利用植被指数(Ⅵ)提取遥感影像荒漠林覆盖度信息的差异性研究

Study on the Differences among 3 Kinds of Vegetation Indexes (Ⅵ) in Extracting Coverage of Desert Forest with Remote Sensing Image

本研究针对荒漠林在遥感影像中的表现特征,选用归一化植被指数(NDVI)、重归一化植被指数(RDVI)和土壤调节植被指数(SAVI),比较分析通过遥感影像灰度图的判读和植被指数分析荒漠林的覆盖度。结果表明:3种植被指数在探测干旱区稀疏植被覆盖度的能力方面存在差异。RDVI探测稀疏植被覆盖度的能力明显劣于NDVI和SAVI。NDVI和SAVI表现基本一致;由于土壤因素的影响,在估测稀疏植被覆盖度方面,NDVI的能力较SAVI强。

In accordance with the characteristics of desert forest in remote sensing images,this paper employs Normalized Difference Vegetation Index（NDVI）,Renormalized Difference Vegetation Index（RDVI） and Soil-adjusted Vegetation Index（SAVI） to conduct a comparative study on the coverage of desert forest via analyses of gray images and vegetation indexes.The result suggested that these 3 vegetation indexes differ in their ability to detect low coverage vegetation in arid areas.There is no distinct difference between NDVI and SAVI in its ability to detect coverage vegetation in arid areas, whereas RDVI is obviously inferior to NDVI and SAVI.However,NDVI is far superior to SAVI when considering the influences of soil background.