MEPS 160:57-62 (1997)  -  doi:10.3354/meps160057

Three species of vertically migrating copepods (Pleuromamma pisekii, P. gracilis and P. abdominalis) were collected at dawn and at dusk from the upper 200 m in the North Atlantic (36.5°N, 19.2°W) between 11 and 18 July 1996. For all 3 species, the nitrogen content of individuals caught at dawn was significantly greater than for individuals caught at dusk. Theoretical considerations suggest that this dawn-dusk difference in nitrogen content represents material that is exported from the surface each day (the so called active N-flux). The rate of this active N-flux was 0.46 µg N ind.^-1 d^-1 for P. pisekii, 0.34 µg N ind.^-1 d^-1 for P. gracilis and 5.17 µg N ind.^-1 d^-1 for P. abdominalis.

Zooplankton · Diel vertical migration · Nitrogen · Vertical export · Biogeochemical impact · N-flux · Atlantic · PRIME