Regional Spatial Management Based on Supply–Demand Risk of Ecosystem Services—A Case Study of the Fenghe River Watershed

The supply–demand risk assessment of ecosystem services (ES) can identify the supply–demand risk level, which is very important for the sustainable management of regional ES. In this study, taking the Fenghe River watershed (FRW) as a case, based on the status and the change trend of the supply–demand ratio of ES, and the ES supply change trend, the supply–demand risk level of food provision (FP), water yield (WY), soil retention (SR), and climate regulation (CR) are evaluated, and the risk management zones of the FRW are divided using spatial superposition. The results show that: (1) The supply and demand of SR are spatially matched, while the other three ES are spatially mismatched. (2) From 2000 to 2015, the supply amount of FP, WY, and SR increases by 11.59%, 1.25% and 55%, respectively, while the supply amount of CR decreases by 5.15%. At the same time, the demand amount of FP, WY, SR and CR increases by 39.97%, 53.88%, 36.3% and 215.5%, respectively. (3) The supply–demand ratio means of four ES in the FRW are all greater than 0, but there are some areas within that are less than 0. (4) In terms of sub-watershed scale, except for SR, there are critically endangered areas for the other three ES. Moreover, the FRW is divided into 11 supply–demand risk management zones, such as FS-WY-CR critically endangered zone, WY-CR critically endangered and FS vulnerable zone. The supply–demand risk management zones based on multiple ES can identify the risk level of each ES in each zone. These results and conclusions can provide the basis for rational allocation of resources and sustainable management of ES.