Multi-Criteria Landslide Susceptibility Assessment in a Tropical Volcanic Environment: An Integrated GIS–AHP and Geotechnical Approach from the Cameroon Volcanic Line

Abstract

Landslides are complex geomorphological hazards driven by multiple interacting geological, hydrological, and environmental factors, and they cause significant socio-economic and environmental impacts. Therefore, landslide susceptibility mapping is essential for effective hazard assessment and risk management. This study assesses landslide susceptibility along the Cameroon Volcanic Line, characterized by steep terrain, intense rainfall, and active tectonics. Remote sensing data, geotechnical investigations, and Geographic Information Systems (GIS) were integrated using the Analytic Hierarchy Process (AHP) to identify and map areas prone to slope instability. The analysis considered rainfall, soil characteristics, morphology, surface lineament density, deep lineament density, weathering thickness, drainage density, and vegetation cover. Geotechnical investigations revealed the presence of silty clay soils that may contribute to slope instability under high moisture conditions. The results indicate that rainfall is the dominant controlling factor, followed by soil properties, topography, and drainage density, whereas vegetation cover and fracture density exert a comparatively lower influence. The resulting susceptibility map highlights high-risk zones that are consistent with previously reported landslide occurrences. These findings demonstrate that integrating remote sensing, GIS, and geotechnical data within an AHP framework provides a reliable approach for landslide susceptibility assessment and risk management in tropical volcanic environments.