A key uncertainty for predicting future ocean oxygen levels is the response and feedback of organic matter respiration demand. One poorly constrained component of the respiration demand is the oxygen‐to‐carbon remineralization ratio—the respiration quotient. Currently, multiple biological hypotheses can explain variation in the respiration quotient of organic matter produced in the surface ocean. To test these hypotheses, we directly quantified the particulate respiration quotient in 715 samples along a meridional section of the Atlantic Ocean and compared to previous Pacific Ocean observations. We demonstrate significant regional shifts in the respiration quotient and a two‐basin average of 1.16. Possible diel oscillations were also observed in the respiration quotient. Basin and regional variation in the respiration quotient were positively linked to temperature, N versus P stress, and plankton size structure. These observations suggest a complex regulation of the respiration quotient with important implications for the regional coupling of carbon and oxygen cycling.
Climate warming likely drives ocean deoxygenation, but models still cannot fully explain observed declines in oxygen. One unconstrained parameter is the oxygen demand per carbon respired for complete remineralization of organic matter (i.e., the total respiration quotient,
- PAR ID:
- 10476393
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Global Biogeochemical Cycles
- Volume:
- 37
- Issue:
- 12
- ISSN:
- 0886-6236
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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