Effects of Fine Sediment Resuspension in Estuaries

Abstract

Sediments supplied to an estuary undergo repeated cycles of resuspension and deposition prior to permanent accumulation or transport into the sea. A review of published literature and field observations of estuarine suspended sediment in the Chesapeake Bay region, indicate that sediment is resuspended in response to fluctuating energy over a wide range of time scales. The temporal variations of resuspension, therefore, inherit a hierarchy of scales following the scales of motion.Resuspension is a key process in the cycling of fine sediment in estuaries. The process enriches the suspended sediment load and stratifies the vertical gradients of suspensions. It increases the mean residence time of suspended sediment in the water column. Therefore, resuspension reinforces horizontal advective transport and enhances the turbidity maximum. Resuspension modifies the chemical composition of estuarine sediments by increasing the interaction time, sequestering or releasing chemicals and by mixing sediment from different sources, or from the same source but with a different geochemical history.KeywordsCurrent VelocityFine SedimentTidal CycleSuspended Sediment ConcentrationCritical Shear StressThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.