Articles | Volume 32, issue 2
https://doi.org/10.1144/jmpaleo2012-022
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.1144/jmpaleo2012-022
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
The Helgoland Experiment – assessing the influence of methodologies on Recent benthic foraminiferal assemblage composition
Joachim Schönfeld
GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, D-24148 Kiel, Germany
Elena Golikova
Department of Invertebrate Zoology, Faculty of Biology and Soil Science, St Petersburg State University, Universitetskaya nab. 7/9, 199034, St Petersburg, Russia
Sergei Korsun
Department of Invertebrate Zoology, Faculty of Biology and Soil Science, St Petersburg State University, Universitetskaya nab. 7/9, 199034, St Petersburg, Russia
Silvia Spezzaferri
University of Fribourg, Department of Geosciences, Chemin du Musée 6, 1700 Fribourg, Switzerland
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Short summary
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Benthic foraminifera from the Bottsand coastal lagoon, western Baltic Sea, have been monitored annually since 2003 and accompanied by hydrographic measurements since 2012. Elphidium incertum, a stenohaline species of the Baltic deep water fauna, colonised the lagoon in 2016, most likely during a period of salinities > 19 units and average temperatures of 18 °C in early autumn. The high salinities probably triggered their germination from a propagule bank in the lagoonal bottom sediment.
J. Schönfeld, W. Kuhnt, Z. Erdem, S. Flögel, N. Glock, M. Aquit, M. Frank, and A. Holbourn
Biogeosciences, 12, 1169–1189, https://doi.org/10.5194/bg-12-1169-2015, https://doi.org/10.5194/bg-12-1169-2015, 2015
Short summary
Short summary
Today’s oceans show distinct mid-depth oxygen minima while whole oceanic basins became transiently anoxic in the Mesozoic. To constrain past bottom-water oxygenation, we compared sediments from the Peruvian OMZ with the Cenomanian OAE 2 from Morocco. Corg accumulation rates in laminated OAE 2 sections match Holocene rates off Peru. Laminated deposits are found at oxygen levels of < 7µmol kg-1; crab burrows appear at 10µmol kg-1 today, both defining threshold values for palaeoreconstructions.
K. Haynert, J. Schönfeld, R. Schiebel, B. Wilson, and J. Thomsen
Biogeosciences, 11, 1581–1597, https://doi.org/10.5194/bg-11-1581-2014, https://doi.org/10.5194/bg-11-1581-2014, 2014
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