Les radeaux de Stareso…

After 5 days of delay, we finally really start the sampling!! To place the events, last week-end the mesocosms tangled in the ropes and water went out of the bags. We had to re-open the bags wait one night close them again and start the acidification step by step during 3 days. The last acidification was on Saturday and to be on time we had to work late the days before (till 11pm sometime!).

The zodiac with the broken board and motor nearly on the seawater!!

So, yesterday (Time 0) we had the first departure at 4am to sample the processes. Well, in theory was 4am but…Louisa, Anggeliki and Mauro didn’t wake up!! Hopefully they don’t sleep in the lighthouse so, we could wake them up and we left only 15min late. But the teams on the sampling platforms were efficient and we arrived at the quay at 6.30am which was more or less the time expected for this team. Not even the time for a coffee and we prepared the vials for the incubations and other.
Fred and myself (Laure) we had to fill 8 vials of 60mL per mesocosm, inject “heavy water” (it’s water with 18 oxygen) in 5 of them and fixe the 3 others for the initial values. Then we incubate the 5 vials during the light period, phytoplankton will split this marked water to O2 by photosynthesis. Later in the laboratory we’ll be able to quantify the production of marked O2 and the decrease of marked water and so, have the Gross Primary Production data. The incubations are done near the mesocosms at 6 meter depth (half of a mesocosm).
The day wasn’t finish and we had a last important step to do: the addition of few grams of heavy stable Carbon (Carbon 13) which will allow us to follow the Carbon in the community.

The boats we use to go to the working area (=the mesocosms): the kayak; the zodiac and the Mini-Jeanne (and the biggest one is the Marie-Jeanne but we don’t use it).

Stop for the “science” and back to the event of the day: le radeau de la méduse. Yesterday, as a big day we had our first problem with the zodiac. While Vincent and Raquel were coming to the mesocosms to run the CTD (instrument to measure many parameters at the same time directly) the board on which the motor is kept broke!! they managed to join the Mini-Jeanne (the boat of the station) but we can’t use the zodiac anymore! We’ll to do a more extensive use of the kayaks to compensate this lost.

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