Author(s): Haruyuki Hashimoto; Hiroyuki Nagano
Linked Author(s):
Keywords: Sediment runoff; Reservoir sedimentation; Specific sediment deposition
Abstract: Sediment control over a whole river basin becomes important from the viewpoint of river environment and flood disaster. The sediment control needs an estimation of long-term and short-term runoff of sediment from a river basin. The purpose of the present study is to estimate a long-term sediment runoff from a river basin. Sediment runoff from a river basin occurs through several processes of sediment production caused by natural weathering and slope failure, and sediment erosion, transport and deposition caused by river and overland flow. Therefore, sediment runoff is governed by many factors, such as precipitation, geology, topography, land use, flow condition and so on. In the present study, reservoir sedimentation data is used for the analysis of sediment runoff. First, the relationship between specific sediment deposition and river basin area is discussed as parameters of prefecture region and geological condition. Second, a hydraulic consideration of the bed-load transport equation yields a linear relationship between annual sediment discharge and annual river flow discharge. Finally a simple formula is proposed to estimate annual runoff of sediments from a river basin.
Year: 2010