A cohesive sediment balance for the Scheldt estuary
van Maldegem, D.C.; Mulder, H.P.J.; Langerak, A. (1993). A cohesive sediment balance for the Scheldt estuary. Neth. J. Aquat. Ecol. 27(2-4): 247-256. https://dx.doi.org/10.1007/BF02334788 In: Netherlands Journal of Aquatic Ecology. Kluwer Academic Publishers/Netherlands Society of Aquatic Ecology: Bilthoven. ISSN 1380-8427; e-ISSN 2214-7098, more Also appears in:Meire, P.; Vincx, M. (Ed.) (1993). Marine and estuarine gradients: ECSA 21: Proceedings of the 21st symposium of the Estuarine and Coastal Sciences Association held in Gent, 9-14 september 1991. Netherlands Journal of Aquatic Ecology, 27(2-4). Netherlands Society of Aquatic Ecology: Bilthoven. 496 pp., more | |
Keywords | Marine/Coastal; Brackish water | Author keywords | mud balance; mud transport; fluvial mud; marine mud; sediment transport; sediment balance; Scheldt estuary; management |
Authors | | Top | - van Maldegem, D.C., more
- Mulder, H.P.J., more
- Langerak, A.
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Abstract | This article presents a method to generate a cohesive sediment balance for the Scheldt estuary (The Netherlands and Belgium). In this balance the net transports have been determined on a regional scale. The complicated circulation patterns on a smaller scale are considered as a black box. The cohesive sediments in the balance are defined as the inorganic sediment with a particle size smaller than 63 um. In the balance a distinction is made between the relatively 'clean' marine mud fraction and the more polluted fluvial fraction. The calculations are made on a basis of field data. The field data of the morphological changes in the estuary are based on the period of 1975-1985. The net natural transport of fluvial mud is estimated to reach beyond the mouth of the estuary. The net marine import of mud is estimated to reach beyond the brackish part of the estuary, located in Belgium. The sediment balance also provides the time scale for the response of an estuary. The time scale related to the reduction in pollution proves to be quite large. Calculations with a simple analytic model with typical values for the Scheldt estuary indicate that several decades will pass until a significant improvement in bottom sediment quality is reached even after a 100% reduction of the loading of pollutants. The presented balance is not the final answer. Improvements can be achieved by more accurate field data, smaller morphological units and verification by other methods (cf. tracer methods, mathematical models). |
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