Evaluating land suitability for spatial planning in arid regions of eastern Iran using fuzzy logic and multi-criteria analysis

The accurate evaluation of ecological resources plays a critical role in optimal planning for spatial development. For its study of an area of about 11.6 Mha, the present research aimed to assess land suitability in arid regions of eastern Iran by employing a fuzzy inference system in a GIS environment. Primary data, such as the physical properties of soil, climatic factors, elevation, land type, vegetation cover, and faults, were investigated and a geomorphologic map was drawn for working units and planning. In addition, a layer of soil erosion potential was extracted according to the CORINE model. As each environmental element poses a different effect on other parameters, the significance and impact of each factor were first prioritized by a multi-criteria decision-making method. Then, a fuzzy inference system was employed to create a land suitability map for the study area. With the Mann-Whitney non-parametric test, the achieved map was adapted to the land reality. Without considering the potential of soil erosion in areas where agricultural and residential land have currently been developing and expanding, the results showed that locational development is possible in 70% of the region (an area of about 8 million hectares). However, when considering the assessment of the soil erosion potential and inappropriate climate and environmental conditions in 81% of the study area, only 10% of the area allows for the development of spatial-economics. Given that the purpose of this research is founded on risk management, the results can be considered by developers for future ventures.