The Incubator used for oxic/anoxic oscillations experiments
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We develop different types of experimental approaches in order to reproduce in vitro particular environmental conditions
and follow the resulting biogeochemical processes. We recently studied the biogeochemistry of estuarine fluid mud during
oxic/anoxic oscillations, using a specially designed incubator. Oxic or anoxic conditions are maintained by
purging the system with air or N2. Oxygen, Temperature and pH as well as the partial pressure of CO2
and CH4 in the gas phase are monitored continuously. Aliquots for any chemical species can also be sampled.
We conducted some experiments for major redox species with fluid mud samples from the Gironde. The system is now with
David Amouroux at the LCABIE (University of Pau) to investigate the mercury transformations during redox oscillations.
Time course of pH, pCO2 and pCH4 during the first 12 days of an oxic/anoxic experiment with a
fluid mud from the Gironde estuary. The whole experiment lasted 32 days with 2 more oxic and anoxic periods.
Major redox species were also followed and gave interesting information on transient diagenesic processes, particularly
those involving carbon, nitrogen and manganese. A paper is in preparation with the whole dataset (Commarieu et al. "almost ready for
submission")
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