Study on ecological quality evaluation of mining area based on remote sensing green index—Taking Yima mining area as an example

Mining and development of mining area poses significant impact on regional ecological quality. This study proposed a new remote sensing green index(RSGI)model more tailored for evaluating the ecological quality in the mining area by taking the Yima mining area as an example for analysis. The model was first applied to the ecological quality evaluation of the Yima mining area. Based on Landsat remote sensing images in 1991, 2011 and 2021, ENVI5.3 software was used to supervise the classification of remote sensing images and calculate the green index of remote sensing. The ecological quality of Yima Mining area in the past 30 years was evaluated from the perspective of time and space. Pearson correlation coefficient is used to analyze the correlation between ecological quality and ecological factors in mining area. Results showed that: ① From 1991 to 2021, the overall ecological quality was satisfactory, with the green space area reached more than 80 %. ② In 1991, 2011 and 2021, the RSGI values of Yima mining area were 0.90, 0.91 and 0.89, respectively. The ecological quality of Yima mining area showed initial increase and then a slow decline, and the overall ecological quality exhibits in a downward trend. ③ From 1991 to 2021, there were significant changes of eco-quality in towns and mining areas, with a downward trend observed in most regions. This indicates that the changes of eco-quality in Yima mining area is closely related to mining activities. ④ Areas with high remote sensing green index demonstrate larger proportion of cultivated land, forest land and grassland, and smaller proportion of buildings and impervious surface area. There is a significant correlation between remote sensing green index and other indexes. The research results provide reference for eco-environmental restoration and green mine construction in Yima mining area.