Krom, MD, Shi, Z, Stockdale, A orcid.org/0000-0002-1603-0103 et al. (12 more authors) (2016) Response of the Eastern Mediterranean Microbial Ecosystem to Dust and Dust Affected by Acid Processing in the Atmosphere. Frontiers in Marine Science, 3. 133. ISSN 2296-7745
Abstract
Acid processes in the atmosphere, particularly those caused by anthropogenic acid gases, increase the amount of bioavailable P in dust and hence are predicted to increase microbial biomass and primary productivity when supplied to oceanic surface waters. This is likely to be particularly important in the Eastern Mediterranean Sea (EMS), which is P limited during the winter bloom and N&P co-limited for phytoplankton in summer. However, it is not clear how the acid processes acting on Saharan dust will affect the microbial biomass and primary productivity in the EMS. Here, we carried out bioassay manipulations on EMS surface water on which Saharan dust was added as dust (Z), acid treated dust (ZA), dust plus excess N (ZN), and acid treated dust with excess N (ZNA) during springtime (May 2012) and measured bacterioplankton biomass, metabolic, and other relevant chemical and biological parameters. We show that acid treatment of Saharan dust increased the amount of bioavailable P supplied by a factor of ~40 compared to non-acidified dust (18.4 vs. 0.45 nmoles P mg−1 dust, respectively). The increase in chlorophyll, primary, and bacterial productivity for treatments Z and ZA were controlled by the amount of N added with the dust while those for treatments ZN and ZNA (in which excessive N was added) were controlled by the amount of P added. These results confirm that the surface waters were N&P co-limited for phytoplankton during springtime. However, total chlorophyll and primary productivity in the acid treated dust additions (ZA and ZNA) were less than predicted from that calculated from the amount of the potentially limiting nutrient added. This biological inhibition was interpreted as being due to labile trace metals being added with the acidified dust. A probable cause for this biological inhibition was the addition of dissolved Al, which forms potentially toxic Al nanoparticles when added to seawater. Thus, the effect of anthropogenic acid processes in the atmosphere, while increasing the flux of bioavailable P from dust to the surface ocean, may also add toxic trace metals such as Al, which moderate the fertilizing effect of the added nutrients.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2016 Krom, Shi, Stockdale, Berman-Frank, Giannakourou, Herut, Lagaria, Papageorgiou, Pitta, Psarra, Rahav, Scoullos, Stathopoulou, Tsiola and Tsagaraki. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Earth Surface Science Institute (ESSI) (Leeds) |
Funding Information: | Funder Grant number Leverhulme Trust RPG-406 |
Depositing User: | Symplectic Publications |
Date Deposited: | 02 Sep 2016 12:07 |
Last Modified: | 05 Oct 2017 16:11 |
Published Version: | http://dx.doi.org/10.3389/fmars.2016.00133 |
Status: | Published |
Publisher: | Frontiers Media |
Identification Number: | 10.3389/fmars.2016.00133 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:104274 |