A COMPARATIVE-STUDY ON RADIOCESIUM (CS-137) UPTAKE FROM CONIFEROUS FOREST SOIL

Radiocaesium (Cs-137) uptake from a coniferous forest ecosystem with s oil characterized by a high fraction of organic matter and low pH was studied using sheep's fescue (Festuca ovina) as indictor in a pot expe riment and compared with bilberry (Vaccinium myrtillus), lingonberry ( Vaccinium vitis-idaea), and heather (Calluna vulgaris) taken from an a rea of coniferous forest, Results obtained on an average basis showed a slight variation within Cs-137 uptake values in all tested plants. B ased upon the soil-plant relationship (Bqkg(-1) plant DM/Bq kg(-1) soi l DM), Cs-137 transfer factors (TF) were calculated. Sheep fescue TF i n the two harvests (growing periods of 13 weeks each) ranged from 0.03 to 3.45, with a mean of 0.35 +/- 0.42. Field plants showed higher Cs- 137 TF when compared with sheep's fescue. Bilberry TF ranged from 0.28 to 2.30, with a mean of 0.85 +/- 0.49. Lingonberry TF ranged from 0.5 7 to 4.46 with a mean of 1.35 +/- 0.78. Heather TF ranged from 1.80 to 8.89 with a mean of 3.31 +/- 1.53. Radiocaesium transfer coefficients (TC, Bqkg(-1) plant DM/Bq m(-2)) of field plants were also calculated Heather Cs-137 TC was the highest among all tested plants and ranged from 0.38 to 0.64 with a mean of 0.49 +/- 0.05. The results demonstrat ed that Cs-137 transfer. parameters of pot experiment with sheep's fes cue show no significant differences between the obtained transfer fact ors, using soils from bilberry, lingonberry, and heather sites.