Evaluating Desertification Intensity with Emphasis on Groundwater Criteria Using IMDPA Model (Case Study: Mehran Plain in Ilam Province)

Desertification is defined as the reduction of the ecological and biological potential of the earth, which occurs both naturally and artificially. This phenomenon is one of the important problems of countries for sustainable development management programs, which is the result of a combination of various environmental, human and climatic factors. Water is recognized as an important and influential factor that is the main source of life and also guarantees the survival of sustainable ecosystems. Since water is more important in arid and semi-arid climates than in other climates, measures should be taken to properly manage water in order to prevent critical conditions in these areas. The purpose of this study is to investigate the status of water criteria to assess desertification. Due to the many effects that water indices have on the development of desert areas, in our study, we used quantitative and qualitative indices of groundwater such as electrical conductivity (EC), sodium absorption ratio (SAR), color (Cl), falling groundwater level and irrigation systems to study and determine the class of desertification intensity in Mehran plain. The IMDPA model was applied to evaluate the desertification situation. The results showed that the indices of decline and irrigation systems with average values of 3.11 and 1.75, respectively, have the greatest impact on the desertification process in the region. According to the groundwater status map in the destruction of resources in the study area, it can be concluded that 32% of the total area is in the low class, 48% in the middle class, and 20% of the total area is in the severe desertification class. In general, water resources management should be a priority for executive agencies to prevent desertification.