Using Boolean and fuzzy logic and weighting factors for landslide and sediment hazard analysis in the watershed of Chelgerd- Chaharmahal and Bakhtiari Province

Erosion such as landslide is phenomenon that causes wasting of many water and soil resources and destructing natural resources. The objective is landslide hazard mapping. Landslide can be the main source for sediment supply. The region was Chelgerd watershed in Shahrekord. For landslide hazard mapping, information layers including slope, elevation lithology, land use, distance to road, distance to stream, distance to fault and to springs as effective parameters of landslide have been recognized and digitized. After fuzzy standardizing of constraints and factors by methods fuzzy and Boolean weighing factors using the analytic hierarchy process (AHP) was incorporated. Final phase, landslide hazard zonation map was prepared. Results show that 49 percent of studied land are high and very high risk zones located. In this study, the most landslides occur in 500 meters from road and 400 meters from Stream with dip ranging from 15 to 50 percent at the elevation of 2600 meters moreover, agricultural lands and gardens within Khankat and Neyriz formation contain the most landslides. Since the possibility of landslide in the vicinity of roads and Stream, with medium dip is very high. It is necessary to be considered in managing of the area.