Assessment of soil erosion at national level: a comparative analysis for Spain using several existing maps

Soil erosion has been recognised as a critical environmental issue leading to soil degradation and desertification in Mediterranean areas. Due to the seriousness of the environmental and socio-economic impacts associated to the process at different scales, many studies have faced the process at global, national, regional and local levels. At national level, the quantification and assessment of soil erosion is a basic step to elaborate and promote environmental policies that help decision-makers undertake appropriate action in combating soil erosion and its consequences. Adequate application of such policies on the basis of a spatial knowledge of the process is crucial to maintain and even improve the quality of soil resources. However, the analysis of some existing cartographic documents reveals some discrepancies. A comparison of several studies (ICONA, CORINE and GLASOD) assessing soil erosion at national level in Spain has been carried out. The analysis using the maps of soil erosion presented by these studies shows differences in the spatial representation of the process. This may be due to the different methodologies, input data and scales used.