GIS-Based Landslide Susceptibility Mapping in Eastern Boundary Zone of Northeast India in Compliance with Indo-Burmese Subduction Tectonics

Abstract

The Eastern Boundary Zone of Northeast India, comprising the Indian States of Manipur, Mizoram and Nagaland, suffers immensely under the impact of frequent devastating landslides that results in widespread damage and casualty. A rough estimate of the decadal intensity of landslides from an inventory spanning over half a century calls for systematic assessment of landslide hazard and risk in the region for its effective mitigation and management. Landslide Susceptibility Zonation is the most fundamental step in that direction wherein spatial distribution of Landslide Susceptibility Index (LSI) is established through integrating nineteen causative factors, viz. surface geology, landform, lineament density, elevation, distance to lineament, slope angle, aspect, drainage density, distance to drainage, terrain ruggedness index, plan and profile curvature, normalized difference vegetation index, landuse/landcover, distance to road, road density, rainfall, earthquake epicentre proximity and peak ground acceleration rationally on GIS platform in 1:50,000 scale by following a multivariate statistics-based Logistic Regression (LR) procedure. This classifies the terrain into None, Low, Moderate, High, Very High and Severe susceptible zones on a raster map display, which is inevitably validated through statistical accuracy test by drawing a comparison with the 30% landslide inventory test dataset which exhibited 73% accuracy level. This landslide susceptibility map will invariably help the urban planners and the decision-makers in effective landslide risk mitigation and spatial design.