Pendugaan Erosi dan Perancangan Teknik Konservasi Tanah dan Air sebagai Upaya Mitigasi Erosi di DAS Wampu

Abstract

Estimation of erosion in the Watershed (DAS) is very important to be done for better watershed management. High levels of erosion can determine the condition of a land. High erosion can cause a decrease in the effectiveness of land use to environmental damage such as landslides due to erosion of the topsoil so that the soil's ability to retain and absorb water is reduced. Wampu Watershed is one of the watersheds in North Sumatra Province which is classified as vulnerable to erosion and there have been few studies on erosion in Wampu Watershed. This study aims to estimate erosion and design soil and water conservation techniques that are in accordance with the conditions in Wampu Watershed. This study uses the Universal Soil Loss Equation (USLE) method with factors that affect the amount of erosion such as rainfall erosivity (R), soil erodibility (K), slope gradient (LS) and land cover and land management (CP). The results of the study showed that the very light erosion hazard class covering an area of 203,310 Ha was the largest erosion class in the Wampu Watershed, followed by light erosion covering an area of 149,242.00 Ha, then moderate erosion covering an area of 45,814.02 Ha, then severe erosion covering an area of 14,412.90 Ha and very severe erosion covering an area of 2,794.30 Ha. The upstream part of the Wampu Watershed, especially in Karo Regency, is the area with the widest very heavy erosion level. Soil and water conservation design is the initial step to prevent erosion in the Wampu Watershed. Soil and water conservation techniques in open land can be implemented by planting ground cover plants, replanting woody plants or planting herbal plants that have ecological and economic functions.