Transverse transport of suspended sediment across the main channel– floodplain shear boundary

[摘要] The floodplain of a river forms a close relationship with the stream that created it. Not only doesthe river influence the characteristics of the floodplain, the floodplain can also very easilyinfluence its river, as is evidenced by examples such as the Huang He River in China and theColumbia River in Canada. These two cases clearly indicate that suspended sediment has apronounced influence on the floodplain. This thesis investigates the processes which causesediment to move onto the floodplain.As observed in many rivers worldwide suspended sediment on the floodplain has a tendency tosettle near but not directly next to the main river channel. This gap between the river channel andthe location of highest sedimentation rate stems from the fact that there is a zone of relativelyhigher turbulence at the boundaries of the floodplain. Close to this zone flow on the floodplain isincreased in velocity whilst the flow velocity in the main channel is decreased as can be seen inthe figure below: ...

[发布机构] Stellenbosch University