@article{fdi:010061267,
  title = {{E}vidence of active dinitrogen fixation in surface waters of the eastern tropical {S}outh {P}acific during {E}l {N}iño and {L}a {N}iña events and evaluation of its potential nutrient controls},
  author = {{D}ekaezemacker, {J}. and {B}onnet, {S}ophie and {G}rosso, {O}. and {M}outin, {T}. and {B}ressac, {M}. and {C}apone, {D}.{G}.},
  editor = {},
  language = {{ENG}},
  abstract = {{B}iological {N}-2 fixation rates were quantified in the {E}astern {T}ropical {S}outh {P}acific ({ETSP}) during both {E}l {N}ino ({F}ebruary 2010) and {L}a {N}ina ({M}arch-{A}pril 2011) conditions, and from {L}ow-{N}utrient, {L}ow-{C}hlorophyll (20 degrees {S}) to {H}igh-{N}utrient, {L}ow-{C}hlorophyll ({HNLC}) (10 degrees {S}) conditions. {N}-2 fixation was detected at all stations with rates ranging from 0.01 to 0.88nmol{NL}(-1) d(-1), with higher rates measured during {E}l {N}ino conditions compared to {L}a {N}ina. {H}igh {N}-2 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 mu mol{L}(-1), indicating that inputs of new {N} can occur in parallel with {N} loss processes in {OMZ}s. {W}ater-column integrated {N}-2 fixation rates ranged from 4 to 53 mu mol{N}m(-2) d(-1) at northern stations, and from 0 to 148 mu molm(-2) d(-1) at southern stations, which are of the same order of magnitude as {N}-2 fixation rates measured in the oligotrophic ocean. {N}-2 fixation rates responded significantly to {F}e and organic carbon additions in the surface {HNLC} waters, and surprisingly by concomitant {F}e and {N} additions in surface waters at the edge of the subtropical gyre. {R}ecent studies have highlighted the predominance of heterotrophic diazotrophs in this area, and we hypothesize that {N}-2 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 {N}-2 fixation.},
  keywords = {{MILIEU} {MARIN} ; {EAU} {DE} {SURFACE} ; {EL} {NINO} ; {FIXATION} {BIOLOGIQUE} {DE} {L}'{AZOTE} ; {PRODUCTION} {PRIMAIRE} ; {FACTEUR} {LIMITANT} ; {CHLOROPHYLLE} ; {NUTRIMENT} ; {OXYGENE} ; {OLIGOTROPHIE} ; {LA} {NINA} ; {N}2 fixation ; {ETSP} ; oligotrophic ; {HNLC} ; oxygen minimum zones ; nutrient ; limitation ; {ZONE} {TROPICALE} ; {PACIFIQUE} {SUD}},
  booktitle = {},
  journal = {{G}lobal {B}iogeochemical {C}ycles},
  volume = {27},
  numero = {3},
  pages = {768--779},
  ISSN = {0886-6236},
  year = {2013},
  DOI = {10.1002/gbc.20063},
  URL = {https://www.documentation.ird.fr/hor/fdi:010061267},
}