DOI: 10.1002/2016GB005567
Scopus记录号: 2-s2.0-85018586061
论文题名: N2O production and consumption from stable isotopic and concentration data in the Peruvian coastal upwelling system
作者: Bourbonnais A ; , Letscher R ; T ; , Bange H ; W ; , Échevin V ; , Larkum J ; , Mohn J ; , Yoshida N ; , Altabet M ; A
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2017
卷: 31, 期: 4 起始页码: 678
结束页码: 698
语种: 英语
英文关键词: coastal Peru
; Eastern Tropical South Pacific
; isotopomers
; nitrous oxide
; oxygen deficient zone
; stable isotopes
Scopus关键词: biogeochemical cycle
; coastal zone
; concentration (composition)
; denitrification
; isotopic composition
; marine environment
; nitrous oxide
; organic matter
; oxic conditions
; oxygen minimum layer
; stable isotope
; surface water
; Pacific Ocean
; Pacific Ocean (East)
; Pacific Ocean (Tropical)
; Peru
英文摘要: The ocean is an important source of nitrous oxide (N2O) to the atmosphere, yet the factors controlling N2O production and consumption in oceanic environments are still not understood nor constrained. We measured N2O concentrations and isotopomer ratios, as well as O2, nutrient and biogenic N2 concentrations, and the isotopic compositions of nitrate and nitrite at several coastal stations during two cruises off the Peru coast (~5–16°S, 75–81°W) in December 2012 and January 2013. N2O concentrations varied from below equilibrium values in the oxygen deficient zone (ODZ) to up to 190 nmol L−1 in surface waters. We used a 3-D-reaction-advection-diffusion model to evaluate the rates and modes of N2O production in oxic waters and rates of N2O consumption versus production by denitrification in the ODZ. Intramolecular site preference in N2O isotopomer was relatively low in surface waters (generally −3 to 14‰) and together with modeling results, confirmed the dominance of nitrifier-denitrification or incomplete denitrifier-denitrification, corresponding to an efflux of up to 0.6 Tg N yr−1 off the Peru coast. Other evidence, e.g., the absence of a relationship between ΔN2O and apparent O2 utilization and significant relationships between nitrate, a substrate during denitrification, and N2O isotopes, suggest that N2O production by incomplete denitrification or nitrifier-denitrification decoupled from aerobic organic matter remineralization are likely pathways for extreme N2O accumulation in newly upwelled surface waters. We observed imbalances between N2O production and consumption in the ODZ, with the modeled proportion of N2O consumption relative to production generally increasing with biogenic N2. However, N2O production appeared to occur even where there was high N loss at the shallowest stations. ©2017. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/77751
Appears in Collections: 气候变化事实与影响
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作者单位: School for Marine Science and Technology, University of Massachusetts Dartmouth, New Bedford, MA, United States; Earth System Science, University of California, Irvine, CA, United States; GEOMAR, Helmholtz Centre for Ocean Research Kiel, Kiel, Germany; LOCEAN/IRD/IPSL, Laboratoire d'Océanographie et de Climatologie: Expérimentation et Approches Numériques, Paris, France; Empa, Laboratory for Air Pollution and Environmental Technology, Dübendorf, Switzerland; Department of Chemical Science and Engineering, Tokyo Institute of Technology, Yokohama, Japan; Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
Recommended Citation:
Bourbonnais A,, Letscher R,T,et al. N2O production and consumption from stable isotopic and concentration data in the Peruvian coastal upwelling system[J]. Global Biogeochemical Cycles,2017-01-01,31(4)