Microphytobenthos of the Dogger Bank: a comparison between shallow and deep areas using phytopigment composition of the sediment
- 98 Downloads
The surface sediment characteristics related to benthic microalgae primary production were studied at the Dogger Bank, North Sea, in order to evaluate the potential role of microphytobenthos as a food source for the macrobenthic fauna. Twenty-one stations were sampled in July 2001 and May 2002, with water depth ranging from 16.3 to 68.5 m. High-performance liquid chromatography pigment analyses revealed that concentrations of chlorophyll a, chlorophyll c and fucoxanthin are mainly associated with benthic diatom flora at most parts of the Dogger Bank. High percentage of phytopigments (>50%) was firmly attached to sand grains at the stations shallower than 40 m water depth. The deeper stations were characterized by a phytopigment composition originating from pelagic phytoplankton settled on the sea floor. Qualitative microscopy showed that the benthic microflora on top of the Bank mainly consists of small diatoms (5–10 μm), such as e.g., Diploneis spp., living attached to the sand grains. The results are discussed concerning possible implications for ecology and biogeochemistry of the Dogger Bank area.
KeywordsExtracellular Polymeric Substance Fucoxanthin Benthic Diatom Deep Station Total Organic Carbon Concentration
The authors wish to thank the captain and the crew of the RV “Senckenberg” for their help with sampling as well as T. Janßen and C. Plum for technical assistance. We are grateful to H. Freund, Research Centre Terramare Wilhelmshaven for identification of the diatoms and W. Ahlrichs and I. Notholt of the University of Oldenburg for providing the opportunity to use the SEM. We are also grateful to three anonymous referees for helpful comments on the manuscript.
- Abele D (1988) Carotinoide als biogene Marker für benthische Makroalgen im Sediment der Kieler Bucht. Berich Instituts Meereskunde Kiel 183:1–116Google Scholar
- Brockmann U, Wegner G (1985) Hydrography, nutrient and chlorophyll distribution in the North Sea in February 1984. Arch Fisch Wiss 36:27–45Google Scholar
- Howarth MJ, Dyer KR, Joint IR, Hydes DJ, Purdie DA, Edmunds H, Jones JE, Lowry RK, Moffat TJ, Pomroy AJ, Proctor R (1993) Seasonal cycles and their spatial variability. Philos Trans R Soc Lond A343:383–403Google Scholar
- Remane A (1940) Einführung in die zoologische Ökologie der Nord- und Ostsee. Die Tierwelt der Nord- und Ostsee, Akademische Verlagsgesellschaft, LeibzigGoogle Scholar
- Richardson K, Olsen OV (1987) Winter nutrient concentrations and primary production in the eastern North Sea. ICES CM1987/C 23:15Google Scholar
- Sundbäck K, Persson L-E (1981) The effect of microbenthic grazing by an amphipod, Bathyporeia pilosa, Lindström. Kieler Meeresforschung Suppl 5:573–575Google Scholar
- Tenore KR (1988) Nitrogen in benthic food chains. In: Sorensen J, Blackburn TH (eds) Nitrogen cycling in coastal marine environments. Wiley, New York, pp 191–206Google Scholar
- Wieking G, Kröncke I (2003) Macrofauna communities of the Dogger Bank (central North Sea) in the late 1990s: spatial distribution, species composition and trophic structure. Helgoland Mar Res 57:34–46Google Scholar