FN Archimer Export Format
PT J
TI Major factors controlling Holocene delta C-13(org) changes in a seasonal sea-ice environment, Adelie Land, East Antarctica
BT 
AF CROSTA, X
   CRESPIN, J
   BILLY, I
   THER, O
AS 1:1;2:1;3:1;4:1;
FF 1:;2:;3:;4:;
C1 Dept Geol & Oceanog, UMR CNRS EPOC 5805, F-33405 Talence, France.
C2 CNRS, FRANCE
IF 3.373
TC 19
UR https://archimer.ifremer.fr/doc/00230/34080/32534.pdf
LA English
DT Article
CR MD 130 / CADO
BO Marion Dufresne
AB In an effort to investigate the controlling factors behind Holocene delta C-13(org) changes in East Antarctica we report high-resolution down-core records of bulk organic matter carbon isotopic ratios (delta C-13(org)), diatom census counts, total organic carbon, and biogenic silica content taken from one core recovered in the Adelie Trough. A good correspondence between the delta C-13(org) record and records of small/large and pennate/centric ratios in many of the core segments indicates that diatom species composition affected Holocene delta C-13(org) variations, possibly via diatom shape and size effects. Variations in the surface water CO2 concentration and in the isotopic composition of the source during the Holocene cannot be ruled out although they cannot explain rapid and large-amplitude delta C-13(org) changes. Within the limit of our investigation, our results argue against active carbon acquisition through a carbon concentration mechanism as evidenced in low-latitude upwelling systems. The bulk organic matter thus represents a mixing of diatom taxa having different fractionation affinity to aqueous CO2. Our results confirm previous evidence which demonstrates that delta C-13(org) down-core records should be used with great caution to reconstruct past CO2 content in surface waters.
PY 2005
PD DEC
SO Global Biogeochemical Cycles
SN 0886-6236
PU Amer Geophysical Union
VL 19
IS 4/GB4029
UT 000234506200004
BP 1
EP 9
DI 10.1029/2004GB002426
ID 34080
ER

EF