Fallout Radionuclide Distribution in Lichen Communities near Thule

Abstract

Concentrations of the worldwide fallout radionuclides manganese-54, zinc-65, strontium-90, cesium-137, and cerium-praseodymium-144, and naturally occurring potassium-40 were measured in 80 lichen species collected near Thule, Greenland, during July-August 1968. Emphasis was placed on 137Cs for detailed comparison of radionuclide distribution within the 6 major and 5 minor lichen communities of the 1500 km² area studied. Mean 137Cs concentrations in major lichen species ranged from 22 picocuries per gram standard dry weight in Stereocaulon paschale to 50 pCi/g in Cornicularia divergens, with an overall average of 33 pCi/g. Significant differences were noted between species, habitats and world regions.