The Trade-Offs and Constraints of Watershed Ecosystem Services: A Case Study of the West Liao River Basin in China

Clarifying the spatiotemporal trade-offs between the supply and demand of ecosystem services is critical for regional ecological security and sustainable development. This paper focused on the West Liao River Basin, a crucial ecological barrier in Inner Mongolia, and quantified the supply and demand of ecosystem services by utilizing the InVEST model. A coupled coordination model is established to evaluate the supply–demand trade-offs, while a decoupling index model is used to analyze the dynamic changes in coordination. The influencing factors on the supply–demand relationship are also explored by using a geographically and temporally weighted regression (GTWR) model. The results from 2005 to 2020 indicated a decrease in carbon storage and an increase in carbon emissions. Water yield, food, and meat supply increased, while their demand decreased. Soil retention supply and demand both increased. Basin-scale coordination improved from low to moderate levels, with significant gains in both coordination and matching degrees. Decoupling indices fluctuated, with the central region showing a significantly higher decoupling index. The GTWR model showed that the spatial and temporal impacts of eight driving factors, including land use, on CD differed significantly, with precipitation having the most significant impact. The research results provided a theoretical basis for the future development of regional ecological restoration and sustainable development policies.