Evaluation and spatial-temporal evolution of ecosystem service value of cascade hydropower project reservoir area in the Jinsha River, China.

The Jinsha River basin, full of hydropower resources, is the largest hydropower energy base in China. From 2005 to 2018, four giant cascade hydropower stations (Wudongde, Baihetan, Xiluodu, and Xiangjiaba) were built along the Jinsha River. The reservoir area of four hydropower stations involves 26 counties (districts). The ecological environment of the reservoir area has a close relationship with hydropower projects, and ecosystem service value is an important standard to measure the quality of the ecological environment. Taking the reservoir area formed by four cascade hydropower stations in Jinsha River (Jinsha River Reservoir Area, JRRA) as the research object, the essay analyzed the spatial and temporal pattern of ecosystem service value in the reservoir area in 2005, 2010, 2015, and 2018. The results showed that (1) The ecosystem service value of JRRA reached 94 billion yuan in 2018, and the forestland took the largest proportion of ecosystem service value, accounting for 46.93%, followed by grassland, water area, cropland, and unused land. (2) From 2005 to 2018, the total ecosystem service value in JRRA increased by 3.374 billion yuan, and the spatial pattern of ecosystem service value showed a spatial distribution characteristic of high in the middle and low on both sides, and the spatial distribution had significant positive autocorrelation. (3) Because the area of water increased a lot, the ecosystem service value of JRRA showed a trend of overall increase which mainly occurred in the 3-km buffer zone along the river. The results further proved that the implementation of hydropower projects could improve the ecosystem service function in the reservoir area and provide technical support for the sustainable utilization of land resources and ecological compensation in the reservoir area.