Long-Term Ecological Environment Assessment of Qilian Mountains Based on Remote Sensing Ecological Index

Qilian Mountain is a significant ecological function area and a vital ecological security barrier in western China. However, large-scale and comprehensive studies on ecological environment quality of the whole Qilian Mountains are still very few. This study quantitatively evaluates the environmental quality using RSEI, analyzes the spatio-temporal variations of environmental quality in detail. By conducting difference change monitoring, we obtain the variation trend data of RSEI at the pixel scale. From that we get that the areas with obvious improvement were mainly distributed in the eastern region with low altitude, where the vegetation coverage rate was high, which confirmed that vegetation can improve the ecological environment quality. The stable areas account for the largest proportion, manifesting that the ecological environment quality is generally stable. The most degraded areas are mainly located in the high elevations of the Midwest. Considering the land use situation, it can be found that in these areas desertification is more serious. From the conclusions above, it’s time for people to strengthen the ecological environment protection of the Qilian Mountain, optimize the local ecological environment and protect the ecological diversity.