A coupled empirical approach for rainfall and land use correlation to landslide occurrence in the Esino river basin, central Italy

Abstract

A coupled empirical approach for studying possible correlations among rainfall, vegetation segmentation and landslide occurrence is discussed. To reveal such links two important rainfall events, occurred over the Esino river basin in central Italy, in November 2013 and May 2014, were analysed. The correlation between rainfall and landslides was carried out applying an intensity–duration (ID) threshold method, whereas the correlation between vegetation segmentation and landslides was investigated using the Morphological Spatial Pattern Analysis (MSPA). This coupled approach represents an attempt to find both timing and location of landslide occurrence through an empirical (black box) analysis. Results showed that: (i) the ID minimum threshold proposed in a previous study (Gioia et al., 2015) was verified as an effective equation to assess the rainfall conditions likely to trigger landslides in the study area ("when"), and (ii) the Core areas and the fragmented vegetation structures defined by the MSPA were the most affected by slope failures ("where"). These encouraging findings prompt for additional testing and application of such coupled empirical approach to possibly achieve an integrated basis for landslide forecasting.