Ecological Half-Life of 137Cs in Fungi

Abstract

The ecological half-life of 137Cs was calculated individually for four symbiotrophic fungi species (Boletus edulis, Imleria badia, Suillus luteus, Paxillus involutus) at 10 sampling sites in the Chornobyl exclusion zone and in the Kyiv region. It was found that the maximum rate of excretion of 137Cs from the fungi organisms is characteristic for the territory with the maximum levels of soil contamination, i.e., for a zone near Chornobyl Nuclear Power Plant. In areas with low 137Cs content, a slowing down of the excretion rate predominates. These results reveal different fungal response to the distinct concentration levels of 137Cs in forest ecosystems. This observation further suggests that radiocaesium can be selectively accumulated by fungi and used in their life processes. Presence of this 137Cs retention mechanism in fungi leads to a longer contamination of woody plants-symbionts.