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Marine Biology

, Volume 149, Issue 3, pp 625–632 | Cite as

The tunicate Salpa thompsoni ecology in the Southern Ocean. II. Proximate and elemental composition

  • Corinna D. Dubischar
  • E. A. Pakhomov
  • U. V. Bathmann
Research Article

Abstract

Detailed determination of Salpa thompsoni elemental composition has been carried out on specimens collected in the Eastern Bellingshausen Sea and at the northern edge of the Weddell Gyre during austral autumn (April and May) of 1996 and 2001. More than 170 Antarctic tunicates S. thompsoni were analysed to determine wet weight (WW), dry weight (DW), ash-free dry weight (AFDW) and elemental composition (C, N content, proteins, carbohydrates and lipids) of different sizes and stages. Dry weight comprised 6.4% (aggregate form) to 7.7% (solitary form) of the WW. AFDW amounted to ~44% of the DW. Carbon and nitrogen contents (Carbon: 17–22%, Nitrogen: 3–5% of the DW) of both aggregate and solitary forms were found to be high relative to data reported in the literature. Although some unidentified organic compounds are not included in our carbon budget, the findings of this study show higher than previously reported nutritional values of S. thompsoni. In spite of this, a shift from a krill-dominated towards a salp-dominated ecosystem would have dramatic consequences for organisms at higher trophic levels.

Keywords

Southern Ocean Aggregate Form Gelatinous Zooplankton Lower Lipid Content Faecal Pellet Production 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

We wish to thank the captain, officers and crew of the RV “Polarstern” for their skilful help throughout both cruises. Special thanks are due to Eberhard Fahrbach (chief scientist during the ANT XIII/4-cruise) who greatly supported the work of a small biology group in the middle of a large group of oceanographers with lots of tasks. We also wish to thank Christian Hamm, Richard Crawford and two anonymous reviewers for carefully reading the manuscript and their very helpful comments. This work was partly funded by a grant of the Alexander von Humboldt-Stiftung for E.A.P.

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Corinna D. Dubischar
    • 1
  • E. A. Pakhomov
    • 1
    • 2
    • 3
  • U. V. Bathmann
    • 1
  1. 1.Alfred Wegener Institute for Polar and Marine ResearchBremerhavenGermany
  2. 2.Department of Earth and Ocean SciencesUniversity of British ColumbiaVancouverCanada
  3. 3.Zoology Department, Faculty of Science and TechnologyUniversity of Fort HareAliceSouth Africa

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