Measurements of flow, turbulence and suspended sediment concentration wererncarried out in a tidal creek that acts as a conduit for water and sediment to an intertidal saltrnmarsh. A laser system (LISST) was used to measure particle size variability in the population ofrnsediment in suspension. Results suggest that floculation is an important parameter controllingrnadvection, which in turn influences sediment transport and marsh accumulation. Flocs break atrnhigh flow conditions of spring tides enhancing the importance of sediment advection. Duringrnneap tides turbulence levels are lower and contribute to the formation of flocs. The higherrnsettling velocity of flocs contribute to early settling of the particles and reduced advection. Arnsimplified model of sediment transport due to tidal forcing alone was used to examine sedimentrntransport during spring and neap conditions. The measured tidal characteristics of flow,rnestimated drag coefficients and settling velocities were used to drive the model. The resultsrnindicate that salt marsh sediment import occurs primarily during spring tides.
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