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

Abstract

Atmospheric aerosols contain particulates that are deposited to oceanic surface waters.These can represent a major source of nutrients, trace metals, and organic compounds for the marine environment. The Japan Sea and the western Pacific Ocean are particularly affected by aerosols due to the transport of desert dust and industrially derived particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) from continental Asia. We hypothesized that supplementing seawater with aerosol particulates would lead to measurable changes in surface water nutrient composition as well as shifts in the marine microbial community. Shipboard experiments in the Pacific Ocean involved the recovery of oligotrophic oceanic surface water and subsequent supplementation with aerosol particulates obtained from the nearby coastal mountains, to simulate marine particulate input in this region. Initial increases in nitrates due to the addition of aerosol particulates were followed by a decrease correlated with the increase in phytoplankton biomass, which was composed largely of Bacillariophyta (diatoms), including Pseudo-nitzschia and Chaetoceros species. This shift was accompanied by changes in the bacterial community, with apparent increases in the relative abundance of heterotrophic Rhodobacteraceae and Colwelliaceae in aerosol particulate treated seawater. Our findings provide empirical evidence revealing the impact of aerosol particulates on oceanic surface water microbiology by alleviating nitrogen limitation in the organisms. 4

Characterization and sources of colored dissolved organic matter in a coral reef ecosystem subject to ultramafic erosion pressure (New Caledonia, Southwest Pacific)

“…This potential contribution in tyrosine 2like sources involves windy conditions (wind b22 nt during the cruise). More investigations of aerosol deposition along the eastern coast of New Caledonia, as recently reported by Maki et al (2016) and Chien et al (2016), could explain the input of organic compounds in this coral reef ecosystems.…”

The Effect of Atmospheric Acid Processing on the Global Deposition of Bioavailable Phosphorus From Dust

“…We see the strongest peak during the Northern Hemisphere spring (March–April–May; Figure S6), which is consistent with the findings of Chen et al (). Maki et al () find that Asian dust is a major nutrient source to the area of the NW Pacific under the plume though their study concentrates on the flux of atmospheric nitrate to this N limited region. As argued below the greatly increased flux of Bio‐P from the dust plume will reduce the potential effect of switching to P limitation and may also increase the N 2 fixation in the surface waters (Jickells & Moore, ) as well as increasing the total primary productivity over longer timescales (Tyrrell, ).…”

Impact of Contrasted Weather Conditions on CDOM Absorption/Fluorescence and Biogeochemistry in the Eastern Lagoon of New Caledonia

“…Atmospheric inputs may result in particles transported by wind from mining extraction sites that are pushed by trades from the South to the North of the ELNC. Atmospheric deposition of particles (Maki et al, 2016) can affect the whole lagoon as aerosols can be transported over long distance in New Caledonia (Lefèvre et al, 2010;Csavina et al, 2012;Pasquet et al, 2018). Aerosols, which are known to be enriched in nutrients, OM and metals, may induce a stimulation of plankton abundances, including those of Synechococcus sp.…”