Preliminary analysis of first crop of plants grown in seven soils uniformly contaminated with four transuranic elements simultaneously. Quarterly progress report

A forage crop and a grain crop of wheat were harvested from a replicated experiment with about 200 kg soil per container in which seven soils from different locations throughout the U.S.A. were spiked with four different transuranic elements simultaneously. Concentration Ratios (C.R.) for the radioactive elements in plants were obtained as a start to careful examination of parameters involved in the use of these ratios in models. The relative availability of the different radionuclides differed considerably with soil. One order of magnitude differences were common for element pairs. In general the order of plant availability was Np > Am > Cm > Pu. The differences that were encountered for soil for radionuclides present in straw were much less pronounced in the grain. The ratio of maximum(usually for the acid sandy soil) to minimum (usually for the soil with high soil organic matter) for straw varied from 1.9 to 2.5 orders of magnitude, but was one order or less for grain. This means that a small and more constant amount of transuranium element is transferred to grain relative to that in straw. The behavior is somewhat analogous to that of calcium. The results are to be very useful in refiningmore » of models.« less