Samples for the first bioassay experiment and ….. troubleshootings ! Eithne Tynan , January 13 , 2013
After a false start yesterday , we managed to sample for the first bioassay experiment at the early hours of this morning . The weather was still looking rough at around 8pm and most of us thought we might have to cancel again . However , slowly the weather seemed to calm down and by 2am there was only a gentle rolling on the ship . Just what we wanted !
Around 1.30 am heads started popping into the labs and by 2.15 everyone was ready to start with all the preparations . As has been explained previously and as in the last two cruises we are trying to look at the effects that different carbon dioxide levels may have on life in the oceans . Similar experiments will be run during this Antarctic cruise with an added factor , iron . The Southern Ocean is what is called an iron limited region , this means that while there might be plenty of other nutrients for phytoplankton to feed and grow on , there is not enough iron , an essential trace element for life , and this limits the growth of biomass . For us this has a very important consequence , we must work under trace metal clean conditions , to avoid any contamination that could induce a response in the phytoplankton , masking the effect of pCO2 that we are interested in looking at . To check we are doing this correctly we are also running some parallel control experiments where we are adding iron to the water . Comparing the two we will be able to quickly see if all our efforts were successful .
The damaged instrument now sits safely in the lab with a high tech protective cover , made of zip-lock bags and duct tape . @ Eithne Tynan
My job on the cruise is to measure the carbonate parameters for the bioassays to confirm that we have achieved the pCO2 levels desired . This is quite an essential task and so the pressure is on when the bioassays starts , all the instruments must be ready and calibrated so we can measure the water sampled immediately . This means it ’ s an even earlier start in the carbonate chemistry lab when there are bioassays as instruments take between two and four hours to be calibrated . We actually had a bit of a bumpy start as one of our instruments got wet while we were setting up in the Falklands , blowing the power supply ! This was
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