FN Archimer Export Format
PT J
TI Sampling in low oxygen aquatic environments: The deviation from anoxic conditions
BT 
AF Garcia‐Robledo, Emilio
   Paulmier, Aurelien
   Borisov, Sergey M.
   Revsbech, Niels Peter
AS 1:1;2:2;3:3;4:4;
FF 1:;2:;3:;4:;
C1 Departamento de Biologia Universidad de Cadiz Cadiz, Spain
   Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS), Université de Toulouse, Centre National de la Recherche Scientifique, Centre National d'Etudes Spatiales, Institut de Recherche pour le Développement Toulouse ,France
   Institute of Analytical Chemistry and Food Chemistry Graz University of Technology Graz ,Austria
   Department of Biology, Aarhus University Centre for Water Technology Aarhus University Aarhus, Denmark
C2 UNIV CADIZ, SPAIN
   UNIV TOULOUSE, FRANCE
   UNIV TECH GRAZ, AUSTRIA
   UNIV AARHUS, DENMARK
IF 3.162
TC 8
UR https://archimer.ifremer.fr/doc/00718/83008/87897.pdf
LA English
DT Article
CR AMOP
BO L'Atalante
AB Studies of the impact of hypoxic or anoxic environments on both climate and ecosystems rely on a detailed characterization of the oxygen (O2) distribution along the water column. The former trivial separation between oxic and anoxic conditions is now often redefined as a blurry concentration range in which both aerobic and anaerobic processes might coexist, both in situ and during experimental incubations. The O2 concentrations during such incubations have often been assumed to be equal to in situ levels, but the concentration was rarely measured. In order to evaluate the actual oxygen concentration in samples collected from low-oxygen environments, a series of measurements were performed on samples collected in the Pacific oxygen minimum zones. Our results show a significant deviation from in situ anoxic conditions in samples collected by Niskin bottles where leakage from the bottle material resulted in O2 concentrations of up to 1 μM. Subsequent sampling further increased the O2 contamination. Sampling and analysis by Winkler method resulted in variable apparent concentrations of 2–4 μM. Two common procedures to avoid atmospheric contamination were also tested: allowing gentle overflow and keeping the sampling bottle submersed in a portion of the sampled water. Both procedures resulted in similar O2 contamination with values of 0.5–1.5 μM when bottles were immediately closed and measurements performed with optical sensors, and 3–4 μM apparent concentration when analyzed by the Winkler method. Winkler titration is thus not suited for analysis of low-O2 samples. It can be concluded that incubation under anoxic conditions requires deoxygenation after conventional sampling. 
PY 2021
PD NOV
SO Limnology And Oceanography-methods
SN 1541-5856
PU Wiley
VL 19
IS 11
UT 000688527500001
BP 733
EP 740
DI 10.1002/lom3.10457
ID 83008
ER

EF