Seawater was collected using 10-L teflon-lined Go-flo bottles mounted on the Neil Brown CTD rosette. Water was drained into opaque brown 1-L bottles immediately after collection and refrigerated until processed. Samples were collected onto filters within one hour of water collection. In areas where the water column was well mixed, water was collected from the top, middle and bottom of the water column. When the water column was stratified, water was collected from the top, middles and bottom of the water column as well as around the hydrographic features of interest.
DMO note: The data reported consists of three replicates per each depth horizon sampled.
\nPI Responsible: Dian J. Gifford
\nSamples for water column chlorophyll and phaeopigment were collected and analyzed during the following Vital rates 1995 U.S. GLOBEC Georges Bank process cruises:
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\nWater Collection: Seawater was collected using 10-L teflon-lined Go-flo bottles mounted on the Neil Brown CTD rosette. Water was drained into opaque brown 1-L bottles immediately after collection and refrigerated until processed. Samples were collected onto filters within one hour of water collection. In areas where the water column was well mixed, water was collected from the top, middle and bottom of the water column. When the water column was stratified, water was collected from the top, middles and bottom of the water column as well as around the hydrographic features of interest.
\nSample Processing: Samples were prepared for total, <20 \u00b5m, and <5 \u00b5m chlorophyll and phaeopigment. Samples for total pigments consisted of bulk seawater. Samples for < 20 \u00b5m and < 5 \u00b5m pigments were passed gently through clean Nitex meshes of appropriate porosity and the filtrate retained for analysis. Three replicate 50-ml samples of each size fraction were collected onto 25 mm GF/F filters, placed into 5 ml of 90% acetone in a capped test tube, and extracted in the freezer for 24 hours prior to analysis.
\nSample Analysis: The filters were removed from defrosted test tubes with a clean stainless steel spatula, the tube wiped clean with a Kimwipe, and samples read on a Turner Designs Model 10 fluorometer before and after acidification with 10% HCl (Parsons et al., 1984).
\nCaveat: In general, pigment concentrations in the <5 \u00b5m samples were approximately equal to the <20 \u00b5m samples (i.e., there was very little chlorophyll in the 5-20 \u00b5m size range: most chlorophyll < 20 \u00b5m was also < 5 \u00b5m). Because of the difficulty of passing seawater quantitatively through the 5 \u00b5m mesh, the <5 \u00b5m data are more variable than the Total and < 20 \u00b5m data. To avoid confusion, the < 5 \u00b5m data are not included in the data files. The data are available, and scientific investigators who need it should contact the PI directly.
\nData Use: The data are available for use by any scientific investigator who wishes to use them. The PI must be consulted prior to publication.
\n\n\nData Submitted by: \n\nDian J. Gifford\nGraduate School of Oceanography\nUniversity of Rhode Island\nNarragansett, RI 02882-1197\n\nvoice: 401-874-6690\nfax: 401-874-6240\ne-mail: gifford@gsosun1.gso.uri.edu\n\nupdated: Aug 05. 2005, gfh\n
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Sample Processing: Samples were prepared for total, <20 \u00ef\u00bf\u00bdm, and <5 \u00ef\u00bf\u00bdm chlorophyll and phaeopigment. Samples for total pigments consisted of bulk seawater. Samples for < 20 \u00ef\u00bf\u00bdm and < 5 \u00ef\u00bf\u00bdm pigments were passed gently through clean Nitex meshes of appropriate porosity and the filtrate retained for analysis. Three replicate 50-ml samples of each size fraction were collected onto 25 mm GF/F filters, placed into 5 ml of 90% acetone in a capped test tube, and extracted in the freezer for 24 hours prior to analysis.
\nSample Analysis: The filters were removed from defrosted test tubes with a clean stainless steel spatula, the tube wiped clean with a Kimwipe, and samples read on a Turner Designs Model 10 fluorometer before and after acidification with 10% HCl (Parsons et al., 1984).
\nCaveat: In general, pigment concentrations in the <5 \u00ef\u00bf\u00bdm samples were approximately equal to the <20 \u00ef\u00bf\u00bdm samples (i.e., there was very little chlorophyll in the 5-20 \u00ef\u00bf\u00bdm size range: most chlorophyll < 20 \u00ef\u00bf\u00bdm was also < 5 \u00ef\u00bf\u00bdm). Because of the difficulty of passing seawater quantitatively through the 5 \u00ef\u00bf\u00bdm mesh, the <5 \u00ef\u00bf\u00bdm data are more variable than the Total and < 20 \u00ef\u00bf\u00bdm data. To avoid confusion, the < 5 \u00ef\u00bf\u00bdm data are not included in the data files. The data are available, and scientific investigators who need it should contact the PI directly.