Lichens and mosses as monitors of industrial activity associated with uranium mining in northern Ontario, Canada—Part 3: Accumulations of iron and titanium and their mutual dependence

Strong linear regressions (P < 0·001) were observed between background concentrations of iron and titanium in lichens and mosses. For these same samples, the Fe/Ti content ratio was remarkably constant: 8·7 ± 1·8 for fifty-four lichen samples and 10·5 ± 1·5 for thirty-eight mosses. The Fe/Ti concentration ratio for cryptogams collected near uranium mine-exhaust vents accurately reflected the values of this same ratio for the rocks characterising the local ore body. Plant samples exhibiting the largest levels of Fe and Ti also had high mineral ash contents. The various associations and observations reported were interpreted as evidence that particulate trapping is an important elemental accumulation mechanism for lichens and mosses.