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| Crosta, X; Crespin, J; Billy, I; Ther, O. |
| 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... |
| Tipo: Text |
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| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00230/34080/32534.pdf |
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| Crosta, X; Shemesh, A; Etourneau, J; Yam, R; Billy, I; Pichon, Jj. |
| Most high-southern latitude records of carbon and nitrogen isotopic ratios and elemental ratios are from the Antarctic and Polar Front zones, thus hindering a comprehensive view of nutrient cycling in the Southern Ocean. We present, for the first time, two records from the Subantarctic Zone and the southern Subtropical Zone of the Indian Ocean. These records provide a latitudinal transect covering the main oceanographic systems of the Southern Ocean. Carbon and nitrogen content of the diatom-bound organic matter increases during the last glacial in the Antarctic and Subantarctic zones but does not show a clear climate-related signal in the Subtropical Zone. Comparison of these records with sea-surface temperatures reconstructed at the core locations and... |
| Tipo: Text |
Palavras-chave: Diatoms; Nutrient cycling; Southern Ocean. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00230/34075/32543.pdf |
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