Ecological Environment Evaluation and Driving Force Analysis of Qujing Based on an Improved Remote Sensing Ecological Index Model

This study uses Landsat TM/OLI remote sensing images from 2000, 2005, 2010, 2015, and 2020 to construct an improved karst remote sensing ecological index. The temporal and spatial changes in the quality of the ecological environment in Qujing City from 2000 to 2020 were analyzed using Sen's slope estimator and the Mann–Kendall trend test. The optimal parameter geographic detector model was further used to optimize the zoning effect of spatial data and quantify the impact of different factors on the spatial heterogeneity of ecological environment quality. The results show that from 2000 to 2020, the overall quality of the ecological environment in Qujing City has improved, with significant spatial heterogeneity. In terms of space, it presents a distribution pattern of "low in the northwest and high in the southeast", and the area of "excellent" and "good" levels has gradually increased. According to the trend analysis using the Sen slope and MK tests, the area with improved ecological environment quality accounts for more than 60%, although some areas still show degradation. The results of the optimal parameter geodetector model show that ecological environment quality is influenced by multiple factors, among which NPP, land use type, DEM, and temperature have significant effects, and the interactions among these driving factors further amplify their impact on ecological quality. These findings provide a methodological reference for the remote-sensing evaluation of ecological environment quality in karst areas and offer insights that promote ecological environment protection and the sustainable development of the regional social and economic in karst areas.