Estimating landslides vulnerability in Rwanda using analytic hierarchy process and geographic information system.

Autor: Li, Lanhai, Nahayo, Lamek, Mind'je, Richard, Nsengiyumva, Jean Baptiste, Ndayisaba, Felix, Karamage, Fidele, Mupenzi, Christophe, Kalisa, Egide
Předmět:
Zdroj: Integrated Environmental Assessment & Management; May2019, Vol. 15 Issue 3, p364-373, 10p
Abstrakt: Landslides are among hazards that undermine the social, economic, and environmental well‐being of the vulnerable community. Assessment of landslides vulnerability reveals the damages that could be recorded, estimates the severity of the impact, and increases the preparedness, response, recovery, and mitigation as well. This study aims to estimate landslides vulnerability for the western province of Rwanda. Field survey and secondary data sources identified 96 landslides used to prepare a landslides inventory map. Ten factors—altitude, slope angles, normalized difference vegetation index (NVDI), land use, distance to roads, soil texture, rainfall, lithology, population density, and possession rate of communication tools—were analyzed. The Analytical Hierarchy Process (AHP) model was used to weight and rank the vulnerability conditioning factors. Then the Weighted Linear Combination (WLC) in geographic information system (GIS) spatially estimated landslides vulnerability over the study area. The results indicated the altitude (19.7%), slope angles (16.1%), soil texture (14.3%), lithology (13.5%), and rainfall (12.2%) as the major vulnerability conditioning parameters. The produced landslides vulnerability map is divided into 5 classes: very low, low, moderate, high and very high. The proposed method is validated by using the relative landslides density index (R‐index) method, which revealed that 35.4%, 25%, and 23.9% of past landslides are observed within moderate, high, and very high vulnerability zones, respectively. The consistency of validation indicates good performance of the methodology used and the vulnerability map prepared. The results can be used by policy makers to recognize hazard vulnerability lessening and future planning needs. Integr Environ Assess Manag 2019;00:000–000. © 2019 SETAC Key Points: Disaster vulnerability increases mainly due to lack of timely risk information sharing and integrated vulnerability assessment, which would enhance the risk awareness and preparedness.The Analytic Hierarchy Process weighted the vulnerability causal factors, then the geographic information system helped to spatially distribute the vulnerability within the study area.The findings contribute to future strategic planning and mitigation strategies toward disaster risk reduction and sustainable development. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index