AHP Model-based Mapping of Flood and Landslide Susceptibility in Bhagirathi Basin
Keywords:Analytical Hierarchy Process (AHP), Flood and Landslide Susceptibility, Natural Disasters, Socio-economic status
Analytical Hierarchy Process (AHP) prediction models are being used in the social and economic sciences to assess, locate, and address complicated socio-economic issues and get an output of complex interactions between various variables linked with ambient physical, socio-cultural, economic, and political systems. The current study focuses on the ' Bhagirathi Basin' of the central Himalayas, which is prone to landslides and flood disasters due to extreme rainfall and other environmental factors. The susceptibility assessment study used 10 parameters under five themes: climatic, topographical, hydrological, edaphic, and land-use patterns for assessing flood susceptibility and 14 parameters for landslide susceptibility. These distinct 16 parameters were analysed based on the AHP methodology that provides a rank of parameters and susceptibility map. For this study, CR values of 0.068 and 0.086, respectively, were calculated for flood and landslide susceptibility mapping to indicate the realistic level of consistency in the pairwise comparison study. The analysis found that 4.76% and 16.76% of the total area are associated with very high flood hazard zones. In comparison, 0.50%, 1.47% of the total area is associated with very high and high landslide hazard zones, followed by 19.61% with moderately high landslide hazard zones. The credibility of the present method was tested through validation with the previous landslide points and generated AUC value. The values close to (1) suggest high accuracy, whereas values close to (0.5) imply low accuracy. The AUC values reveal good agreement between the previous landslide points and the susceptibility map with a prediction accuracy of 84.4%. However, this study is helpful for the scientific community and researchers to understand the efficacy of the AHP model and the status of landslides and flood disasters.