title: The transfer of radiocesium from the bark to the stemflow of chestnut trees (Castanea crenata) contaminated by radionuclides from the Fukushima Dai-ichi nuclear power plant accident.
abstract: We report on the behavior of radiocesium in tree bark and its transfer into the stemflows of chestnut trees in a forest in the Fukushima Prefecture, Japan. In stems that were present at the time of the accident, the radiocesium concentration of the bark was found to be approximately 10 times that of the wood. The average (137)Cs concentration of the dissolved fraction (<0.45 μm) in the stemflow was measured to be around 10 Bq/L. The (137)Cs concentration ratio [present at the time of the accident (Bq/kg) in the bark/the dissolved fraction in the stemflow (Bq/L)] was approximately 10(3). A strong positive correlation was observed between the radiocesium concentration and the electrical conductivity of the dissolved fraction of the stemflow; this result suggests that radiocesium and electrolytes have the same elution mechanism from the tree. The size fractionation analysis of the <0.45 μm fraction through ultrafiltration revealed that the radiocesium was present as an almost dissolved species. Some of the particles in the particulate fraction (>0.45 μm) of the stemflow were strongly adsorbed radiocesium.
authors.affiliation: Fukushima Environmental Safety Center, Japan Atomic Energy Agency, Sahei 8F, 1-29, Okitama-cho, Fukushima-shi, Fukushima 960-8034 Japan. Electronic address: sasaki.yoshito@jaea.go.jp.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Sasaki
authors.affiliation: Fukushima Environmental Safety Center, Japan Atomic Energy Agency, Sahei 8F, 1-29, Okitama-cho, Fukushima-shi, Fukushima 960-8034 Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Abe
authors.affiliation: Fukushima Environmental Safety Center, Japan Atomic Energy Agency, Sahei 8F, 1-29, Okitama-cho, Fukushima-shi, Fukushima 960-8034 Japan.
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Mitachi
authors.affiliation: Fukushima Environmental Safety Center, Japan Atomic Energy Agency, Sahei 8F, 1-29, Okitama-cho, Fukushima-shi, Fukushima 960-8034 Japan.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Fukushima Environmental Safety Center, Japan Atomic Energy Agency, Sahei 8F, 1-29, Okitama-cho, Fukushima-shi, Fukushima 960-8034 Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ishii
authors.affiliation: Fukushima Environmental Safety Center, Japan Atomic Energy Agency, Sahei 8F, 1-29, Okitama-cho, Fukushima-shi, Fukushima 960-8034 Japan.
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Niizato
mesh_terms: D002588:Cesium Radioisotopes / Q000378:metabolism*; D029962:Fagaceae / Q000378:metabolism*; D062406:Fukushima Nuclear Accident; D007564:Japan; D055848:Nuclear Power Plants; D024301:Plant Bark / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D018547:Plant Stems / Q000378:metabolism*; D011834:Radiation Monitoring; D011848:Radioactive Pollutants / Q000378:metabolism*; D014934:Wood / Q000378:metabolism
chemical_list: D002588:Cesium Radioisotopes; D011848:Radioactive Pollutants
keywords: Cesium; Chestnut; Deciduous broadleaf tree; Fukushima Daiichi; Stemflow