A GIS and frequency ratio based landslide susceptibility mapping: Aghnashini river catchment, Uttara Kannada, India

摘要

Landslides are encountered during the monsoon season in the undulating terrains of the Western Ghats, resulting in significant damage to life and property. Here landslide susceptible regions are modelled in the Aghnashini river catchment of Uttara Kannada district of Karnataka, India, using the frequency ratio method. Factors that influence landslides like slope, aspect, distance from roads and lineament, soil depth, soil type, and Land use and land cover, were extracted from the spatial database. Using the factors and detected landslide based on the field work, the relationships were calculated using frequency ratio, one of the probabilistic model of frequency ratio model. The computed index for each grid for each factor was summed and grouped into five classes. The susceptibility in the region with Argillit, clayey-skeletal, slope greater than 45, slope facing Southwest having grassland showed highest susceptibility. The landslide-susceptibility map can be used to reduce damage associated with landslides and to land cover planning.