The quasi-equilibrium assumption 7, also adopted by Van Leussen (1994), Winterwerp et al. (2006) and MD07, permits a considerable simplification of the formulation of ws and MSF. This ignores any time lag between a change in the flow speed and the response of the floc size and structure: e.g., Verney et al. (2010) showed in laboratory tidal simulations that nitric oxide synthase the floc response could exhibit a lag of more than 20 min during floc aggregation, but was almost instantaneous during floc break-up. In most tidal estuary situations assumption 7 is a good approximation. However, it might underestimate the initial deposition rate in cases where the flow velocity decreases abruptly (e.g. ingress of turbulent sediment-laden water into a quiescent harbour) because the predicted settling velocity decreases abruptly instead of slowly, and, vice versa, overestimate it where the velocity increases abruptly (e.g. under a tidal bore).
3.2. Turbulent energy dissipation
equation(1)
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