APLIKASI SISTEM INFORMASI GEOGRAFIS DALAM MEMPREDIKSI EROSI DENGAN METODE USLE DI SUB DAS DUMOGA

Abstract

Abstract
The objective this study was to predict erosion rate and erosion hazard level in Dumoga
Sub-watershed. The study is expected to provide spatial information on erosion rate
and erosion hazard level in Dumoga Sub-watershed, particularly for spatial planning as well
as soil and water conservation. Erosion was predicted employing USLE while spatial analysis
was conducted using Geographic Information Systems (ArcView 3.3). Rainfall data were collected
from three weather stations, erodibility values obtained by analyzing samples from
three soil types, slope categories were determined using DEM (Digital Elevation Model), values
of the landuse and soil conservation were determined by means of satellite image interpretation
in and field survey as well. It was found that soil erosion ranged from 0.39 to
16.800 tonnes /ha/year. The lowest erosion rate occurred on forest land and ricefield withhacing
flatslope. The highest erosion rate was identified on farm land having very steep slope.
Erosion hazard level varied from verylow to very severe. It is necessary to perform soil and
water conservation measured on the land experiencing severe to very severe erosion hazard
as to reduce soil erosion.
Keywords: Erosion, Geographic Information System, Watersheed