Analisis Daerah Rawan Tanah Longsor Berbasis Sistem Informasi Geografis (SIG) (Studi Kasus: Kecamatan Berastagi, Kabupaten Karo)

Abstract

Landslides are one of the natural disasters that cause many casualties and property. Landslides in Indonesia are becoming more frequent every year. This is due to the tectonic conditions of Indonesia and also the wet tropical climate forming high morphologies, faults, and volcanic rocks that are easily fragile in several regions of Indonesia. Berastagi District is one of the sub-districts in Karo Regency which is a landslide-prone area, so it is necessary to map the risk of landslides using GIS in a preventive effort to overcome and minimize the risks caused. This research refers to the Minister of Public Works Regulation No. 22/PRT/M/2007 for the preparation of landslide vulnerability maps and PERKA BNBP No. 02 of 2012 for the preparation of vulnerability maps and capacity maps. The data processing uses the QGIS 3.28.4 application with an overlay method between parameters with scoring and weighting methods, resulting in a landslide risk level which is then validated with the ROC curve. Based on the results of the analysis, the risk level of landslides in Berastagi District consists of 5 classes, namely the very low risk level class of 1,678 km2 (5.79%), the low risk level class of 11,482 km2 (39.59%), the medium risk level class of 4,394 km2 (15.15%), the high risk level class of 10,571 km2 (36.45%), and the very high risk level class of 0.876 km2 (3.02%). Berastagi District is dominated by a low risk level with a total of 3 sub-districts/villages, namely Gurusinga Village, Raya Village, and Rumah Berastagi Village.