Accumulation of 137Cs by Cladonia Lichens in the Impact Zone of the Kola Nuclear Power Plant

The accumulation of 137 Cs and its stratification in Cladonia lichens growing in the area of Kola nuclear power plant have been studied. For this purpose, samples of reindeer lichens were selected at 12 test sites in the sanitary protection zone of the station, in the observation zone, and in the background area. The specific activities of 137 Cs in the samples were determined using a scintillation gamma spectrometer. The weighted average specific activities of 137 Cs in Cladonia lichens were 22.3–104.8 Bq/kg, while most of the radiocaesium was concentrated in the upper layers of the lichen. Statistical data processing using a single-sample t -test, Spearman’s coefficient, and cluster analysis indicated the dominant role of global fallout in the 137 Cs input into the lichens, while the possible impact of the Kola nuclear power plant on this process is limited to the sanitary protection zone.