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| Titel |
A dynamic climate and ecosystem state during the Paleocene-Eocene Thermal Maximum: inferences from dinoflagellate cyst assemblages on the New Jersey Shelf |
| VerfasserIn |
A. Sluijs, H. Brinkhuis |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 6, no. 8 ; Nr. 6, no. 8 (2009-08-25), S.1755-1781 |
| Datensatznummer |
250003960
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| Publikation (Nr.) |
 copernicus.org/bg-6-1755-2009.pdf |
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| Zusammenfassung |
| Late Paleocene and Early Eocene climates and ecosystems underwent
significant change during several transient global warming phases,
associated with rapidly increasing atmospheric carbon concentrations, of
which the Paleocene-Eocene Thermal Maximum (PETM; ~55.5 Ma) is best
studied. While biotic response to the PETM as a whole (~170 kyrs) has
been relatively well documented, variations during the PETM have been neglected.
Here we present organic dinoflagellate cyst (dinocyst) distribution patterns
across two stratigraphically expanded PETM sections from the New Jersey
Shelf, Bass River and Wilson Lake. Many previously studied sites show a
uniform abundance of the thermophilic and presumably heterotrophic taxon
Apectodinium that spans the entire carbon isotope excursion (CIE) of the PETM. In
contrast, the New Jersey sections show large variations in abundances of
many taxa during the PETM, including the new species Florentinia reichartii that we formally
propose. We infer paleoecological preferences of taxa that show temporal
abundance peaks, both qualitative and absolute quantitative, from empirical
as well as statistical information, i.e., principle (PCA) and canonical
correspondence analyses (CCA). In the CCAs, we combine the dinocyst data
with previously published environmental proxy data from these locations,
such as TEX86 paleothermometry, magnetic susceptibility and sedimentary
size fraction. The combined information supports previous inferences that
sea level rose during the PETM, but also indicates a (regional) increase in
fresh-water runoff that started ~10 kyr after the onset of the CIE,
and perhaps precession-paced cycles in sea surface productivity. The highly
variable dinocyst assemblages of the PETM contrast with rather stable Upper
Paleocene assemblages, which suggests that carbon input caused a dynamic
climate state, at least regionally. |
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