We investigated the transfer of radiocesium and its behavior in living cells and cellular debris in a Chlamydomonas spp. bloom in a pond located approximately 5 km from the Fukushima Dai-ichi Nuclear Power Plant. A microalgal bloom in the pond was the dominant factor in determining the radiocesium concentration (Bq/L) of the > 0.45 μm pond water fraction. The water-to-algae transfer factor [(¹³⁷Cs concentration Bq/kg_{>0.45 μm fraction}) × (¹³⁷Cs concentration Bq/L_{<0.45 μm water})⁻¹] was 1.6 × 10³. The transfer factor was similar for filamentous algae attached to the wall of the pond, and suggesting that radiocesium transfer to algae was through water, not directly from sediment. Intact microalgal cells and cellular debris displayed nearly equal ¹³⁷Cs concentrations, and radiocesium was also transferred in cellular debris as well as living algal cells. The water-to-algae transfer factor in this study is two to three orders of magnitude lower than previously reported radiocesium concentration ratio of suspended solid (> 0.45 μm) and water in rivers in Fukushima [(¹³⁷Cs concentration Bq/kg_{>0.45 μm fraction}) × (¹³⁷Cs concentration Bq/L_{<0.45 μm water})⁻¹].

我们研究了放射性铯的转移及其在衣藻中活细胞和细胞碎片中的行为。在距离福岛第一核电站约 5 公里的池塘中开花。池塘中的微藻大量繁殖是决定 > 0.45 μm 池塘水部分的放射性铯浓度 (Bq/L) 的主要因素。水对藻的转移因子[( ¹³⁷ Cs 浓度Bq/kg _{>0.45 μm 分数}) × ( ¹³⁷ Cs 浓度Bq/L _{<0.45 μm 水}) ^-1 ] 为1.6 × 10 ³. 附着在池塘壁上的丝状藻类的转移因子相似，这表明放射性铯通过水转移到藻类，而不是直接从沉积物中转移。完整的微藻细胞和细胞碎片显示出几乎相等的¹³⁷ Cs 浓度，并且放射性铯也转移到细胞碎片和活藻细胞中。本研究中的水-藻转移因子比先前报道的福岛河流中悬浮固体（> 0.45 μm）和水的放射性铯浓度比低两到三个数量级[（¹³⁷ Cs 浓度 Bq/kg _{>0.45 μm分数}) × ( ¹³⁷ Cs 浓度 Bq/L _{<0.45 μm 水}) ^-1 ]。