Statistical analysis for assessing shallow-landslide susceptibility in South Tyrol (south-eastern Alps, Italy)

This paper conducts a statistical analysis to determine shallow-landslide susceptibility in an approximately 7500-km2 region of the south-eastern Alps (South Tyrol, Italy). The study applies the weight of evidence (WofE) method, which is useful in determining landslide susceptibility in large areas with complex geological and geomorphological settings. The statistical analysis and landslide susceptibility mapping are based on 882 past landslides, three geometric/topographic factors and two anthropogenic factors, which are the most relevant landslide predisposing factors. The quality of the proposed model, particularly the fitting performance, was assessed; the landslide database was divided into a training set to obtain the model and a validation set to estimate the model quality. The results show that the developed susceptibility model predicts an acceptable percentage (75%) of landslides. Therefore, the model can be useful and reliable for land planners and decision makers also due to its cost-effectiveness ratio.

► The analysis is based on the application of the WofE (Weight of Evidence) method. ► The predisposing factors have been selected using past landslide inventory. ► Results provided a sound basis for shallow-landslide susceptibility mapping. ► Results reach an acceptable percentage (75%) of correctly predicted landslides.