Hydrogen, carbon and oxygen isotopes in pine and oak tree rings from Southern Poland as climatic indicators in years 1900-2003. Geochronometria 25

Abstract: 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 α-cel-lulose extracted from annual rings of pine (Pinus sylvestris L.) and oak (Quercus robur L.) growing in the Niepoomice 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 calcu-lated between δ13C and the meteorological data are:-0.26 for temperature, 0.25 for precipita-tion 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‰. Key words