Abstract: Dianchi Lake is the largest high-altitude freshwater lake in southwest China and the largest freshwater lake in Yunnan Province. Understanding the spatiotemporal variations of land use/cover types and habitat quality in the Dianchi Lake basin is of great significance for the protection of the ecological environment in the basin. Based on land use/cover data from 1988 to 2018, we analyzed the spatiotemporal variations in habitat in the Dianchi Lake basin using InVEST model and the spatial analysis tool of GIS, and quantified the spatial aggregation and evolution characteristics of habitat quality using Moran’s I index and hot spot analysis. The results showed that: (1) Land use/cover types in the Dianchi Lake basin changed dramatically, from the dominance of farmland in 1988 to the dominance of urban land in 2018. (2) The overall habitat quality in the basin declined, with lower habitat quality in the urban areas surrounding Dianchi Lake and higher quality in the surrounding mountains and hills, but distributed sparsely. (3) The cold and hot spots of habitat followed aggregated distribution. Hot spots were mainly located in the surrounding forests, and their range gradually shrunk with time. The cold spots were located in the urban areas surrounding Dianchi Lake, and their number increased greatly over time. Our results indicate that the drastic change of land use/cover during urbanization is a main reason for the changes of urban habitat, providing reference for optimizing land use types and improving or maintaining biodiversity in Dianchi Lake Basin.

Key words: habitat quality, land use/cover change, InVEST model, Dianchi Lake basin