山西翼城矿区采动地表植被指数时空变化分析

Analysis on temporal and spatial variation of vegetation index in Yicheng mining influence area

以山西翼城矿区2008年釆动影响范围为对象,研究地下开采对地表植被指数NDVI变化的影响。对2008年前后8个时相的Landsat TM卫星遥感数据进行几何校正、辐射定标、大气校正及波段运算,提取工作面开采影响范围的NDVI平均值;建立各个工作面NDVI值随时间变化的曲线,研究开采前后若干年时段范围内地表植被指数的变化规律。结果表明:开采前区域植被变化主要受降雨条件影响,并与区域植被类型有关;采动过程中区域植被变化主要受采动影响,并有滞后性;采动后地表形成沉陷盆地,产生裂缝、台阶,地下水系被破坏,区域植被指数降低。

To study the influence of mining on surface vegetation index（ NDVI） change, we took Yicheng mining influence area in Shanxi in 2008 as research object. Landsat TM satellite remote sensing data of 8 time phases before and after 2008 was selected,through geometric correction,radiation,atmospheric correction and band operation,to extract the average NDVI of the mining subsidence range. A curve of NDVI value changing with time was established,to study the law of vegetation index changing within the scope of mining influence area before and after mining. The results show that,before mining,regional vegetation change is mainly influenced by rainfall conditions,and related to the regional vegetation types; during mining it is mainly affected by mining,and the influence is lagged; after mining,subsidence basin,cracks,steps are formed on the ground,and underground water system is damaged,leading to a decline of the vegetation index.