desertification evaluation using imdpa model (case study: taraz nahid, saveh, iran)

several studies have been performed to evaluate the desertification in iran andother countries which led to present national and regional models. one of them is imdpamodel. this model was used as a case study in taraz nahid, saveh, iran. in this study, fivefactors including climate, soil, vegetation, irrigation, and socioeconomic ones wereevaluated. according to the region conditions for each criterion, several indices wereconsidered. based on the selected indices for each criterion, the qualitative maps weredeveloped from geometric mean of indices for each criterion and finally, the desertificationintensity map was prepared from the geometric mean. the final desertification map showsthe balanced (moderate) and intense (severe) classes of desertification process in theregion. according to the performed evaluations, the soil texture index with the averagevalue of 3.75 (very severe class) and vegetation conditions with the average value of 2.9were more effective indices in the region desertification. also, the desertificationquantitative intensity value (dm=2.31) was calculated for the entire study region thatshowed the moderate class for this region.