[en] We studied the direct effects of CO, and related changes in seawater carbonate chemistry on marine planktonic organisms in a mesocosm experiment. In nine outdoor enclosures (similar to 11 m(3) each), the partial pressure of CO2 (pCO(2)) in the seawater was modified by an aeration system. The triplicate mesocosm treatments represented low (similar to 190 parts per million by volume (ppmV) CO2), present (similar to 410 ppmV CO2), and high (similar to 710 ppmV CO2) pCO(2) conditions. After initial fertilization with nitrate and phosphate a bloom dominated by the coccolithophorid Emiliania huxleyi occurred simultaneously in all of the nine mesocosms; it was monitored over a 19-day period, The three CO2 treatments assimilated nitrate and phosphate similarly. The concentration of particulate constituents was highly variable among the replicate mesocosms, disguising direct CO2-related effects. Normalization of production rates within each treatment, however, indicated that the net specific growth rate of E. huxleyi, the rate of calcification per cell, and the elemental stoichiometry of uptake and production processes were sensitive to changes in pCO(2). This broad influence of CO2 on the E huxleyi bloom suggests that changes in CO2 concentration directly affect cell physiology with likely effects on the marine biogeochemistry.
ARMSTRONG, R. A., C. LEE, J. I. HEDGES, S. HONJO, AND S. G. WAKEHAM. 2002. A new, mechanistic model for organic carbon fluxes in the ocean based on the quantitative association of POC with ballast minerals. Deep-Sea Res. II 49: 219-236.
BADGER, M. R., T. J. ANDREWS, S. M. WHITNEY, M. LUDWIG, D. C. YELLOWLEES, W. LEGGAT, AND G. D. PRICE. 1998. The diversity and coevolution of Rubisco, plastids, pyreniods, and chloroplast-based CO2-concentrating mechanisms in algae. Can J. Bot. 76: 973-1002.
BARKER, S., J. A. HIGGINS, AND H. ELDERFIELD. 2003. The future of the carbon cycle: review, calcification response, ballast and feedback on atmospheric CO2. Philos. Trans. R. Soc. Lond. Ser. A361. 1810: 1997-1999.
BREWER, P. G., C. GOYET, AND G. FRIEDERICH. 1997. Direct observation of the oceanic CO2 increase revisited. Proc. Natl. Acad. Sci. USA 94: 8308-8313.
BURKHARDT, S., G. AMOROSO, U. RIEBESELL, AND D. SÜLTEMEYER. 2001. CO2 and HCO3-uptake in marine diatoms acclimated to different CO2 concentrations. Limnol. Oceanogr. 46: 1378-1391.
_, I. ZONDERVAN, AND U. RIEBESELL. 1999. Effect of CO2 concentration on C:N:P ratio in marine phytoplankton: a species comparison. Limnol. Oceanogr. 44: 683-690.
CALDEIRA, K., AND M. E. WICKETT. 2003. Anthropogenic carbon and ocean pH. Nature 425: 365.
CHEN, G.-T., AND F. J. MILLERO. 1979. Gradual increase of oceanic CO 2. Nature 277: 205-206.
DICKSON, A. G. 1981. An exact definition of total alkalinity and a procedure for the estimation of alkalinity and total inorganic carbon from titration. Deep-Sea Res. 28: 609-623.
_. 1990. Thermodynamics of the dissociation of boric acid in synthetic seawater from 273.15 to 318.15 K. Deep-Sea Res. 37: 755-766.
DOLLFUS, D., AND L. BEAUFORT. 1999. Fat neural network for recognition of position-normalised objects. Neural Networks 12: 553-560.
DUGDALE, R. C., AND J. J. GOERING. 1967. Uptake of new and regenerated forms of nitrogen in primary productivity. Limnol. Oceanogr. 12: 196-206.
EGGE, J. K., AND D. L. AKSNES. 1992. Silicate as regulating nutrient in phytoplankton competition. Mar. Ecol. Prog. Ser. 83: 281-289.
