USE OF MOSSES AND LICHENS FOR REGIONAL MAPPING OF CS-137 FALLOUT FROMTHE CHERNOBYL ACCIDENT

The lichens Hypogymnia physodes and Cladonia stellaris and the moss Hy locomium splendens were studied for potential use as biomonitors of th e regional distribution of Cs-137 fallout in Norway from the Chernobyl accident. While Hyl. splendens and C. stellaris showed reasonable mut ual agreement, the activities recorded in the epiphytic species Hyp. p hysodes were not consistent with those of the other species, and depen ded strongly on whether sampling was carried out on conifers or birch. The geographical distribution of Cs-137 in the two former species was in satisfactory agreement with deposition figures obtained from analy sis of surface soil, considering the heterogeneous deposition pattern of Chernobyl radioactivity. Both Hyl. splendens and C. stellaris appea r well suited for regional Mapping of Cs-137 fallout from nuclear acci dents. Regional heavy metal deposition surveys employing Hyl. splenden s might be extended to include radionuclides if desirable.