An expert system to evaluate environmental sensitivity: a local-scale approach to land degradation

Under scenarios of increasing climate aridity and human pressure, Ecosystem Sensitivity to Desertification (ESD) is one of the most important targets for sustainable land management. This process is particularly complex in the Mediterranean region since it involves multifaceted, interacting factors that depend on endogenous conditions and exogenous pressures. Environmental indicators quantifying the ESD level at local scale should reflect the interaction among biophysical and socioeconomic factors that are (directly or indirect) associated to soil and land degradation. This paper illustrates a Geographical Information System (GIS) investigating the main factors determining ESD at land unit scale. This tool incorporates a Decision Support System (DSS) capable to simulate the effect of short-term environmental changes on the ESD (hereafter ‘DSS-ESI’). The final output of the DSS-ESI is a composite index of land sensitivity to desertification (ESI) calculated separately for representative land cover types. The illustrated system was supplemented by a web-based interface which estimates the overall level of land sensitivity under different climate, population, and policy scenarios. The paper illustrates the main results produced by the DSS-ESI in a study site application (Basilicata, Italy) and comments about its applicability to other Mediterranean areas. Monitoring systems like the one illustrated here may support local-scale responses to mitigate land degradation in the Mediterranean basin.