This technical platform allows the measurement of parameters of the carbonate chemistry (pH, total alkalinity) as well as other important parameters (oxygen, calcium) in order to conduct our research on the impact of ocean acidification.
The technical platform for biogeochemical analyzis is composed of two spectrophotometers (Cary60, Agilent) for measuring the pH of seawater. The analysis method is based on the use of a pH-sensitive dye, purified m-cresol. A spectrophotometer remains permanently in the lab in order to carry out routine measurements (eg: for SOMLIT) while the second can be carried. We also have two potentiometric titrators (Metrohm) allowing the measurement of dissolved oxygen and calcium, these two titrators can be used either in the laboratory or during a campaign at sea. The technical platform is regularly enriched with new techniques of measurement and new instruments. The measurement of the carbonate concentration in seawater by spectrophotometry is under development. In the same way, we eventually plan to be able to quantify very precisely the magnesium concentration of seawater by potentiometric dosing.