Mapping of Landslide Susceptibility Using State-of-the-Art Method and Geospatial Techniques in the Rangamati District in the Chattogram Hill Tracts Region of Bangladesh

The chapter aims to map the susceptibility of landslides in the Rangamati district of the Chattogram Hill Tracts region in Bangladesh using state-of-the-art methods and geospatial techniques. The district has experienced a significant number of landslides that caused numerous fatalities. However, the lack of available data and proper synchronization of existing information impedes our understanding of the extent of the issue. An integrated approach combining community-based mapping, Participatory Rural Appraisal (PRA) techniques, and spatial analysis was employed to address this challenge. Generation of landslide inventory revealed 306 landslide locations spread across the entire district, with 54.58% located in Rangamati Sadar upazila. Additionally, spatial statistical analysis was conducted to find the association of landslides with 12 causative factors. Analysis revealed that areas with Boka Bill geological formation had 37.91% landslide locations, making this region highly susceptible. Similarly, areas with elevations within 50–200 m and slopes of 10°–20° have recorded the highest number of landslides in the study area, with 40.85% and 50.33% of landslide locations, respectively. The study's findings also indicated that areas close to roads (0–250) m and settlements (0–25) m had the highest number of landslide locations, 61.76%, and 34.64%, respectively. Overall, findings indicated that around 43.58 km2 area of Rangamati district are susceptible to landslides. This chapter offers a comprehensive understanding of landslide susceptibility using an integrated geospatial approach. The findings will lay the foundation for developing a landslide vulnerability model to enhance landslide risk assessment and facilitate effective mitigation measures in the future.