Analisis Tingkat Risiko Bencana Tanah Longsor Berbasis Sistem Informasi Geografis (Studi Kasus : Kecamatan Kutabuluh, Kabupaten Karo)

Abstract

Landslides are a common natural disaster in Indonesia, particularly in areas with steep topography and high rainfall, such as Kutabuluh District, Karo Regency. This study aims to analyze the level of landslide risk using a Geographic Information System (GIS) through regional vulnerability, susceptibility, and capacity. Vulnerability parameters include slope gradient, elevation, soil type, rock, rainfall, land use, and seismicity; while vulnerability occurs in population density and house value, and capacity are taken from BNPB and InaRISK data. The analysis was conducted using scoring, weighting, and overlay methods in QGIS 3.28.4. The results show five levels of risk: very low (10,628 km²), low (82,716 km²), moderate (107,384 km²), high (31,774 km²), and very high (1,706 km²). High risk is found in Kuta Buluh, Negeri Jahe, and Ujung Deleng Villages, while very high risk is found in Bintang Meriah Village. Validation using a ROC curve yielded an AUC of 0.934 (93.4%), indicating excellent accuracy. This risk map is expected to serve as a reference for disaster mitigation and sustainable spatial planning.