DOI: 10.1002/2014GB004975
Scopus记录号: 2-s2.0-84939255024
论文题名: Biological and physical controls on N<inf>2</inf>, O<inf>2</inf>, and CO<inf>2</inf> distributions in contrasting Southern Ocean surface waters
作者: Tortell P ; D ; , Bittig H ; C ; , Körtzinger A ; , Jones E ; M ; , Hoppema M
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2015
卷: 29, 期: 7 起始页码: 994
结束页码: 1013
语种: 英语
英文关键词: air-sea flux
; dissolved gases
; net community production
; Southern Ocean
Scopus关键词: air-sea interaction
; biomass
; biophysics
; carbon dioxide
; chlorophyll a
; concentration (composition)
; dissolved gas
; net primary production
; nitrous oxide
; nutrient availability
; phytoplankton
; sea ice
; spatial distribution
; surface water
; Southern Ocean
; Vindula arsinoe
英文摘要: We present measurements of pCO2 , O2 concentration, biological oxygen saturation (ΔO2 /Ar), and N2 saturation (ΔN2 ) in Southern Ocean surface waters during austral summer, 2010-2011. Phytoplankton biomass varied strongly across distinct hydrographic zones, with high chlorophyll a (Chl a) concentrations in regions of frontal mixing and sea ice melt. pCO2 and ΔO2 /Ar exhibited large spatial gradients (range 90 to 450μatm and -10 to 60%, respectively) and covaried strongly with Chl a. However, the ratio of biological O2 accumulation to dissolved inorganic carbon (DIC) drawdown was significantly lower than expected from photosynthetic stoichiometry, reflecting the differential time scales of O2 and CO2 air-sea equilibration. We measured significant oceanic CO2 uptake, with a mean air-sea flux (∼-10mmolm-2d-1) that significantly exceeded regional climatological values. N2 was mostly supersaturated in surface waters (mean ΔN2 of +2.5%), while physical processes resulted in both supersaturation and undersaturation of mixed layer O2 (mean ΔO2phys =2.1%). Box model calculations were able to reproduce much of the spatial variability of ΔN2 and ΔO2phys along the cruise track, demonstrating significant effects of air-sea exchange processes (e.g., atmospheric pressure changes and bubble injection) and mixed layer entrainment on surface gas disequilibria. Net community production (NCP) derived from entrainment-corrected surface ΔO2 /Ar data, ranged from ∼-40 to >300mmolO2 m-2d-1 and showed good coherence with independent NCP estimates based on seasonal mixed layer DIC deficits. Elevated NCP was observed in hydrographic frontal zones and stratified regions of sea ice melt, reflecting physical controls on surface water light fields and nutrient availability. Key Points Biological and physical controls on Southern Ocean gases are quantified Sea-air CO2 fluxes significantly exceed regional climatological values Net community production estimates are corrected for physical processes ©2015. 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/77963
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC, Canada; Department of Botany, University of British Columbia, Vancouver, BC, Canada; Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany; Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Recommended Citation:
Tortell P,D,, Bittig H,et al. Biological and physical controls on N<inf>2</inf>, O<inf>2</inf>, and CO<inf>2</inf> distributions in contrasting Southern Ocean surface waters[J]. Global Biogeochemical Cycles,2015-01-01,29(7)