COST-EFFECTIVE PASTURE RESOURCES ESTIMATION FROM SPACE

摘要

In an effort to develop a cost-effective method to quickly estimate the amount of pasture resources in a nomadic Mongolian steppe, we have conducted detailed aboveground biomass measurements that coincide with the high-resolution multispectral satellite image data. In much part of Mongolia, where no fixed grazing land is enforced, the quantitative evaluation of available pasture resources at a given locality has been difficult to achieve. We captured a high-resolution satellite image data using 2.4-meter resolution QuickBird over the test site with varying biomass amount. A close correlation between the aboveground biomass and vegetation index computed from the multispectral image data was evident, which supported other previous efforts (correlation coefficient of up to 0.79). When several dominant vegetation communities were pre-delineated for vegetation index to be weighted, the resulting aboveground biomass estimation was improved. Delineation of these vegetation communities was made possible using the panchromatic counterpart of the high-resolution image data (0.6-meter QuickBird). Although, the use of high-resolution image data over a large area is economically prohibitive, the hierarchical procedure to estimate the amount of pasture resources developed in this study forms the basis for practical application of reasonably priced medium-resolution satellite data at a regional scale.