Dataset: uptake_aa_15N

   PI:              David Kirchman
   of:              University of Delaware (Lewes, Delaware)
   dataset:         Uptake of dissolved free amino acids, 15N uptake,
                    Thymidine production
   dates:           May 20, 1985 to May 28, 1985
   location:        N: 46.9  S: 46.2  W: -18.5  E: -19.9
   Project/cruise:  North Atlantic Bloom Experiment/Atlantis II 119, leg 5
   ship:            R/V Atlantis II

U.S. JGOFS North Atlantic Bloom Experiment (NABE)

Uptake of dissolved free amino acids, 15N uptake and Thymidine production

Prepared by U.S. JGOFS DMO for David Kirchman

N biomass and N uptake by heterotrophic bacteria and phytoplankton were examined during the North Atlantic spring blooom (May 18-31, 1989) aboard the R/V Atlantis II in the vicinity of 47 N, 20 W. The ship followed drifting sediment trap arrays and samples were usually obtained in the morning from CTD/30 litre Niskin rosette casts.

DMO note:
These data lack sufficient metadata to accurately determine sampling location. Data were only reported from a total of 3 sampling locations, and although there were several CTD/Rosette casts done during each of those three days, it is possible through process of elimination to determine the correct station number by matching sampling depths in the bottle data object from this cruise. There are two possible matches for the data reported from 1989-05-20, so the position is estimated from both possible station locations as 46.8333N and 18.347W.

In hopes of making these data more useful, the DMO added metadata to this data object in September 2009, to support geolocation of the data.

date      sta  cast  event     latitude longitude  sampling_activity
19890520  27   5     05200840  46.8333  -18.3467  CTD/Rosette_200m_N-15/micro
or
19890520  27   10    05201930  46.8333  -18.3483  CTD/Rosette_200m_N-15/micro
19890522  29   6     05221617  46.3650  -17.9333  CTD/rosette_1000m_del-N-15
19890528  35   4     05281115  46.3367  -17.8650  CTD/rosette_250m_N-15/micro

For a complete description of methodology, please refer to:
Kirchman, DL, HW Ducklow, JJ McCarthy and C Garside, 1994. Biomass and nitrogen
uptake by heterotrophic bacteria during the spring phytoplankton bloom in the
North Atlantic Ocean. Deep-Sea Research I, Vol.41. No.5/6, pp.879-895

Reference:
Kirchman, DL, HW Ducklow, JJ McCarthy and C Garside, 1994.  Biomass and nitrogen
uptake by heterotrophic bacteria during the spring phytoplankton bloom in the
North Atlantic Ocean.  Deep-Sea Research I, Vol.41. No.5/6, pp.879-895
 
Related data including measured values of heterotrophic bacteria uptake rates of
dissolved free amino acids and 15N, bacteria production measured by the thymidine
method, and a broad array of derived parameters are available as a
downloadable Excel spreadsheet file.