Landslide Susceptibility Mapping for Yadak-Tevil Watershed (Northeast Iran), Using AHP Method

Abstract

Landslides form major natural hazards in hilly terrain in the area, and caused extensive damages to road, human dwellings and agricultural lands. There is still a great danger of further landslides in the region. Therefore, it is important to prepare a landslide susceptibility map of the region. In this study a landslide susceptibility map of Yadak-Tevil watershed was prepared using the Analytical Hierarchy Process (AHP) with the help of GIS. For this purpose, thematic layers including landslide inventory, lithology, distance from drainage, slope, slope aspect, and elevation were the main contributory factors to be considered for landslides susceptibility zonation. The landslide susceptibility map was classified into four different landslide susceptibility classes. The four landslide susceptibility classes are: low 16.13 % (33.50 km2), moderate 33.34 % (69.38 km2), high 33.00 % (68.68 km2), and very high 17.53 % (36.48 km2), respectively. Results of this study show that the AHP method is precise method for evaluation of landslide potential due to the use of binary comparison affecting factors and considering numerous factors for landslide evaluation at the same time in comparison to the other prevalent method.