some aspects of the biochemical and mineral composition of marine plankton

A natural population of phytoplankton and two species of zooplankton, Calanus finmarchicus (Gunnerus) (stage V) and Sagitta elegans (Verrill) (mature), were analysed for their biochemical and mineral composition. Comparison with published data for the same categories of plankton shows that the distribution of both organic and mineral fractions is highly variable, the causes of which are not equally understood. The composition of the organic fraction is affected by the duality of function of the biochemical constituents and by the large number of ecological factors which influence their concentration. Whether this applies to the mineral fraction remains uncertain; nevertheless it appears that plankton concentrate trace metals, that phytoplankton has a greater ability to concentrate them than zooplankton, and that the ability of zooplankton to concentrate various metals varies with the species.