Coupling of oceanic carbon and nitrogen facilitates spatially resolved quantitative reconstruction of nitrate inventories
Glock, N.; Erdem, Z.; Wallmann, K.; Somes, C.J.; Liebetrau, V.; Schönfeld, J.; Gorb, S.; Eisenhauer, A. (2018). Coupling of oceanic carbon and nitrogen facilitates spatially resolved quantitative reconstruction of nitrate inventories. Nature Comm. 9(1): 10 pp. https://doi.org/10.1038/s41467-018-03647-5
In: Nature Communications. Nature Publishing Group: London. ISSN 2041-1723; e-ISSN 2041-1723, more
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Authors | | Top |
- Glock, N.
- Erdem, Z., more
- Wallmann, K.
- Somes, C.J.
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- Liebetrau, V.
- Schönfeld, J.
- Gorb, S.
- Eisenhauer, A.
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Abstract |
Anthropogenic impacts are perturbing the global nitrogen cycle via warming effects and pollutant sources such as chemical fertilizers and burning of fossil fuels. Understanding controls on past nitrogen inventories might improve predictions for future global biogeochemical cycling. Here we show the quantitative reconstruction of deglacial bottom water nitrate concentrations from intermediate depths of the Peruvian upwelling region, using foraminiferal pore density. Deglacial nitrate concentrations correlate strongly with downcore δ1313>C, consistent with modern water column observations in the intermediate Pacific, facilitating the use of δ1313>C records as a paleo-nitrate-proxy at intermediate depths and suggesting that the carbon and nitrogen cycles were closely coupled throughout the last deglaciation in the Peruvian upwelling region. Combining the pore density and intermediate Pacific δ1313>C records shows an elevated nitrate inventory of >10% during the Last Glacial Maximum relative to the Holocene, consistent with a δ1313>C-based and δ15N-based 3D ocean biogeochemical model and previous box modeling studies. |
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