Distribution and source identification of Pu in the tidal flat wetlands of northern Jiangsu Province and radial sand ridge of southern Yellow Sea-An explanation of “land-sea interaction”

• Published in: Catena (Giessen) 2021-11, Vol.206, p.105506, Article 105506
• Main Authors: Wang, Ruirui, Zhu, Yawei, Hu, Feifei, Xu, Xinyue, Sun, Zhuyou, Liu, Zhiyong
• Format: Article
• Language: English
• Subjects: 239+240Pu activity; 240Pu/239Pu atom ratio; Global fallout; Land-sea interaction; Pacific proving grounds
• ISSN: 0341-8162; 1872-6887
• DOI: 10.1016/j.catena.2021.105506

•The contribution of Pu from PPG close-in fallout in some samples is 41.5–50%.•Pu from the ocean to the coast is mainly controlled by ocean currents and tides.•The migration of Pu can be explained by the idea of “source-sink”.•The distribution of Pu in coastal areas reflects the “land-sea interaction”. 239Pu, 240Pu in the surface sediments from tidal flat wetlands in northern Jiangsu Province and radial sand ridge in southern Yellow Sea were analyzed by SF-ICP-MS. Tidal flat wetlands and radial sand ridge are the special sediment deposits in coastal area, which are the ideal places to study “land-sea interaction”. The 240Pu/239Pu atom ratios in our research samples show that the Pu in most samples is from global fallout, only the Pu in a few samples near Yangtze River Estuary and channel of radial sand ridge is affected by the close-in Pu fallout from Pacific Proving Grounds (PPG), and the contribution of Pu from PPG is 41.5–50%. In composition, since the study samples are mainly sand, the 239+240Pu activities in our samples are lower than those in river sediments of China. The transport of Pu is a very important scientific issue, and researches have shown that Pu is “transported” into the coastal areas and seas from the land- based “source”. In addition, the Pu distribution in coastal areas and seas is affected by the input of rivers and ocean currents, which is a manifestation of the “land-sea interaction”.