PLANKTON ABUNDANCE IN THE NORTH ATLANTIC OCEAN (I). A ROTARY SYSTEM FOR CALIBRATING FLOW METERS (II).

• Main Authors: Be,Allan W. H., Forns,Joseph M., Harrison,Stanley
• Other Authors: LAMONT-DOHERTY GEOLOGICAL OBSERVATORY PALISADES N Y
• Format: Text
• Language: English
• Published: 1969
• Subjects: Biology; Biological Oceanography; Test Facilities; Equipment and Methods; *PLANKTON; *FLOWMETERS; ATLANTIC OCEAN; CALIBRATION; DISTRIBUTION; SAMPLING; COLLECTING METHODS; VOLUME; WEIGHT; OCEAN CURRENTS; DIURNAL VARIATIONS; ACCURACY; BIOMASS; NORTH ATLANTIC OCEAN; SEASONAL VARIATIONS; TAXONOMY; North Atlantic; Subarctic
• Online Access: http://www.dtic.mil/docs/citations/AD0690930; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0690930

Geographic variations in zooplankton biomass, expressed as displacement volume, wet weight, dry weight and ash weight, were determined from 246 plankton samples collected during 1958-1968 over wide regions of the North Atlantic. The study corroborates previous investigations that zooplankton abundancies are high in subarctic and cold-temperate waters, along oceanic margins, upwelling regions and active current systems -- where nutrient-rich mixed layers exist for varying durations of the year. The regional variations in zooplankton abundance are of sufficiently large magnitude that they mask variations due to diurnal vertical migration, local patchiness and non-synoptic sampling. However, seasonal variations in high latitudes are very large and they are likely to significantly alter our summer and fall estimates of biomass. The use of flow meters on plankton nets is standard procedure for quantitative sampling. A method for the periodic recalibration of both mechanical and electric flow meters is given. (Author)