Abstract: | This paper describes the application of a mechanistic model in the study of radionuclide soil–plant transfer and the obtainment
of predictive estimates of radionuclide plant contamination. Soil–plant K and 134Cs transfer rates were measured and compared with those predicted by the Barber–Cushman model. The experiment was performed
on pea plants grown in pots and in two different types of soil (Calcic Luvisol and Fluvisol). For K, model predictions proved valid for all development stages sampled; for 134Cs, the quality of the prediction depended on the plant stage. In both, parameter estimates varied depending on plant age
and soil type. The model was also run for 134Cs using the Michaelis–Menten parameters obtained for K. In this case, the predicted values were significantly correlated
with those measured, but about three times higher. Thus, a positive plant discrimination of K versus
134Cs in plant absorption is observed for the types of soil studied. As regression proved to be significant, K absorption rates
may be used to estimate 134Cs absorption in determining radiocaesium plant uptake.
This revised version was published online in June 2006 with corrections to the Cover Date. |