• Title/Summary/Keyword: 사토

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Erodibility evaluation of sandy soils for sheet erosion on steep slopes (급경사면의 면상침식에 대한 사질토양의 침식성 평가)

  • Shin, Seung Sook;Park, Sang Deog;Hwang, Yoonhee
    • Journal of Korea Water Resources Association
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    • v.55 no.4
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    • pp.291-300
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    • 2022
  • Artificial disturbance in mountainous areas increases the sensitivity to erosion by exposure of the subsoil with a low loam ratio to the surface. In this study, rainfall simulations were conducted to evaluate the erodibility of sand and loamy sand in the interrill erosion by the rainfall-induced sheet flow. The mean diameters of sand and loamy sand used in the experiment were 0.936 mm and 0.611 mm, respectively, and the organic matter content was 2.0% and 4.2%, respectively. In the experimental plot, the runoff coefficient of overland flow increased 1.16 times in loamy sand rather than sand. Mean sediment yields of loamy sand and sand by sheet erosion were 3.71kg/m2/hr and 1.13kg/m2/hr respectively. The erodibility, the rate of soil erosion for rainfall erosivity factor, was 3.65 times greater in loamy sand than in sand. As the gradient of the steep slope increased from 24° to 28°, the sediment concentration and the erodibility for two soils increased by about 20%. The erodibility factor K of sandy soils for small plots was overestimated compared to the measured erodibility. This means that RUSLE can overestimate the sediment yields by sheet erosion on sandy soils.