Synchrotron x-ray fluorescence and secondary ion mass spectrometry in tree ring microanalysis: Applications to dendroanalysis

Mining operations in the Sudbury district of northern Ontario have resulted in environmental damage caused by acid rain and heavy metal pollution. Remedial liming (Ca/MgCO₃) has been used in an attempt to restore the pH of the lake water and soil to natural levels. The spatial and temporal variation of metal concentrations in the annual growth rings of trees may be a useful indicator of the effects of the pollutants and the liming operation. We used synchrotron radiation-induced x-ray emission (SRIXE) and secondary ion mass spectrometry (SIMS) to examine the distribution of selected metals in the annual growth rings of red pine (Pinus resinosa) from an area damaged by acid rain and heavy metal pollution which had been subjected to remedial liming (Ca/MgCO₃). The results show a non-uniform distribution of metals in the stemwood, including seasonal variations and changes in the Ca/Mn ratio consistent with the increased soil pH following liming.