Indicators for the estimation of vulnerability to land degradation derived from soil compaction and vegetation cover

The increasing incidence of soil degradation requires monitoring strategies adapted to the scale of interest. We propose an innovative approach to the large-scale investigation of predominantly green areas where healthy vegetation is the clue to identifying vital and protected soil. We started with the well-established environmentally sensitive areas (ESA) model, which provides an evaluation of overall land vulnerability that is based on structural, biophysical and socio-economic indicators. To improve the estimation of soil vulnerability, we integrated information on the potential extent of compaction caused by agricultural machinery. To differentiate the degree of degradation in areas that show similar potential vulnerability we included information on the temporal variation of photosynthetic activity in the model for early detection of the soil's reduced ability to carry out ecosystem services and functions. Satellite data were used to obtain vegetation cover properties to integrate into the ESA model to improve estimation of land degradation in southern Italy, where both natural and agricultural areas are widespread. Inclusion of the temporal dimension is essential for discriminating between different degrees of soil productivity in areas characterized by similar structural conditions. Our procedure is adaptable, user-friendly and easily transferable.