Susceptibility Mapping of Rainfall Induced Landslides Using Weight of Evidence Method in Jumre Khola Watershed of Pyuthan District, Nepal

Abstract

The world’s development infrastructure is at risk from landslides and their consequences in many areas across the globe. There is evidence that landslide disaster is increasing in developing countries. Lesser Himalaya of Nepal is highly susceptible for landslide and various people lose their life and property each year due to landslide. The main aim of this study was to prepare 1) to identify the specific characteristics of landslides in Jumre Khola watershed. 2) To relate the rainfall intensity with landslides distribution in Jumre Khola watershed. & 3) To prepare landslide susceptibility map of Jumre Khola watershed. For this, a detailed landslide inventory was prepared by field survey and Google Earth imagery interpretation. This inventory map was separated into two groups for training the model and validating the result. A landslide susceptibility maps was developed by WOE model. Finally, validation of the model was done by using the success rate curve analysis. The verification result showed that the model performed very well with the success rate of 86.79%. The generalized linear model was performed between landslide and rainfall to know if there is significant relationship between landslide and rainfall. The Jumre Khola watershed is selected for the present study due to the presence of a large number of landslides in the region as well as due to the presence of huge amount of settlement in the mountain slopes and the river valley that are in high risk of landslides. The produced susceptibility map can be useful for general land-use planning, as well as it can provide information to the planners for the adaptation of appropriate mitigating measures for landside in the Jumre Khola watershed.