Abstract
Mapping and monitoring of land degradation processes such as soil erosion has become an important task for both agricultural and environmental planners. The potential of using SPOTโHRV data for assessing the types of soil erosion and land degradation is obvious. The spectral information and the spatial resolution of the multispectral data allow a high accuracy in local mapping and rapid regional assessment.
In Basilicata, southern Italy, spectral mixture modelling (endโmember techniques) has been applied to extract relevant information for assessing soil erosion. This method allows an estimate of the proportion of surface cover types (endโmembers) within the pixel. From the data sets average spectral responses were extracted for growing vegetation, nonโgreen sclerophylous vegetation mixed with dry grasses and bare soil. Using these spectra as endโmembers in the model, it was possible to decompose the spectral information of all pixels into the three surface components, giving the percentage cover of the three types within every pixel. Classification of the pixels according to the percentage of surface cover or bare soil allows an assessment of erosion or erosion risk.