Multi Hazard Risk Assessment Using GIS Techniques in the Mbo Area of Nigeria
Okpo O. Ekere
Department of Geography and Regional Planning Faculty of Social Sciences, University of Uyo, Uyo, Nigeria
Joseph C. Udoh
Department of Geography and Regional Planning Faculty of Social Sciences, University of Uyo, Uyo, Nigeria
Keywords: Hazard, Vulnerability, Risk assessment, GIS, AkwaIbom State.
Abstract
The study area Mbo and environs of South Eastern Nigeria are experiencing frequent inundation by flood and erosion hence this research is aimed at generating vulnerability hazard and risk maps as decision support tools for policy makers. Rainfall, elevation, slope, soil association and hydrology were used as input layers to model the hazard layers while population density, vegetation and Normalized Difference Vegetation Index (NDVI) were used to model the vulnerability layers. Risk maps were generated weighting and combining the Hazard and vulnerability layers using the Single Output Map Algebra function of Arcmap soft ware. The final multi hazard risk map , derived by combining the flood and erosion risk maps shoed that 119.62km2 (15.12%), 193.94km2 (24.52%), 292.33km2 (36.95%) and 185.20km2 (23.41%). The study, using GIS, has revealed an objective way of understanding and dealing with the impact of hazards in the study area.