Biometric measurements of Fragilariopsis kerguelensis, supplement to: Cortese, Giuseppe; Gersonde, Rainer; Maschner, Katharina; Medley, Pamela (2012): Glacial-interglacial size variability in the diatom Fragilariopsis kerguelensis: Possible iron/dust controls? Paleoceanography, 27, PA1208

• Main Authors: Cortese, Giuseppe, Gersonde, Rainer, Maschner, Katharina, Medley, Pamela
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2012
• Subjects: Composite Core; CTD/Rosette; Bongo net; Piston corer BGR type; Gravity corer Kiel type; Leg177; ANT-XVIII/2; ANT-XXI/3; ANT-VI/3; ANT-XI/2; Joides Resolution; Polarstern; International Polar Year 2007-2008 IPY; Paleoenvironmental Reconstructions from Marine Sediments @ AWI AWI_Paleo; Antarctic; Medley; Southern Ocean; The Antarctic; Antarc*; International Polar Year; IPY; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.782735; https://doi.pangaea.de/10.1594/PANGAEA.782735

The valve area of Fragilariopsis kerguelensis, the most abundant diatom species in the Southern Ocean, strongly changes in size in response to varying conditions in the surface ocean. We examined the link, both in two iron fertilization experiments and in sediment samples covering several glacial Terminations, between size variability in this species and environmental conditions across the Antarctic Polar Front, including sea ice extent, sea surface temperature, and the input of eolian dust. The iron fertilization experiments show valve area to be positively correlated with iron concentrations in ambient waters, which suggests the possibility of a causal relation between valve size of Fragilariopsis kerguelensis and ambient surface water iron concentration. Larger valves are usually found during glacial times and thus seem to be related to lower sea surface temperature and wider sea ice coverage. Moreover, our results indicate that there usually is a strong correlation between larger valve size and increased input of eolian dust to the Southern Ocean. However, this correlation, obvious for the fertilization experiments and for glacial Terminations I, II, III, and V, does not seem to be valid for Termination VI, where size appears to be inversely correlated to dust input. : Data included in the frame of a joint ICSTI/PANGAEA IPY effort, see http://doi.pangaea.de/10.1594/PANGAEA.150150