【摘要】 本文探讨了应用多时相Landsat Mss图像进行森林动态监测的方法。研究了差值图像法、比值植被指数差值法、归一化植被指数差值法、多时相主分量分析法(垂直植被指数法)和分类比较法对提取森林动态变化信息的作用。结果表明,3种植被指数法都能较好地提取植被动态信息,可用于森林面积消长的动态监测。更多还原

【Abstract】 The paper deals with the method of detection of forest change using Landsat MSS data of May, 1976 and October 1985 from frame of Pingchuan County, Hebei Province. The false color composites. (Band 7, 5, 4) were produced. The false color image is useful for manual interpretation of forest Change dynamics. A normalized difference vegetation index (NDVI) and a ratio vegetation index (RVI) were computed for two dates of Landsat data. The difference images for NDVI and RVI were produced by subtracting 1976 from 1985 data. the difference images indicate the great forest change between the above two data. Various standard deviation threshold levels were applied to the difference images to find the threshold value to produce the highest change classification accuracy. Principal components analysis of eight-channel data set consisting of the two landsat MSS data parity to generate the principal components. The first component is related to forest changes. The data classification techiques can monitor the changes of landcovers.更多还原