title: Radiocaesium partitioning in Japanese cedar forests following the "early" phase of Fukushima fallout redistribution.
abstract: Our study focused on radiocaesium (137Cs) partitioning in forests, three vegetation periods after the Fukushima Daiichi nuclear power plant accident.137Cs distribution in forest components (organic and mineral soil layers as well as tree compartments: stem, bark, needles, branches and roots) was measured for two Japanese cedar stand ages (17 and 33 years old). The results showed that around 85% of the initial deposit was found in the forest floor and topsoil. For the youngest stand almost 70% of the deposit is present in the forest floor, whereas for the oldest stand 50% is present in the 0-3 cm mineral soil layer. For trees, old and perennial organs (including dead and living needles and branches, litter fall and outer bark) directly exposed to the fallout remained the most contaminated. The crown concentrated 61-69% of the total tree contamination. Surprisingly the dead organs concentrated 25 ± 9% (young cedars) to 36 ± 20% (mature cedar) of the trees' residual activity, highlighting the importance of that specific compartment in the early post-accident phase for Japanese cedar forests. Although the stem (including bark) represents the highest biomass pool, it only concentrates 3.3% and 4.6% of the initial137Cs deposit for mature and young cedars, respectively.
authors.affiliation: Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV, SERIS, L2BT, Cadarache, France.
authors.forename: Frederic
authors.initials: F
authors.lastname: Coppin
authors.affiliation: Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV, SERIS, L2BT, Cadarache, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Hurtevent
authors.affiliation: Center for Research in Isotopes and Environmental Dynamics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Loffredo
authors.affiliation: Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE, SRTG, LT2S, Fontenay-aux-Roses, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Simonucci
authors.affiliation: Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE, SRTG, LT2S, Fontenay-aux-Roses, France.
authors.forename: Anthony
authors.initials: A
authors.lastname: Julien
authors.affiliation: Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV, SESURE, LEREN, Cadarache, France.
authors.forename: Marc-Andre
authors.initials: MA
authors.lastname: Gonze
authors.affiliation: Fukushima University. Institute of Environmental Radioactivity. 1 Kanayagawa, Fukushima City, Fukushima Prefecture, 960-1296, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Nanba
authors.affiliation: Center for Research in Isotopes and Environmental Dynamics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Onda
authors.affiliation: Andra, Research and Development Division, 1-7 rue Jean-Monnet, 92298 Châtenay-Malabry, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Thiry
mesh_terms: D018533:Biomass; D002588:Cesium Radioisotopes / Q000032:analysis*; D032485:Cryptomeria / Q000737:chemistry*; D017753:Ecosystem; D065928:Forests; D062406:Fukushima Nuclear Accident; D011834:Radiation Monitoring; D012987:Soil / Q000737:chemistry; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D013499:Surface Properties
chemical_list: D002588:Cesium Radioisotopes; D012987:Soil; D012990:Soil Pollutants, Radioactive