Variations of Ecosystem Services Supply and Demand on the Southeast Hilly Area of China: Implications for Ecosystem Protection and Restoration Management

The balance between the supply and demand of ecosystem services (ESs) is an important prerequisite for maintaining the sustainability of ecological protection and restoration project implementation. However, research related to ecological protection and restoration is insufficient for the study of the demand for ecosystem services. Many ecological protection and restoration projects have been implemented in the Fujian Province, but the ESs and the relationship changes between supply and demand are not clear. In this study, multisource remote sensing and public data and the InVEST model were used to quantitatively assess and map four typical ESs, including food production, water yield, soil retention and carbon sequestration. Hotspot analysis was used to analyze the spatial cluster of the ESs supply-demand ratio. The results showed that: (1) there were trade-offs between supporting and regulating services, particularly between carbon sequestration and water yield services, and the strength of trade-offs or synergies between food production and other services was stronger in protection and restoration areas than in other areas; (2) the supply of ESs in the Fujian Province exceeded the demand, and the supply-demand ratio for ESs decreased from the mountainous regions in the northwest interior to the economically developed regions in the southeast coast; and (3) ecological restoration projects improved the relationship between supply and demand for some ESs, while other areas (except protection and restoration areas) had many low-value clusters of supply-demand ratios, especially regarding water yield and carbon sequestration services. Based on the results, our findings also provide suggestions for ensuring the sustainability of ecological protection and restoration in southeast hilly areas and other similar regions.