This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Kofler, W. Articles by Bortenschlager, S. Search for Related Content GeoRef GeoRef Citation Social Bookmarking                         What's this?

Vegetation responses to the 8200 cal. BP cold event and to long-term climatic changes in the Eastern Alps: possible influence of solar activity and North Atlantic freshwater pulses

University of Innsbruck, Institute of Botany, Sternwartestrasse 15, A-6020 Innsbruck, Austria; Werner.Kofler{at}uibk.ac.at

Veronika Krapf

Walter Oberhuber

Sigmar Bortenschlager

University of Innsbruck, Institute of Botany, Sternwartestrasse 15, A-6020 Innsbruck, Austria

Subfossil pollen from two bogs in temperature-sensitive, high-altitude regions were analysed in order to reconstruct early-to mid-Holocene summer temperature fluctuations in the Eastern Alps. The pollen records showed four centennial-scale cooling intervals with low growing-season temperatures, resulting in decreasing pollen production and/or lower treeline position during the period 9000-6000 cal. BP. For the first time, the 8200 cal. BP cold event and an equivalent to the Misox cold phase in the Swiss Alps were detected in the Eastern Alps. The oscillations recorded in the pollen curves for Swiss stone pine (Pinus cembra) and sedges (Cyperaceae) at c. 8200 cal. BP match, in time and magnitude, the ¹⁸O excursion in the Greenland GRIP ice-core record as well as sea-surface cooling in the North Atlantic. The close congruence between the pollen records covering 3000 years and climate proxy-data from both Hemispheres indicates that large-scale environmental changes, possibly caused by North Atlantic freshwater pulses and/or fluctuations in solar activity, caused decreases in pollen production and/or treeline shifts in the Alps. Although the 8200 cal. BP climatic deterioration was of a global character, its impact on biological productivity of temperature-sensitive sites at high altitude has only rarely been demonstrated. The data indicate that pollen analyses near and above the timberline within high-altitude, herb-dominated plant communities are of considerable and yet largely unexplored potential to detect abrupt short-term as well as long-term climatic variations.

Key Words: Pollen analysis • 8200 cal. BP cold event • Pinus cembra • Cyperaceae • solar forcing • thermohaline circulation • Eastern Alps • early Holocene

The Holocene, Vol. 15, No. 6, 779-788 (2005)
DOI: 10.1191/0959683605hl852ft


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				K. Sarmaja-Korjonen and H. Seppa Abrupt and consistent responses of aquatic and terrestrial ecosystems to the 8200 cal. yr cold event: a lacustrine record from Lake Arapisto, Finland The Holocene, May 1, 2007; 17(4): 457 - 467. [Abstract] [PDF]