<正>在对原始ASTER9个波段进行图像融合和特征变换的基础上，结合江苏建湖县8种主要地物类型的训练区数据，以及48个杨树样地的测树因子数据，从分类性能和生物物理参数建模的相关性角度对多种图像融合方法和特征变换方法进行了客观评价。结果表明：植被指数变换生成的植被指数组合在8类地物的平均可分性上性能较优，HIS融合生成的H波段对于估算杨树单位面积蓄积量和杨树平均高效果较好，NDVI适宜反演杨树年龄。

Using Levins and Shannon-Wiener niche breadth index, the niche of Betula luminifera population and its main associated tree species in Fuyuan County, Yunnan was studied. The results showed that B. luminifera had the biggest niche breadth. The niche breadth of Cunninghamia lanceolata, Pinus armandi ranks second. The niche breadth of other associated tree species was smallest. It indicates that B. luminifera has extensive adaptation to environment and it is the dominant species in the community. The niche proportional similarity between B. lumini f era and C. lanceolata, P. armandi was larger, showing that B. lumini f-era and C. lanceolata, P. armandi had greater resource-sharing degree. But the niche proportional similarity between B. lurninifera and most of other associated tree species were small. The niche overlap between most of tree species in B. lurninifera community were smaller, which indicated a higher niche polarization of main tree species and a weaker competition in B. lumini fera community.