基于HJ-1影像与地形因子的竹资源专题信息提取研究

Thematic Information Extraction of Bamboo Resources Based on HJ-1 Remote Sensing Image and Terrain Factors

以永安市的DEM数据和HJ-1多光谱影像为数据源,研究不同坡度、坡向、海拔等地形条件下竹资源的光谱反射率曲线及辅助于地形因子的竹资源专题信息提取效果。结果表明,海拔、坡向对竹资源的光谱反射率影响大,而坡度影响小,在海拔400m^800m和800m^1200m范围内阳坡、半阳坡、阴坡、半阴坡的竹资源的光谱反射率差异最为明显。采用最大似然法结合地形因子辅助分类提取的竹资源专题信息精度为74.50%,比单纯依靠光谱信息分类的精度高14个百分点,说明地形因子对竹资源专题信息提取具有很大帮助,可以辅助解决"同物异谱"和"异物同谱"问题。

The effect of the bamboo thematic information extraction assisted by the terrain factors and the spectral reflectance curve of bamboo resources in different terrain conditions (slope,aspect,elevation)were analyzed with the DEM data and RS data in Yong’an City.The results show that the most impact terrain factors on the spectral reflectance curve of bamboo resources are altitude and aspect,the less impact factors is slope.There are obvious differences on the spectral reflectance curve of bamboo resources between the altitude of 400m^800m and 800m^1200m under the sunny aspect,semi-sunny aspect,shady aspect and semi-shady aspect.The accuracy of bamboo thematic information extraction by the maximum likelihood method with the help of the terrain factors is 74.50% which is 14 point higher than the classification based on spectral information only.It shows that the terrain factors could be great help for the bamboo thematic information extraction and could solve problems in the images about “the same object with different spectrums”and “the same spectrum for different objects”.