DETERMINATION OF COPPER, IRON, NICKEL, AND SULFUR BY X-RAY-FLUORESCENCE IN LICHENS FROM MACKENZIE-VALLEY, NORTHWEST-TERRITORIES, AND SUDBURY-DISTRICT, ONTARIO

X-ray fluorescence was adapted to the analysis of 22 terricolous lichen species from 14 sites in the Mackenzie Valley, Northwest Territories, and 7 spp. from the Sudbury District of N Ontario, Canada. X-ray fluorescence (XRF) proved faster and exhibited better sensitivity and reproducibility than conventional analytical techniques; the samples were not destroyed in the analysis. Procedural details of the XRF method are given. The levels of Cu, Fe, Ni and S in Arctic lichens were similar to those in lichens growing on the periphery of the Sudbury pollution zone but very much lower than in specimens nearer the Ni smelter. A linear relationship between concentration and the reciprocal of the distance from the Copper Cliff smelter was confirmed for the occurrence of these 4 elements in samples collected along a 60 mi NNW transect.