ENGEL, A. 2000. The role of transparent exopolymer particles (TEP) in the increase in apparent particles stickiness (α) during the decline of a diatom bloom. J. Plankton Res. 22: 485-497.
_. 2002. Direct relationship between CO2-uptake and transparent exopolymer particles (TEP) production in natural phytoplankton. J. Plankton Res. 24: 49-53.
_, B. DELILLE, S. JACQUET, U. RIEBESELL, E. ROCHELLE-NEWALL, A. TERBRÜGGEN, AND I. ZONDERVAN. 2004a. TEP and DOC production by Emiliania huxleyi exposed to different CO2 concentrations: a mesocosms experiment. Aquat. Microb. Ecol. 34: 93-104.
_, AND U. PASSOW. 2001. The carbon and nitrogen content of transparent exopolymer particles (TEP) derived from diatom exudates. Mar. Ecol. Prog. Ser. 219: 1-10.
_, S. THOMS, U. RIEBESELL, E. ROCHELLE-NEWALL, AND I. ZONDERVAN. 2004b. Polysaccharide aggregation as a potenial sink for marine dissolved organic carbon. Nature 428: 929-931.
EPPLEY, R. W., AND B. J. PETERSON. 1979. Particulate organic matter flux and planktonic new production in the deep ocean. Nature 282: 677-680.
FRANKIGNOULLE, M., A. V. BORGES, AND R. BIONDO. 2001. A new design of equilibrator to monitor carbon dioxide in highly dynamic and turbid environments. Water Res. 35: 1344-1347.
GATTUSO, J.-P., D. ALLEMAND, AND M. FRANKIGNOULLE. 1999. Photosynthesis and calcification at cellular, organismal and community levels in coral reefs: a review on interactions and control by carbonate chemistry. Am. Zool. 39: 160-183.
GERVAIS, F., AND U. RIEBESELL. 2001. Effect of phosphorus limitation on elemental composition and stable carbon isotope fractionation in a marine diatom growing under different CO2 concentrations. Limnol. Oceanogr. 46: 497-504.
GOERIKE, R., AND B. FRY. 1994. Variations of marine plankton δ13C with latitude, temperature, and dissolved CO2 in the world ocean. Glob. Biogeochem. Cycles 8: 85-90.
GRAN, G. 1952. Determination of the equivalence point in potentiometric titration, part II. Analyst 77: 661-671.
HINGA, K. R. 2002. Effects of pH on coastal marine phytoplankton. Mar. Ecol. Prog. Ser. 238: 281-300.
HOUGHTON J. T., AND OTHERS. 2001. Climate change 2001: the scientific basis: contribution of working group I to the third assessment report of the Intergovernmental Panel of Climate Change. Cambridge Univ. Press.
KLAAS, C., AND D. ARCHER. 2002. Association of sinking organic matter with various types of mineral ballast in the deep sea: implications for the rain ratio. Glob. Biochem. Cycles 16. [doi: 10.1029/2001GB001765]
KOROLEFF, F., AND K. GRASSHOF. 1983. Determination of nutrients, p. 125-188. In K. Grasshof, M. Erhardt, and K. Kremling [eds.], Methods of seawater analyses. Verlag Chemie.
LEWIS, E., AND D. WALLACE. 1998. CO2sys Program developed for CO2 system calculations, ORNL/CDIAC-105. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy.
MARI, X., S. BEAUVAIS, R. LEMEE, AND M. L. PEDROTTI. 2001. Non-Redfield C:N ratio of transparent exopolymeric particles in the northwestern Mediterranean Sea. Limnol. Oceanogr. 46: 1831-1836.
PARSONS, T. R., Y. MAITA, AND C. M. LALLI. 1984. A manual of chemical and biological methods for seawater analysis. Pergamon Press, Oxford.
RAVEN, J. A. 1991. Physiology of inorganic C acquisition and implications for resource use efficiency by marine phytoplankton: relation to increased CO2 and temperature. Plant. Cell Environ. 14: 779-794.
