The bio-availability of long-lived radionuclides in relation to their physico-chemical form in soils

Two of the major aspects affecting the behaviour of radionuclides in soil/plant systems are studied: availability in the soil liquid in relation to major characteristics of the soil, and the efficiency of the uptake process. The nuclide of main interest is Cs-137, although some experiments on transuranics are planned as well. The final goal is a generalized description of the relation between the concentration and species of a radionuclide present in the solid phase of the soil, in the liquid phase and in biota. Results of the four contributions to the project for the reporting period are discussed. (R.P.) 4 figs., 10 tabs