Evaluation of radiocesium concentrations in new leaves of wild plants two years after the Fukushima Dai-ichi Nuclear Power Plant accident.
Radiocesium ((137)Cs) transfer to plants immediately after the Fukushima Dai-ichi Nuclear Power Plant accident was investigated by collecting newly emerged leaf and soil samples between May 2011 and November 2012 from 20 sites in the Fukushima prefecture. Radiocesium concentrations in leaf and soil samples were measured to calculate concentration ratios (CR). Woody plants exhibited high CR values because (137)Cs deposited on stems and/or leaves were transferred to newly emerging tissues. The CR values in 2012 declined as compared to that in 2011. Exchangeable (137)Cs rates in soil (extraction rate) samples were measured at five sites. These rates decreased at four sites in 2012 and depended on environmental conditions and soil type. Both CR values and extraction rates decreased in 2012. However, CR values reflected the changes in extraction rates and characteristics of each species. Amaranthaceae, Chenopodiaceae, and Polygonaceae, which had been identified as Cs accumulators, presented no clear (137)Cs accumulation ability. In 2012, the perennial plant Houttuynia cordata and deciduous trees Chengiopanax sciadophylloides and Acer crataegifolium displayed high CR values, indicating that these species are (137)Cs accumulators and may be considered as potential species for phytoremediation.
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan. Electronic address: sugiura.yuki@b.mbox.nagoya-u.ac.jp.
Yuki
Y
Sugiura
Radioisotope Research Center, Nagoya University, Nagoya, Aichi 464-8602, Japan. Electronic address: i45329a@nucc.cc.nagoya-u.ac.jp.
Michihiro
M
Shibata
Graduate School of Medicine, Nagoya University, Nagoya, Aichi 466-8550, Japan. Electronic address: ogata.yoshimune@b.mbox.nagoya-u.ac.jp.
Yoshimune
Y
Ogata
Fukushima Prefectural Forestry Research Centre, Koriyama, Fukushima 963-0112, Japan. Electronic address: ozawa_hajime_01@pref.fukushima.lg.jp.
Hajime
H
Ozawa
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan. Electronic address: kanasashi.tsutomu@g.mbox.nagoya-u.ac.jp.
Tsutomu
T
Kanasashi
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan. Electronic address: chisato@agr.nagoya-u.ac.jp.
Chisato
C
Takenaka
D002588:Cesium Radioisotopes / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D007564:Japan; D019684:Magnoliopsida / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D011834:Radiation Monitoring; D012990:Soil Pollutants, Radioactive / Q000032:analysis*
D002588:Cesium Radioisotopes; D012990:Soil Pollutants, Radioactive
Concentration ratio; Exchangeable radiocesium; Fukushima Dai-ichi Nuclear Power Plant accident; Radiocesium; Species specific accumulation