GIS – Based Landslide Susceptibility Mapping Using Fuzzy AHP – Multicriteria Evaluation Method for Rudraprayag District, Uttarakhand

Landslides are one of the common and widespread geological disasters, causing significant losses of lives and assets, particularly in mountainous landscapes. Therefore, in order to manage, prepare and mitigate landslides, landslide susceptibility maps are crucial. Thus, the main goal of this study is to generate landslide susceptibility map of Rudraprayag District, Uttarakhand, India which is one of the most prone areas to landslides in the country. This research employs GIS-based multicriteria decision analysis (MCDA) with Fuzzy AHP for assessing the susceptible areas to landslides in the study area. Initially, location of landslides that occurred in the past were identified using Disaster Management and Mitigation Centre, Uttarakhand and Google Earth Images. A total of 130 landslides were mapped. Then, the landslide inventory was classified into two parts; 1. 70% training and remaining 30% for validation. Ten landslide conditioning factors were selected to produce landslide susceptibility map using FAHP – MCDA in GIS environment. For assessing the reliability and accuracy of findings, Receiver Operating Characteristics (ROC) and Area Under the Curve (AUC) approach were used. Findings reveal that fuzzy statistical approach is able to predict 78.1% results precisely. Produced Landslide Susceptibility Map (LSM) was classified into three classes, i.e., Low, Moderate and High. Areas with high landslide susceptibility are largely found in the northern and eastern part of the district and these areas are marked by high altitude, steep slopes, major fault lines and high drainage density. This study will aid planners and policymakers in emergency decision-making, mitigating future landslides and studying their underlying causes.