Landslide susceptibility mapping using GIS along the Niš-North Macedonia highway

Landslide events are a serious challenge worldwide, as well as in the Republic of Serbia. According to current estimates, 25-30% of the territory of Serbia is endangered by landslides. Due to intensive landslides, residential, infrastructural, energy, water management and industrial facilities, as well as natural and cultural goods are endangered. The subject of this paper is the use of GIS for the production of a landslide susceptibility map (LSM) in the area of the corridor of the highway E-75, section Niš - border of the Republic of Northern Macedonia. Emphasis is placed on the analysis of certain factors that influence the landslide events, as well as on the modifiers of the process itself. In this paper the following factors were selected for the assessment and susceptibility mapping: lithology, pedological factors, precipitation, aspect, slope, distance from watercourses, land use and distance from roads. The AHP method was then used to determine the relative significance and priority of predisposing factors. The layers were overlapped using ArcGISPro software. The results show that 17.2% of the surface is not susceptible (very low and low susceptibility), and 31.9% of the surface is prone to landslide events (high and very high susceptibility). The remaining 49.1% of the area belongs to the area of moderate susceptibility. Adding to this dense road network in the study area, as well as a large number of populated places, it can be concluded that the damage from the activation of the landslide would be significant. The results suggest that 60.7 km of the highway is in an area of high and greatest risk of landslides.