@article{fdi:010064078,
  title = {{A} coupled stable isotope-size spectrum approach to understanding pelagic food-web dynamics : a case study from the southwest sub-tropical {P}acific},
  author = {{H}unt, {B}. {P}. {V}. and {A}llain, {V}. and {M}enk{\`e}s, {C}hristophe and {L}orrain, {A}nne and {G}raham, {B}. and {R}odier, {M}artine and {P}agano, {M}arc and {C}arlotti, {F}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}his study investigated the food web structure of the oligotrophic picophytoplankton-dominated pelagic ecosystem in the vicinity of {N}ew {C}aledonia, within the {A}rchipelagic {D}eep {B}asin ({ARCH}) province of the southwest sub-tropical {P}acific. {N}itrogen stable isotope (delta {N}-15) data were collected for mesozooplankton (0.2-2 mm), macrozooplankton (2-20 mm), micronelcton (20-200 mm) and nekton ( >200 mm) during 2002-2004 and 2011. {U}sing a coupled delta {N}-15 size-spectrum approach, we estimated (1) organism trophic level ({TL}); (2) food chain length ({FCL}); (3) predator prey mass ratio ({PPMR}); and (4) transfer efficiency ({TE}). {T}he role of phytoplankton size structure in determining these parameters was investigated. {A}pplying atrophic enrichment factor ({TEF}) of 3.4, maximum {TL} was calculated at similar to 5. {T}he number of {TL}s spanned by each length class was 1.97 for mesozooplankton, 2.07 for macrozooplankton, 2.75 for micronekton, and 2.21 for nekton. {E}stimated {PPMR} was 10,099:1 for mesozooplankton, 3683:1 for macrozooplankton/micronekton, and 2.44 x 10(5):1 for nekton, corresponding to {TE}s of 6.3%, 8.5% and 2.4%, respectively. {PPMR} and {TE} were strongly influenced by the {TEF} used, and {TEF} 3.4 likely over and underestimated {PPMR} and {TE}, respectively, for mesozooplankton and macrozooplankton/micronekton. {C}omparatively low {PPMR} for mesozooplankton and macrozooplankton/micronekton indicated longer food chains and higher connectivity within these groups than for the nekton. {C}onversely, the high {PPMR} yet high trophic niche width for the nekton indicated that they prey primarily on macrozooplankton/micronekton, with a relatively high degree of dietary specialisation. {O}ur results are discussed in the context of other marine food webs. {T}he {ARCH} food chain was found to be 1-1.5 trophic levels longer than the eutrophic micro-/nanophytoplankton-dominated {C}alifornian upwelling system, providing empirical support for the role of phytoplankton size in determining {FCL} {G}roup specific {PPMR} estimates demonstrated that it is changes in trophic pathways across the mesozooplankton/macrozooplankton/ micronekton groups that are primarily responsible for higher {FCL} under oligotrophic conditions. {F}inally, we discuss consistently low delta {N}-15 values to the east of {N}ew {C}aledonia, and implications for the contribution of diazotroph nitrogen to the pelagic food web in this region.},
  keywords = {{F}ood webs ; {S}outh {P}acific ; {S}table isotopes ; {Z}ooplankton ; {M}icronekton ; {N}ekton ; {F}ood chain length ; {D}iazotroph ; {PACIFIQUE} {SUD}},
  booktitle = {{I}mpacts of climate on marine top predators},
  journal = {{D}eep-{S}ea {R}esearch {P}art {II} : {T}opical {S}tudies in {O}ceanography},
  volume = {113},
  numero = {{N}o sp{\'e}cial},
  pages = {208--224},
  ISSN = {0967-0645},
  year = {2015},
  DOI = {10.1016/j.dsr2.2014.10.023},
  URL = {https://www.documentation.ird.fr/hor/fdi:010064078},
}