INTERVIEW: Sandra Nunige is an expert in nutrient salt measurements. Here she describes the different analyses she will carry out during the BioSWOT-Med cruise.
THE INSTRUMENTS OF OCEANOGRAPHERS: Sandra Nunige is a chemical engineer at CNRS working at the Mediterranean Institute of Oceanology (MIO) in Marseille. In the BioSWOT-Med campaign she is charge of measuring nutrients concentrations.
What are your research interests in the BioSWOT-Med campaign?
I am involved in the BioSWOT-Med project for the determination of nutrients that allow the growth of phytoplankton in seawater. This project is of particular interest to me because it will allow me to sample near eddies and to make the link with the images obtained by the SWOT satellite.
The time of year corresponds to the spring bloom of phytoplankton with low nutrient concentrations. It will be interesting to use the automated nanomolar phosphate measurement technique recently developed in the laboratory at MIO.
You are responsible for measuring nutrients. What instruments do you use to measure them?
As a specialist in nutrient salt measurements, I will perform measurements of nitrate, nitrite, phosphate, silicate, ammonium, and determine the nitrogen and phosphorus content of particulate and dissolved organic matter.
Samples will be collected on rosette CTDs or by the pumping system and then analyzed directly with an auto-analyzer.
Samples will also be taken for more sensitive measurements of phosphates at nanomolar concentrations using the Liquid Waveguide Capillary Cell protocol.