AN ESTIMATION OF MICROPLASTICS SEDIMENTATION FLAX IN BEPPU BAY

• MASUMOTO Issei

  愛媛大学大学院 理工学研究科

• KUWAE Michinobu

  愛媛大学沿岸環境科学研究センター

• HINATA Hirohumi

  愛媛大学大学院理工学研究科・愛媛大学沿岸環境科学研究センター 理工学研究科

Bibliographic Information

Other Title

• 別府湾におけるマイクロプラスチックの堆積フラックス
• ベップワン ニ オケル マイクロプラスチック ノ タイセキ フラックス

Abstract

 Plastics production are increasing year by year. In 2010, it is estimated that plastics of 4.8-12.7 million tons flowed out into the ocean. The plastics weathers by heat and UV light, and fragmented into small pieces. The plastic particles of the 0.3-5mm in size are called microplastics. Because microplastics is small, it is easy to be incorporated into the ecosystem and there is concern about bad influence on ecosystem. Recent studies have found that microplastics sink to the bottom of the ocean. However, It has not been clear how much volume is settling down. In this study, the sedimentation flux of microplastics was estimated. We collected and analyzed the sediment cores sampled from the bottom of Beppu Bay. Beppu Bay is suitable for the core sampling, because sediments have not been vertically mixed. Five sediment core samples were taken using Gravity Corer. Four sediment cores were for microplastic analysis, and one was for dating sediment layers. Microplastics extracted from the sediment core samples were analyzed by FT-IR to determine the polymer type. The sedimentary age was determined using the Pb-210 method. A total of 142 pieces of microplastic were detected from four sediment samples. Representative polymer types of the extracted microplastics were polystyrene (PS), polyester (PE), polypropylene (PP). The most common polymer type among plastics is PE which accounted for 55% of the total. From this result, the average sedimentary flux from 1998 to 2017 was calculated as 217 [pieces/m²·y)]. For the case of estimating sedimentary flux of microplastics, this research is the first as far as the authors know. However, since the number of samples is small and variation among samples is large, additional investigation is planned in the future.

Journal

• Journal of Japan Society of Civil Engineers, Ser. B2 (Coastal Engineering)

  Journal of Japan Society of Civil Engineers, Ser. B2 (Coastal Engineering) 74 (2), I_1321-I_1326, 2018

  Japan Society of Civil Engineers

Keywords

• flux of microplastics
• sediment core samples
• Beppu Bay
• ²¹⁰Pb dating

Details

• CRID: 1390564238040996224
• NII Article ID: 40021715486
• NII Article ID: 130007503906
• DOI: 10.2208/kaigan.74.i_1321
• ISSN: 18838944
• ISSN: 18842399
• NDL BIB ID: 029327705
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I029327705
• Web Site: https://www.jstage.jst.go.jp/article/kaigan/74/2/74_I_1321/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed