Low 137Cs retention capability of organic layers in Japanese forest ecosystems affected by the Fukushima nuclear accident

  • Jun KoarashiEmail author
  • Mariko Atarashi-Andoh


Quantitative understanding of 137Cs retention behavior in organic layers in Japanese forest ecosystems is of primary importance in the assessment of long-term radioecological impacts of the Fukushima nuclear accident. Litter samples were collected at five forest sites in Fukushima in 2011, 2015, and 2017, and separated into eight fractions with different precursor species and degrees of degradation; afterward, 137Cs inventory was determined. All fractions exhibited a significant decrease in 137Cs inventory over the six-year period. The results suggested that the organic layers in Japanese forest ecosystems have a low 137Cs retention capability, although it differs depending on the forest type.


Radiocesium (137Cs and 134Cs) Fukushima Daiichi nuclear power plant accident Japanese forest ecosystems Organic layers Litter fractionation Ecological half-lives 



The authors thank the Fukushima City Office for advice on selecting the study sites. The authors also thank T. Matsunaga of the Japan Atomic Energy Agency (JAEA) and T. Sato of Hokkaido University for support with the fieldwork, and M. Ishihara, M. Kaminaga, M. Toyoshima, K. Yoshigaki, K. Muto, E. Takeuchi, S. Nishimura, and S. Otosaka of JAEA for support with the laboratory work. This study was partly funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Nuclear Science and Engineering CenterJapan Atomic Energy AgencyIbarakiJapan

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