In: Phyton, 52 Fasc. 1 (2012), S. 101-119, with 7 figures

Key words: Conifers, Larix, Picea, Pinus. – Dendrochronology, light-ring formation, wood anatomy. – Climate, extreme weather conditions. – Russia, Siberian northern taiga.

Summary

GURSKAYA M. A., HALLINGER M., ECKSTEIN D., & WILMKING M. 2012. Extreme cold summers in western Siberia, concluded from light-rings in the wood of conifers. – Phyton (Horn, Austria) 52 (1): 101–119, with 7 Figures.

Wood samples of larch (Larix sibirica LEDEB), spruce (Picea obovata LEDEB.) and pine (Pinus sibirica DU TOUR), growing in the northern taiga of western Siberia, were screened for the occur-rence of light-rings – an anomaly of tree-ring formation in extreme environments. Light-rings were dated and the resulting species-related light-ring chronologies were used (1) to explore possible causes of light-ring formation and (2) to reconstruct past extreme climatic events. Light-rings in spruce and larch were mainly formed by an unusually cool May, June, August and September, whereas light rings in pine were associated with a cool July. Between 1740 and 1997 we identified seven years when all three species had formed light-rings and 15 years when light-rings were formed in larch and spruce, but not in pine. As concluded from linear regression, summer temperatures explained 43 and 50% of the variability of light-ring intensity in spruce and larch, respectively. However, not all light rings were formed in below-average cold summers but in a few cases even in above-average warm summers, indicating the limitation of this approach.