フォールアウト⁷Beの樹葉への捕捉及び離脱に関する評価

抄録

The capture of radionuclide fallout by tree leaves and the removal mechanism were examined using ⁷Be as a tracer for about two years. Measurement of ⁷Be and ⁴⁰K were performed for the leaves of tea, loquat and fir trees, and the tendency of seasonal variations was investigated. The model, which evaluates the capture and removal of radionuclide fallout on the leaf surface was made on the deposition flux of ⁷Be and precipitation. Conformity and parameter values derived were analyzed. Consequently, massive changes in the concentrations of ⁷Be in the leaves have been recorded according to tree species. The above-mentioned model was effective for evaluating the ⁷Be concentration in the leaves of tea and loquat. The environmental half-life of the ⁷Be concentration was 24 days for tea leaves and 66 days for loquat leaves.