Landslide’s analysis and Hazard mapping based on ANALYTIC HIERARCHY PROCESS (AHP) using GIS, in Lawas, Sabah-Sarawak

Abstract

This research was conducted to establish a landslides hazard map in a district called Lawas in Malaysia’s Sabah–Sarawak region using the AHP (Analytic Hierarchy Process) methods. Several landslides conditioning factors in the area were identified and used to build the AHP matrix. The landslides triggering factor(s) of the area was observed to be rainfall based on previous investigation reports for landslides in the regions and the landslides history records. The weightage values for the conditioning factors were assigned considering the contributions of each factor as observed from the spatial data analysis. These landslides’ conditioning factors were; slope, aspect, soil type, SPI, STI, rainfall intensity, elevation, Profile curvatures, and lithology. Satellite images constituted the primary part of the database used for the AHP analysis. GIS tools such as ArcMap were also utilized to read and analyze the remotely sensed data for the analysis. The susceptibility or hazard map was finally developed using ArcMap software through weighted overlay in a GIS (Geographic Information System) platform. The hazards map was later formulated by reclassifying the landslides susceptibility maps. Overall, the study revealed that all factors collected were very influential to landslides occurrence in the study area and that the AHP method was also discovered to be effective.