Land Suitability Analysis for Physical Urban Expansion of Sabzevar City using the Fuzzy Analytical Hierarchy Process (FAHP)

During the last decades, rapid urban population growth resulted in physical development of cities. This population explosion and its resulted unplanned development, specifically in developing countries, lead to adverse consequences such as construction in agricultural land and approaching and settlement in areas exposed to natural hazards. Using various criteria, land suitability analysis (LSA) could be an important proceeding to accomplish sustainable and safe urban development. GIS, with the ability of analysis of spatial relationships, helps urban policy makers to relate different information sources and perform sophisticated analysis. The present study deals with land suitability analysis of the central county of Sabzevar to reach urban development‚ considering eight criteria, i.e. slope, height, aspect, distance to fault, distance from main roads, distance from surface water, land cover, and soil type‚ using fuzzy analytic hierarchy process (FAHP). In this method we calculated land suitability index for the studied area with selecting different criteria, defining the weight of each criterion, producing criteria maps in GIS environment, and finally integrating them. Eventually final map was classified into five class of much higher, high, medium, low and much lower suitability. The results showed that about 60% of the evaluated scope is in high and much higher suitability overall and also 16% of the scope is in the areas of low and much lower suitability that the major cause of this unsuitability can be the existence of Joghatai Mountains in the north of the area. According to the research, North‚ East and North East of the city are the most suitable directions for urban development.