Abstract:
The development of mineral resources has promoted economic and social development, but at the same time, it has a significant impact on the ecological environment. Since the 18th National Congress of the Communist Party of China, China has implemented a series of ecological protection projects to strengthen the ecological restoration and governance of mines. Vegetation is a natural “link” connecting land cover elements such as soil, atmosphere, and water. Qualitative and quantitative analysis of the ecological evolution characteristics and influencing factors of vegetation in mining areas can timely grasp the development status of vegetation restoration in mining areas, which is of great significance for the ecological restoration and effective management of typical mining areas. This paper is based on multi-scale satellite images, land-cover data, temperature and precipitation data, and uses the dimidiate pixel model to retrieve fractional vegetation coverage, trend analysis, correlation analysis, etc., to analyze the temporal changes in vegetation coverage before and after ecological restoration in the Qilian Mountains National Nature Reserve and mining areas within the reserve, and to explore the influencing factors of vegetation coverage changes. The research results show that in the past decade, the vegetation coverage of protected areas has shown an overall fluctuating trend, and different spatial patterns were observed before and after 2017. Before 2017, vegetation coverage in the northwest showed an improvement trend due to precipitation, while vegetation coverage in the central and southeastern regions showed a degradation trend due to human activities such as mining development and overgrazing. After 2017, the vegetation coverage in the central and northwestern parts of the protected area showed a degradation trend due to the impact of warm and dry climate after 2020, while the vegetation coverage in the southeastern part showed an improvement trend due to ecological restoration and management. The vegetation coverage in the mining areas within the protected area has significantly improved after 2017 due to ecological restoration, with an overall increase of 27.3% in vegetation coverage and an improvement area of 55.92%. Among them, the vegetation coverage in the mining areas within the Wuwei section has improved significantly compared to other areas. Research has found that the areas with significant changes in vegetation coverage within the protected area are basically consistent in spatial distribution with areas with high correlation between vegetation coverage and precipitation and temperature, indicating that vegetation coverage changes are more influenced by climate factors on a large scale. The vegetation coverage in mining areas continued to deteriorate before 2017, but showed a significant improvement trend after 2017, indicating the impact of human activities on changes in local vegetation coverage.