The Role of Natural Factors in Instability of Rural Settlements in Mountainous and Foothill Areas of Zagros (Case Study: Villages of Marivan and Sarvabad Counties)

Historically, natural factors have been effective on the establishment, type of livelihood and displacement of populations, and the example of its influence can be seen clearly in the instability of rural settlements, This study was conducted to investigate the role of natural factors in the instability of rural settlements in Zagros mountain and foothill (case study:Villages of Marivan and Sarvabad Counties). In this study, 9 factors (climate, altitude, slope, fault, rivers, landslides, lithology, erosion, land users) were used, Layers of these factors were provided in ARC GIS environments .and weighted by using Expert choice software And by adding weights to AHP model in ARC GIS and overlapping layers, the stable, semi stable and unstable villages were specified.The research method was descriptive - analytic method, and ARC GIS software and Expert choice were used, The results showed that out of 229 settlements in the study area, about 24 villages (10/48%) were located in stable zone, 58 villages (32/28%) in the range of semi-permanent, And 147 villages (64/19 percent%) are located in unstable areas, In general, the under study area in terms of environmental - ecological factors is considered as unstable, Therefore, Fundamental and serious attention to these factors in order to avoid the risks and preventing the loss of capital in any planning, seems to be necessary