The combined effect of global warming and ocean acidification on the coccolithophore Gephyrocapsa oceanica carbon production and physiology

• Main Author: Sett, Scarlett
• Format: Thesis
• Language: English
• Published: 2010
• Subjects: Course of study: MSc Biological Oceanography; Ocean acidification
• Online Access: https://oceanrep.geomar.de/id/eprint/11486/; https://oceanrep.geomar.de/id/eprint/11486/2/SSett_MasterThesis2010.pdf

Climate change is expected to impact oceanic ecosystem functioning in the upcoming decades, ocean acidification and global warming being the most important factors which will shape the future ocean dynamics (Jackson 2008). In the experiments presented here we used an innovative approach that consisted of extending the number of treatments across a wide range of carbon dioxide partial pressure (pCO2) levels and two temperatures which allowed to test lower and upper thresholds of biological production. Growth, calcification and POC production rates showed an optimum curve response to increasing pC02, with an almost doubling in production rates at 20CC and opt imum rates for pCO2 levels of ~290-599 μatm at 15CC and ~488-1052 μatm pCO2 at 20CC. PIC and POC cellular quotas showed changes to increasing pCO2 but no effect from increasing temperature. Results obtained from the combined effect of global warming and increasing pCO2 from these experiments might contribute to shape biogeochemical modeling formulations in the near future.