An analysis of the element content of lichens from the Northwest Territories, Canada

• Published in: Canadian Journal of Botany
• Main Authors: Puckett, K. J., Finegan, E. J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1980
• Subjects: Northwest Territories
• Online Access: http://dx.doi.org/10.1139/b80-240; http://www.nrcresearchpress.com/doi/pdf/10.1139/b80-240

The results of a survey of the element content of saxicolous and terricolous lichens collected from the Northwest Territories, Canada, are summarized. Fourteen lichen species were collected from 45 sites and the lichens were analysed for 20 elements by instrumental neutron activation and X-ray fluorescence.An enrichment factor (EF) was calculated for each element analysis. The elements aluminium, chromium, iron, sodium, titanium, and vanadium had mean EF values of 1–5 for all species. These low EF values indicated that, relative to average values for crustal rock, there was no enrichment of these elements in the lichens concerned. For other elements (chlorine, lead, and sulphur) consistently higher EF values were obtained. These higher values were interpreted in terms of (a) differing methods of element accumulation, (b) sources of elements both natural and anthropogenic other than crustal rock and (or) soil, and (c) marked deviations of the actual substrate concentrations from the average crustal-rock concentrations used.The underlying structure of the data from some species was investigated using ordination techniques. These techniques provided some description of the element associations within the lichen thallus. These element associations were examined in relation to sources external to the plant. A principal component analysis was carried out on the data for each of three species, Cetraria cucullata, C. nivalis, and Cladina stellaris. In all cases, the first five principal components explained 81–89% of the variation in the data. One component which had high weightings for aluminium, scandium, and vanadium (with or without iron, nickel, and titanium) was common to all three species. Similarly, a second component with high weightings for calcium (with or without magnesium and potassium) was a consistent feature of each analysis. These and other components were considered in the context of lichen enrichment from crust-derived particulates, the marine aerosol, and certain anthropogenic sources. The high ...