Day Three Aboard r/v Kilo Moana

4 September 2010

5:52 pm HST

Aloha!

Donn Viviani and the incubator

We've had another full day of science aboard the Kilo Moana! We met Graduate Student Donn Viviani who explained the ocean acidification experiments that he is working on. He is measuring primary production (photosynthesis) in microbes by bubbling two different known concentrations of carbon dioxide through samples of water collected.  One concentration is 1100 ppm and the other concentration is 387 ppm (atmospheric CO2). The water samples are incubated on deck of the vessel. The question being explored is whether the addition of carbon dioxide will increase primary production.

Brandon Carter and the Flow Cytometer

We also talked with Technician Brandon Carter who is studying the presence of nitrogen-fixing cyanobacteria. He uses a flow cytometer to look at microorganisms one cell at a time. Flow cytometry uses the principles of light scattering , light excitation, and emission of fluorochrome molecules to generate specific multi-parameter data from particles and cells in the size range of 0.5um to 40um diameter. Using the flow cytometer, he is able to differentiate cells and sort them to put on slides or on media to culture at a later time. http://biology.berkeley.edu/crl/flow_cytometry_basic.html

Automatic Titration Machine

Last night, the teacher group collected several water samples off of the CTD to look at the dissolved oxygen content at different depths. As with most scientific experiments there was a certain procedure to be followed. We used glass Erlen Meyer flasks that we rinsed three times with the sample water. Then we overflowed the sample water through the flask with the flask upside down. Next we overflowed the flask right side up and got rid of any air bubbles by bobbing the tubing that the sample water was coming out of up and down in the flask. Then, we overflowed the flask with the sample water, took out the tubing and put the glass stopper on the flask. Last, we added a salt water seal to the stopper to stop any gas flow between the atmosphere and the sample. Today, we used an automatic titration of iodine machine to help find the dissolved oxygen contents of each flask.

I have talked with many of the crew and scientists on board and have asked them how they came to this field of work. Almost all of them expressed an interest in the ocean, being able to problem solve, use their creativity and technical skills. They are, also, enthusiastic and passionate about their work. I've recorded some interviews with some of the technicians and crew that I will be able to share with my students.

We just finished decorating styrofoam cups that are going to be sent down 4800 m with the CTD.  The cups will compress and are a great way of showing the effects of pressure. Atmospheric pressure averages about 14 psi, as compared to the water pressure at 4800 m below the ocean surface, which averages about 6827 psi!

Mrs. Spink