Analysis of erosion hazardous level and sedimentation in Manna Watershed, Bengkulu Province Indonesia

Abstract

The research purposeis to analyze erosion hazardous level and sedimentation on Manna watershed, Bengkulu Province. The research area geographically lies between 102°51′38.2″-103°10′57.8″ East., and 4°0′39.6″-4°29′38.0″ South covering 72,071.9 ha. Potential erosion yield and level were calculated by applying Universal Soil Loss Equation, and spatial analysis of the erosion was done using ArcGIS. The potential erosion in Manna watershed was classified as moderate hazardous level of 12,442,368.12tons yr-1 or similar to170.68 tons ha-1yr-1. Moderate to high level Soil erosion covered areas of 47,359.00ha, or 65.19% of Manna watershed, and high risk of potential erosion with very high sedimentation rate amounted to 248.851,1 tons yr-1. In short, land cover in Manna watershed was generally in high environmental pressures, therefore, and in future, water resources would face environmental problems.