Based on Landsat TM satellite remote sensing image data, the paper utilized the vegetation index and vegetation fraction to analyze their spatio-temporal evolution and its driving factors. Spatial heterogeneity and its driving mechanism of vegetation fraction were analyzed under the linkage of mining and reclamation. Based on regression coefficient, standard deviation, gradation conversion matrix, and so on, we revealed the response of the vegetation cover to the mining and reclamation activities with time through the analyses of the trend and fluctuation of vegetation coverage in the study area, the mining area and the reclamation area. The results showed that the vegetation fraction and its grade in different years had some similarity, and the pattern of spatio-temporal evolution was broken by mining and reclamation activities in open pit mines to some extent. The vegetation coverage in the study area was mainly the middle (Grade IV) and the middle-low (Grade III) level, and according to the average of many years, both of them accounted for more than 80% of the total area of the study area. The ratio of the area with increased vegetation cover degree to the area with decreased vegetation cover degree was 2:3, and correlation coefficient was between -0.9266 and 0.4805. The correlation was not significant in the range of positive value, but was significant in the negative part. Correlation coefficient from -0.9266 to -0.895 was through the significance test of 0.025, and vegetation damage was the most severe, which belonged to a very significant change, and almost all were distributed in the exploited Xi’er, Xiyi and Dong’er open-pit stope and their solid waste yard, industrial sites and road with an area of about 4.85 km2. The standard deviation (SD) of inter-annual vegetation fraction for the study area was in 0-0.49. The vegetation fraction of open pit area, dump and surrounding areas with a range of 1.5 km was significantly decreased, and had gradually converged. Reclamation revegetation would experience a “high-low-high” cycle in the study area, and according to the changes of vegetation reclamation, protection period must ensure more than 6 years in semiarid grassland. In the study area, the land reclamation standard was higher than the surrounding area, and the recovery effect was better. More than 70% of areas had the transition of vegetation fraction, and the transition was relatively frequent. The fluctuation degree for the area of Grade III and II was the largest, which were the most damaged. There was 90 percent of the area of GradeⅠwhich was transferred by the mining activities. To enhance the vegetation coverage in the study area, it was required to reduce the social pressure and improve the ecological resilience. To reduce social pressure, we should consider the coal mining and solid waste stacking technology, with minimal impact on the ecological process in the form of a layered, limited mining area and stope arrangement for solid waste. The improvement of ecological resilience should increase the input of land reclamation, and steadily improve the coefficient of vegetation restoration in the mining area. The research results will provide information support for the ecological environmental protection and decision making, restoration and management in the area of open pit coal mine.%采用多时相Landsat TM遥感数据，借助于植被指数与植被覆盖度，基于不同时序植被覆盖度格点回归斜率、标准差和基末年等级转换矩阵等，分析了研究区植被覆盖度空间异质性及其驱动机制，剖析了采复联动下研究区、开采区和复垦区植被覆盖度变化趋势和波动程度，进而揭示随着时间变化采复活动与植被覆盖度间的响应。研究结果表明：不同年份研究区植被覆盖度及其等级空间分布整体上具有一定相似性，矿山采复活动在一定程度上打破了区域植被覆盖度时空演变格局；研究区植被覆盖度以中（Ⅳ等）、中低（Ⅲ等）为主，按多年均值计算，两者之和占研究区总面积的80%以上；植被覆被度呈增加和减少的区域面积比为2∶3，相关系数在−0.9266～0.4805之间，斜率正值范围内相关性并不显著，而负值范围的−0.9266～−0.895呈现不同程度显著性相关；露天采区、排土场及其周边1.5 km范围内的植被覆盖度呈显著下降趋势，且趋于一致。矿区植被恢复经历了一个“高—低—高”的周期循环，半干旱草原区复垦管护期限尽量保证在6 a以上。70%以上区域在研究时段内植被覆盖度发生转换，转换较为频繁，Ⅰ等植被覆盖度中的90%是由采矿活动转入的。露天煤矿区植被覆盖的提升有赖于矿区社会压力减少和生态恢复力提高两方面。研究成果将为露天煤矿及其所在区域生态环境科学保护与决策、恢复和治理提供信息支撑。
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