Anthropogenic CO₂ Emission Records in Scots Pine Growing in the Most Industrialized Region of Poland from 1975 to 2014

Stable carbon isotope ratios and radiocarbon (¹⁴C) concentrations in samples of pine wood (AD 1975-2012) from 3 sites, as well as needles (AD 2012-2014) collected from 15 sites, in a heavily urbanized area in proximity to heavy industrial factories in Poland were analyzed as bio-indicators of CO₂ emissions. The sampling sites were located at different distances from point sources. The stable isotopic composition was determined using an isotope ratio mass spectrometer, and the ¹⁴C concentration was determined using a liquid scintillation counter and an accelerator mass spectrometer. Spatial and temporal variability of δ¹³C and Δ¹⁴C in tree ring cellulose and needles was noted in all regions. A negative correlation between δ¹³C tree ring cellulose and anthropogenic CO₂ emissions has been observed. The ratio of δ¹³C in tree ring cellulose to δ¹³C in needles created in the same year is equal to 1.2 at the investigated sites.