Radioactive Cs was investigated in the samples of 38 macromycete species, mosses (unspecified), Calluna vulgaris, Vaccinium myrtillus, lichens (Cladonia subgenus Cladina) as well as forest litter, upper (0–5 cm) and lower (5–20 cm) soil layers. Samples were collected during the period of 1992–1995 in the regions of highest, medium and lowest pollution with Chernobyl radiocesium. Activity of radiocesium was established in the most common macromycete species of Lithuania. Dependance of Cs activity in fungi upon habitat and substrate is discussed and dynamics in the fruit bodies of fungi during 1986–1995 is presented. Comparative investigations on radiocesium were carried out in fungi and some forest plants collected at the same time under identical conditions.
Keywords: radioactive cesium, concentration, dynamics, macromycetes, Lithuania.