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Thesis Reference Thesis Continental scale cyanobacterial dynamics under global warming and eutrophication MANTZOUKI, Evanthia Abstract On-going global warming and eutrophication are expected to promote cyanobacterial dominance worldwide. Although increased lake temperature and nutrients are well-established drivers of blooms, the mechanisms that determine cyanobacterial biomass are complex, with potentially direct, indirect and interactive effects. Cyanobacteria can produce toxins that constitute a considerable risk for animal and human health. Such global range phenomena should be studied at a wide spatial scale, to directly compare phytoplankton response in different lake types across contrasting climatic zones. During this dissertation, the European Multi-lake survey (EMLS) was organised in order to sample lakes across Europe and disentangle the effect of environmental stressors on potentially toxic cyanobacterial blooms. The results demonstrated that the distribution of cyanobacterial toxins and the toxic potential in lakes was highly dependent on direct and indirect effects of temperature. Nutrients interacted synergistically with increased lake temperatures to promote cyanobacterial growth more than that of other phytoplankton taxa. Providing [...] Reference MANTZOUKI, Evanthia. Continental scale cyanobacterial dynamics under global warming and eutrophication. Thèse de doctorat : Univ. Genève, 2018, no. Sc. 5275 DOI : 10.13097/archive-ouverte/unige:112209 URN : urn:nbn:ch:unige-1122091 Available at: http://archive-ouverte.unige.ch/unige:112209 Disclaimer: layout of this document may differ from the published version. 1 / 1 UNIVERSITÉ DE GENÈVE FACULTÉ DES SCIENCES Section des Sciences de la Terre et de l’Environnement Département F.-A. Forel des Sciences Professeur Dr. Bastiaan W. Ibelings de l’Environnement et de l’Eau Institut des Sciences de l’Environnement Continental Scale Cyanobacterial Dynamics under Global Warming and Eutrophication THÈSE présentée à la Faculté des Sciences de l’Université de Genève pour obtenir le grade de Docteur ès sciences, mention sciences de l’environnement par Evanthia MANTZOUKI de Thessalonique (Grèce) Thèse N° 5275 GENÈVE Atelier d’impression ReproMail l’ Université de Genève 2018 1 Table of Contents RÉSUMÉ ......................................................................................................................... 5 CHAPTER 1 .................................................................................................................... 8 The principle and value of the European Multi Lake Survey ....................................... 8 Abstract ................................................................................................................................. 9 Introduction .......................................................................................................................... 9 Technological progress ....................................................................................................... 11 Scientific Responsibility .................................................................................................... 11 Research Questions ............................................................................................................ 13 Acknowledgements ............................................................................................................ 16 CHAPTER 2 .................................................................................................................. 17 Understanding the key ecological traits of cyanobacteria as a basis for their management and control in changing lakes ................................................................ 17 Abstract ............................................................................................................................... 18 Introduction ........................................................................................................................ 19 Cyanobacteria and their key traits ..................................................................................... 23 Functional classification of cyanobacteria ........................................................................ 25 Conclusions and research perspectives ............................................................................. 35 Acknowledgments .............................................................................................................. 36 CHAPTER 3 .................................................................................................................. 37 A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins ........................................................................................... 37 Abstract ............................................................................................................................... 38 Background and summary ................................................................................................. 38 Methods ............................................................................................................................... 40 Data records ........................................................................................................................ 48 Technical validation ........................................................................................................... 49 Data citations ...................................................................................................................... 50 Acknowledgements ............................................................................................................ 52 Author contributions .......................................................................................................... 52 CHAPTER 4 .................................................................................................................. 53 2 A European Multi Lake Survey in one of the hottest summers on record: cooler Boreal regions develop bigger blooms than warmer Mediterranean regions ............. 53 Abstract ............................................................................................................................... 54 Introduction ........................................................................................................................ 55 Materials & Methods .......................................................................................................... 57 Results ................................................................................................................................. 61 Discussion ........................................................................................................................... 70 Acknowledgements ............................................................................................................ 78 Supporting material ............................................................................................................ 78 CHAPTER 5 .................................................................................................................. 84 Temperature effects explain continental scale distribution of cyanobacterial toxins ...................................................................................................................................... 84 Abstract ............................................................................................................................... 85 Introduction ........................................................................................................................ 86 Results ................................................................................................................................. 88 Discussion ........................................................................................................................... 96 Materials & Methods ........................................................................................................ 101 Supplementary Material .................................................................................................. 107 Acknowledgements .......................................................................................................... 107 Author Contributions ....................................................................................................... 107 CHAPTER 6 ................................................................................................................ 108 Opinion: Multi-lake snapshot surveys for lake monitoring, more than a shot in the dark ............................................................................................................................. 108 Abstract ............................................................................................................................. 109 Introduction - why do we monitor? ................................................................................. 110 Different monitoring strategies ....................................................................................... 110 Advantages of the MLSS .................................................................................................. 112 Conclusions ....................................................................................................................... 115 Abbreviations ..................................................................................................................
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