@article{fdi:010073657,
  title = {{M}odelling {N}-2 fixation related to {T}richodesmium sp. : driving processes and impacts on primary production in the tropical {P}acific {O}cean},
  author = {{D}utheil, {C}. and {A}umont, {O}livier and {G}orgues, {T}homas and {L}orrain, {A}nne and {B}onnet, {S}ophie and {R}odier, {M}artine and {D}upouy, {C}{\'e}cile and {S}hiozaki, {T}. and {M}enk{\`e}s, {C}hristophe},
  editor = {},
  language = {{ENG}},
  abstract = {{D}initrogen fixation is now recognized as one of the major sources of bio-available nitrogen in the ocean. {T}hus, {N}-2 fixation sustains a significant part of the global primary production by supplying the most common limiting nutrient for phytoplankton growth. {T}he "{O}ligotrophy to {U}l{T}ra-oligotrophy {PAC}ific {E}xperiment"({OUTPACE}) improved the data coverage of the western tropical {S}outh {P}acific, an area recently recognized as a hotspot of {N}-2 fixation. {T}his new development leads us to develop and test an explicit {N}-2 fixation formulation based on the {T}richodesmium physiology (the most studied nitrogen fixer) within a 3-{D} coupled dynamical-biogeochemical model ({ROMS}-{PISCES}). {W}e performed a climatological numerical simulation that is able to reproduce the main physical (e.g. sea surface temperature) and biogeochemical patterns (nutrient and chlorophyll concentrations, as well as {N}-2 fixation) in the tropical {P}acific. {T}his simulation displayed a {T}richodesmium regional distribution that extends from 150 degrees {E} to 120 degrees {W} in the south tropical {P}acific, and from 120 degrees {E} to 140 degrees {W} in the north tropical {P}acific. {T}he local simulated maximuma were found around islands ({H}awaii, {F}iji, {S}amoa, {N}ew {C}aledonia, {V}anuatu). {W}e assessed that 15% of the total primary produc-tion may be due to {T}richodesmium in the low-nutrient lowchlorophyll regions ({LNLC}) of the tropical {P}acific. {C}omparison between our explicit and the often used (in biogeochemical models) implicit parameterization of {N}-2 fixation showed that the latter leads to an underestimation of {N}-2 fixation rates by about 25% in {LNLC} regions. {F}inally, we established that iron fluxes from island sediments control the spatial distribution of {T}richodesmium biomasses in the western tropical {S}outh {P}acific. {N}ote, this last result does not take into account the iron supply from rivers and hydrothermal sources, which may well be of importance in a region known for its strong precipitation rates and volcanic activity.},
  keywords = {{PACIFIQUE}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {15},
  numero = {14},
  pages = {4333--4352},
  ISSN = {1726-4170},
  year = {2018},
  DOI = {10.5194/bg-15-4333-2018},
  URL = {https://www.documentation.ird.fr/hor/fdi:010073657},
}