Week one of sampling is complete! The week started by setting up the 9 mesocosms with the desired experimental carbon dioxide (CO2) concentrations. Our experimental design consists of three mesocosms that are being held at 650 ppm of CO2. These will be our controls since the water at Friday Harbor is influenced by strong upwelling and is already high in dissolved CO2. Another three mesocosms are “drift” replicates. The “drift” replicates started with the same CO2 concentration as the controls but we are not making efforts to keep the dissolved CO2 elevated. Finally, we have three mesocosms that are our high CO2 treatment (1200 ppm).
Since the CO2 gradually declines within the controls and high replicates (due to biological activity from planktonic organisms) we analyze our water chemistry samples immediately so that we can inject additional CO2 in an attempt to keep the same pCO2 throughout the experiment.
We spent most of Monday setting up the experiment. Data collection started bright and early Tuesday morning and we are fast approaching our 7th day of sampling. The week was fully of exciting science, data collection, and paper discussions for all the students involved in the apprenticeship.
Occasionally, week 1 was hectic and stressful as the students carefully began their sampling protocols and established individual daily routines for processing data. Several days of rain and strong winds early in the week forced us to establish a “dry” sampling station to prevent digital equipment from being destroyed.
Our team’s work was fortunate to be the highlight of several press releases this week. Our experiment was featured locally on the University of Washington’s website (http://www.washington.edu/news/2013/04/11/space-age-domes-offer-a-window-on-ocean-acidification/), and made international science news on the European Project on Ocean Acidification list-serve (EPOCA; http://oceanacidification.wordpress.com/?s=FHL). We were also interviewed by a journalist from New York as she shadowed our research and daily sampling routines.
The experiment is still in its infancy and we are not sure what patterns and trends are developing within our mesocosms. We are excited to analyze our data since the system we are testing is unique to other mesocosm studies around the world. Friday Harbor waters are already acidified due to upwelling, and we have high nutrient levels. Over the past few days we have identified and described a baseline planktonic community for the Friday Harbor waters (Figures 1 and 2, images were taken with an epiflourescent microscope at 40x). We are excited to start week 2 and are curious to identify how high nutrients, high CO2/low pH conditions may effect planktonic community assemblages, abundance, and biomass. Stay tuned for updates from our 2nd week of sampling!