Feeling Fine and Sandy!

After a few minor hiccups regarding the mesocosm setup, Adele and I are off to a great start with this research. Adele, a PhD Candidate at University of Goteborg in Sweden, arrived last week after an exhausting day of travel to help me with this final project. As an expert in marine biogeochemistry, particularly in marine sediments, Adele is well-suited to collect the sediment oxygen data for this work. The minor hiccups actually regarded some of the setup for her materials, as Adele traveled with nearly $10,000 of research equipment and one piece wouldn't fit in her luggage so she asked me to build it (thanks dad for the great DIY version). This DIY piece of equipment shown in this week's picture, is meant to hold the micromanipulator so that the oxygen microelectrodes--tiny needle-like sensors that measure oxygen profiles in the mud--can enter the samples vertically. The micromanipulator is then programmed to slowly lower the microelectrodes into the water or sediment (.001 millimeters at a time in some cases) and take measurements at set intervals that are logged by the computer not shown in this picture. By collecting these oxygen measurements, we learn how oxygen availability changes in sediments when microplastics are present and we can also calculate the oxygen penetration depth, the maximum depth that oxygen is available within the sediment. 

In this picture you can also see the luminophores in action, though they look like radioactive material because of their bright green color. On the other side of the environmental chamber, I am taking pictures of each sediment mesocosm after exposing the sediments to UV light and tracking how deep the luminophores travel. These two aspects of the experiment--oxygen penetration and bioturbation--are inherently linked processes and important ecosystem functions provided by the animals that live on or in the sediment. Our goal is to learn how microplastics alter these processes using concentrations of pollution from the field and expected future concentrations.

It has been such a joy working on this project, problem-solving through the bumps in the road, even sitting at the computer to process all these images. Adele and I will be collecting data for one more week and then she will return to Sweden while I finish the last data collection components--more on that in a future blog. Stay tuned, because next week will mark the end of the experiment so you know I will be writing an exciting blog to wrap up this portion of the work.

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