Dynamics of the turbidity maxima in the upper Humber estuary system, UK

Turbidity maxima in estuaries are important due to their influence on prima ry production, pollutant flushing, fish migration and dredging, There is a need for a better understanding of the dynamics of turbidity maxima. Result s are given for the response of turbidity maxima and salinity in the tidal Trent and (Yorkshire) Ouse over time scales of a semidiurnal tide to an ann ual cycle with respect to tidal and fluvial influences. Under low fresh wat er flow conditions sediment moves landward and the turbidity maximum is obs erved upstream of the fresh-salt water interface. Longitudinal dispersion p rocesses governing salinity appear to be dominated by transverse shear indu ced effects. Suspended solids concentrations within the turbidity maximum a re strongly influenced by tidal asymmetry and suspended solids vertical con centration gradient effects and their associated influences, It is proposed that the higher concentrations of suspended solids in the Ouse estuary, co mpared with the tidal Trent, are due to the influence of the lower fluvial discharge in the appropriate reaches. (C) 1999 Elsevier Science Ltd. All ri ghts reserved.