Transfer of fission products from soil to crops

16 Transfer of fission products from soil to crops 

The factors which determine uptake from soil are complex. Among the variables are  

Uptake from soil is often expressed as a concentration factor (activity 

Uptake of137Cs from soil was also studied in the 1960s (Frederiksson et al., 1966) and there has been renewed interest in relation to the longterm effects of the Chernobyl accident. The uptake is very dependent on the type of soil. In normal agricultural soils, Cs, like K, is fixed on the cation-exchange sites in the clay fraction. Within plants, Cs is more mobile than Sr, and it is translocated more readily from leaves to seeds (Middleton, 1959). It can also be absorbed from the matt horizon at the top of the soil, as this comprises organic material, but uptake from normal soils becomes small once Cs is fixed on the clay fraction. In Table 2.21, the data for UK, US and Denmark shows that B only slightly exceeds bx + b2. 

The situation is different when the clay fraction is very small, as is the 

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