Relationship between primary and export production in the boreal coastal zone of the North Atlantic

Abstract

Data from the literature on long‐term, simultaneous measurements of total primary production (PT) and sedimentation of particulate organic C (POC) close to the bottom of the photic zone, i.e. the export production (PE), are compared. Sufficient data are available only from the boreal coastal zone of the North Atlantic. A regression analysis revealed that PE is positively and nonlinearly related to PT and a power model (r2 = 0.94) was chosen. Comparison with published models predicting the vertical flux of POC from the upper water column (bottom of the photic zone or 50‐m depth) revealed that they do not adequately predict PE on the basis of PT in boreal coastal environments. It is suggested that PE in the boreal coastal zone should be calculated with the equation PE = 0.049 PT1.41. The 〈f〉 ratio, i.e. the ratio of PE : PT characterizing lengthy time intervals and the regenerated production (Pr) were calculated. Botht 〈f〉 and Pr are positively, nonlinearly correlated with PT, and the upper limit for 〈f〉 is about 0.5 in boreal coastal environments. Solar radiation at various latitudes influences the relationships among PE, Pr, 〈f〉, and PT.