@article{fdi:010090268,
  title = {{G}lobal oceanic diazotroph database version 2 and elevated estimate of global oceanic {N}-2 fixation},
  author = {{S}hao, {Z}. {B}. and {X}u, {Y}. {C}. and {W}ang, {H}. and {L}uo, {W}. {C}. and {W}ang, {L}. {C}. and {H}uang, {Y}. {H}. and {A}gawin, {N}. {S}. {R}. and {A}hmed, {A}. and {B}enavides, {M}ar and {B}iegala, {I}sabelle and {B}onnet, {S}ophie and {D}upouy, {C}{\'e}cile and {L}ory, {C}aroline and et al.},
  editor = {},
  language = {{ENG}},
  abstract = {{M}arine diazotrophs convert dinitrogen ({N}-2) gas into bioavailable nitrogen ({N}), supporting life in the global ocean. {I}n 2012, the first version of the global oceanic diazotroph database (version 1) was published. {H}ere, we present an updated version of the database (version 2), significantly increasing the number of in situ diazotrophic measurements from 13 565 to 55 286. {D}ata points for {N}-2 fixation rates, diazotrophic cell abundance, and nif{H} gene copy abundance have increased by 184 %, 86 %, and 809 %, respectively. {V}ersion 2 includes two new data sheets for the nif{H} gene copy abundance of non-cyanobacterial diazotrophs and cell-specific {N}2 fixation rates. {T}he measurements of {N}-2 fixation rates approximately follow a log-normal distribution in both version 1 and version 2. {H}owever, version 2 considerably extends both the left and right tails of the distribution. {C}onsequently, when estimating global oceanic {N}-2 fixation rates using the geometric means of different ocean basins, version 1 and version 2 yield similar rates (43-57 versus 45-63 {T}g{N}yr (-1); ranges based on one geometric standard error). {I}n contrast, when using arithmetic means, version 2 suggests a significantly higher rate of 223 +/- 30 {T}g{N}yr (-1) (mean +/- standard error; same hereafter) compared to version 1 (74 +/- 7 {T}g{N}yr (-1)). {S}pecifically, substantial rate increases are estimated for the {S}outh {P}acific {O}cean (88 +/- 23 versus 20 +/- 2 {T}g{N}yr 1), primarily driven by measurements in the southwestern subtropics, and for the {N}orth {A}tlantic {O}cean (40 +/- 9 versus 10 +/- 2 {T}g{N}yr (-1)). {M}oreover, version 2 estimates the {N}-2 fixation rate in the {I}ndian {O}cean to be 35 +/- 14 {T}g{N}yr (-1), which could not be estimated using version 1 due to limited data availability. {F}urthermore, a comparison of {N}-2 fixation rates obtained through different measurement methods at the same months, locations, and depths reveals that the conventional {N}-15(2) bubble method yields lower rates in 69% cases compared to the new {N}-15(2) dissolution method. {T}his updated version of the database can facilitate future studies in marine ecology and biogeochemistry. {T}he database is stored at the {F}igshare repository (https://doi.org/10.6084/m9.figshare.21677687; {S}hao et al., 2022).},
  keywords = {{MONDE}},
  booktitle = {},
  journal = {{E}arth {S}ystem {S}cience {D}ata},
  volume = {15},
  numero = {8},
  pages = {3673--3709},
  ISSN = {1866-3508},
  year = {2023},
  DOI = {10.5194/essd-15-3673-2023},
  URL = {https://www.documentation.ird.fr/hor/fdi:010090268},
}