Cohesive Sediment Dynamics on an Inter-tidal Bank on the Tidal Trent, UK

摘要

This paper uses Photo-Electronic Erosion Pin (PEEP) data and measurements of sediment dynamics on an active inter-tidal bank to determine the significance of changes in tidal range, sediment availability and meteorological conditions on sediment accretion and erosion. The results show how sediment accumulates on the upper bank at a rate of up to 50 mm per tide in response to increased suspended sediment concentrations during spring tides. However, sedimentary processes differ on the lower bank as deposition occurs approaching spring tides, only to be eroded by high boundary shear stresses generated by the flow as tidal range increases to a maximum. Erosion from the upper bank appears to be dominated by wind-induced wave activity which destabilises the transient, active sediment layer. These results have implications for evaluating the behaviour and residence times of sediment and pollutants within the estuarine system, the impact of the turbidity maximum on the recirculation of sedimentary deposits, and the significance of wave activity on erosion processes in inter-tidal zones.