Vertical distribution and transport of radiocesium via branchflow and stemflow through the canopy of cedar and oak stands in the aftermath of the Fukushima Dai-ichi Nuclear Power Plant accident
Vertical distribution and transport of radiocesium via branchflow and stemflow through the canopy of cedar and oak stands in the aftermath of the Fukushima Dai-ichi Nuclear Power Plant accident
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福岛第一核电站事故后放射性铯通过雪松和橡树冠层的分支流和茎流的垂直分布和运输
DOI：
10.1016/j.scitotenv.2021.151698
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发表时间：
2022
影响因子：
9.8
通讯作者：
Onda Yuichi
中科院分区：
文献类型：
--
作者：
Saidin Zul Hilmi;Levia Delphis F.;Kato Hiroaki;Kurihara Momo;Hudson Janice E.;Nanko Kazuki;Onda Yuichi
为了满足对放射性沉降物影响下的树枝流和树干流经森林的放射性铯传输数据的需要，本研究考察了日本雪松幼树树冠的树枝流和树干流中放射性铯通量的垂直变化。D.Don)和日本橡树(Quercus Serrata Murray)在福岛第一核电站事故后的照片。在福岛第一核电站事故地点西北约40公里处的林区，137Cs浓度在不同采样期和两个森林之间存在显著差异，橡树林的137Cs浓度和沉积通量高于雪松林。以单位树干断面积计算，雪松和栎林产生的~(137)Cs沉积通量分别为375Bq/m和2810Bq/m−2a−1。其中，71%和48%分别来自雪松和栎树冠层，其余分别来自树干。相应地，栎林放射性铯的来源更平衡，近一半的通量来自树冠(48%)，另一半来自树干(52%)。只有大约四分之一(29%)的放射性铯通量来自日本雪松的树干。这项工作的结果提供了必要的数据，使人们能够更彻底地概念化森林中的放射性铯循环。将这些经验结果与实物模型结合起来，可能会导致更好的森林管理和积极主动的战略，以恢复受放射性污染的森林，并降低那些使用森林产品的人的辐射剂量率暴露风险。
Aiming to fill a need for data regarding radiocesium transport via both branchflow and stemflow through forests impacted by radioactive fallout, this study examined the vertical variation of radiocesium flux from branchflow and stemflow through the canopies of young Japanese cedar (Cryptomeria japonica(L. f.) D. Don) and Japanese oak (Quercus serrataMurray) trees in the aftermath of the Fukushima Dai-ichi Nuclear Power Plant accident. In forested areas approximately 40 km northwest of the location of the Fukushima Dai-ichi accident, the137Cs concentration varied significantly among sampling periods and between the two forests, with the oak stand exhibiting higher137Cs concentrations and depositional fluxes than the cedar stand. Expressed per unit trunk basal area, the depositional flux of137Cs generated from the cedar and oak stands was 375 and 2810 Bq m−2year−1, respectively. Of this total, 71% and 48% originated from the cedar and oak canopy, respectively, while the remainder originated from the trunk. Accordingly, the origin of radiocesium was more balanced for the oak stand with almost half of the flux coming from the canopy (48%) and the other half from the trunk (52%). Only about a quarter (29%) of the radiocesium flux originated from the trunk in Japanese cedar. Results from this work provide needed data that can enable a more thorough conceptualization of radiocesium cycling in forests. Coupling these empirical results with a physically-based model would likely lead to better forest management and proactive strategies for rehabilitating radioactively-contaminated forests and reducing the exposure risk of radiation dose rate for those that utilize forest products.