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Meckler, A. Nele; Ren, Haojia; Sigman, Daniel M.; Gruber, Nicolas; Plessen, Birgit; Schubert, Carsten J.; Haug, Gerald H.. |
Constraining variations in marine N(2)-fixation over glacial-interglacial timescales is crucial for determining the role of the marine nitrogen cycle in modifying ocean productivity and climate, yet paleo-records from N2-fixation regions are sparse. Here we present new nitrogen isotope (delta(15)N) records of bulk sediment and foraminifera test-bound (FB) nitrogen extending back to the last ice age from the oligotrophic Gulf of Mexico (GOM). Previous studies indicate a substantial terrestrial input during the last ice age and early deglacial, for which we attempt to correct the bulk sediment delta(15)N using its observed relationship with the C/N ratio. Both corrected bulk and FB-delta(15)N reveal a substantial glacial-to-Holocene decrease of delta(15)N... |
Tipo: Text |
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Ano: 2011 |
URL: https://archimer.ifremer.fr/doc/00227/33786/32567.pdf |
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