Microzooplankton herbivory during the diatom-Phaeocystis spring succession in the eastern English Channel

作者：Grattepanche J D; Vincent D; Breton E; Christaki U^*

来源：Journal of Experimental Marine Biology and Ecology, 2011, 404(1-2): 87-97.

DOI：10.1016/j.jembe.2011.04.004

• Coastal ecosystem
• Diatom/Phaeocystis globosa bloom
• Microzooplankton grazing
• Phytoplankton growth
• Size-fractionated dilution

The dilution technique was used to investigate microzooplankton grazing and phytoplankton growth in the eastern English Channel during the diatom-Phaeocystis spring succession from January 2009 to June 2009. Four periods were defined based on phytoplankton composition: Periods 1, 2 and 4 composed of distinct diatom communities of small (5-20 mu m length) to larger cells (20-120 pm) in colonies; Period 3 characterized by the Phaeocystis globosa bloom. Dilution experiments were conducted before, during and after the P. globosa bloom. Microzooplankton carbon consumption (from 18.1 to 360.9 mu g C L(-1) d(-1)) often equalled or exceeded phytoplankton production (from 1.7 to 129.0 mu g C L(-1) d(-1)) in particular at the end of the P. globosa bloom when microzooplankton grazed on previously formed phytoplankton biomass. Results of size-fractionated dilution experiments, conducted with distinct grazer communities, suggested different roles for ciliates and dinoflagellates. Ciliates appeared to be very efficient grazers of small diatoms (5-10 mu m) and P. globosa free cells, whereas dinoflagellates grazed on both larger diatoms (>10 mu m; P1) and small P. globosa colonies. Ciliates and dinoflagellates did not seem to compete for food resources, as they were oriented towards different phytoplankton size classes.

• 出版日期2011-7-31