Application of Frequency Ratio Method for Landslide Susceptibility Mapping in the Surkhob Valley, Tajikistan

Abstract

In the valley of the Surkhob River, manifestations of modern geological pro- cesses, characterized by various forms of manifestation, are widely developed. Studying these processes is of utmost importance, primarily landslides, which are directly related to the loss of stability of rocks on the slopes. Landslide processes in the Surkhob River valley, regardless of their type, cause signifi-cant economic damage to the population and the economy, as well as nega-tively impacting human living conditions. The primary goal of this project is to map landslide susceptibility using a geographic information system and quantitative and semi-quantitative methods. Landslide susceptibility assess-ment of this research was conducted using slope (degree), aspect of the slope, curvature, stream power index, topographic wetness index, precipitation and altitude. Except for precipitation, which was collected from the world climate site, most of the causal elements were derived from DEM from the SRTM (Shuttle Radar Topography Mission) database, with cell sizes of 30 m 30 m. 416 landslides were discovered from satellite pictures of Google Earth Pro and then validated in the field to analyses the link between causative factors and landslide inventory. To measure the weights of each causal element, the frequency ratio (FR) and the analytical hierarchy process (AHP) were used. The quality of the landslide susceptibility map was determined using the Re-ceiver Operating Characteristics curve (ROC), and the AUC value was deter-mined to be 0.877. It is possible to use the landslide susceptibility map as an engineering and geological basis for establishing a national economic devel-opment plan for the territory of the Surkhob River valley.