Modeling Landslides Using Analytical Hierarchy Process (AHP) and Geospatial Techniques to Mitigate Hazard Risks in the High Mountain Himalayan Landscapes of Sikkim and Darjeeling, India

Sikkim and Darjeeling Himalayas are prone to landslide hazards due to their complex geo-environmental settings and increasing human interference with the natural environment. Landslide damages both life and properties in the affected areas. Prior identification of landslide susceptibility zones is a prime requisite for the effective planning and management of landslides. The present study tries to delineate potential landslide zones based on eight causative factors including slope, rainfall, drainage density, Geomorphology, Lineament density, Soil, Geology, and Land use and Land cover. The Analytical Hierarchy Process (AHP) was utilized to provide weights and ranks to these factors which were integrated with geospatial techniques for the generation of the landslide susceptibility zonation map. The findings revealed that the moderate landslide susceptibility zone dominates the region with 15.72% area covered under it, followed by low to very low 26.66% and high to very high 15.72%. The overall consistency ratio values of 0.065 and the AUC value of 85.7% validate the consistency in providing weights and accuracy of model prediction, respectively. The present study will provide information for the proper implementation and management of landslide hazards in the future.