IN his recent discussion of the fertility of ocean waters, Harvey1 mentions that "A phenomenon which seems to lack explanation is the time at which phytolankton start to increase rapidly at the beginning of the year", for by mid-winter all the known nutrient salts have been regenerated and, in spite of the bright light of spring, the steep increase in the phytoplankton, as shown by the decrease in phosphate, becomes apparent in the English Channel normally only between March and April, and even much later elsewhere. He mentions the well-known effect of turbulence in carrying the cells down into regions of low illumination, and suggests that there are unrecognized factors controlling the inception of growth in some areas. Sverdrup2 also states: "This conditioning of the water may well be a factor in the initial outburst of phytoplankton growth when other conditions are optimum"; thus he also alludes to an unknown factor.
Harvey, H. W., Recent Advances in the Chemistry and Biology of Sea Water' (Cambridge, 1945).
Sverdrup, H. U., Johnson, M. W., and Fleming, R. H., The Oceans (New York, 1942).
Atkins, W. R. G., J. Mar. Biol. Assoc., 13, 119 (1923).
Poole, H. H., and Atkins, W. R. G., J. Mar. Biol. Assoc., 16, 297 (1929).
Atkins, W. R. G., J. Mar. Biol. Assoc., 13, 693 (1925); and J. Conseil Internat. Expl. de la Mer, 1, 99 (1926).
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ATKINS, W. Conditions for the Vernal Increase in the Phytoplankton and a Supposed Lag in the Process. Nature 156, 599 (1945). https://doi.org/10.1038/156599a0
Biographical Memoirs of Fellows of the Royal Society (1960)