Evaluation of landslide situation in Kohdasht city using model (ELECTRE-1)

One of the main reasons for the occurrence of landslides is the mismanagement of the earth, especially in mountainous regions and valleys. In this research, we tried to investigate the factors affecting the occurrence of landslides and also comparing sections of Kuhdasht city in terms of landslide susceptibility in the form of multi-criteria decision making method (ELECTRE-1), areas with high risk of landslide hazard. The application of multi-criteria electric methods is in the ranking. The model (ELECTRE-1) evaluates the decision matrix, which includes m options and n indexes. In this research, the choices, parts of the city of Kuhdasht, and indicators are the factors influencing the occurrence of landslides. After weighing, comparing the pair and calculating the final weight of the factors, it was found that the gradient factor with a weight of 0.379 and a petrology with a weight of 0.248 have the main role in the sensitivity of the study area. The area was also assessed for the extent of the vulnerability to landslide. According to this assessment, Tarhan and Romeshgan sections (with the number of domination 2) have the highest risk for the occurrence of landslides and then, respectively, sections of Kohnani (with the number of domination 1), the Darbe gonbad and Central (Without the number of domination). The average weight of the factors according to the harmonized criteria is for the sections of Tarhan (0.427), Romeshgan (0.0412), Kohnani (0.359), Darbe gonbad (0.0253) and central (0.217). Among the factors that cause the sensitivity of the parts of the Tarhan and Romeshgan, the percentage of sensitive slopes (15 to 45 degrees), the petrographic situation (with the overcoming of lime and marl), the use of inappropriate land and hydrographic network can be mentioned.