検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年

Temporal change in atmospheric radiocesium during the first seven years after the Fukushima Dai-ich Nuclear Power Plant accident

福島第一原子力発電所事故から7年間における大気中放射性セシウムの経時変化

阿部 智久 ; 吉村 和也 ; 眞田 幸尚  

Abe, Tomohisa; Yoshimura, Kazuya; Sanada, Yukihisa

After the Fukushima Dai-ichi Nuclear Power Plant accident, atmospheric radiocesium concentration has been monitored by the Nuclear Regulation Authority (NRA) as a national project to assess its temporal change from August 2011 to November 2017. During the first two years, the atmospheric radiocesium concentration ranged between 10$$^{-1}$$ - 100 Bq m$$^{-3}$$, while concentrations of 10$$^{-5}$$ - 10$$^{-1}$$ Bq m$$^{-3}$$ were detected about seven years after the accident. Moreover, two years after the accident, the resuspension factor (RF) ranged between 10$$^{-7}$$ - 10$$^{-6}$$ m$$^{-1}$$ and gradually decreased to 10$$^{-11}$$ - 10$$^{-7}$$ m$$^{-1}$$ over time. Thus, the time dependence of RF can be divided into two phases, including a rapid decrease for the first two years, followed by a slow decreasing phase. The annual average RF values were also reduced by about half due to decontamination. Furthermore, to investigate the impact of anthropogenic activities on the RF temporal change, the monitoring data were classified into two groups, namely inside and outside the Fukushima evacuation zone. The RF decreased faster in the second than in the first group, which was consistent with the reported data on the time dependence of the air dose rate, suggesting that anthropogenic activities can promote environmental remediation and thereby reduce atmospheric radiocesium content. In addition, the currently observed RF reduction was faster than that reported for the Chernobyl Nuclear Power Plant accident for the same period, consisting with faster environmental remediation at catchment scale in Fukushima compared to Europe.

Access

:

- Accesses

InCites™

:

パーセンタイル:0

分野:Environmental Sciences

Altmetrics

:

[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.