Abstract: Based on the change index of ecosystem services, correlation analysis and spatial autocorrelation, this paper quantitatively analyzed the value of ecosystem services in the reservoir area from 2005 to 2018 and explored the spatio-temporal evolution of the synergy relationship of ecosystem services in the reservoir area. The results show that: (1) The ecosystem services value in the reservoir area reached to 94 billion yuan in 2018, with an increase of 4.2 billion yuan during the study period from 2005 to 2018. (2) The spatial distribution of ecosystem service value in the reservoir area is stable, showing a pattern of high in the south and low in the north, and the spatial correlation types are all positively correlated. The increasing areas of ecosystem services value are concentrated on the riparian zone of Jinsha River. (3) Supporting services of the ecosystem services value in the reservoir area has a tradeoff relationship with provisioning services, regulating services and cultural services, and the relationships between provisioning services, regulating services and cultural services are all synergistic, and the correlation of ecosystem services between the townships is mainly synergistic. The results further prove that the implementation of hydropower projects can improve the ecosystem service function of the reservoir area and provide technical support for environmental protection and sustainable utilization of land resources in the reservoir area.

Key words: Jinsha River, cascade hydropower project, reservoir area, ecosystem service, tradeoff/synergy