The effects of fluvial transport on radionuclide concentrations on different particle size classes

This paper reports on the effects of grain abrasion and disaggregation on the distribution of 137Cs with respect to particle size and the effects this may have on the use of 137Cs for determining the origin of recent sediment. Cs-137 is a product of above ground nuclear testing and has been deposited on the earth's surface by rainfall. On contact with soil, 137Cs is strongly adsorbed by soil particles and there is a direct correlation between 137 Cs concentration and decreasing particle size. Rapid adsorption means that 137Cs is preferentially concentrated in surface soils, and it's subsequent redistribution by physical processes rather than chemical has lead to 137Cs being widely used to study soil erosion. (author). 18 refs., 3 figs., 2 tabs