LANDSLIDE SUSCEPTIBILITY MAPPING OF SOUTH-EASTERN RANGAMATI DISTRICT, BANGLADESH

Recent change of climate mainly temperature and rainfall patterns has significantly increased the rainfall induced landslide hazards in the south eastern folded part of Bangladesh including Rangamati district. Thousands of families become homeless each year due to this disaster. Hill cutting for urban development and settlement at the bottom hills has significantly increased the risk of landslides in the Rangamati area.

In this research, an attempt has been made to prepare the Landslide susceptibility map for the Rangamati Sadar area, parts of south eastern hill tracts of Bangladesh to identify the future susceptible areas of landslide occurrence. For this purposes, the study area targeted where rainfall induced landslides apparently causes causalities as well as property damage in the past. The landslide inventory map is prepared using the Google Earth images from 2017 with the field identification and verification. Landslide triggering factors such as geology, land use, DEM, slope, aspect, plan curvature, drainage distance, and road to distance, river density and structure datafrom open source spatial attributes are taken into consideration to prepare the susceptibility map.

Based on the overall observations, it is established that the investigated area can be classified into five different classes based on the degree of landslide susceptibility. They are viz. very low, low, medium, high and very highly susceptible areas. The susceptibility map has been validated with the field data. This established susceptibility map and data will help the stake-holders, policy makers & city dwellers for future sustainable landslide hazard and slope management related with future disaster risk reduction and mitigation activities & future urban planning of the city.