Effect of varying calcium concentrations and light intensities on calcification and photosynthesis in Emiliania huxleyi

• DOI: 10.4319/lo.2007.52.5.2285
• Publication Date: 2010-11-16T08:09:19Z
• Authors: Scarlett Trimborn; Gerald Langer; Bjö rn Rost
• Keywords: Emiliania huxleyi; Coccolithophore; Total inorganic carbon; Carbon fixation

Various protective and metabolic functions for coccolithophore calcification have been proposed such as providing a means to supply CO 2 photosynthesis. It has also speculated that helps dissipate excess energy under high irradiance, thereby circumventing photoinhibition. To address these questions, cells of calcifying strain Emiliania huxleyi were grown at three irradiances (30, 300, 800 µmol photons m −2 s −1 ) in combination with four calcium (Ca) concentrations (0.1, 1, 2.5, 10 mmol L leading different degrees the same strain. Growth rates (µ), particulate organic carbon (POC), inorganic (PIC) production well isotope fractionation (p) determined. Photosynthetic O evolution HCO 3 − uptake measured by membrane inlet mass spectrometry (MIMS). The application this multimethod approach provides new information on role E. . Noncalcifying showed POC ones. No differences p observed Ca concentrations. MIMS measurements indicate noncalcifying can photosynthesize efficiently as, or even more than, ones both use main source. ratio photosynthetic relative net fixation did not differ among acclimated 0.1 Ca. These results (1) is involved acquisition, (2) does provide dissipation irradiances.