Primary production, biomass, size structure and nitrogen nutrition of phytoplankton in the Coral Sea (RV Franklin Cruise 05/85)

Subsamples of water for chlorophyll analyses were taken from water samples collected in the upper 150 meters at most first leg stations. In addition to unfractionated subsamples (total population), portions of the subsamples were size-fractionated through 10 and 22μm screens to estimate the contributions of net- (>10μm), nano- (10-2μm) and pico-phytop1ankton 2 and 0.5% surface irradiance) depths generally exceed 120 m. On one occasion, a secchi disk depth of 47 meters was recorded. Under normal good viewing conditions, secchi depths were generally between 35 and 40 m.Duplicate vertical zooplankton tows (60μm mesh) were made daily at each productivity station to obtain an estimate of zooplankton biomass and community structure in the euphotic zone. A limited number of tows were made at night to give comparative day/night changes.This research was undertaken during legs 1 and 2 of the RV Franklin Cruise 5/85.Leg 1 - 1/10/85 to 21/10/85Leg 2 - 23/10/85 to 5/11/85