A Combined Model for Landslide Susceptibility, Hazard and Risk Assessment

This paper proposes a combined model for landslide susceptibility, hazard and risk assessment based on a spatial prediction method and the fuzzy sets theory using geographical information systems (GIS). To evaluate landslide susceptibility and hazard in the study area in the northwest of Iran, the first step was the construction of a database, which includes three different data groups namely conditioning and triggering factors and the landslide inventory data. A landslide susceptibility model was constructed by using favorability function method and conditioning data. The selected landslides were of moderate to high intensity, which had occurred or reactivated at least once over the last 55 years. Landslide susceptibility map (LSM) was transformed into landslide hazard map (LHM) by using the regional seismic and precipitation data. Desirably, the accuracy of susceptibility and hazard models were determined 84.9% and 84.8%, respectively, by using the receiver operating characteristic (ROC) curve method. Layers of the landslide hazard potential (LHP) and resource damage potential (RDP) were integrated based on the fuzzy algebraic product operator in order to determine the risk level due to landslides. Lastly yet most importantly, the results of the study were integrated in the risk prevention and land use planning.