137Cs concentrations in mushrooms collected in 1989-2000 at different forest stands in Kivalo experimental area

The accumulation rate for different mushroom species varies, but there does not seem to be any clear correlation between the 137 Cs concentrations (Bq/kg fw) in the 1990-1991 mushrooms and the length of the ecological half-life. This is despite the fact that the highest concentrations have been measured in Cortinarius armillatus, the ecological half-life of which appears to be of the order of the physical T of 137 Cs, 30 y. All the Russula species have had low concentrations, although the half-lives are rather long 11-18 y. Lactarius trivialis has highers levels than the other analysed Lactarius species but there is no correlation with the half-lives. The type of forest stand does not seem to have any ef-fect on the caesium concentrations, except possibly for Rozites. (AU)