In addition, generation of orthophotos reduces inherent errors of photographs such
as radial distortions, etc. Since the 1970s the uses of space-borne remote sensing
techniques have increased exponentially. Techniques of image enhancement, feature
extraction, image fusion, and classification have been continuously improving, which
can be applied to detect and map degradation features. On the other hand, qualities of
remote sensing products are also improving in both spatial (80x80m of Landsat MSS to
30x30m of Land TM to 1x1 m of IKONOS) as well as spectral aspects (SPOT 3 bands,
Landsat TM 7 bands). Since hyperspectral data represent an almost continuous spectral
response, making it possible to have laboratory-like reflectance curves of earth surface
features, it is easier to characterize objects and provide wider scope for differentiating
land degradation features (Figure 1, Shrestha et al. 2003). Hyperspectral data thus
provide new possibilities for mapping land degradation.