Landslide spatial distribution and its accurate detection are vital in hazard, vulnerability, and risk disaster management and mapping. The study aims to develop landslide risk zonation maps using integrated remote sensing and GIS technology in the Ghat Road Section of the High Wavy Mountains of Megamalai, Tamil Nadu, India. In the present study, 25 landslide points were located over the examined area, including historical destructive geological events and field investigations. The present research consists of three phases of mapping: Landslide Hazard Zonation (LHZ), Landslide Vulnerability Zonation (LVZ), and Landslide Risk Zonation (LRZ). The LHZ map was developed using nine primary landslide-influencing parameters: elevation (E), slope (SL), aspect (As), drainage density (DD), distance to river (DR), distance from road (Dr), yearly rainfall (R), geology (G), and soil (S). The LVZ map was developed using six primary landslide-contributing parameters: land use and land cover (LULC), geomor-phology (Gm), distance from faults (Df), topographic wetness index (TWI), plan curvature (Pl), and normalized difference vegetation index (NDVI). The Analytical Hierarchy Process (AHP) method was used to integrate the thematic maps. The final result of the present study is the landslide risk zonation (LRZ) map, which is a combination of the LHZ and LVZ. The risk of landslides is depicted on a map that shows five levels of risk, ranging from Very High Hazard (8.15%), High Hazard (18.71%), Moderate Hazard (26.86%), Low Hazard (25.38%), and Very Low Hazard (19.82%). The results revealed that 30% of the study area falls under very high- to high-risk zones, which represents an alarming stage of landslide activity. Based on risk management, the study area was further analyzed for the sustainability status of the landslide. The output of the research is very useful for planners, highway authorities, and engineers for developing a landslide early warning system.
Kirithika et al. (Tue,) studied this question.