Wildfires in desertification prone areas: analysis at a regional scale

Abstract

Desertification represents a rea1 risk to many Italian regions, in particular to southern and insular ones. Wildfires are a serious disturbing factor, greatly contributing to desertification. After the fire a temporary reduction of the vegetal covering capacity and modifications of the soil chemico-physical pararneters are actually produced, thus leading to an increase of soil erosion. These modifications appear to be particularly worrying in arid, semi-arid and dry sub-humid areas, typical of the Mediterranean area, where they bring about a significant increase of the risk of desertification. Many researches have been realized on this subject, but often disregarding wildfires. The present work aims at investigating at a regional scale wildfire action in desertification prone areas. Two regions, Liguria and Sardinia, were chosen as study areas, planning three research levels, concerning wildfires, land cover and erosion. Crossing the results of these research levels, it was possible to assess at a regional scale wildfire impact on erosion, considered as one of the main factors acting in land degradation. An algorithm was set in order to assess mean annua1 increase of soil loss due to wildfires for each municipality. The method proposed allows to appraise the problem at a regional scale and to provide a useful support tool for wildfire management planning.