evaluation of the effects of soil properties on desertification (case study: segzi pediment of isfahan, iran)

one of the characters in iranian model of desertification potential assessment (imdpa) is soil. since soil is very important in the degradation of land, so some indices were determined for this character in order to evaluate desertification potential of arid, semi-arid and dry sub humid areas of iran. the indices included soil texture, deep gravel percentage, soil depth, and ec. to calibrate the soil character of the imdpa, above mentioned indices were assessed in segzi pediment as arid region. to do this, in first stage, map of the study area was prepared based on slope, land use and geological maps. scores of indices were recorded in different study units. at last, using the formula, si= , final score of soil indicator (si) was determined in the study area based on imdpa. in this model, desertification potential classes are low, moderate, high and very high. the map showed that 1.5%, 20% and 78.5% of the study area are considered as medium, high and very high desertification intensity classes, respectively. more over, there wasn't low class based on vegetation character.