Ecological environment quality analysis of Jiyuan City based on improved remote sensing ecological index

With the high-speed development of Jiyuan City, frequent human activities have caused increasing impacts on the ecological environment, so remote sensing monitoring of the ecological environment is of great significance for assessing the sustainability of regional ecosystems and human living environment. In this study, based on the Remote Sensing Ecological Index (RSEI), the Improved Remote Sensing Ecological Index (IRSEI) was created by choosing the Index of Building (IBI) and the Index of Bare Soil (SI) to represent the dryness indicators, respectively, and combined with the Principal Component Analysis (PCA) method to evaluate and analyse the quality of the ecological environment in Jiyuan City from 2002 to 2021. Conclusions were drawn: ① From 2002–2021, the five-year improved remote sensing eco-indexes of Jiyuan City were 0.50, 0.57, 0.59, 0.64, 0.62, respectively, with an overall increase in the ecological environment quality; ② During the study years, the area of grassland and water bodies in Jiyuan City increased continuously, with a total increase of 254.131 km2, and the area of bare soil and planted cultivated land decreased gradually, with a total decrease of 211.211 km2; ③ In terms of spatial distribution, the ecological environment quality in the northwestern mountainous area is the best, and the eastern urban area is relatively poor. Overall, the ecological environment management in the study area has achieved some success, but there is still much room for improvement.