Evaluation of the susceptibility to landslides through diffuse logic and analytical hierarchy process (AHP) between Macas and Riobamba in Central Ecuador

Susceptibility to landslides is one of the geological hazards that most frequently occur along the roads and hereby mainly in those situated in mountainous areas. Through multicriteria studies it is possible to determine critical points, however, these are generally deterministic, so new methodologies that offer a probability of occurrence in the entire study area are sought. The Fuzzy method is a probabilistic technique that is based on the observed to emulate the thinking of the human being and generate an artificial reasoning. Therefore, the main objective of the current study has been to evaluate the susceptibility to landslides through Fuzzy Logic in combination with the Analytical Hierarchical Process (AHP) in the Macas - Riobamba road. This should allow to define critical points in such road. We applied five variables being slope, precipitation, proximity to rivers and roads, as well as vegetation cover. The spatial data were transformed to raster to later standardize their values. With the support of membership functions, the membership of each variable was established to finally perform the weighted sum and obtain the resulting model. Three models were obtained with AHP and one without this, whose adjustments were 84.1%, 87.1% 89.5% and 60.3% respectively. We identified that the susceptibility to landslides is in the part that crosses the Andes mountain range, with critical points in four specific sectors. With Fuzzy Logic it was possible to generate susceptibility maps, which support make decision processes.