Mapping complex patterns of erosion and stability in dry Mediterranean ecosystems

Parametrizing soil reflectance spectra with variables related to specific shape characteristics of the spectral profile permits organic carbon concentrations in soils to be estimated on the basis of regionally validated regression models. An important feature of the approach is that it can not only be applied to continuous spectra but, without notable loss in accuracy, also to the spectral resolution of operational earth observation satellites such as the Landsat-TM or -ETM systems. Using this type of imagery, it can also be shown that soil organic matter is positively correlated to growth conditions for cereal crops in dryland agriculture. Strong correlations with qualitative erosion indicators that can be derived through spectral unmixing approaches demonstrate that soil organic matter is an important indicator for assessing land degradation processes in dry ecosystems from space. (C) Elsevier Science Inc., 2000.