Nitrogen Fixation Within a Tropical Upwelling Ecosystem: Evidence for a Redfield Budget of Carbon/Nitrogen Cycling by the Total Phytoplankton Community

Authors

John J. Walsh, University of South FloridaFollow

Document Type

Article

Publication Date

9-15-1996

Digital Object Identifier (DOI)

https://doi.org/10.1029/96JC01877

Abstract

Recent measurements and paradigms suggest that (1) the uptake of dissolved carbon and nitrate by phytoplankton may be greater than the Redfield ratio of 6.6 and (2) the oceans may be loosing nitrogen from an imbalance in the global rates of nitrogen fixation and denitrification. An analysis of concurrent ΔDIC/ΔNO₃ depletion ratios within the Venezuelan and Peruvian upwelling ecosystems, indeed, suggests that values of 10.1–28.6 may pertain to these tropical eutrophic habitats. Nitrogen fixation may provide a Redfield balance in at least the former system, with 34–77% of the new production attributed to assimilation of N₂. Independent confirmation of such new production on the Venezuelan shelf is provided by the interannual increases of H₂S and DIC within the adjacent Cariaco Trench.

Rights Information

Terms of use for work posted in Scholar Commons.

Was this content written or created while at USF?

Yes

Citation / Publisher Attribution

Journal of Geophysical Research, v. 101, issue C9, p. 20607-20616

Scholar Commons Citation

Walsh, John J., "Nitrogen Fixation Within a Tropical Upwelling Ecosystem: Evidence for a Redfield Budget of Carbon/Nitrogen Cycling by the Total Phytoplankton Community" (1996). Marine Science Faculty Publications. 118.
https://digitalcommons.usf.edu/msc_facpub/118