Multi-Criteria Evaluation Model for Desertification Hazard Zonation mapping Using GIS (Study Area: Trouti Watershed, Golestan, Iran)

Desertification is one of the major issues threatening human communities. Many methods have been developed for assessment and mapping of desertification hazards. In this research, multi-criteria evaluation method was used to investigate desertification process in Trouti watershed, Golestan Province, Iran. At the first step, major desertification factors were determined by doing field surveys. They were soil texture, aspect, rainfall, sensitivity of geological formation to erosion, hydrologic soil group, slope and land use. The next step, information layers were digitized in GIS environment and Digitized maps were converted to fuzzy standard maps using fuzzy membership functions in IDRISI software. Then, weight of each factor was determined with the contribution of Analytical Hierarchy Process. Finally, the susceptible areas to desertification in the study area were identified using Multi-criteria evaluation method. The results showed that 36.55, 15.21, 40.17 and 8.07 % of the study area were classified as severe, high, moderate and slow affected by desertification, respectively. It was concluded that land use and sensitivity of geological formations to erosion were the most important factors affecting desertification process in Trouti watershed of Golestan Province.