Modeling vulnerability density of landslide using IFSAR DEM in Manuju and Bungaya District Gowa Regency, South Sulawesi

Abstract

Recently in Indonesia landslide is one of major natural disaster that claims lives and property. Therefore it is necessary to have a Landslide Vulnerability Zone Map to improve the accuracy of natural disaster risk analysis and mitigation needs by using IFSAR DEM. Generally, Gowa area contains with moderate to strong undulating topography is very often created landslide issue. Parameters are used to analyze the landslide zoning are lithology, slope, slope aspects, distance from faults, distance from river, distance from road, land cover, slope length, rainfall, soil type, and curvature. Each parameter map and landslide map were integrated to compute the value of density and landslide occurrence percent obtained in different units from each of the maps. Determination by using all parameters above showing accuracy value of 89,4% where 85% area on past landslides occurred on very high hazard zone and 12.92% occurred on high hazard zone, meanwhile selected parameter accuracy value is 98,5% where 85% area on past landslide event occurred on very high hazard zone while 12.92% occurred on high hazard zone. Parameter selection can improve the accuracy of landslide zoning on the research area.