FN Archimer Export Format
PT J
TI Export fluxes in a naturally iron-fertilized area of the Southern Ocean - Part 2: Importance of diatom resting spores and faecal pellets for export
BT 
AF REMBAUVILLE, M.
   BLAIN, S.
   ARMAND, L.
   QUEGUINER, B.
   SALTER, I.
AS 1:1,2;2:1,2;3:3;4:4,5;5:1,2,6;
FF 1:;2:;3:;4:;5:;
C1 Univ Paris 06, Univ Paris 04, Observ Oceanol, UMR7621,LOMIC, Banyuls Sur Mer, France.
   CNRS, LOMIC, Observ Oceanol, LOMIC, Banyuls Sur Mer, France.
   Macquarie Univ, Dept Biol Sci & Climate Futures, N Ryde, NSW 2109, Australia.
   Univ Toulon & Var, CNRS INSU, IRD,MOI,UM110, Marseille, France.
   Aix Marseille Univ, CNRS INSU, IRD,MOI,UM110, Marseille, France.
   Alfred Wegener Inst Polar & Marine Res, Bremerhaven, Germany.
C2 UNIV PARIS 06, FRANCE
   CNRS, FRANCE
   UNIV MACQUARIE, AUSTRALIA
   UNIV TOULON, FRANCE
   UNIV AIX MARSEILLE, FRANCE
   INST A WEGENER, GERMANY
IN DOAJ
IF 3.7
TC 49
UR https://archimer.ifremer.fr/doc/00295/40579/39498.pdf
   https://archimer.ifremer.fr/doc/00295/40579/39499.pdf
   https://archimer.ifremer.fr/doc/00295/40579/71317.pdf
LA English
DT Article
CR MD 145 / KEOPS
   MD 188 / KEOPS 2
BO Marion Dufresne
AB The biological composition of the material exported to a moored sediment trap located under the winter mixed layer of the naturally fertilized Kerguelen Plateau in the Southern Ocean was studied over an annual cycle. Despite iron availability in spring, the annual particulate organic carbon (POC) export (98.2 mmol m(-2)) at 289m was low, but annual biogenic silica export was significant (114 mmol m(-2)). This feature was related to the abundance of empty diatom cells and the ratio of full to empty cells exerted a first-order control in BSi : POC export stoichiometry of the biological pump. Chaetoceros Hyalochaete spp. and Thalassiosira antarctica resting spores were responsible for more than 60% of the annual POC flux that occurred during two very short export events of < 14 days in spring-summer. Relatively low diatom fluxes were observed over the remainder of the year. Faecal pellet contribution to annual carbon flux was lower (34 %) and reached its seasonal maximum in autumn and winter (> 80 %). The seasonal progression of faecal pellet types revealed a clear transition from small spherical shapes (small copepods) in spring, to larger cylindrical and ellipsoid shapes in summer (euphausiids and large copepods) and finally to large tabular shapes (salps) in autumn and winter. We propose in this high-biomass, low-export (HBLE) environment that small but highly silicified and fast-sinking resting spores are able to bypass the intense grazing pressure and efficient carbon transfer to higher trophic levels that are responsible for the low fluxes observed the during the remainder of the year. More generally our study also provides a statistical framework linking the ecological succession of diatom and zooplankton communities to the seasonality of carbon and silicon export within an iron-fertilized bloom region in the Southern Ocean.
PY 2015
PD JUL
SO Biogeosciences
SN 1726-4170
PU Copernicus Gesellschaft Mbh
VL 12
IS 11
UT 000356179800003
BP 3171
EP 3195
DI 10.5194/bg-12-3171-2015
ID 40579
ER

EF