Abstract: Rational delineation of ecological functional areas and clarification of their driving factors are of significance for maintaining regional ecosystem stability. We assessed six ecosystem services of Sihu Lake Basin located in Jianghan Plain using InVEST and RUSLE models and recreational scoring methods. By using K-means clustering, we identified the ecosystem service bundles, and delineated the ecological functional areas in combination with ecological sensitivity and ecosystem service bundles. The dominant driving factors of different ecological functional areas were analyzed by Geodetector. The results showed that the spatial distributions of habitat quality and carbon sequestration services were similar, with high values being mainly concentrated in Changhu Lake Basin and Honghu Lake Basin. However, the spatial distributions of crop production and soil conservation services were different, with high-value areas concentrated in the northwest area with mountains. The high values of water production service were mainly concentrated in the eastern part of Honghu Lake Basin, while the high-value areas of ecological recreation service were mainly concentrated in the northwest area and the southern part of Honghu Lake Basin. The Sihu Lake Basin could be classified into crop production bundle, habitat quality bundle, and urban living bundle according to cluster analysis. The low ecological sensitivity areas accounted for 59.0% of the Sihu Lake Basin. We classified the study area into ecological restoration areas, ecological conservation areas, ecological transition areas, ecological development areas, and comprehensive use areas by combination of ecological sensitivity and ecosystem service bundles. The geodetector results indicated that the driving factors of each ecological function zone were significantly different. The natural factors significantly influenced the ecological restoration zone, while the normalized vegetation index and population density were the main influencing factors in the ecological conservation zone and the ecological development zone, respectively. Land use type was the main influencing factor in the ecological transition zone and the comprehensive use zone. The results could provide important support for coordinated regional social development and environmental protection.

Key words: ecosystem service bundle, ecological sensitivity, functional zone, Geodetector, Sihu Lake Basin