ORCID iD
Yuan Shen: http://orcid.org/0000-0001-6618-4226
Ronald Benner: https://orcid.org/0000-0002-1238-2777
Document Type
Article
Abstract
A large quantity of reduced carbon is sequestered in the ocean as refractory dissolved molecules that persist through several circuits of global overturning circulation. Key aspects of the cycling of refractory dissolved organic carbon (DOC) remain unknown, making it challenging to predict how this large carbon reservoir will respond to climate change. Herein we investigate mechanisms that remove refractory DOC using bioassay experiments with DOC isolated from surface, mesopelagic and deep waters of the Atlantic Ocean. The isolated DOC was refractory to degradation by native microbial communities, even at elevated concentrations. However, when the refractory DOC was introduced to a series of novel environmental conditions, including addition of a labile substrate, a microbial community from coastal waters and exposure to solar radiation, a substantial fraction (7–13%) was removed within 1.5 years. Our results suggest that while refractory molecules can persist in the ocean for millennia, removal is rapid when they encounter their fate. The observed and projected climate-induced slowdown of global overturning circulation could reduce the exposure of refractory molecules to disparate removal processes. Assuming a constant rate of production, the reservoir size of refractory DOC could increase as overturning circulation slows, providing a negative feedback to rising atmospheric CO2.
Digital Object Identifier (DOI)
https://doi.org/10.1038/s41598-018-20857-5
Publication Info
Published in Scientific Reports, Volume 8, Issue 1, 2018.
APA Citation
Shen, Y., & Benner, R. (2018). Mixing It up in the Ocean Carbon Cycle and the Removal of Refractory Dissolved Organic Carbon. Scientific Reports, 8(1). https://doi.org/10.1038/s41598-018-20857-5
Rights
© the author(s), 2018.
This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Te images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.