A new shallow landslides inventory for Southern Lunigiana (Tuscany, Italy) and analysis of predisposing factors

A new inventory of shallows landslides for a study area located within Southern Lunigiana valley has been obtained by means of digital visual interpretation of orthophoto maps acquired in the years 2003, 2007, 2010 and 2013. A total of 331 shallow landslides occurred during the decade 2003-2013 have been identified, resulting in an average landslide density of 1.1 landslides per square kilometers. A spatial analysis has been implemented to investigate landslide distribution in respect to predisposing factors: bedrock geology, land use and morphometry (elevation, slope steepness, flow accumulation, slope aspect). Results highlight that bedrock lithology and land use are important factors affecting shallow landslide distribution. While all the morphometric parameters analyzed are correlated to shallow landslides density, slope aspect seems to be the prominent conditioning for landslide occurrence.