Skip to main content

The inhibition of N2O production by ocean acidification in cold temperate and polar waters

Author(s): Rees, Andrew P; Brown, Ian J; Jayakumar, Amal; Ward, Bess B

To refer to this page use:
Abstract: The effects of ocean acidification (OA) on nitrous oxide (N2O) production and on the community composition of ammonium oxidizing archaea (AOA) were examined in the northern and southern sub-polar and polar Atlantic Ocean. Two research cruises were performed during June 2012 between the North Sea and Arctic Greenland and Barent Seas, and in January–February 2013 to the Antarctic Scotia Sea. Seven stations were occupied in all during which shipboard experimental manipulations of the carbonate chemistry were performed through additions of NaHCO3−+HCl in order to examine the impact of short-term (48 h for N2O and between 96 and 168 h for AOA) exposure to control and elevated conditions of OA. During each experiment, triplicate incubations were performed at ambient conditions and at 3 lowered levels of pH which varied between 0.06 and 0.4 units according to the total scale and which were targeted at CO2 partial pressures of ~500, 750 and 1000 µatm. The AOA assemblage in both Arctic and Antarctic regions was dominated by two major archetypes that represent the marine AOA clades most often detected in seawater. There were no significant changes in AOA assemblage composition between the beginning and end of the incubation experiments. N2O production was sensitive to decreasing pHT at all stations and decreased by between 2.4% and 44% with reduced pHT values of between 0.06 and 0.4. The reduction in N2O yield from nitrification was directly related to a decrease of between 28% and 67% in available NH3 as a result of the pH driven shift in the NH3:NH4+ equilibrium. The maximum reduction in N2O production at conditions projected for the end of the 21st century was estimated to be 0.82 Tg N y−1.
Publication Date: May-2016
Electronic Publication Date: 17-Dec-2015
Citation: Rees, Andrew P., Ian J. Brown, Amal Jayakumar, and Bess B. Ward. "The inhibition of N2O production by ocean acidification in cold temperate and polar waters." Deep Sea Research Part II: Topical Studies in Oceanography 127 (2016): 93-101. doi:10.1016/j.dsr2.2015.12.006.
DOI: doi:10.1016/j.dsr2.2015.12.006
ISSN: 0967-0645
Pages: 93 - 101
Type of Material: Journal Article
Journal/Proceeding Title: Deep-Sea Research Part II: Topical Studies in Oceanography
Version: Final published version. This is an open access article.

Items in OAR@Princeton are protected by copyright, with all rights reserved, unless otherwise indicated.