Sediment Yield for Ungauged Watersheds in South Korea

摘要

Specific degradation (SD) is defined as the ratio of the sediment yield divided by the watershed area to compare sediment yield at the basin scale.The SD from 35 watersheds was calculated from field measurements of discharge and sediment concentrations.The watershed characteristics for each watershed were analyzed using GIS tools.All sediment gauging stations are located in alluvial river reaches and the estimated specific degradation typically ranges between 100 and 1,000 tons/knr-yr.Six regression models based on the watershed characteristics are proposed to estimate the mean annual sediment yield.The most useful relationship is function of the drainage area and mean annual precipitation.The proposed models were tested and validated with 15 additional river stations.The root mean square errors (RMSE) of the predictions are approximately 100 tons/km~2·yr which is found to be satisfactory.The proposed models should be useful to estimate the sediment yield from ungauged watershed in South Korea.