検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年

河川-沿岸における粒子態放射性セシウムの形態に関する研究

Dynamics of particulate radiocaesium in river and coastal area in Fukushima Prefecture

青野 辰雄*; 中西 貴宏   

Aono, Tatsuo*; Nakanishi, Takahiro

帰還困難区域の森林流域の猿田川と合流する高瀬川において、河川水中の放射性セシウム濃度について調査を行った。猿田川では、溶存態放射性セシウム-137濃度の範囲は20-200mBq/Lであった。本流よりも支流から流入する沢水では300mBq/Lを超え、また下流に向かって、溶存態放射性セシウム濃度が増加する傾向にあった。粒子態放射性セシウム-137濃度範囲は、10-400mBq/Lであった。2019年10月の台風等に伴う大雨により河川は増水し、土砂の流入に伴い地形も大きく変化した。出水後に河川中のSS濃度が高くなった傾向はあったが、粒子態放射性セシウム-137濃度に変化は認められなかった。一方で溶存態放射性セシウム-137濃度が大雨以前よりも約50%低下した。大雨による土砂流出に伴い、森林流域の状態が変化したものと考えられる。

In order to elucidate the distribution, behavior and runoff process of radiocaesium in stream water collected from forest catchments, the activity concentrations of dissolved and particulate radiocaesium were monitored in this area. Although there is a very strong correlation between annual mean activity concentration of dissolved Cs-137 and mean air does rate in catchment area, no features were found with activity concentrations of particulate Cs-137 and mean air does rate in the area. The river water increased due to heavy rains caused by two typhoons in October 2019, and then the topography changed drastically with the inflow of sediment. The radioactivity concentrations of dissolved Cs-137 were decreased by about 50% compared to before the heavy rain. However, the change of radioactivity concentrations of particulate Cs-137 have not been observed. It is considered that the condition of the forest basin has changed as one of reasons.

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.