Determining Geomorphological Restricted Areas in order to Locate Appropriate Directions of Urban Development from a Risk Perspective (Case Study: Bojnourd City)

Unplanned human activities in the environment lead to various risks and damages from human, social, environmental and economic aspects that can have catastrophic effects and consequences with the help of planning and preparedness for emergency measures. The purpose of this study is to determine the geomorphological restricted areas in order to locate suitable aspects of urban development from the perspective of risk in urban and suburban areas of Bojnourd. With this aim and in the systemic approach, environmental variables including geomorphological parameters, geology (lithology and active faults), topography (slope, slope direction and altitude), hydrology (distance from rivers and canals) and human parameters (Land use and distance from urban and demographic points) in the study area in the form of classification maps and layer fuzzy operation was performed. Using the ANP model, the final weight of each factor layer in the Super decision software was obtained. From the multiplication of the final weight obtained from the ANP model with fuzzy layers and using the Fuzzy Gamma 0.5 operator, an integrated map was obtained and the geomorphological restricted areas were identified from the perspective of urban development and the remaining areas of the study area into appropriate and very inappropriately categories were classified. The results showed that 57.7 KM2 equivalent to 21.24% of the study area, according to the existing standards and conditions, is a restricted area, which often corresponds to the eastern, northern and northeastern parts of Bojnourd that is, the bed and river bed privacy of Firoozeh river and the intersection of Halghehsang, Malkesh, Pesteh, Doberar, Aghghaleh, Gheshlagh, Langar, Baghchegh , Aliabad canals and the adjacent points of the Chaharkharvar-Babaaman, Doberar-Borj fault systems and the torn and hidden fault that it corresponds to the bed of Firoozeh river. Of the total area of the study area, 58.3 KM2 equivalent to 15.84% includes the very suitable areas, which are mostly in the central (old army barracks), southern (upstream lands of the Mantagheh barracks, Maleksh and Takhte Arkan), southwestern (old police station) and south eastern parts (Hamzanlu, Kalateh Yavarie and Farhangian town) in the research area and therefore, considering the current area of Bojnourd, there is an optimal development space for the coming years based on moving in a low-risk path. The final conclusion is that the present study is based on a systemic approach and the application of geomorphological restricted areas and the research results for space management have the residential development efficiency for urban and suburban areas.