Elucidation of the process of vertical transport of microplastics via marine biological interaction

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K12307
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 63010:Environmental dynamic analysis-related
• Research Institution: The University of Tokyo
• Principal Investigator: YAMASHITA Rei 東京大学, 大気海洋研究所, 特任研究員 (60599629)
• Co-Investigator(Kenkyū-buntansha): 福田 秀樹 東京大学, 大気海洋研究所, 准教授 (30451892) ; 西部 裕一郎 東京大学, 大気海洋研究所, 准教授 (50403861)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: マイクロプラスチック / 海洋汚染 / セジメントトラップ / ゲルトラップ / 顕微FTIR

Outline of Final Research Achievements

To investigate the dynamics of microplastics (hereafter referred to as MPs) in the ocean, we analyzed the amount of MPs and the type of polymer from the ocean surface, water column, seafloor sediment, and marine organisms using micro FTIR. Under microscopic observation, two MPs could be detected in the gel traps, indicating that MPs were settling on their own. Due to the short mooring time of the trap and the large number of sedimentation particles, it was not possible to collect enough MPs with this method. The sedimentation of MPs from the sediment trap samples tended to be higher in July and lower in March. This result was similar to that of the sedimentation of organic matter and partially elucidated the vertical transport via biological action.

Free Research Field

複合

Academic Significance and Societal Importance of the Research Achievements

海洋環境へ排出されたMPsは回収が困難であることから、正確な現状把握や影響予測、　被害の拡大防止が急務である。本研究ではこれまで検出が難しかった試料からMPsを分析・検出することが可能になったことで海洋生態系におけるMPsの正確な現存量やMPsの挙動の一端を明らかにした。本研究成果から、具体的な政策に結び付けるための根拠といえる実態を提示することができた。