APPENDIX A 



CARBON FIXATION (C ^4) AND PHYTOPLANKTON DATA 

 FROM H UGH M. SMITH CRUISE 46 



By 



Mikihiko Oguri 

 Junior Botanist , 

 University of Hawaii- 

 Primary productivity measurements were made during the cruise using the radiocarbon tra- 

 cer technique as modified by Doty and Oguri (1958) from that first describ^ad by Steemann Nielsen 

 (1952). This technique consists of introducing a known quantity of radiocarbon to a sample of water 

 containing the natural phytoplankton population. Following a period of incubation at a uniform light 

 intensity, the water is filtered off leaving the phytoplankton on the filter. These filters are stored 

 in a dessicator for later determination of the amount of radiocarbon biologically fixed. From this 

 the total carbon uptake may be calculated. 



Pigment concentrations were determined by the method described by Richards and Thompson 

 (1952). Phytoplankton from a measured volume of sea water was collected on a Millipore filter. 

 These filters were stored in a darkened, refrigerated dessicator. Upon return to the laboratory the 

 pigments were extracted with 90-percent acetone and the extinctions of the extract for the wave 

 lengths of peak absorbance for the pigments were spectrophotometrically determined. Conversion 

 of the extinction values obtained to units of pigment was accomiplished by use of the formulae listed 

 by Richards and Thompson (1952). 



LITERATURE CITED 



DOTY, MAXWELLS, and M. OGURI 



1958. Selected features of the isotopic carbon primary productivity technique. Rapports et 

 Proces-Verbaux des reunions, Conseil Permanent International pour I'Exploration de laMer 

 144: 47-55. 



RICHARDS, FRANCIS A. and T. G. THOMPSON 



1952. The estimation and characterization of plankton populations by pigment analyses. II. A 

 spectrophotometric method for the estimation of plankton pigments. Journal of Marine Re- 

 search 11(2): 156-172. 



The tabulated data on carbon fixation and photosynthetic pigments are arranged in the chrono- 

 logical order of sampling. Unless otherwise specified, the samples were from the surface. Where 

 the position of sampling is not specified, it is understood to be the same as that of the preceding 

 sample . 



The word "Carboy" appearing in the "Station" column of the table as a source of samples refer s 

 to three occasions during the cruise when a 5-gallon container was filled with surface water, from 

 which samples were subsequently drawn at intervals to study the diurnal periodicity of production. 

 The carboys were in each case filled at the position specified immediately before their first mention, 

 and the subsamples were drawn from them and processed when regular surface samples were taken. 



1/ Work done under contract at-(04-3)-15 with the U. S. Atonnic Energy Commission. 



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