Recent studies on the interception and the retention of caesium by grass, barley and peas

Experiments with artificial depositions of radio caesium during the growth period have been carried out. The studies are complementary to experiences after the Chernobyl fallout and aimed at a description of the relative transfer to the harvest products of grass, barley and peas after initial interception during growth. It was found that the apparent residence half-time of caesium in grass on old established leys producing winter feed was about one month and that the reduction in nuclide content up to the harvest time for this reason mainly depended on dilution by growth. Also the grain crops were found to be sensitive to depositions during almost the whole season. It should be due to translocation of caesium within the plant. The data obtained can make the basis for prediction of the consequences of fallouts. (au)