Document Type : Research Paper

Authors

Abstract

One of the major consequences of desertification is development of destructive floods in spite of ground water level falling in the lower parts of basins, which will lead to water quality/ quantity decline, landslide and blending of saline and fresh water tables. Each of these symptoms individually or in combination with the others clearly notifies the development of desertification. Identification of suitable areas for flood control will assist the natural aquifer recharge in the basin’s upstream and will reduce the development saline and gypsiferrous waters in the ground water of basin’s downstream and surrounding area, which in turn will cause secondary salinization in the lower parts of basins. Off course computer models are the most suitable methods for determination of the best sites in this regard, and because of variety of available models in the first step we should determine the best model. In this research compiling of effective factors using establishment of information layers and then regionalization in conceptual models which were applicable in GIS media like as Boolean logic model, overlap index model and Fuzzy logic model was used. The main research technique is analytical comparison of results using these models. These models were done in GIS media by scoring to the variables affecting flooding and aquifer recharge based on their effectiveness. We compared models due to natural conditions of the region to determine the best model for quantitative analysis of flooding in 6 towns of Khorasan-e-Razavi province, with emphasis on determination of flood control capability of these regions to combat desertification. Results showed that Fuzzy model with summation operator gives the best adaptivity compared to the other models to determine the floodable and capable for flood control areas.
 

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