Composition of estuarine macro-aggregates and their importance as concentration sites for micro-organisms in the Schelde estuary (Belgium)
Fockedey, N. (2005). Composition of estuarine macro-aggregates and their importance as concentration sites for micro-organisms in the Schelde estuary (Belgium), in: Fockedey, N. Dieet en groei van Neomysis integer (Leach, 1814) (Crustacea, Mysidacea) = Diet and growth of Neomysis integer (Leach, 1814) (Crustacea, Mysidacea). pp. 189-199 In: Fockedey, N. (2005). Dieet en groei van Neomysis integer (Leach, 1814) (Crustacea, Mysidacea) = Diet and growth of Neomysis integer (Leach, 1814) (Crustacea, Mysidacea). PhD Thesis. Universiteit Gent. Vakgroep Biologie, sectie Mariene Biologie: Gent. X, 297 pp., more |
| Keywords | Microorganisms
Microorganisms > Bacteria
Resources > Natural resources > Mineral resources > Mineral deposits > Seabed deposits > Aggregates
Water bodies > Coastal waters > Coastal landforms > Coastal inlets > Estuaries
Belgium, Zeeschelde [Marine Regions]
Marine/Coastal |
| Abstract | In November 1997 and June 1998, the composition of estuarine macro-aggregates in the Schelde estuary was investigated at 4 sites situated in the estuarine turbidity maximum. The flocculation process was simulated in vitro using rolling cylinders and macro-aggregates were separated from the surrounding water by sedimentation and decantation. 47 - 90 % of the suspended particulate matter, 29 - 67 % of the particulate organic carbon, 6 - 57 % of the chlorophyll a, 1 - 39 % of the bacteria, 5 - 14 % of the heterotrophic nanoflagellates and 5 - 25% of the ciliates in the water column were found to occur in association with the macro-aggregates. The fraction of total chlorophyll a that was associated with the macro-aggregates was at all sites lower in June when compared to November. The fraction of total bacteria that was associated with the macro-aggregates was highest in the freshwater tidal reaches and tended to decrease in downstream direction. Concentrations of bacteria, heterotrophic nanoflagellates and ciliates in the macro-aggregates were generally one to two orders of magnitude higher than in the surrounding water. Despite high concentrations of micro-organisms in the macro-aggregates, living biomass contributed at most to 3.2 % of total organic carbon of the macro-aggregates. |
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