@article{fdi:010083813,
  title = {{P}elagic {N}-2 fixation dominated by sediment diazotrophic communities in a shallow temperate estuary},
  author = {{H}allstrom, {S}. and {B}enavides, {M}ar and {S}alamon, {E}. {R}. and {E}vans, {C}. {W}. and {P}otts, {L}. {J}. and {G}ranger, {J}. and {T}obias, {C}. {R}. and {M}oisander, {P}. {H}. and {R}iemann, {L}.},
  editor = {},
  language = {{ENG}},
  abstract = {{E}stuaries receive substantial anthropogenic nitrogen loading and are mainly considered net nitrogen sinks. {W}hile several studies have identified diverse diazotrophic communities in estuarine sediments, the role of pelagic diazotrophs in these systems is not well understood. {W}e investigated the links between diazotrophic community composition, nitrogenase (nif{H}) gene expression, {N}-2 fixation, and environmental conditions in {N}arragansett {B}ay ({USA}). {P}elagic {N}-2 fixation rates ranged between 0.02 and 9.41 nmol {N} {L}-1 d(-1) and correlated significantly with fluctuations in diazotroph community composition. {T}hese fluctuations were also correlated with temperature, salinity, and mean sea level. {T}he dominant sequences in our pelagic samples were related to sequences previously detected in the bay's sediments and were dominated by nif{H} gene {C}lusters {I} and {III}. {W}e interpret this as a coupling between sediment and pelagic diazotroph communities and speculate that resuspension plays an important role for pelagic {N}-2 fixation in shallow estuarine environments such as {N}arragansett {B}ay. {F}or instance, the finding of active sulfate reducers in the oxygenated water illustrates that the sediment-pelagic coupling can impact nutrient cycling in shallow environments. {T}he pelagic {N}-2 fixation measured during our study period showed only a minor contribution (< 1%) to the total estimated nitrogen load to {N}arragansett {B}ay. {H}owever, with intensifying nitrogen management in estuaries, the need to constrain the rates of pelagic {N}-2 fixation in these systems will be essential for estimating nitrogen fluxes within the bay and to the adjacent coastal ecosystems.},
  keywords = {{ETATS} {UNIS} ; {NARRAGANSETT} {BAIE} ; {ZONE} {TEMPEREE}},
  booktitle = {},
  journal = {{L}imnology and {O}ceanography},
  volume = {67},
  numero = {2},
  pages = {364--378},
  ISSN = {0024-3590},
  year = {2022},
  DOI = {10.1002/lno.11997},
  URL = {https://www.documentation.ird.fr/hor/fdi:010083813},
}