In September 2023, the SSL@MM (Sea Water Sensing Laboratory @ MIO Marseille, MIO's technical platform), run by Olivier Grosso and Melilotus Thyssen, and recently by Clémentine Gallot (CNRS IR CDD), has celebrated its 4th year of operation and is now part of MIO's shared technical resources. The continuous and gentle pumping of seawater from the Calanque aux Cuivres to taps under laboratory conditions is a success, validated by its almost continuous operation. Similarly, the method of cleaning the seawater inlet pipes is a well-managed routine. The high-frequency, long-term strategy enables the diurnal and seasonal cycles of a coastal marine ecosystem to be studied, and aims to capture the effects of impulse events such as gales, storms and rainfall on phytoplankton communities, certain chemical and hydrological elements, and their transformation products.
So we measure for science and for the community:
- meteorology, available on the OSU weather sitestation installed by Lars-Eric Heimbürger-Boavida and Deny Malengros
- hydrology (STPS temperature and salinity sensors (Fabrice Garcia and Patrick Raimbault), spot sampling of nutrient salts (PAPB platform))
- phytoplankton (observation of functional diversity every two hours) using the automated cytometer at the SSL@MM and PAR (Photosynthetic Available Radiance)
- the production of dissolved oxygen by biological activity thanks to the installation of a MIMS spetrometer (Oliver Grosso, Dominique Lefevre)
Le SSL@MMIt's also about welcoming researchers and training students. To date, we have welcomed four students on work placements, who have been able to study the dynamics of phytoplankton in real time as the seasons and meteorological events change, and two PhD students who have published the data collected in the SSL@MM (Robin Fuchs, Zoé Lebras). As part of more tropical projects such as MAP-IO (ww.map-io.re, Indian Ocean) and HOPE (S. Bonnet, Nouméa), training courses in automated cytometry were given (totalling 7 PhD students/engineers/researchers).
With access to workbenches where seawater is continuously pumped in by gentle peristaltic pumping, requests to install sensors or carry out experiments are multiplying.
We were able to carry out submersion tests on the Cytosub from the ERC HOPE project, which is due to be installed on an intelligent buoy in the Pacific Ocean.
Here are some photos of the first trials. It is now ready to make its first dive into the calanque in December.
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In these photos from November 2023, you can see science in full swing!
From left to right: (a) Victoire Rérolle (Fluidion) testing a pH meter, (b) training by the manufacturer CytoBuoy (Rob Lievaart) on a newly acquired cytometer for the HOPE project (Sophie Bonnet and Matthieu Savarino), (c) maintenance of the automated cytometer (Clémentine Gallot) and (d) installation of two mass spectrophotometers - MIMS (Olivier Grosso).
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In addition, in view of the installation of a cytometer on the PolarPodTo prepare for installation on a platform in the middle of Antarctica, duration tests are carried out on seawater pressure and flow regulators.
Here are just a few examples of events that have been hosted over the last 4 years at the SSL@MM :
- In October 2022, the CYTOEXPERT thematic school on flow cytometry (Gérald Grégori, Maurice Libes) was held in the lab. The various conventional and automated cytometry techniques were demonstrated.
- On a more artistic note, the EIDOLA theatre company came for a residency in September 2023, inspired by the sound of the waves in the calanques and the microscopic marine world. They were able to test drafts of their work on a few Cartesian minds and produced the poster for their show using photos straight out of the continuous cytometer.
- Le SSL@MM was visited by consular representatives as part of "climate diplomacy week", and by a class of Dutch students (Vincent Rossi)
- Validations of protocols for APERO, HOPE, MAPIO, BIOSWOT-Med, concentrations of picoeukaryotes for the LEFE BIOPHYMED, and image analyses for the BIODIVINOV project are all carried out in the SSL@MM.
We will soon be adding a TSG (Isabelle Taupier-Letage, Deny Malengros and the support of the SAM) connected continuously, and a measurement of sea level to complete the HTMNET network (Tathy Missamou, Vincent Rey, J-L Fuda).
Our system is regularly cleaned to limit biofouling, by SAM divers for the underwater strainer every week, with a high-pressure ferret on the outside every month, and chemically on the inside every fortnight, which ensures real measurement of the water in the calanque. Don't hesitate to contact us to carry out your own experiments and test your sensors, as if you were on board a ship (guaranteed no seasickness!). The specifics of the pumping system are also described below. available on our website and seawater stations can be booked on the OSU Pytheas GRR.