Field and Laboratory Investigations on the Effects of Riparian Vegetation on Stream Flow and Sediment Dynamics

摘要

The use of vegetation for the restoration of degraded streams is widespread. However thorough testing of the effects of an actual restoration project on flow and sediment dynamics in a natural stream has not been conducted. Thus field and laboratory model investigations were commenced to examine the effects of revegetation on a degraded sand bed stream. Field and laboratory experiments were linked by the similitude of topography, hydraulic roughness and shield's regime. Significant effects on bed shear stress, centrifugal forces and turbulence were evident. Bank vegetation caused an increase in bedload transport over the opposite bank, and increased suspended sediment concentration near the vegetated bank. The results of this investigation both extend and confirm the findings of other laboratory experiments. Future work is aiming to reproduce the main effects in a simple numerical model.