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Title: Stratification in the Severn Estuary- Physical aspects and biological consequences
Author: C.S. Reynolds
Author: J.R. West
Document Type: Monograph
This report focuses on stratification in the Severn Estuary. Vertical stratification in estuaries may be induced by vertical gradients of salinity, temperature and suspended solids. The hydrodynamic effect of vertical stratification is to inhibit the vertical transport of momentum, solutes and particulate matter. The biological consequences of a reduction of vertical mixing are complex, but a basic important effect is the reduction in mineral suspended solids concentration leading to clearer water and hence an increase in primary productivity. A review of existing salinity and suspended solids concentration data shows that under present summer spring tide conditions the estuary shows periods of stratification particularly in the region of the times of high and low slack waters. During neap tides stratification is stronger and lasts for longer periods, particularly on the ebb tide. The stratification is in the form of continuous density profiles rather than in the form of two separate layers commonly found in lakes and fjords.
Publisher: Freshwater Biological Association
Publication Date: 1988
Publication Place: Ambleside
Subject Keywords: Estuaries; Stratification; Suspended solidsHydrodynamicsTidesSalinityTurbidityBiological processesPhytoplanktonAlgae
Geographic Keywords: Severn Estuary
Extent: 32; + tables and figures
Total file downloads: 184

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