基于遥感数据的岷江上游水域动态监测——以汶川县为例

Dynamically monitoring of minjiang area based on RS data—a case of Wenchuan County

以1994年的Landsat TM影像和2002年的Landsat ETM+影像为数据源,分别采用多波段谱间关系法和阈值法相结合,以及水体指数法(MNDWI)和阈值法相结合对汶川县内的岷江干流信息进行识别,结果表明使用多波段谱间关系法和阈值法的结合效果更好,并对比分析了以此方法提取出的水体信息,对近10年的岷江水体面积变化进行动态监测,结果显示汶川县内岷江干流水域面积减少了0.8%。

Based on the sources of Landsat TM in 1994 and Landsat ETM＋ in 2002 , the water body information of Minjiang in Wenchuan county is identified by using the multispectral relationship and threshold method and the modified normalized difference water index and threshold method. The results show that the multispectral relationship and threshold method is better. According to the water information extracted with this method, the water area in the past ten years are analyzed, which decrease 0.8 % from the result.