Abstract: study of interspecific association and combined population patterns of Stipa bungeana steppe community is carried out by means of x²-test, variance ratio methOd and Kershaw's covariance analysis. The results show:(1) among45 species pairs in10 species,6 pairs are positively associated,5 pairs are negatively associated,and the rest 34 pairs are not associated;(2)according to the above results,10 species could be divided into three groups:the association being negative among groups and highly positive with each group;(3)the com-petition fOr living space and resources among Stipa bungeana,Artemisia frigida,Carex rigetcen is the basis for the formation of interspecific relation in the community,and the separation of the 3 species constitutes the basis of the spatial patterns of the whole community.

Key words: apple tree, canopy reflectance retrieval, terrain radiometric correction, mix-pixelanalysis, 6S Model.