Present address and author for reprint requests: MSRC, SUNY, Stony Brook, New York 11794–5000.
SOURCES OF INORGANIC CARBON FOR PHOTOSYNTHESIS BY THREE SPECIES OF MARINE DIATOM1
Article first published online: 28 JUN 2008
Journal of Phycology
Volume 33, Issue 3, pages 433–440, June 1997
How to Cite
Korb, R. E., Saville, P. J., Johnston, A. M. and Raven, J. A. (1997), SOURCES OF INORGANIC CARBON FOR PHOTOSYNTHESIS BY THREE SPECIES OF MARINE DIATOM. Journal of Phycology, 33: 433–440. doi: 10.1111/j.0022-3646.1997.00433.x
Received 5 July 1996. Accepted 23 December 1996.
- Issue published online: 28 JUN 2008
- Article first published online: 28 JUN 2008
- Key index words: Chaetoceros calcitrans;
- Ditylum brightwellii;
- inorganic carbon assimilation;
- isotopic disequilibrium;
- Skeletonema costatum;
- stable carbon isotopes
The utilization of inorganic carbon by three species of marine diatom, Skeletonema costatum (Grev.) Cleve. Ditylum brightwellii (West) Grun., and Chaetoceros calcitrans Paulsen was investigated using an inorganic carbon isotopic disequilibnum technique and inorganic carbon dose-response curves. Stable carbon isotope data of the diatoms are also presented. Observed rates of photosynthetic oxygen evolution were greater than could be accounted for by the theoretical rate of CO2 supply from the uncatalyzed dehydration of HCO3− in the external medium, suggesting use of HCO3− as an inorganic carbon source. Data from the isotopic disequilibrium experiment demonstrate the use of both HCO3− and CO2 for photosynthesis. Carbon isotope discrimination values support the use of HCO3− by the diatoms.