Landslide Susceptibility Mapping using Frequency Ratio, a case study of Vythiriblock in Wayanad, the northern part of Kerala, India

Landslides are common and disastrous events in India's Western Ghats during the rainy season and various factors influence the occurrence of landslides. The present research aims to establish landslide susceptibility zones to control landslide hazards and risk effectively. Landslides occurred in the entire area of the Wayanad district. The study was carried out in vythiri taluk to do detailed surveys using remote sensing and GIS, GPS and field investigation. A total of 162 landslide locations are used to develop a landslide susceptibility map of this area. Landslide susceptibility map of this area was done by using the frequency ratio (FR) model. The landslide susceptibility map is based on factors that affect directly or indirectly land subsidence process. There are twelve landslide influencing factors taken for this study: Slope, Aspect, Land use/land cover, Rainfall, Vegetation, Soil, Distance to lineament, Distance to the road, Elevation, Curvature, Geomorphology and Lithology. The resulting landslide susceptibility map shows that 3.6 % of the region is in a low susceptible zone, 40.5 % is in a moderate susceptible zone, 49 % is in a high susceptible zone and 6.9 % is in a very high susceptible zone to landslides. According to this model, the area under the curve (AUC) for the success rate is 75.3 %. This study would support the relevant authorities in identifying potential risks in particular parts which could be used for landslide mitigation activities as construction development in the region increases.