The Relation Between New Production, as Estimated by Exported Nitrogen and total Primary Production
Under steady-state conditions, the f-ratio (new:total primary production), should be equivalent whether calculated with new production measured from allochthonous nitrogen uptake, or from particulate nitrogen export from the euphotic zone. In comparing several marine sites; Monterey Bay, the eastern equatorial Pacific, and the central north Pacific gyre, the f-ratios based on PON fluxes and Redfield ratio-converted 14C-uptake primary production exhibit a direct relation to primary production; in general, higher f-ratios are found with the higher primary production and vice versa. However, some data sets show significant variation. At times, (early upwelling in Monterey Bay, likely a non steady-state) this relation does not hold, and over much of the year, primary production and the f-ratio are inversely related.