Surveying of Iranian Model of Desertification Potential Assessment

Drylands occupied a large area of lands on Earth and a large percentage of the population are living in these areas. Land degradation or desertification is one of the biggest problems in arid zones. In general، little effort for mapping land degradation at regional to global scales has been made. Recent efforts to assess desertification in Iran led to devise the Iranian Model of Desertification Potential Assessment or IMDPA. In this article we intend to consider the concerns of international models of desertification، re-evaluate the Iranian Model of Desertification Potential Assessment in the East of Esfahan and Studies carried out on this model till now to review and to evaluate indicators of the soil، vegetation and erosion in the IMDPA. Our aim in this paper is to clarify many of the black spots of desertification in Iran، we''re going to show where to start and what to expect on a study of desertification. In this study، water، soil and vegetation indicators and their indices in 172 homogeneous work units were assessed using the instruction of IMDPA، and the results were compared with a study done in the 90s. According to land degradation and desertification studies we propose a model as «Iranian Model of Desertification Status Assessment» or IMDSA be created in which the three indicators of land degradation، namely the degradation of soil، vegetation and water can be used on it. According to our study، to indicate soil degradation state، the four indices of Tillage Pan، Infiltration، Aggregate Size Distribution and Score of EC and to evaluate vegetation degradation status، the four indices of Alien Invasive or proliferous weed species، Biomass decline، Bare Spots، and proportion of useful species for use in the Iranian Model of Desertification Status Assessment were appropriate.