Desertification is one of the most serious environment problems in the world today

The generation

development and reversion of desertification are caused by the results of comprehensive influences from the climatic and environmental change

and human activities. The classification of desertification is one of the key steps in desertification research. Terrain roughness and vegetation growth are important influence factors of desertification. But it is very difficult to describe the terrain roughness in remote sensing image. In this thesis digital elevation model(DEM) was used to express the Terrain roughness of research area and normalized difference vegetation index(NDVI) were used to describe the vegetation growth. Terrain slope(SLOPE) image (produced by DEM) and NDVI image (produced by TM image) were used to fuse with original TM image. The fusion image greatly enriched the desertification information. According to n- dimension separation analysis to fusion image

the separation in templates of different kinds and degrees of desertification was increased greatly. The classification result shows that the accurate of classification was greatly improved through information fusion.