TRANSFER EQUATIONS FOR CESIUM-137 FOR CONIFEROUS FOREST UNDERSTOREY PLANT-SPECIES

The transfer of cesium-137 from organic soil horizons to understorey v egetation has been studied on two coniferous tree sites. In total, 14 different plants preferably taking up their nutirents from organic soi l layers were taken into account. A relatively good correlation was fo und to exist between the transfer factor (Bq/kg plant dry wt./Bq/kg O- horizons dry wt.) for dicotyledons (r = 0.51) and berry plants (r = 0. 63), but there was no correlation for monocotyledons (r = -0.15). The correlations could not be improved by additionally taking potassium in plant and soil into account. These results are discussed in respect t o different parameters influencing the amount of cesium-137 uptake, in cluding plants supported by mycorrhizal fungi.