Phytoplankton Community and Abundance in High CO2 Conditions

Abstract

Deleterious effects of anthropogenic carbon dioxide are not yet fully understood at ecosystem or food web level. A large volume mesocosm experiment conducted in Friday Harbor, Washington aimed to research the effects of increased pCO2 levels (650 ppm maintained, 1250 ppm maintained, and 1250 ppm drift) on phytoplankton communities to better understand the future ocean acidifications conditions. Research was focused on effects of pCO2 treatments on phytoplankton densities, genera composition, and correlations between dominant genera and pCO2 treatments. Phytoplankton densities were analyzed for three treatments of pCO2 over a 22-day experiment. No significant difference was found in phytoplankton densities among treatments or genus composition due to variability within treatments. However, it was found that a distinct phytoplankton community shift occurred in all treatments during the experiment due to natural variations in the ecosystem.