On the copepod response to iron induced phytoplankton blooms in the Southern Ocean

• Other Authors: Krägefsky, Sören
• Language: English
• Published: Niedersächsische Staats- und Universitätsbibliothek 2008
• Subjects: 590; Austral; Southern Ocean; Copepods
• Online Access: http://webdoc.sub.gwdg.de/ebook/dissts/Bremen/Kraegefsky2008.pdf; http://elib.suub.uni-bremen.de/diss/docs/00011275.pdf; http://d-nb.info/992926106/34; http://nbn-resolving.de/urn:nbn:de:gbv:46-diss000112756

This thesis investigates the response of copepods to increased phytoplankton abundance during two mesoscale iron-fertilisation experiments in the Southern Ocean (EisenEx in austral spring 2001 and EIFEX in austral autumn 2004), focussing on the copepods vertical migration behaviour. The horizontal and vertical distribution of zooplankton was surveyed by acoustic methods (multi-frequency echosounder Simrad EK60), which generated data with high spatial and temporal resolution. In addition to the acoustic measurements and to identify acoustic scatterer, net samples were taken and analysed. Mathematical models which take into account the copepod behaviour and the prevailing current regimes were developed and used to interpret the population dynamics during the experiments. To assess trophic interaction within the pelagic ecosystem,ingestion rates of the dominant copepod species were measured during both experiments. During EIFEX, faecal pellet production, egg production and gut content of copepods were investigated in addition. The combination of these diverse methods provided new insights in the behaviour of copepods. Univ., Diss--Bremen, 2008