North and north west Atlantic coasts of Spain

Zooplankton and zoobenthos morphological parameters; Electrical conductivity of the water column; Chlorophyll pigment concentrations in water bodies; Zooplankton growth rates; Suspended particulate material setting velocity parameters; Zooplankton reproduction rate parameters; Salinity of the water column; Plankton abundance per unit volume of the water column; Temperature of the water column; Zooplankton taxonomy-related abundance per unit volume of the water column; Zooplankton taxonomy-related biomass expressed as carbon per unit volume of the water column; Concentration of suspended particulate material in the water column; Suspended particulate material grain size parameters; Plankton biomass expressed as carbon per unit volume of the water column; Zooplankton and zoobenthos development stage parameters; Zooplankton egg hatch proportion; Phytoplankton taxonomic abundance in water bodies; Nitrogen concentrations in sediment

Fluorometers; nutrient analysers; plankton recorders; plankton nets; CTD undulators; CTD; plankton categorisers and counters

This work is part of a European Community funded project to examine reasons for recruitment variability in clupeids. The basis of the approach is to derive an annual larval production curve and then later in the year to derive from which time during the spawning season the surviving juveniles have originated. The nutritional condition of larvae preserved during the cruises to determine the larval production is examined in conjunction with hydrographic and biological measurements to relate the relatively good and poor periods of survival to environmental factors. A preliminary cruise was carried out in April/May 1991 to establish an efficient sampling protocol for the main series of five by three week cruises between April and July 1992. The sampling grid on all the cruises was based on a series of 20 transects at approximately right angles to the coast each with 4 stations spaced at 10 mile intervals, CTD and plankton sampling being carried out at each station.

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