A Combined AHP- and TOPSIS-Based Approach in the Assessment of Desertification Disaster Risk

Abstract

In this study, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and Analytic Hierarchy Process (AHP) methods were used to determine, prioritize, and assess the most effective desertification indices. A list of 32 influential indices was identified using existing literature in Iran and around the globe through questionnaires. Criteria for evaluating indices were weighted using Shannon entropy, and then TOPSIS ranking method was applied to determine the most effective desertification assessment to deal with this issue in Kashan region, Isfahan province. Indices were weighed and prioritized by analytics hierarchy process. Finally, the Mediterranean Desertification and Land Use (MEDALUS) model was used to assess the intensity and develop a desertification risk map. The results asserted that sensitivity to minor changes with a weight of 0.341 has the highest importance, while time and cost with a weight of 0.11 has the least importance for the evaluation of indices. Among the 32 ranked indices, 20 of which were identified as the most effectual indices including annual precipitation, salinity, and vegetation, to name a few. The results also showed that the land use change index with a weight of 0.217 and annual rainfall with a weight of 0.166 have the highest priority among human and natural indices that should be prioritized in managing and controlling desertification. The average weight of quantitative desertification intensity for the whole area was 1.391 placed in critical (1) class of desertification. Among the six considered desertification criteria, the climate and the destruction of water resources were the most important criteria.