Dataset: primary_prod
Deployment: AII-119-4

dataset:         Primary Production  (Carbon Assimilation)
project/cruise:  North Atlantic Bloom Experiment cruises

PI:              John Marra, C.A. Knudson, W.S. Chamberlin
of:              Lamont-Doherty Earth Observatory
dataset:         Primary Production  (Carbon Assimilation)
dates:           April 25, 1989 to May 08, 1989
location:        N: 47.0957  S: 46.3067  W: -20.2383  E: -19.0228
project/cruise:  North Atlantic Bloom Experiment/Atlantis II 119, leg 4
ship:            R/V  Atlantis II

Marra Primary Production Methodology

C. Knudson, W.S. Chamberlin, J. Marra
Lamont-Doherty Geological Observatory 

Methods reported below were extracted from:
Knudson, C., W.S. Chamberlin, J. Marra, 1989. Primary production and
irradiance data for U.S. JGOFS (leg 2) ATLANTIS II (Cruise 119-4).
Technical Report LDGO-89.4.  Lamont-Doherty Geological Observatory,
Palisades, NY.

Primary production measurements were made using the 14C technique. Water 
samples were collected before dawn each day from acid-cleaned 20 and 30 
liter Go-Flo sampling bottles. Each sample was inoculated with 9.0 uCi 
sterile NaH14CO3 solution and incubated in 265 ml polystyrene tissue culture 
flasks. New sterile flasks were used for each sample and a teflon liner 
was placed in the cap of each flask prior to incubation. There were four 
replicates at each depth. Dawn to dusk incubations were carried out in 
situ (except for 28 April when we performed a 4 h experiment about local 
noon). The two replicates that were incubated for 24 h were stored in 
an on deck surface water-cooled incubator from dusk to the following dawn. 
After the incubation period the samples were filtered onto Millipore HA 
filters. The filters were then soaked in a few drops of 10% HCl in scintillation 
vials. After 3-4 h, fluor was added, and the samples were counted on the 
ship's Beckman LS 100 scintillation counter. A subsequent count was conducted 
at L-DGO. 

        

The data shows the average of the two replicates for the dawn-to- dusk 
(14 h) (or, in the case of 28 April, the 4 h experiment) and dawn-to-dawn 
incubations. The variation about these replicates is less than 15%. 
		



Sampling methodology and analytical procedures:
Chipman, D.W., J. Marra, T.Takahashi, 1993.  Primary production at 47N and 20W
in the North Atlantic Ocean: a comparison between 14°C incubation method and the
mixed layer carbon budget. Deep-Sea Research II, vol. 40, No. 1/2, pp. 151-169