検索対象:     
報告書番号:
※ 半角英数字
 年 ~  年

Forest type effects on the retention of radiocesium in organic layers of forest ecosystems affected by the Fukushima nuclear accident

福島第一原子力発電所事故の影響を受けた森林生態系の有機層における放射性セシウム保持に及ぼす森林タイプの影響

小嵐 淳; 安藤 麻里子; 松永 武; 眞田 幸尚

Koarashi, Jun; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sanada, Yukihisa

森林表面の有機層による放射性セシウムの保持が森林生態系内の放射性セシウムの動態において重要な役割を果たすが、日本の森林生態系において森林タイプが有機層による放射性セシウムの保持能力やそのプロセスに及ぼす影響はよくわかっていない。本研究では、福島原子力発電所事故の影響を受けた福島市内のタイプの異なる森林において、有機層が放射性セシウムをどれだけ、どのように保持しているかを調査した。その結果、落葉広葉樹林と比較して、針葉樹林の有機層によるセシウム保持能力が高く、その保持能力は樹木フェノロジーとリター分解プロセスの違いによって説明できることが示された。

Forest-floor organic layers play a key role in controlling the overall bioavailability of $$^{137}$$Cs in forest ecosystems; however, there is still an insufficient understanding of how forest types influence the retention capability of $$^{137}$$Cs in organic layers in Japanese forest ecosystems. Here we conducted plot-scale investigations on the retention of $$^{137}$$Cs in organic layers at two contrasting forest sites in Fukushima. In a deciduous broad-leaved forest, approximately 80% of the deposited $$^{137}$$Cs migrated to mineral soil located below the organic layers within two years after the accident, with an ecological half-life of approximately one year. Conversely, in an evergreen coniferous forest, more than half of the deposited $$^{137}$$Cs remained in the organic layers, with an ecological half-life of 2.1 years. The observed retention behavior can be well explained by the tree phenology and accumulation of $$^{137}$$Cs associated with litter materials with different degrees of degradation in the organic layers.

Access

:

- Accesses

InCites™

:

Altmetrics

:

[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.