Landslide Susceptibility Assessment Using Spatial Multi-Criteria Evaluation Model in Rwanda.

Area of Science:

• Geosciences
• Environmental Science
• Disaster Management

Background:

• Landslides pose a significant threat in Rwanda, necessitating detailed susceptibility assessments.
• Effective risk management requires precise identification of areas prone to landslides.

Purpose of the Study:

• To conduct a landslide susceptibility assessment in Rwanda using a Spatial Multi-Criteria Evaluation Model.
• To identify and map regions with varying degrees of landslide susceptibility across the country.

Main Methods:

• Applied a Spatial Multi-Criteria Evaluation Model incorporating eight causal factors: slope, distance to roads, lithology, precipitation, soil texture, soil depth, altitude, and land cover.
• Utilized a dataset of 980 past landslide locations to calibrate and validate the model.
• Analyzed the spatial distribution of landslide susceptibility and its correlation with population density.

Main Results:

• Over 42% of Rwanda exhibits moderate to very high landslide susceptibility, affecting nearly half of the population.
• Western, Northern, and Southern provinces show the highest susceptibility levels.
• The Eastern Province is predominantly characterized by low susceptibility, with no very high susceptibility zones identified.

Conclusions:

• The Spatial Multi-Criteria Evaluation Model accurately identified landslide-prone areas, with 49.5% of past landslides occurring in very high susceptibility zones.
• The findings provide crucial data for developing targeted landslide risk reduction and management strategies in Rwanda.
• The study highlights the importance of integrating multiple causal factors for reliable landslide susceptibility mapping.