Late quaternary ecological turnover in high arctic lake einstaken, nordaustlandet, svalbard (80° n)

Abstract

Luoto, T.P., Nevalainen, L., Kubischta, F., Kultti, S., Knudsen, K.L. and Salonen, V.‐P., 2011: Late Quaternary ecological turnover in high arctic Lake Einstaken, Nordaustlandet, Svalbard (80° N). Geografiska Annaler: Series A, Physical Geography, 93, 337–354. DOI:10.1111/j.1468‐0459.2011.00435.x

Abstract

Multiproxy palaeolimnological analyses of a sediment core record from Lake Einstaken, Nordaustlandet, give insight into long‐term ecological and environmental dynamics in the High Arctic Svalbard during the last c. 13-000 cal yr bp. Fossil remains of foraminifera, chironomidae, cladocera and diatoms (Bacillariophyta) revealed several distinct ecological turnovers during the late Quaternary. The foraminiferal assemblages in a marine interval in the lower part of the core indicated one distinct faunal turnover and two subsequent minor changes. The foraminiferal assemblages reflected high‐arctic, shallow‐water conditions in an area of changing salinity conditions. A development of gradually more restricted marine conditions, presumably related to a decrease in water depth during the isostatic uplift, was evident from the foraminiferal assemblages. The Holocene was characterized by a freshwater environment in the isolated Lake Einstaken. The cladoceran assemblages experienced two complete faunal turnovers in the early part of the lacustrine sediment sequence, most likely related to inlake processes. The chironomid assemblages went through five distinct Holocene faunal changes that were probably mostly related to climate development and changes in nutrient conditions. The freshwater diatoms revealed four distinct episodes of change in their assemblages that could be related to their sensitivity to pH and nutrient status. The most distinct common feature in the Holocene faunal and floral assemblages was the pioneer phase during the early Holocene. The recent environmental changes, which were most visibly reflected in the chironomid records, are possibly related to a coupled effect of elevated nutrient conditions and increased temperatures.

Key words:

• Chironomidae
• Cladocera
• diatoms
• Foraminifera
• Holocene
• Nordaustlandet
• palaeolimnology
• Svalbard

Acknowledgements

We are grateful to Anu Kaakinen and Stig Gøystad for their help with the field work and to Antti Ojala for his support in sample preparation. This study was financed by the Academy of Finland (project 1116509). Additional personal funding was provided by the Kone Foundation (the LOSER project, LOng‐term climate impactS on lakE tRophic status) for T.P. Luoto and by the Waldemar von Frenckell's Fund for L. Nevalainen. We are grateful to the two anonymous reviewers for their valuable comments on the manuscript.

Additional information

Notes on contributors

Tomi P. Luoto

Tomi P. Luoto, Institute for Limnology, Austrian Academy of Sciences, Mondseestraße 9, A‐5310 Mondsee, Austria and Department of Geosciences and Geography, P.O. Box 64, FI‐00014 University of Helsinki, Finland.

E‐mail: [email protected]

Liisa Nevalainen

Liisa Nevalainen, Institute for Limnology, Austrian Academy of Sciences, Mondseestraße 9, A‐5310 Mondsee, Austria

Frauke Kubischta

Frauke Kubischta, Department of Geosciences and Geography, P.O. Box 64, FI‐00014 University of Helsinki, Finland

Seija Kultti

Seija Kultti, Department of Geosciences and Geography, P.O. Box 64, FI‐00014 University of Helsinki, Finland

Karen Luise Knudsen

Karen Luise Knudsen, Department of Earth Sciences, Aarhus University, Høegh‐Guldbergs Gade 2, DK‐8000 Århus C, Denmark

Veli‐pekka Salonen

Veli‐Pekka Salonen, Department of Geosciences and Geography, P.O. Box 64, FI‐00014 University of Helsinki, Finland