[en] Coccolithophores, among which Emiliania huxleyi is the most abundant and widespread species, are considered the most productive calcifying organism oil earth. The export of organic carbon and calcification are the main drivers of the biological CO2 pump and are expected to change with oceanic acidification. Coccolithophores are further known to produce transparent exopolymer particles (TEP) that promote particle aggregation. As a result, the TEP and biogenic calcium carbonate (CaCO3) contribute to the export of carbon from the surface ocean to deep waters. In this context, we followed the development and the decline of E. huxleyi using batch experiments with monospecific cultures. We studied the link between different processes Such as photosynthesis, calcification and the production of TEP. The onset of calcification was delayed in relation to photosynthesis. The timing and the general feature of the dynamics of calcification were closely related to the saturation state of seawater with respect to calcite, Omega(cal). The production of TEP was enhanced after the decline of phytoplankton growth. After nutrient exhaustion, particulate organic carbon (POC) concentration increased linearly with increasing TEP concentration, suggesting that TEP contributes to the POC increase. The production of CaCO3 is also strongly correlated with that of TEP, suggesting that calcification may be considered as a Source of TEP precursors.
De Bodt, Caroline; Laboratoire d’Océanographie Chimique et Géochimie des Eaux, Faculté des Sciences, Université Libre de Bruxelles, B-1050 Brussels, Belgium
Harlay, Jérôme ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Océanographie chimique
Chou, Lei; Laboratoire d’Océanographie Chimique et Géochimie des Eaux, Faculté des Sciences, Université Libre de Bruxelles, B-1050 Brussels, Belgium
Language :
English
Title :
Biocalcification by Emiliania huxleyi in batch culture experiments
Publication date :
2008
Journal title :
Mineralogical Magazine
ISSN :
0026-461X
eISSN :
1471-8022
Publisher :
Mineralogical Society of Great Britain, London, United Kingdom
Banse, K., Uptake of inorganic carbon and nitrate by marine plankton and the Redfield ratio (1994) Global Biogeochemical Cycles, 8, pp. 81-84
Brown, C.W., Yoder, J.A., Coccolithophorid blooms in the global ocean (1994) Journal of Geophysical Research, 99, pp. 7467-7482
Chisholm, J.R.M., Gattuso, J.-P., Validation of the alkalinity anomaly technique for investigating calcification and photosynthesis in coral reef communities (1991) Limnology and Oceanography, 36, pp. 1232-1239
Dickson, A.G., Sabine, C.L., Christian, J.R., Guide to best practices for ocean CO2 measurements (2007) PICES Special Publication, 3. , 191 pp
Engel, A., Delille, B., Jacquet, S., Riebesell, U., Rochelle-Newall, E., Terbrüggen, A., Zondervan, I., Transparent exopolymer particles and dissolved organic carbon production by Emiliania huxleyi exposed to different CO2 concentrations: A mesocosm experiment (2004) Aquatic Microbial Ecology, 34, pp. 93-104
Gran, G., Determination of the equivalence point in potentiometric titrations - Part II (1952) The Analyst, 77, pp. 661-671
Klaas, C., Archer, D.E., Association of sinking organic matter with various types of mineral ballast in the deep sea: Implications for the Rain Ratio (2002) Global Biogeochemical cycles, 16, pp. 63-1-63-14
Passow, U., Transparent exopolymer particles (TEP) in aquatic environments (2002) Progress in Oceanography, 55, pp. 287-333
Passow, U., Alldredge, A.L., A dye-binding assay for the spectrophotometric measurement of transparent exopolymer particles (TEP) (1995) Limnology and Oceanography, 40, pp. 1326-1335
Schartau, M., Engel, A., Schröter, J., Thoms, S., Völker, C., Wolf-Gladrow, D., Modelling carbon overconsumption and the formation of extracellular particulate organic carbon (2007) Biogeosciences, 4, pp. 433-454
Toggweiler, J., Carbon overconsumption (1993) Nature, 363, pp. 210-211
Van Emburg, P.R., de Jong, E.W., Daems, W.T., Immunochemical localization of a polysaccharide from biomineral structures (coccoliths) of Emiliania huxleyi (1986) Journal of Ultrastructure and Molecular Structure Research, 94, pp. 246-259
Zondervan, I., Zeebe, R.E., Rost, B., Riebesell, U., Decreasing marine biogenic calcification: A negative feedback on rising atmospheric pCO2 (2001) Global Biogeochemical Cycles, 15, pp. 507-516