2023-08-24 ロードアイランド大学(URI)
◆マイクロプラスチックのほとんどは、バッグやボトルなどの使い捨てプラスチックから発生し、最終的に海洋堆積物に堆積して、海水浴客や海洋生物に害を与える。湾はプラスチック汚染のフィルターとして機能しており、堆積物を浄化する努力によって海への影響を減らすことができるかもしれない。
◆研究者たちは、ロードアイランド州がプラスチックの使用を最小限に抑え、この問題に率先して取り組むことを願っている。
＜関連情報＞
- https://www.uri.edu/news/2023/08/new-uri-study-finds-extensive-microplastics-in-narragansett-bay/
- https://www.nature.com/articles/s41598-023-36228-8
都市から海へ、プラスチックの広範な河口堆積物貯蔵： 米国ロードアイランド州ナラガンセット湾 Extensive estuarine sedimentary storage of plastics from city to sea: Narragansett Bay, Rhode Island, USA
Victoria M. Fulfer & J. P. Walsh
Scientific Reports Published:23 June 2023
DOI:https://doi.org/10.1038/s41598-023-36228-8
Abstract
Plastics are an important new component of the global sedimentary system, and much concern exists about their transport, fate and impact. This study presents the first system-scale assessment of sedimentary storage of microplastic for an estuary, Narragansett Bay, RI (USA), and the measurements of shoreline and seabed sediments add to the growing body of literature demonstrating high coastal concentrations. Microplastic concentrations in sediments ranged from 396 to over 13,000 MP particles kg−1 dry sediment (DW), comparable to other shoreline and seafloor sites located near urban centers. As previously reported for fine sediment and other pollutants, estuarine plastic storage is extensive in Narragansett Bay, especially within the upper urbanized reaches. Over 16 trillion pieces of plastic weighing near 1000 tonnes is calculated to be stored in surface sediments of the Bay based on a power-law fit. This work highlights that estuaries may serve as a significant filter for plastic pollution, and this trapping may have negative consequences for these valuable, productive ecosystems but offer potential for efficient removal.
