Land subsidence susceptibility mapping using WALPSRFT model and Fuzzy- AHP method (Case Study: Damaneh-Daran Plain in the west of Isfahan Province)

The phenomenon of land subsidence, which is affected by human activities and various geological and hydrogeological parameters, is occurring in different parts of Iran. Land subsidence susceptibility mapping is a necessary prerequisite for land subsidence management. Proper assessment of land subsidence requires the determination of parameters affecting land subsidence to discover the spatial relationships between them and land subsidence. For this purpose, first, according to the land site subsidence, eight parameters affecting the subsidence in the Damaneh-Daran plain, two models were prepared. In the first model, eight parameters including annual groundwater level drawdown, aquifer medium, land use, pumping volume, aquifer thickness, net charge, distance from fault and topography called WALPSRFT based on weighting parameters and the second model based on optimization and compatibility of eight effective layers in subsidence, Was prepared by AHP-Fuzzy2 method and the final map of land subsidence vulnerability was obtained by combining layers in ArcGIS. Radar images and a Radar Interferometer (InSAR) were used to validate the models. The results show that both maps show a good correlation with radar data, and the map prepared by the hierarchical-fuzzy method shows the highest correlation with real radar data and subsidence in the plain. It separates in more detail on the whole surface of the plain. According to this model, most areas of the plain, especially the eastern part, are subject to subsidence, and management programs should be considered to control subsidence.