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2 Geochronometria

2 2006

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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

2006

Vol. 25

67-76

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‰.

Carbon and oxygen isotope composition of organic matter and carbonates in recent lacustrine sediments

Sensuła B., Böttger T., Pazdur A., Piotrowska N., Wagner R.

Geochronometria

2006

Vol. 25

77-94

The distribution of stable isotopes (18O and 13C) and radiocarbon in organic materials, carbonates and water samples collected from the environment of lacustrine sediments in Gościąż Lake (Central Poland) and Wigry Lake (NE Poland) were investigated. The oxygen and carbon isotopic analysis of terrestrial semi submerged and submerged plants, shells and water samples were compared with the results of the uppermost sediments from lakes. It was found that the concentration of isotopes in different components of organic and carbonate materials in lakes and their environments are reflected in isotope composition averaging of lakes sediments, whereas the isotope composition of plants and carbonate depends on biogeochemical factors. The research carried out revealed significant variations in the distribution of the stable isotopes and 14C in different elements of lacustrine ecosystem. We have analyzed mean values and variations of 14C concentration, δ18O, δ13C of plants, carbonates and the relationship between the total content of carbon and δ13C. In the case of plants, the isotope composition depends also on the physiognomy and the photosynthesis pathway. We noticed variations in δ13C and δ18O within plant tissues, variations in δ13C among whole tissue material and alphacellulose, carbon isotopic composition of photosynthetically fixed carbon and syntaxonomic dependences and then we compared the results of isotope composition of plants and carbonates in Wigry Lake and Gościąż Lake.