Paleontological records indicate the occurrence of open woodlands in a dry inland climate at the present-day Arctic coast in western Beringia during the Last Interglacial


Contact
fkienast [ at ] senckenberg.de

Abstract

Permafrost records, accessible at outcrops along the coast of Oyogos Yar at the Dmitry Laptev Strait, NE-Siberia, provide unique insights into the environmental history of Western Beringia during the Last Interglacial. The remains of terrestrial and freshwater organisms, including plants, coleopterans, chironomids, cladocerans, ostracods and molluscs, have been preserved in the frozen deposits of a shallow paleo-lake and indicate a boreal climate at the present-day arctic mainland coast during the Last Interglacial. Terrestrial beetle and plant remains suggest the former existence of open forest-tundra with larch (Larix dahurica), tree alder (Alnus incana), birch and alder shrubs (Duschekia fruticosa, Betula fruticosa, Betula divaricata, Betula nana), interspersed with patches of steppe and meadows. Consequently, the tree line was shifted to at least 270. km north of its current position. Aquatic organisms, such as chironomids, cladocerans, ostracods, molluscs and hydrophytes, indicate the formation of a shallow lake as the result of thermokarst processes. Steppe plants and beetles suggest low net precipitation. Littoral pioneer plants and chironomids indicate intense lake level fluctuations due to high evaporation. Many of the organisms are thermophilous, indicating a mean air temperature of the warmest month that was greater than 13 °C, which is above the minimum requirements for tree growth. These temperatures are in contrast to the modern values of less than 4 °C in the study area. The terrestrial and freshwater organism remains were found at a coastal exposure that was only 3.5. m above sea level and in a position where they should have been under sea during the Last Interglacial when the global sea level was 6-10. m higher than the current levels. The results suggest that during the last warm stage, the site was inland, and its modern coastal situation is the result of tectonic subsidence. © 2010 Elsevier Ltd.



Item Type
Article
Authors
Divisions
Programs
Peer revision
ISI/Scopus peer-reviewed
Publication Status
Published
Eprint ID
22837
DOI https://www.doi.org/10.1016/j.quascirev.2010.11.024

Cite as
Kienast, F. , Wetterich, S. , Kuzmina, S. , Schirrmeister, L. , Andreev, A. A. , Tarasov, P. , Nazarova, L. , Kossler, A. , Frolova, L. and Kunitsky, V. V. (2011): Paleontological records indicate the occurrence of open woodlands in a dry inland climate at the present-day Arctic coast in western Beringia during the Last Interglacial , Quaternary Science Reviews, 30 (17-18), pp. 2134-2159 . doi: https://www.doi.org/10.1016/j.quascirev.2010.11.024


Download
[thumbnail of Fulltext]
Preview
PDF (Fulltext)
Kie2010b.pdf

Download (10MB) | Preview
Cite this document as:

Share


Citation

Research Platforms
N/A

Campaigns
N/A


Actions
Edit Item Edit Item