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Parameterisation of Microprotozooplankton Grazing and Growth Parameterisation of Microprotozooplankton Grazing and Growth: From data analysis to simulations in ecosystem model coupled to general circulation-biogeochemical model. Dissertation Zur Erlangung des Akademischen Grades eines Doktors der Naturwissenschaften - Dr. rer. Nat. – Im Fachbereich 2 (Biologie/Chemie) Der Universität Bremen vorgelegt von Sévrine Sailley Institutes: Alfred Wegener Institut for Polar and Marine Research (AWI), Bremerhaven, Germany University of East Anglia (UEA), Norwich, UK British Antarctic Survey (BAS), Cambridge, UK University Bremen, Germany This work was funded by Euroceans program, project number WP3.2-SYS-1092. 2 Erster Gutachter: Prof. Dr. Dieter Wolf-Gladrow Zweiter Gutachter: Prof. Dr. Corinne Le Quéré Tag des öffentlichen Kolloquims: Universität Bremen, 23 November 2009 Eidesstattliche Erklärung Hiermit erkläre ich nach § 6 Abs. 5 der Promotionsordnung der Uni Bremen (vom 14 März 2007), dass ich die Vorliegende Dissertation (1) ohne unerlaubte Hilfe angefertigt habe, (2) keine anderen als die von mir angegebenen Quellen und Hilfsmittel benutzt habe und (3) die den benutzen Werken wörtlich oder inhaltlich entnommen Stellen als solche kenntlich gemacht habe Sévrine Sailley 3 4 Acknowledgments Here, I would like to thank people who helped me in different ways through this thesis. There are quite a lot of people who should figure here, so if I’ve forgotten somebody, I’m sorry it wasn’t on purpose. Thanks to Christine and Dieter for welcoming me at AWI and in Bremerhaven and helping not just with the thesis but also simply life in Germany, thanks for being more than just supervisors. Thanks to Clare Enright for helping me arrange my stay at BAS, but also with going through all the bugs that happened in PlankTOM, or simply little problems with the cluster. Thank you Roisin for the discussions, shared complaints and exchange of idea about everything and nothing while I was at BAS and after. Thanks Corinne for the brainstorming on different occasions, integrating me in the Green Ocean Project, and making me feel welcome in the UK. I think I need to find this book you mentioned once about how people think and how to best communicate with them. Thanks Erik for helping me with every problem I had with the model, I’m not sure I’d have made it to the end otherwise. Thanks to all the friends I’ve made in Germany; Delphine for sharing her office with me at the beginning and helping me adjust to Germany; Joao, Fabi, Gustavo for great parties and fun time (I won’t forget the little Portuguese I learned); Sven, well I don’t know what to say, there’s a lot of thanks in here for you. And the friend in the UK, Marie-Pierre, Roisin, Meike sorry but I’m running out of words. Special thanks to Lys who had to deal with me in the last year of the thesis, not the best one I daresay. So even though you broke the deal you’ll have your blue footed booby. Thanks to Reza who supported me through the whole thing without any complaints, without you I think I would have simply given up. Et aussi merci à ma famille pour m’avoir soutenue dans cette experience. 5 6 7 Table of content ABSTRACT............................................................................................................................................................ 11 ZUSAMMENFASSUNG........................................................................................................................................ 13 CHAPTER 1: INTRODUCTION........................................................................................................................... 17 1- MARINE BIOGEOCHEMISTRY AND CLIMATE............................................................................................... 17 2- THE PELAGIC COMMUNITIES AND THE BIOLOGICAL PUMP........................................................................ 19 3- MICROZOOPLANKTON ................................................................................................................................21 4- BIOGEOCHEMICAL OCEAN GENERAL CIRCULATION MODELS (BOGCMS)............................................ 24 5- AIM OF THE THESIS ..................................................................................................................................... 25 6- THESIS OUTLINE .......................................................................................................................................... 25 7- CONTRIBUTIONS.......................................................................................................................................... 27 8- REFERENCES................................................................................................................................................ 28 CHISHOLM, SW (2000) OCEANOGRAPHY: STIRRING TIMES IN THE SOUTHERN OCEAN. NATURE, 407:685-687 29 CHAPTER 2: PELAGIC CILIATE FEEDING BEHAVIOUR AND GROWTH RATE. AN ANALYSIS BASED ON LABORATORY EXPERIMENTS........................................................................................................................... 33 1-INTRODUCTION............................................................................................................................................. 33 2- DATA AND METHOD ..................................................................................................................................... 35 2.1- Data selection and acquisition............................................................................................................. 35 2.2- Modelling the functional response ....................................................................................................... 38 2.3- Correction for temperature effects and estimation of Q10 .................................................................... 41 3- RESULTS ...................................................................................................................................................... 42 3.1- Q10 estimate for grazing and growth.................................................................................................... 42 3.2- Functional response ............................................................................................................................. 45 3.3- Gross Growth Efficiency (GGE) .......................................................................................................... 53 4-DISCUSSION .................................................................................................................................................. 57 4.1- Temperature effects.............................................................................................................................. 57 4.2- Functional response and GGE............................................................................................................. 57 5- CONCLUSION ............................................................................................................................................... 59 6-REFERENCES ................................................................................................................................................ 61 CHAPTER 3: HETEROTROPHIC DINOFLAGELLATE FEEDING BEHAVIOUR AND GROWTH RATES. AN ANALYSIS BASED ON LABORATORY RESULTS. .............................................................................................. 67 1- INTRODUCTION............................................................................................................................................ 67 2- DATA AND METHOD .................................................................................................................................... 68 2.1- Data selection and acquisition............................................................................................................. 68 2.2- Modelling the functional response ....................................................................................................... 71 2.3- Correction for temperature effects and estimation of Q10 .................................................................... 73 3-RESULTS ....................................................................................................................................................... 74 3.1- Temperature ......................................................................................................................................... 74 3.2- Size and prey PFT impact .................................................................................................................... 75 3.3- Gross Growth Efficiency (GGE) .......................................................................................................... 84 3.4- Comparison with ciliates...................................................................................................................... 85 4- DISCUSSION.................................................................................................................................................. 90 4.1- Functional response ............................................................................................................................. 90 4.2- Prey selection....................................................................................................................................... 91 4.3- Comparison to ciliates ......................................................................................................................... 92 4.4- Impact on food
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