Sistem Infomasi Geografis (Sig) untuk Analisa Kerawanan Longsor Berdasarkan Faktor Alam ( Studi Kasus : Kabupaten Nias Utara )

Abstract

Landslide is an event where material on the slopes moves in the form of soil, rock and other organic material due to the influence of gravity, resulting in a change in the shape of the land. North Nias Regency is an area prone to landslides due to its hilly and undulating topography. To be able to identify the level of landslide vulnerability and the distribution of landslide-prone areas in North Nias Regency, the researchers utilized mapping technology with a Geographic Information System (GIS) and satellite imagery. In this final project, the researcher uses reference to the Regulation of the Minister of Public Works No.22/PRT/M/2007 regarding areas prone to landslides. The indicators used are slope, rock type, soil type, rainfall, seismicity, slope water system, and vegetation. Each indicator is given a score and then multiplied by the weight percentage and then summed based on the suitability of its geographical location. From the analysis of the landslide vulnerability map in North Nias District, there are 3 vulnerabilities, namely low, medium and high. Based on the dominance of the level of landslide vulnerability in each sub-district, it was found that almost all sub-districts were dominated by a medium level of landslide vulnerability, covering an area of 1063,021 km2 of the area of North Nias Island, namely 1242.14 km2 or 85.57% of the area of North Nias Regency.