picoplanktonn.

1978 J. McN. Sieburth et al. in Limnol. & Oceanogr. 23 1261/1 The size fractions occupied by the bacterioplankton (0.2–2.0 μm) and virioplankton (0.02–0.2 μm) have been termed picoplankton and femtoplankton. The basis for this is the fortunate naming of the two larger size fractions in the nanoplankton and microplankton... This is all the more applicable if the plankton organisms are regarded on the basis of volume (three-dimensional) rather than length (one-dimensional) and are assumed to have a cubic shape and a density of 1 g.cm⁻³.

1983 Sci. Amer. June 62/2 The intent was to trap picoplankton: organisms whose wet weight is on the order of a picogram, or 10⁻¹² gram.

1998 Conservation Biol. 12 1227/1 Seasonal changes in nutrient inputs..tend to shift phytoplankton populations from a late fall–winter picoplankton population to a spring–summer diatom-dominated community.

1982 Marine Biol. 67 68/1 Our previous assumption..that a 3 μm filter effectively separated phytoplankton and bacteria was evidently due to our failure to detect the picoplanktonic algal forms.

1999 Limnol. & Oceanogr. 44 259/2 The fate of picoplanktonic microorganisms in marine food webs has been linked..to the grazing activities of small protists.