The contribution of biodiversity to human well-being is key to exploring the relationships between biodiversity, ecosystem services (ES), and human well-being. In this work, a composite index, termed the human well-being index (HWI), was constructed for evaluating the contribution of biodiversity to human well-being in the Sanjiangyuan area. This index consists of material, ecological regulation, and spiritual and cultural contributions, represented by the material index (MI), the ecological regulation index (ERI), and the spiritual and cultural index (SCI), respectively. The system was further used to evaluate the spatiotemporal distribution of human well-being at the county level in 2000, 2010, and 2020. HWI increased steadily across Sanjiangyuan over the study period, especially in the western and northeastern counties; its center of gravity shifted in the northward direction. The MI increased (decreased) in the west and northeast (southeast); its center of gravity shifted in the northeast direction. All counties showing changes in the ERI were located in the eastern part of Sanjiangyuan. The center of gravity of ERI did not change significantly. The SCI increased steadily across the study area, but was high in the west and low in the east; the center of gravity shifted in the northwest direction. The study findings can contribute toward quantifying biodiversity contributions to human well-being and the formulation of biodiversity conservation policies.

Exploring the driving factors of changing ecosystem services is critical for supply capacity maintaining and ecological management zoning. Xinjiang of Northwest China, is considered one of the most fragile ecological environment areas. However, studies on how ecosystem services’ driving forces respond to the environmental conditions of Xinjiang are still insufficient, especially in sub–regions with considerable spatial heterogeneity. Based on 106 counties across Xinjiang, we employed models of the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and Revised Wind Erosion Equation (RWEQ) to quantify four essential ecosystem services (carbon storage, habitat quality, and sand fixation and water yield). Then, we investigated the spatial distribution of four ecosystem services and drivers at the county scale in 2020 by using multi–scale geographically weighted regression (MGWR). The results showed that the spatial distribution of ecosystem services is higher in the north and lower in the south, and hotspots and high–value ecosystem services areas were consistent. Precipitation, temperature, and fractional vegetation cover were the dominant factors influencing the four ecosystem services. Therefore, regulating climate and increasing vegetation will maximize the improvement of regional ecosystem services in Xinjiang. Significant differences exist in the counties of the type, intensity, and direction of ecosystem services drivers. The correlation between carbon storage, habitat quality and fractional vegetation cover was more robust stronger in the south. Water yield was more closely related to fractional vegetation cover in southern Xinjiang. Under different ecological and social conditions, the impact of driving forces on ecosystem services showed different changing trends. Three suggestions for improving ecosystem services management were proposed based on our results. The comparative analysis of the driving factors of county ecosystem services in this study will help to formulate differentiated ecological protection policies and promote a sustainable supply of ecosystem services in Xinjiang. In the future, it is necessary to strengthen the long-term monitoring and evaluation of ecosystem services and the research on the interaction of multiple drivers.