F-ratio (oceanography)

For other uses, see F-ratio.
Empirically derived effect of temperature and Net Primary Productivity on the f-ratio, and approximate values for some large ocean regions.[citation needed]
Part of a series on
Plankton
Phytoplankton
Trophic mode
By size
By taxonomy
By habitat
Other types
Blooms
Related topics

In oceanic biogeochemistry, the f-ratio is the fraction of total primary production fuelled by nitrate (as opposed to that fuelled by other nitrogen compounds such as ammonium). The ratio was originally defined by Richard Eppley and Bruce Peterson in one of the first papers estimating global oceanic production.[1] This fraction was originally believed significant because it appeared to directly relate to the sinking (export) flux of organic marine snow from the surface ocean by the biological pump. However, this interpretation relied on the assumption of a strong depth-partitioning of a parallel process, nitrification, that more recent measurements has questioned.[2]

  1. ^ Eppley, R.W.; Peterson, B.J. (1979). "Particulate organic matter flux and planktonic new production in the deep ocean". Nature. 282 (5740): 677–680. Bibcode:1979Natur.282..677E. doi:10.1038/282677a0. S2CID 42385900.
  2. ^ Yool, A.; Martin, A.P.; Fernández, C.; Clark, D.R. (2007). "The significance of nitrification for oceanic new production". Nature. 447 (7147): 999–1002. Bibcode:2007Natur.447..999Y. doi:10.1038/nature05885. PMID 17581584. S2CID 4416535.