Estimation of radioactive 137-cesium transportation by litterfall, stemflow and throughfall in the forests of Fukushima.
Since the Fukushima Dai-ichi Nuclear Power Plant accident in March 2011, large areas of the forests around Fukushima have become highly contaminated by radioactive nuclides. To predict the future dynamics of radioactive cesium ((137)Cs) in the forest catchment, it is important to measure each component of its movement within the forest. Two years after the accident, we estimated the annual transportation of (137)Cs from the forest canopy to the floor by litterfall, throughfall and stemflow. Seasonal variations in (137)Cs transportation and differences between forests types were also determined. The total amount of (137)Cs transported from the canopy to the floor in two deciduous and cedar plantation forests ranged between 3.9 and 11.0 kBq m(-2) year(-1). We also observed that (137)Cs transportation with litterfall increased in the defoliation period, simply because of the increased amount of litterfall. (137)Cs transportation with throughfall and stemflow increased in the rainy season, and (137)Cs flux by litterfall was higher in cedar plantation compared with that of mixed deciduous forest, while the opposite result was obtained for stemflow.
Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan. Electronic address: izok@fr.a.u-tokyo.ac.jp.
Izuki
I
Endo
Graduate School of Informatics, Kyoto University, 36-1 Hon-cho, Yoshida Sakyo-ku, Kyoto, 606-8501, Japan.
Nobuhito
N
Ohte
Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
Kohei
K
Iseda
Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
Keitaro
K
Tanoi
Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
Atsushi
A
Hirose
Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
Natsuko I
NI
Kobayashi
Department of Biology, Faculty of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba City, 263-8522, Japan.
Masashi
M
Murakami
Field Science Education and Research Center, Kyoto University, Ashiu Forest Research Station, Ashiu, Miyama-cho, Nantan City, Kyoto, 601-0703, Japan.
Naoko
N
Tokuchi
School of Human Science and Environment, University of Hyogo, 1-1-12 Shinzaike-honcho, Himeji City, Hyogo, 670-0092, Japan.
Mizue
M
Ohashi
D002588:Cesium Radioisotopes / Q000032:analysis*; D065928:Forests; D062406:Fukushima Nuclear Accident; D007564:Japan; D018515:Plant Leaves / Q000378:metabolism; D018547:Plant Stems / Q000378:metabolism; D011834:Radiation Monitoring; D011891:Rain; D012621:Seasons; D012990:Soil Pollutants, Radioactive / Q000032:analysis*
D002588:Cesium Radioisotopes; D012990:Soil Pollutants, Radioactive
Annual flux; Cedar plantation; Deciduous–pine mixed forest; Radioactive cesium