DOI: 10.1002/gbc.20063
Scopus记录号: 2-s2.0-84881528478
论文题名: Evidence of active dinitrogen fixation in surface waters of the eastern tropical South Pacific during El Niño and la Niña events and evaluation of its potential nutrient controls
作者: Dekaezemacker J ; , Bonnet S ; , Grosso O ; , Moutin T ; , Bressac M ; , Capone D ; G
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2013
卷: 27, 期: 3 起始页码: 768
结束页码: 779
语种: 英语
英文关键词: ETSP
; HNLC
; N2 fixation
; nutrient limitation
; oligotrophic
; oxygen minimum zones
Scopus关键词: ETSP
; HNLC
; N2 fixation
; Nutrient limitations
; oligotrophic
; Oxygen minimum zone
; Chlorophyll
; Ocean habitats
; Surface waters
; Tropics
; Nutrients
; air-sea interaction
; chlorophyll
; concentration (composition)
; dissolved organic matter
; El Nino
; gyre
; La Nina
; nitrogen fixation
; nutrient limitation
; oxygen minimum layer
; primary production
; surface water
; Pacific Ocean
; Pacific Ocean (Tropical)
英文摘要: Biological N2 fixation rates were quantified in the Eastern Tropical South Pacific (ETSP) during both El Niño (February 2010) and La Niña (March-April 2011) conditions, and from Low-Nutrient, Low-Chlorophyll (20°S) to High-Nutrient, Low-Chlorophyll (HNLC) (10°S) conditions. N2 fixation was detected at all stations with rates ranging from 0.01 to 0.88 nmol N L-1 d-1, with higher rates measured during El Niño conditions compared to La Niña. High N2 fixations rates were reported at northern stations (HNLC conditions) at the oxycline and in the oxygen minimum zone (OMZ), despite nitrate concentrations up to 30 μmol L-1, indicating that inputs of new N can occur in parallel with N loss processes in OMZs. Water-column integrated N2 fixation rates ranged from 4 to 53 μmol N m-2 d-1 at northern stations, and from 0 to 148 μmol m-2 d-1 at southern stations, which are of the same order of magnitude as N2 fixation rates measured in the oligotrophic ocean. N2 fixation rates responded significantly to Fe and organic carbon additions in the surface HNLC waters, and surprisingly by concomitant Fe and N additions in surface waters at the edge of the subtropical gyre. Recent studies have highlighted the predominance of heterotrophic diazotrophs in this area, and we hypothesize that N2 fixation could be directly limited by inorganic nutrient availability, or indirectly through the stimulation of primary production and the subsequent excretion of dissolved organic matter and/or the formation of micro-environments favorable for heterotrophic N2 fixation. Key Points High N2 fixation was measured in the OMZ and below the euphotic zoneHigh N2 fixation was measured in water masses with high nitrate concentrationsFe, DOC, and DIN additions through (in)direct mechanism stimulated N2 fixation ©2013. 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/77593
Appears in Collections: 气候变化事实与影响
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作者单位: Aix Marseille Université CNRS/INSU, IRD, Mediterranean Institute of Oceanography, Marseille, France; Max Planck Institute for Marine Microbiology, DE-28195 Bremen, Germany; ACRI-ST, Sophia-Antipolis, France; CNRS-INSU, Université Pierre et Marie Curie-Paris 6, Observatoire Océanologique, Villefranche-sur-Mer, France; Department of Marine and Environmental Biology, University of Southern California, Los Angeles, CA, United States
Recommended Citation:
Dekaezemacker J,, Bonnet S,, Grosso O,et al. Evidence of active dinitrogen fixation in surface waters of the eastern tropical South Pacific during El Niño and la Niña events and evaluation of its potential nutrient controls[J]. Global Biogeochemical Cycles,2013-01-01,27(3)