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Phytoplankton response to climate changes in Lake Baikal during the Holocene and Kazantsevo Interglacials assessed from sedimentary pigments

Journal of Paleolimnology volume 37, pages 177–203 (2007)Cite this article

Abstract

Lake Baikal, an ancient pristine lake in Siberia, has accumulated sediment deposits that span 25 million years. These deposits have the potential to provide a long-term record of climate changes and their interaction with the ecology of the lake. In order to investigate whether sedimentary phytoplankton pigments could be used to reconstruct past changes in total phytoplankton abundance and productivity, we compared the spatial variability in sedimentary pigment distributions in Holocene cores from three separate regions of the lake; Vidrino in the south, Posolski on Selenga Delta and Continent Ridge in the north. Furthermore, we present the first continuous sedimentary pigment and organic carbon sequence of the Kazantsevo interglacial (roughly a time equivalent to the European Eemian, and Marine Isotopic Stage MIS5e) at a resolution of approximately 150 years. Results of the spatial study showed marked differences in the sediment pigment deposition. Lowest chlorophyll a plus its degradation products versus organic carbon ratios (Chlas/TOC) indicating lowest production, but highest variability with time (indicating strongest climatic oscillations) were found at Continent Ridge. The study of sedimentary pigments deposited during the last two interglacial periods at Continent Ridge showed Chlas/TOC ratios 50–1000 times higher during the Kazantsevo Interglacial compared to the glacial periods, whereas the TOC content was only five times higher, thus indicating the significance of the Chlas/TOC ratio for the reconstruction of the phytoplankton abundance and productivity. Strong oscillations occurred during the Kazantsevo Interglacial within centennial time scales. Chlorophyllb plus its degradation products provided additional information on the past development of Chlorophyceae. Highest Chlas/TOC ratios were found during the early Holocene at approximately 9 kyr BP. Indications of short phytoplankton production maxima were also found during the late Atlantic (6 kyr BP) and at the Subboreal/Subatlantic transition (3 kyr BP). From this we conclude that sedimentary chlorophyll a is a reliable indicator of phytoplanktonic response to climate changes and may serve for␣validation of future climate scenarios in continental regions.

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Acknowledgements

This study was realised in the context of EU Framework 5 Project CONTINENT (EVK2-CT-2000-0057). We would like to thank P. Sorrel, F.␣Demory, and J. Klump, GFZ Potsdam, for running the␣GeoTek measurements. We are grateful to the Ms␣A.␣Mueller from the Geoscience Department at University of Potsdam for helping with the ICP OES measurements. We also thank Mrs H. Winkler and Mrs␣M.␣Graupe, IGB Berlin, for helping with HPLC and CN measurements.

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  1. Leibniz Institute of Freshwater Ecology and Inland Fisheries, Mueggelseedamm 301, 12587, Berlin, Germany

    Susanne Fietz

  2. Institute of Biology, Humboldt-University Berlin, Luisenstrasse 53, 10099, Berlin, Germany

    Andreas Nicklisch

  3. GeoForschungsZentrum Potsdam, Telegraphenberg, 14473, Potsdam, Germany

    Hedi Oberhänsli

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Fietz, S., Nicklisch, A. & Oberhänsli, H. Phytoplankton response to climate changes in Lake Baikal during the Holocene and Kazantsevo Interglacials assessed from sedimentary pigments. J Paleolimnol 37, 177–203 (2007). https://doi.org/10.1007/s10933-006-9012-y

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Keywords

  • Chlorophyll
  • Chlorophyceae
  • Degradation
  • Diatoms
  • MIS5e
  • Palaeoproductivity