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Stable carbon isotope analysis of subfossil wood from Austrian Alps

Kłusek M., Pawełczyk S.

Geochronometria

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2014

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Vol. 41, no. 4

400--408

EN

The presented studies were carried out in order to check the usefulness of subfossil wood for stable isotope analysis. The aim of research was also to define the optimal method of subfossil samples preparation. Subfossil samples used during the presented studies are a part of the multicentury dendrochronological scale. This chronology originates in an area situated around a small mountain lake — Schwarzersee, in Austria. The obtained results of stable carbon isotope measurements confirmed that the method of α-cellulose extraction by the application of acidic sodium chlorite and sodium hydroxide solutions removes resins and other mobile compounds from wood. Therefore, in the case of the analysed samples, the additional chemical process of extractives removing was found to be unnecessary. Studied wood samples contained an adequate proportion of α-cellulose similar to the values characteristic for the contemporary trees. This proved an adequate wood preservation which is essential for the conduction of isotopic research.

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Hydrogen, carbon and oxygen isotopes in pine and oak tree rings from Southern Poland as climatic indicators in years 1900 - 2003

Szczepanek M., Pazdur A., Pawełczyk S., Böttger T., Haupt M., Hałas S., Bednarz Z., Krąpiec M., Szychowska-Krąpiec E.

Geochronometria

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2006

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Vol. 25

67-76

EN

Carbon, oxygen and hydrogen stable isotopes in tree rings are sensitive indicators of climate changes. We have measured carbon, oxygen and hydrogen isotope ratios in ?-cellulose extracted from annual rings of pine (Pinus sylvestris L.) and oak (Quercus robur L.) growing in the Niepołomice Forest, Southern Poland. The presented isotope records cover the period 1900-2003. In this paper we compare the values of δ13C, δ18O and δ2H observed in the wholewood of pine and in the latewood of oak with meteorological data (temperature, precipitation and sunshine). The highest significant values of correlation coefficients calculated between δ13C and the meteorological data are: -0.26 for temperature, 0.25 for precipitation and 0.41 for sunshine. On the basis of our investigations we deduced that pine is a more sensitive indicator of environmental changes than oak. Our investigation proves that the best indicators are: hydrogen for summer temperature and oxygen for summer precipitation. We noticed a rapid decrease of pine δ13C values in 1966 from -22.46‰ to -24.64‰.

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Radiocarbon concentration measurements in contemporary tree rings from Upper Silesia

Rakowski A. Z., Pawełczyk S., Pazdur A.

Geochronometria

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2000

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Vol. 18

19-22

EN

Upper Silesia is an example of the most industrially changed natural environment in Poland. This state is a consequence of mining development in the last 150 years as well as accumulation of a number of towns and industrial companies with high impact to the environment. A decrease of radiocarbon concentration resulted from the "Suess effect" was observed in the Upper Silesia region. Estimation of this effect, on the basis of carbon isotope analysis in annual tree rings collected from trees growing in the region considered, has been carried out.

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Delta 13C in tree rings alfa-cellulose. A methodology of measurements and interpretation: state of the art

Pawełczyk S., Pazdur A.

Geochronometria

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2000

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Vol. 18

15-18

EN

The development of a tree is dependent upon the climatic and environmental conditions under which it grows. Formed growth rings represent integration of these variables during each growing season. More parameters other than ring-width are required to produce satisfactory reconstruction of past environmental changes. Stable isotope variations within the growth rings may provide other parameters. The variation of delta13C indices in the latewood alpha-cellulose is highly correlated with combined July and August environmental variables. Investigation of isotopic carbon composition in annual tree rings from Upper Silesia and ecologically clean Augustów Wilderness region were recently undertaken in the 14C Laboratory in Gliwice. In that time a series of radiocarbon concentration measurements in single tree rings and delta13C in the entire organic matter were carried out. Such evaluated values of delta 13C are used to correct radiocarbon concentration. However they cannot be used to reconstruct climatic and environmental conditions.