Secondary ion mass spectroscopy and synchrotron X-ray fluorescence in the study of the qualitative variation in metal content with time in tree rings

Secondary ion mass spectroscopy and synchrotron X-ray fluorescence analysis have been used to document the changes in metal content across the ring sy stem of trees from northern Canada. The results show a seasonal qualitative variation in the uptake of Na, Al, K, Ca, Cr, Mn, Fe, Cu, and Zn. Diffusio nal models show that locally elevated concentrations of selected metals are sufficiently stable within individual rings that variations in content amo ng rings remain at detectable levels for at least a century.