Pemetaan Tingkat Bahaya Erosi Berbasis Sistem Informasi Geografis (SIG) (Studi Kasus : DAS Duriangkang, Kota Batam)

Abstract

Soil erosion is one of the land degradation issues that can damage the environment and affect the quantity and quality of water in watersheds. The Duriangkang Watershed in Batam City plays a vital role as a water catchment area that supplies raw water to the Duriangkang Reservoir; therefore, information on erosion risk levels is essential to support sustainable watershed management. The objective of this study is to calculate erosion rates and map erosion risk levels in the Duriangkang Watershed by applying the Revised Universal Soil Loss Equation (RUSLE) method using a Geographic Information System (GIS). The analysis was conducted using five main parameters: rainfall erosivity factor (R), soil erodibility (K), slope length and slope gradient (LS), land cover factor (C), and conservation practices (P). The R factor value was obtained using the Lenvain equation based on rainfall data for the 2016–2025 period, while the K, LS, and CP factors were calculated through spatial data processing using ArcGIS software. Accuracy tests of the land cover map showed an Overall Accuracy of 91.30% and a Kappa Accuracy of 89.35%, indicating that this map is sufficiently accurate and suitable for use as input data in RUSLE analysis. This study produced a map showing the distribution of erosion hazard levels, highlighting variations in erosion potential within the Duriangkang Watershed, which can serve as a basis for developing soil conservation strategies and sustainable watershed management.