FN Archimer Export Format
PT J
TI Determination of dissolved organic nitrogen in seawater using Kjeldahl digestion after inorganic nitrogen removal
BT 
AF DOVAL, MD
   FRAGA, F
   PEREZ, FF
AS 1:;2:;3:;
FF 1:;2:;3:;
IF 0.662
TC 16
UR https://archimer.ifremer.fr/doc/00093/20429/18096.pdf
LA English
DT Article
AB An update of the Kjeldahl method is presented for the direct determination of dissolved organic nitrogen (DON) in seawater. Dissolved inorganic nitrogen is previously removed: ammonium as NH3 with NaOH at pH 9.4; and, subsequently, nitrate and nitrite as nitric oxide with FeSO4 in acid medium. The sample is then mineralized to ammonium, which is measured with a Technicon autoanalyzer by the indophenol blue method. The range of recovery for tested standard compounds is similar to those obtained by high temperature oxidation (HTO) techniques. Direct determination of DON by the method described in this work marks an improvement in precision, in comparison with other methods; the standard deviation obtained for samples of seawater is +/-0.2 mu mol.l(-1). The precision of DON measurements is not dependent on dissolved inorganic nitrogen analysis. For several stations in the Northeast Atlantic Ocean, DON values ranged between 3 and 10 mu mol.l(-1).
PY 1997
SO Oceanolica Acta
SN 0399-1784
PU Gauthier-Villars
VL 20
IS 5
UT A1997YB28500005
BP 713
EP 720
ID 20429
ER

EF