Atmospheric aerosol deposition influences marine microbial communities in oligotrophic seawaters of the western Pacific Ocean

2017 Fiscal Year Final Research Report

• Project/Area Number: 26340049
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental impact assessment
• Research Institution: Kanazawa University
• Principal Investigator: Maki Teruya 金沢大学, 物質化学系, 准教授 (70345601)
• Co-Investigator(Kenkyū-buntansha): 石川 輝 三重大学, 生物資源学研究科, 教授 (00273350) ; 青木 一真 富山大学, 大学院理工学研究部(理学), 教授 (90345546)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: エアロゾル / 貧栄養海域 / 植物プランクトン / 炭酸固定 / 大気沈着 / 海洋細菌

Outline of Final Research Achievements

Atmospheric aerosols, such as desert dust and polluted particulate matter (PM2.5), are transported from continental Asia to surface seawaters of the western Pacific Ocean, and provide a major source of nutrients and trace metals to the marine environments. Supplementing seawater with aerosols possibly change in seawater nutrient composition as well as the marine microbial community. Shipboard experiments in the Pacific Ocean involved the recovery of oligotrophic oceanic water by supplementation with aerosol particulates obtained from the snow-cover mountain. Initial increases in nitrates due to the aerosol addition were followed by a decrease correlated with the phytoplankton (diatoms) increase. The bacterial community also changed with apparent increases in the rates of heterotrophic bacteria in aerosol addition seawater. Our findings provide empirical evidence revealing the aerosol impact on oceanic seawater microbiology by alleviating nitrogen limitation in the organisms.

Free Research Field

微生物生態学