1. Impact of the variations of pCO2 on coccolithophorid Emiliania huxleyi during a mesocosm bloom experiment and its directcontribution to carbon export Sollberger, S. (2009) Unit de chimie ocanographiqueee Universit de Li`geee

2. IntroductionMethods Results Discussion ReferencesContents 1 Introduction Storage and release Ocean acidication2 Methods Experimental framework Modeling Statistics3 ResultsCalibrationCalcication4 DiscussionNew calibrated versionImpact on marine calcication2 / 20 3. Introduction Methods Results Discussion ReferencesINTRODUCTION3 / 20 4. Introduction MethodsResults Discussion ReferencesCO2 storage and release 4 / 20 5. Introduction MethodsResults DiscussionReferencesExperimental resultsCalcicationDierent experimental frameworks: acid/base addition, gas injection,etc.Dierent expressions: PIC:POC, PIC:Chla, PIC production, TAcor , etc.Dierent results: from reduced to enhanced calcication under highpCO2Methods Calcication rate AuthorsAcid/base addition Riebesell et al. (2000)Acid/base addition Zondervan et al. (2001)Acid/base addition Zondervan et al. (2002)Gas delivery Sciandraet al. (2003)Air bubbling Engelet al. (2005)Air bubbling Delille et al. (2005)Air bubbling Iglesias-Rodriguezet al. (2008)Air bubbling Bellerbyet al. (2008)Gentle air bubbling Fenget al. (2008) 5 / 20 6. Introduction Methods Results Discussion ReferencesObjectivesTo calibrate a model to dierent pCO2 sTo test the eect of pCO2 on calcication6 / 20 7. Introduction Methods Results Discussion ReferencesMETHODS7 / 20 8. IntroductionMethodsResultsDiscussion ReferencesExperimental frameworkhttp://peece.ifm-geomar.de/images/raft1mi.jpgConditionsAtmosphere @ 180, 410 and 710 atmInduced bloomDaily sampling 8 / 20 9. Introduction MethodsResultsDiscussion ReferencesCoccolithophore modelAdapted from Joassin (2006)9 / 20 10. IntroductionMethods ResultsDiscussion ReferencesTable Look-Up test Adapted test: considers sample of small size in contrast to others, e.g.ANOVACalcicationPIC:CellPIC:ChlaTAcor :CellTAcor :Chla ValidationNormal distributionEquality of the variances Prerequisites often omitted10 / 20 11. Introduction Methods Results Discussion ReferencesRESULTS 11 / 20 12. Nutrients 13. Calcication 14. Introduction Methods Results Discussion ReferencesSignicant similitudes or dierencesM2 M3 M4M5 M6 M7 M8 M9 M1 M2 M3PIC:Cell M4 M5 M6 M7 M8M2 M3M4 M5 M6 M7 M8 M9 M1 M2 M3PIC:Chla M4 M5X M6 M7 M8Gray boxes illustrate a valid test 14 / 20 15. Introduction Methods Results Discussion ReferencesDISCUSSION 15 / 20 16. IntroductionMethods Results Discussion ReferencesModelingNew calibrated version More stable than the old versionAdapted to this experimentNo currently tested as a prediction tool16 / 20 17. IntroductionMethods Results Discussion ReferencesIs calcication reduced under high CO2 ?Impact of pCO2No signicant dierences on calcication between mesocosmsVariations of calcication in a same treatment ImprovementsExperimental design Gentle adaptation Variations in temperature, irradiance, etc. Longer scale processesStatistics Dynamic system High nutrients input17 / 20 18. IntroductionMethodsResultsDiscussionReferencesReferences I Bellerby, R. G. J., Schulz, K. G., Riebesell, U., Neill, C., Nondal, G., Heegaard,E., Johannessen, T., and Brown, K. R. (2008). Marine ecosystemcommunity carbon and nutrient uptake stoichiometry under varying oceanacidication during the PeECE III experiment. Biogeosciences, 5:15171527.Delille, B., Harlay, J., Zondervan, I., Jacquet, S., Chou, L., Wollast, R.,Bellerby, R. G. J., Frankignoulle, M., Borges, A. V., Riebesell, U., andGattuso, J.-P. (2005). Response of primary production and calcication tochanges of pCO2 during experimental blooms of the coccolithophoridEmiliania huxelyi. Global Biogeochem. Cycles,19:doi:10.1029/2004GB002318.Engel, A., Zondervan, I., Aerts, K., Beaufort, L., Benthien, A., Chou, L.,Delille, B., Gattuso, J.-P., Harlay, J., Heemann, C., Homann, L., Jacquet,S., Nejstgaard, J., Pizay, M.-D., Rochelle-Newall, E., Schneider, U.,Terbrggen, A., and Riebesell, U. (2005). Testing the direct eect of CO2 uconcentration on a bloom of the coccolithophorid Emiliania huxleyi inmesocosm experiments. Limnol. Oceanogr., 50(2):493507. 18 / 20 19. IntroductionMethodsResultsDiscussionReferencesReferences II Feng, Y., Warner, M. E., Zhang, Y., Sun, J., Fu, F.-X., Rose, J. M., and Hutchins, D. A. (2008). Interactive eects of increased pCO2 , temperature and irradiance on the marine coccolithophore Emiliania huxleyi (Prymnesiophyceae). Eur. J. Phycol., 43(1):8798.Iglesias-Rodriguez, M. D., Halloran, P. R., Rickaby, R. E. M., Hall, I. R., Colmenero-Hidalgo, E., Gittins, J. R., Green, D. R. H., Tyrell, T., Gibbs, S. J., von Dassow, P., Rehm, E., Armbrust, E. V., and Boessenkool, K. P. (2008). Phytoplankton calcication in a high-CO2 world. Science, 320:336340.Joassin, P. (2006). A 0D coupled biogeochemical model developped for the study of an experimental bloom of Emiliania huxleyi coccolithophorid phytoplankton. Master thesis, University of Liege.Riebesell, U., Zondervan, I., Rost, B., Tortell, P. D., Zeebe, R. E., and Morel, F. M. M. (2000). Reduced calcication of marine plankton in response to increased atmospheric CO2 . Nature, 407:364367.19 / 20 20. IntroductionMethods ResultsDiscussion ReferencesReferences III Sciandra, A., Harlay, J., Lefevre, D., Lem, R., Rimmelin, P., Denis, M., and e Gattuso, J.-P. (2003). Response of coccolithophorid Emiliania huxleyi to elevated partial pressure of CO2 under nitrogen limitation. Mar. Ecol. Prog. Ser., 261:111122.Zondervan, I., Rost, B., and Riebesell, U. (2002). Eect of CO2 concentration on the PIC/POC ratio in the coccolithophore Emiliania huxleyi grown under light-limiting conditions and dierent day lengths. J. of Exp. Mar. Biol. and Ecol., 272:5570.Zondervan, I., Zeebe, R. E., Rost, B., and Riebesell, U. (2001). Decreasing marine biogenic calcication: A negative feedback on rising atmospheric pCO2 . Global Biogeochem. Cycles, 15:507516.20 / 20