黄土高原地区提取植被信息方法的研究

研究评价了适于黄土高原地区植被信息提取的最佳植被指数和方法。该地区分布有落叶阔叶林、草原和荒漠，植被类型丰富多样。然而土壤背景对植被信息提取有较大影响。经对比分析，修正后的土壤调节植被指数（ＭＳＡＶＩ）， 不仅能增强植被信号，并能大大减小土壤背景的影响，同时又能宏观地反映该地区植被类型的分布状况。它是黄土高原地区目前提取植被信息较好的植被指数。标准化差值植被指数（ＮＤＶＩ）、土壤调节植被指数（ＳＡＶＩ）和垂直植被指数（ＰＶＩ）分别适用于高密度、中等密度和稀少植被地区植被信息的提取和监测。各种植被指数多时象累加产生的图像能较好地提取植被信息

METHODS FOR COLLECTING VEGETATION INFORMATION IN LOESS PLATEAU

The optimum vegetation index and methods for collecting vegetation information in loess plateau area were studied and appraised. In this area, there were deciduous broad leaved forest, steppe and desert. Vegetation types were rich and diverse. However, collection of vegetation information was strongly influenced by the soil background .The modified soil adjusted vegetation index (MSAVI) after being compared and analysed not only could enhance vegetation signal, but also could minimize greatly the soil background effects,It could also reflect the distribution of the vegetation types macroscopically in this area. At present, it has been a more or less ideal vegetation index for collection vegetation information in loess plateau area. The collection and monitering of vegetation information for the normalized difference vegetation index (NDVI), soil adjusted vegetation index (SAVI) and perpendicular vegetation index (PVI) were used in high, medium density and rare vegetation area respectively. For a variety of vegetation indices, the images which were produced by cumulative multitemporal vegetation indices could extract vegetation information well reflecting the vegetation distribution of that particular area.