Assessment of desertification hazard by using the 9 criteria IMDPA model in Semi-arid Agh-Band region, Golestan Province

Desertification is one of the most important concerns and a major threat for natural resources and human societies. In this study, IMPDA model have been applied to assess desertification hazard in semi-arid Agh-Band region, Golestan Province. Work unit map was provided using geology, land use maps, aerial photos and satellite images. Desertification hazard was mapped using 9 desertification criteria including: soil condition, geology, climatology, land cover, Socioeconomic status, groundwater, urban development, agricultural and water and wind erosion with 26 desertification indicators. For each major criteria affecting quality indicators investigated and via IMPDA method weighted with geometric mean calculation and using ArcGIS 9.3 software, maps relative to position of each criteria were provided. At the end, map of sensitive zone to desertification was provided using geometric mean. The differences were compared between hazard classes with Chi-square and Mann-Whitney test for evaluation of models accuracy using the Minitab software. Results of chi-square test indicated that there is an appropriate differentiation among hazard classes. The results showed that 17.7 percent of the area is classified as high class and 51 percent as moderate affected by desertification processes. Further analysis indicated that the land cover and soil condition criteria are the most important criteria of desertification process in the Agh-Band region.