Study the Feasibility of Physical Expansion of Sarab City in Relation with the Natural Environmental Factors

Today, the irregular process of urban extension and urbanization in relation with the increasing population growth has led to harsh and unfavorable conditions in the environment. So, professional urban planners and managers have special attention to the establishment and development of cities for maintaining the ecological balance of urban and suburban areas, trying to minimize the environmental damages caused by the physical expansion of cities. It is clear that the first step for achieving this goal is to recognize correctly capabilities of natural environment for establishment and next development of city to surrounding areas. This study was done in this regard, aimed to assess favorable and unfavorable environmental opportunities for physical expansion of Sarab city. The data of selected variables including elevation, slope, lithology, distance from fault, distance from stream, soil type and ground water depth came from various library references. Research method is descriptive-analytic and we used the fuzzy multi-criteria decision making model to determine the favorable/ unfavorable areas for physical expansion of the city. In this regard, preparation, management and analysis of data are performed by geographic information system (GIS). Results of overlaying analysis by gamma fuzzy 0.9 operator in form of final land suitability map indicated that there is a little difference in area percent between appropriate (38%) and inappropriate (42%) condition for the physical expansion of the city. Although Sarab city is encountered with impasses from the south in terms of natural environment for physical expansion, but expansion capabilities is suitable from the East, the West and particularly the North. Given natural environment conditions of the study area, special attention is necessary to surface and ground water resources in this regard.