REYNAUD, S., N. LECLERCQ, S. ROMAINE-LIOUD, C. FERRIER-PAGES, J. JAUBERT, AND J.-P. GATTUSO. 2003. Interacting effects of CO2, partial pressure and temperature on photosynthesis and calcification in a scleractinian coral. Glob. Change Biol. 9: 1660-1668.
REDFIELD, A. C., B. M. KETCHUM, AND F. A. RICHARDS. 1963. The influence of organism on the composition of sea-water, p. 26-77. In M. N. Hill [ed.], The sea, 2nd ed. Wiley.
RIEBESELL, U., I. ZONDERVAN, B. ROST, P. D. TORTELL, R. ZEEBE, AND F. M. M. MOREL. 2000. Reduced calcification of marine plankton in response to increased atmospheric CO2. Nature 407: 364-367.
RIEGMAN, R., W. STOLTE, A. A. M NOORDELOOS, AND D. SLEZAK. 2000. Nutrient uptake and alkaline phosphatase (APase) activity of Emiliania huxleyi (Prymnesiophyceae) during growth under N and P limitation in continuous cultures. J. Phycol. 36: 87-96.
ROCHELLE-NEWALL, E., AND OTHERS. 2004. Chormophoric dissolved organic matter in experimental mesocosms maintained under different pCO2 levels. Mar. Ecol. Prog. Ser. 272: 25-31.
ROST, B., U. RIEBESELL, S. BURKHARDT, AND D. SÜLTEMEYER. 2003. Carbon acquisition of bloom-forming marine phytoplankton. Limnol. Oceanogr. 48: 55-67.
ROY, R., AND OTHERS. 1993. The dissociation constants of carbonic acid in seawater at salinities 5 to 45 and temperatures 0 to 45°C. Mar. Chem. 44: 249-267.
SACHS, L. 1974. Angewandte Statistik. Springer Verlag.
SCIANDRA, A., J. HARLAY, D. LEFEVRE, R. LEMEE, P. RIMMELIN, M. DENIS, AND J. P. GATTUSO. 2003. Response of coccolithophorid Emiliania huxleyi to elevated partial pressure of CO2 under nitrogen limitation. Mar. Ecol. Prog. Ser. 261: 111-122.
STERNER, R. W., AND J. J. ELSER (EDS.) 2002. Ecological stoichiometry. Princeton Univ. Press.
TORTELL, P. D., G. R. DITULLIO, D. M. SIGMANN, AND F. M. M. MOREL 2002. CO2 effects on taxonomic composition and nutrient utilization in an equatorial Pacific phytoplankton assemblage. Mar. Ecol. Prog. Ser. 236: 37-43.
UPPSTRÖM, L. 1974. The boron-chlorinity ratio of deep seawater from the Pacific Ocean. Deep-Sea Res. 21: 161-163.
URABE, J., TOGARI, J. AND J. J. ELSER 2003. Stoichiometric impacts of increased carbon dioxide on a planktonic herbivore. Glob. Change Biol. 9: 818-825.
VAULOT, D. 1989. CytoPC: processing software for flow cytometric data. Signal Noise 2: 8.
WEISS, R. F. 1974. Carbon dioxide in water and seawater: the solubility of a non-ideal gas. Mar. Chem. 2: 203-215.
WILLIAMS, P. J. LE B., AND J. K. EGGE. 1998. The management and behaviour of the mesocosms. Est. Coast Shelf Sci. 46: 3-14.
ZONDERVAN, I., B. ROST, AND U. RIEBESELL. 2002. Effect of CO2 concentration on the PIC/POC ratio in the coccolithophore Emiliania huxleyi grown under light-limiting conditions and different daylengths. J. Exp. Mar. Biol. Ecol. 272: 55-70.
_, R. E. ZEEBE, B. ROST, AND U. RIEBESELL. 2001. Decreasing marine biogenic calcification: a negative feedback on rising atmospheric pCO 2. Glob. Biogeochem. Cycles 15: 507-516.
