Changes in phytoplankton biomass and primary production between 1991 and 2001 in the Westerschelde estuary (Belgium/The Netherlands)
Kromkamp, J.C.; Peene, J. (2005). Changes in phytoplankton biomass and primary production between 1991 and 2001 in the Westerschelde estuary (Belgium/The Netherlands). Hydrobiologia 540(1-3): 117-126. https://dx.doi.org/10.1007/s10750-004-7124-9
In: Hydrobiologia. Springer: The Hague. ISSN 0018-8158; e-ISSN 1573-5117, meer
Ook verschenen in:Meire, P.; Van Damme, S. (Ed.) (2005). Ecological structures and functions in the Scheldt Estuary: from past to future. Hydrobiologia, 540(1-3). Springer: Dordrecht. 1-278 pp., meer
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| Trefwoorden |
Aquatic communities > Plankton > Phytoplankton
Attenuation > Light attenuation
Biological production > Primary production
Inorganic matter > Suspended inorganic matter
ANE, Nederland, Westerschelde [Marine Regions]
Marien/Kust; Brak water |
| Author keywords |
phytoplankton; primary production; Westerschelde estuary; light attenuation; suspended matter |
| Auteurs | | Top |
- Kromkamp, J.C.
- Peene, J., meer
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| Abstract |
The Westerschelde estuary is a very polluted and turbid estuary, but the last decade the waterquality improved. Dredging activity also increased in 1997 to allow bigger ships to enter the port of Antwerpen. This could potentially decrease the light conditions for the phytoplankton. Because of all these recent changes in the estuary we studied primary productivity in 2001 and compared it to values in 1991. The results show that due to a decrease in discharge in particulate and dissolved organic carbon the oxygen concentrations in general have increased in the upstream region, although in spring and summer low oxygen concentrations (10-30% saturation) can still be found. Phosphate and ammonia concentrations have decreased and the zone of nitrification which was very large in 1991 has become very small and is now located in the uppermost upstream region of the estuary. Si-concentrations have remained the same. All nutrient concentrations are still high enough not to limit phytoplankton growth. Turbidity remained unaltered as a result of the dredging works, and as a result phytoplankton biomass in most of the estuary did not show a decrease, although there were signs that in the upstream region phytoplankton biomass decreased, possible caused by increased grazing pressure. The relationship between phytoplankton biomass and primary productivity did not change, and from the data it can be concluded that the dredging activity will not influence the gross and net primary productivity of the phytoplankton. |
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