Mitigating ocean acidification: Towards a model relating pCO2, irradiance, and density of Zostera marina L. (Eelgrass) from Padilla Bay, WashingtonPacific Estuarine Research Society, PERS/CAERS 2017 Annual Meeting (2017)
In the Salish Sea, the magnitude of ocean acidification varies greatly due to CO2 enrichment from upwelling and CO2 uptake by primary producers. Eelgrass meadows have been identified as potential mitigators of ocean acidification because eelgrass takes up dissolved CO2 and bicarbonate through photosynthesis, is carbon limited, and can increase its photosynthetic rate under elevated pCO2conditions. However, eelgrass morphology and density varies from site to site in the Salish Sea, and photosynthesis varies diurnally. In this study, we experimentally investigated the effect of eelgrass shoot density and irradiance on eelgrass’ ability to alter carbonate chemistry under conditions of moderate and high pCO2. We found no difference in carbon drawdown rate between pCO2 treatments. However, increasing shoot density led to greater increases in pH, but only up to a point. Above a threshold shoot density, the increase in pH was not as high, possibly due to self-shading. In the absence of light, eelgrass density decreased pH, most likely due to cellular respiration. These results imply that eelgrass may exacerbate ocean acidification if light is limiting. We propose further study of eelgrass density under a gradation of irradiance levels. By quantifying the changes in carbonate chemistry due to varying eelgrass densities and varying irradiances, our research will help identify characteristics of eelgrass habitats that could provide refugia for marine organisms from ocean acidification.
- Ocean acidification
Publication DateMarch 7, 2017
Citation InformationTyler Tran, Brooke Love, Sylvia Yang and Cinde Donoghue. "Mitigating ocean acidification: Towards a model relating pCO2, irradiance, and density of Zostera marina L. (Eelgrass) from Padilla Bay, Washington" Pacific Estuarine Research Society, PERS/CAERS 2017 Annual Meeting (2017)
Available at: http://works.bepress.com/brooke-love/11/