Soil Erosion Reduction Plan for Watershed with Sloping Fields of Highland Agriculture by Using GEOWEPP Model

Abstract

This study was performed to suggest a soil loss reduction skill through estimating soil erosion from a small watershed including each type of sloping agriland by using GEOWEPP model. Experimental watershed at Gangwon province was selected for very typical sloping fields of highland agriculture in Alpine area. Runoff discharge and sediment load, hourly rainfall amount occurred during storm event were gauged, and weather data were obtained from Daegwallyeong meteorological station. The results of GEOWEPP model estimation showed that relative error values for total runoff discharge and sediment load were 3 %, -14.5 % respectively. Based on the result, soil erosion and waterway path map for each hillslope were made to select target hillslope. Several hillslopes of severe soil erosion were analyezed and then the optimal vegetative filter strip construction width and waterway path to plant grass were decided by using GEOWEPP Model.

SEMMA Revision to Evaluate Soil Erosion on Mountainous Watershed of Large Scale

“…물리기반의 수문학적 토양 침식 모형인 WEPP(Water Erosion Prediction Project)은 경작지, 방목지, 그리고 산림지의 소규모 사면부터 중규모 유역에 이르기까지 토양침식과 토사유출량 모의가 가능하 다 (Flanagan and Nearing, 1995). Renschler(2003)는 GIS 상에서 공간분석이 가능한 GeoWEPP을 제시하였으며, 이모형은 국내 유역의 유출 및 토사유출 평가에 활용되고 있다 (Lee, 2007;Moon et al, 2010;Choi et al, 2011). Kim et al (2007)은 소유역에 대한 토사유출량을 평가한 결과 GeoWEPP이 USLE보다 관측 값에 근사하게 모의함을 확 인하였다.…”