| Summary: | Progress Code: completed Statement: This voyage is one of six which studied the abundance and distribution of both phytoplankton and Euphausia superba. They provided a good coverage of the area at varying season times and conditions. Data collection: Seven north-south transects were made between 58 degrees and 93 degrees east, with water samples collected at intervals of 5 degrees longitude. A General Oceanics rosette sampler equipped with twelve 5L Niskin botles was used for water collection in the top 200m of the water column. Standard depths for pigment analysis were used; 0, 10, 25, 35, 50, 75, 100, 200m. Temperature and salinity in the vertical profile were also measured, using a Neil Brown Mark 3 CTD. Ship-board processing: The water samples were analysed for oxygen, salinity, nutrients, and phytoplankton species. The remaining 2L to 4L of the water sample were filtered under a slight vacuum (approx. 0.5 atm.) using Whatman GF/F filters (0.7 micro-metre nominal pore size, 47mm diameter), and the filters were then immediately frozen in liquid nitrogen. Post-ship processing: The frozen filter was broken into 5mm diameter pieces, and sonicated in 4mL methanol using a Braun Labsonic 1510 sonicator equipped with a 4mm diameer needle probe (30 seconds at 50W). It was then filtered using a simple centrifugal system, described in Wright, S. and Shearer, J. (1984) Rapid extraction and high-performance liquid chromatography of chlorophylls and cartenoids from marine plankton. Journal of Chromatography 294:281-295. The filter debris was washed with 0.5mL methanol and recentrifuged. The combined extract was filtered through a Millex-HV filter unit (0.5 micro-metre pore size, Millipore Corp.). High performance liquid chromatography (HPLC) was used for pigment analysis. A 200 micro-litre sample of the extract was injected directly into a Waters Associates liquid chromatograph. Two RCM-100 radial compression modules were used in series. The pigments were eluted using a linear gradient from 90:10 acetonitrile:water to ...
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