An ecological perspective on estuarine classification
Jay, D.A.; Geyer, W.R.; Montgomery, D.R. (2000). An ecological perspective on estuarine classification, in: Hobbie, J.E. (Ed.) Estuarine science: a synthetic approach to research and practice. pp. 149-176 In: Hobbie, J.E. (Ed.) (2000). Estuarine science: A synthetic approach to research and practice. Island Press: Washington D.C.ISBN 1-55963-700-5. XI, 539 pp., more |
| Authors | | Top | - Jay, D.A.
- Geyer, W.R.
- Montgomery, D.R.
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| Abstract | Estuaries are more numerous and diverse than any other type of marine environment. Scientists and managers currently face a range of issues associated with global alteration of estuarine systems without a thorough understanding of how such changes affect either estuaries or the larger coastal global oceans to which they are connected. Exhaustive study of all highly altered systems is impractical. It is necessary instead to analyze representative systems characteristic of the spectrum of estuarine types. Identification of representative estuaries requires development of a classification scheme that connects physical processes (circulation and sediment to transport) to biogeochemistry and ecology in a predictive manner. Traditional classification efforts focused almost exclusively on the influences of tidal forcing and river inflow on circulation in narrow estuaries. To be useful over the range of estuarine types, a process-based geomorphic classification should include other types of physical forcing; that is, the effects of wind, wind waves, sea ice, and surface heating and cooling. Fluid mechanics and geomorphology can be connected through description of forcing variables for sediment movement in estuaries in terms of hydrodynamic parameters. One important parameter is residence time (TR). TR strongly influences larval recruitment and biogeochemical and ecology processes vital to the lower levels of the estuarine food chain. It is a major habitat parameter for higher trophic levels. Knowledge of a mean TR is, moreover, not sufficient; its temporal variability and spatial heterogeneity should be considered. Finally, we suggest a hypothesis concerning estuarine particle retention processes that, if correct, should allow prediction of residence time and trapping efficiency for at least some estuarine types in the near future. |
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