Celtic Sea

Suspended particulate material aggregates; Chlorophyll pigment concentrations in water bodies; Zooplankton growth rates; Suspended particulate material setting velocity parameters; Primary production in the water column; Salinity of the water column; Temperature of the water column; Bacterial production in the water column; Zooplankton taxonomy-related abundance per unit volume of the water column; Phytoplankton growth; Concentration of suspended particulate material in the water column; Suspended particulate material grain size parameters; Zooplankton egg hatch proportion; Phytoplankton taxonomic abundance in water bodies; Nitrogen concentrations in sediment; Phytoplankton taxonomic biomass in water bodies; Carbon concentrations in sediment; Zooplankton feeding

Fluorometers; nutrient analysers; plankton recorders; plankton nets; CTD undulators; CTD; shipboard incubators

The project was an investigation of the role of picoplankton in pelagic productivity of a shelf sea. In 1979, the first descriptions appeared in the literature of a class of very small phytoplankton (less than 1.0 micron in diameter). Most of these phytoplankton were marine cyanobacteria, but there were also a number of eukaryotic algae which were also extremely small. The study involved measuring primary productivity of 3 size classes of phytoplankton, less than 1 micron, 1-5 microns, and greater then 5 microns in diameter. The smallest size fraction was found to account for about 25 per cent of the annual productivity and the other 2 size fractions were both just less than 40 per cent. A number of physiological measurements were done to determine the relationship between photosynthetic rate and irradiance. Samples of zooplankton were taken to determine how much of the secondary production was supported by the different size fractions of phytoplankton.

Plymouth Marine Laboratory
Prospect Place The Hoe
Plymouth
England
PL1 3DH
United Kingdom