Sediment-Associated Radiocesium Originated from Fukushima Daiichi Nuclear Power Plant Flowing from Ohori River to Lake Teganuma
Sediment-Associated Radiocesium Originated from Fukushima Daiichi Nuclear Power Plant Flowing from Ohori River to Lake Teganuma
复制标题
DOI：
10.2965/jwet.2015.249
复制
发表时间：
2015-01-01
影响因子：
--
通讯作者：
Onda, Yuichi
中科院分区：
文献类型：
--
作者：
Koibuchi, Yukio;Murakami, Michio;Onda, Yuichi
放射性铯在福岛第一核电站（FDNPP）事故后沉积并附着在内陆土壤中。土壤通过大堀川流入手沼湖。2011年10月至2014年3月期间，对Teganuma湖和Ohori河周围沉积物中的放射性铯进行了实地观测，以量化放射性铯。我们对输往大堀江的沉积物进行了定量，发现2012年大堀江中的放射性铯总储量为2,190 MBq，主要附着在粉砂的细粒沉积物上。放射性铯作为悬浮沉积物在大堀河流域迁移，约占2 TBq总沉降物的10%。2012年大堀川放射性铯的总通量为3，800 MBq，2013年减少到6.65 MBq。这些结果表明，大部分放射性铯污染的沉积物在2011年向下游迁移，并在2012年后急剧减少。在阿武熊川进行类似的研究时，只计算出总沉降物的1%，表明迁移是阿武熊川的10倍。这是由于与Abukuma盆地相比，Teganuma盆地的城市化，因此在较短的时间内运输了更多的铯。
Radiocesium has been deposited after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident and affix to the soils inland. The soils flowed into Lake Teganuma through Ohori River. Field observation was carried out to quantify radiocesium, associated with sediments, transported around Lake Teganuma and Ohori River from October 2011 to March 2014. We quantified the sediment transported to Ohori River and found that the total radiocesium stock in Ohori River was 2,190 MBq which was mostly attached to the fine-grained sediment of silt in 2012. The radiocesium, transported as a suspended sediment in the Ohori River watershed, was approximately 10 percent of the total fallout of 2 TBq. The total flux of radiocesium in Ohori River were 3,800 MBq in 2012 and reduced to 6.65 MBq in 2013. These results denote that most of the radiocesium-polluted sediments were transported downstream in 2011 and sharply decreased after 2012. When a similar study was conducted in Abukuma River, only 1% of the total fallout was calculated indicating transport was 10 times that of the Abukuma River. This is attributed to be urbanization of Teganuma basin in comparison to the Abukuma basin, thus more cesium were transported in a shorter time period.