Ecological Quality Assessment and Driving Force Analysis in Wuling Mountain Area from 2001 to 2020

The ecological quality of Wuling Mountain Area (WMA) was assessed using the remote sensing-based ecological index (RSEI), integrating four indexes of greenness, wetness, heat, and dryness. This assessment relied on Google Earth Engine, a remote sensing computing cloud platform, and MODIS data. At the same time, Sen trend analysis, the spatial autocorrelation test, and the geodetector, among other spatial analytic tools, were utilized to jointly analyze the spatiotemporal changes and driving forces of ecological quality in this region from 2001 to 2020. The results show that the annual mean value of RSEI in WMA is 0.65, which is a favorable indicator of ecological quality. A pattern of "higher in the north, lower in the central-western and southeastern sections" can be seen in the spatial distribution of RSEI in WMA. Most ecological conditions are improving, and the trend toward spatial change is rising. The spatial distribution pattern has specific agglomeration characteristics, including high-high aggregation in the north, middle-east, and south and low-low aggregation in the central-western and southeast. The ecological quality of WMA has prominent vertical variation characteristics, with the increase of elevation and slope, it tends to be better and then worse and is mainly positively correlated with temperature and precipitation. The explanatory power of each natural factor on the spatial distribution of ecological quality is significantly different, among which temperature is the first dominant factor, and the interaction of both factors is greater than that of a single factor. The anthropogenic factor shows land use change and the conversion of arable land to forest land is an important reason for the overall improvement of ecological quality in WMA.