Uptake and distribution of Cs-137 and Sr-90 in Salix viminalis plants

Agricultural areas in middle and northern parts of Sweden were contaminated with radionuclides after the Chernobyl accident in 1986. Alternative crops in these areas are biomass plantations with fast-growing Salix clones for energy purposes. The uptake and internal distribution of Cs-137 and Sr-90 in Salix viminalis were studied. Plants were grown in microplots under field conditions. The soils in the experimental site had been contaminated in 1961 with 35.7 and 13.4 M Bq m(-2) of Cs-137 and Sr-90, respectively. The experiment was carried out during three years. The plots were fertilised with 60 kg N ha(-1) and three treatments of K, consisting of 0, 80 and 240 kg K ha(-1), during the first two years. The activity concentration of Cs-137 in the different plant parts varied between 140 and 20,000 Bq kg(-1) and was ranked in the following order: lowest in stems