@article{fdi:010082746,
  title = {{S}ampling in low oxygen aquatic environments : the deviation from anoxic conditions},
  author = {{G}arcia-{R}obledo, {E}. and {P}aulmier, {A}ur{\'e}lien and {B}orisov, {S}. {M}. and {R}evsbech, {N}. {P}.},
  editor = {},
  language = {{ENG}},
  abstract = {{S}tudies of the impact of hypoxic or anoxic environments on both climate and ecosystems rely on a detailed characterization of the oxygen ({O}-2) distribution along the water column. {T}he 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. {T}he {O}-2 concentrations during such incubations have often been assumed to be equal to in situ levels, but the concentration was rarely measured. {I}n 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 {P}acific oxygen minimum zones. {O}ur results show a significant deviation from in situ anoxic conditions in samples collected by {N}iskin bottles where leakage from the bottle material resulted in {O}-2 concentrations of up to 1 mu {M}. {S}ubsequent sampling further increased the {O}-2 contamination. {S}ampling and analysis by {W}inkler method resulted in variable apparent concentrations of 2-4 mu {M}. {T}wo 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. {B}oth procedures resulted in similar {O}-2 contamination with values of 0.5-1.5 mu {M} when bottles were immediately closed and measurements performed with optical sensors, and 3-4 mu {M} apparent concentration when analyzed by the {W}inkler method. {W}inkler titration is thus not suited for analysis of low-{O}-2 samples. {I}t can be concluded that incubation under anoxic conditions requires deoxygenation after conventional sampling.},
  keywords = {{PACIFIQUE}},
  booktitle = {},
  journal = {{L}imnology and {O}ceanography : {M}ethods},
  volume = {19},
  numero = {11},
  pages = {733--740},
  ISSN = {1541-5856},
  year = {2021},
  DOI = {10.1002/lom3.10457},
  URL = {https://www.documentation.ird.fr/hor/fdi:010082746},
}