日本地球惑星科学連合2018年大会

講演情報

[EJ] Eveningポスター発表

セッション記号 M (領域外・複数領域) » M-AG 応用地球科学

[M-AG33] 福島原発事故により放出された放射性核種の環境動態

2018年5月20日(日) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:北 和之(茨城大学理学部)、恩田 裕一(筑波大学アイソトープ環境動態研究センター)、篠原 厚(大阪大学、共同)、津旨 大輔(一般財団法人 電力中央研究所)

[MAG33-P06] Radiocesium leaching through stemflow and branchflow from coniferous and deciduous trees following the Fukushima Dai-ichi Nuclear Power Plant accident

*Zul Hilmi Saidin1Yuichi Onda1Hiroaki Kato1 (1.Center for Research on Isotopes and Environmental Dynamics, University of Tsukuba)

キーワード:Radiocesium leaching, Stemflow, Branchflow, Coniferous and deciduous trees , Fukushima Dai-ichi Nuclear Power Plant accident

Fukushima Dai-ichi Nuclear Power Plant accident has released a massive amount of radiocesium into the forest ecosystem in the past 7 years ago. Thus, the initial fallout majorly intercepted and attached to the canopy, especially for evergreen forest such as cedar stands. However, for deciduous broad-leaved forest such as for oak stands, the major exposed were branches and stems since at the time of the accident the leaves had already fallen. Through precipitation events, radiocesium from the canopy has washed out to the branch and then channeled to the trunk via preferential pathways before deposited onto the forest floor time to time. Hence, this radiocesium leaching through stemflow and branchflow demonstrates an important component in the deposition and cycle process of radiocesium. As the deposition flux of radiocesium was enriched by stemflow generation per rainfall event, far less is known on which part of the forest stand, either at the canopy and/or trunk that contributing to this leaching process. Therefore, in this study, we investigated the relationship between radiocesium leaching and stemflow generation of the coniferous forest (young Japanese cedar trees) and mixed deciduous broad-leaved forest (Japanese oak trees). In more details, we also determined the different pathway of radiocesium leaching for branchflow through young and old foliage and for stemflow at the various height of canopy and trunk based on different collector setup.