放射性从树冠到森林地板的动态,由福岛森林的主要沉积过程在准平衡状态下进行
Wataru Sakashita1, Naohiro Imamura2, Tamotsu Sato3
1Center for Forest Restoration and Radioecology, Forestry and Forest Products Research Institute (FFPRI), 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan; Department of Forest Soils, FFPRI, 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan.
Journal of environmental radioactivity
|March 9, 2025
概括
从森林树冠到地面的放射性 (137Cs) 转移每年不到2%. 垃圾降落是主要的途径,特别是在日本香柏树林中,有助于长期137Cs分布预测.
科学领域:
- 环境科学 环境科学
- 森林生态 森林生态
- 放射化学 放射化学是指辐射化学.
背景情况:
- 精确测量放射 (137Cs) 转移对于预测其森林分布至关重要.
- 了解树冠到森林的地面流动是准平衡森林生态系统的关键.
研究的目的:
- 量化137Cs在日本香柏树和树叶树林中通过落,茎流和垃圾落的流量.
- 确定每个过程在准平衡时对总137Cs转移的贡献.
- 将这些流量解释为土壤中137Cs根部吸收的指标.
主要方法:
- 在福岛县的三个森林类型 (137Cs流量) 的现场测量 (两个日本香柏树,一个叶大叶树).
- 从2020年到2023年收集数据.
- 分析137Cs在落,干流和垃圾落之间进行分区.
主要成果:
- 每年的137Cs从树冠到森林地板的转移始终低于初始沉积量的2%.
- 垃圾降落是占主导地位的途径,在所有森林类型中超过137Cs总转移的50%.
- 在日本的雪松树林中,137Cs通过垃圾流量的比例显著高 (74-92%),而不是落叶森林 (57-60%).
结论:
- 在准平衡状态下测量到的树冠到地板137Cs转移率可以作为根部吸收的代理值.
- 垃圾在这些森林生态系统中的137Cs动态中发挥着关键作用.
- 这些发现提高了森林中长期137Cs分布和活动度预测的准确性.
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