between EH and HWB. Results show that (1) EH exhibited a slight increase (0.14 → 0.166), with a “high–medium–high–low” spatial pattern from south to north. High values were concentrated in upstream forests and midstream agricultural oases, while low values occurred in piedmont grasslands and downstream deserts, closely linked to oasis agricultural development. (2) HWB increased significantly (0.106→0.738), shifting from economic well-being (EcoWB) and educational/cultural well-being (ECWB) dominance to diversified development encompassing health and safety well-being (HSWB), environmental well-being (EnvWB), and EcoWB. Its spatial evolution followed an urbanization-driven “agglomeration → diffusion → rebalancing” pattern centered on oasis towns. (3) EH and HWB showed significant spatial dependence, but their correlation weakened over time, indicating spatial decoupling of human activities from natural systems. High EH–high HWB clusters were predominantly in midstream oases, whereas high EH–low HWB clusters were located in southern forests. (4) Trade-offs and synergies varied along the landscape gradient: ecological stress traded off with all HWB types, while ecological function showed stable synergies with EnvWB and increasing synergies with EcoWB and ECWB. These findings provide insights into EH–HWB coevolution and support sustainable development in arid-region basins.