Landslide susceptibility zonation of a hilly region: A quantitative approach

Abstract

Categorization of landslide susceptibility holds great significance in hilly regions as it is one of the regularly occurring natural hazards that brings massive devastation to life as well as property. Detection of such landslide susceptible areas is regarded as a useful input for policymakers who plan various developmental activities in those areas. The present study considers Pabbar Catchment, located in the state of Himachal Pradesh, India as the study area and prepares a Landslide Susceptibility Map (LSM) for it using the Frequency Ratio (FR) technique. Eleven geo-morphological aspects of the catchment called ‘causative factors’ were used in thematic form for building the LSM. Being a quantitative method, FR functioned satisfactorily as the prediction accuracy came out as 0.825 in the Area Under Curve (AUC) of the Receiver Operation Characteristics (ROC) process. Approximately 7.48% of the geographical area from the catchment falls under the ‘very high’ landslide susceptible zone, 37.31% under the ‘high’ category, whereas 35.34% of the area comes under the ‘moderate’ susceptible zone. The results shall be advantageous for similar kinds of investigations as well as for planning and development authorities.