The suitability of Mytilus edulis as proxy archive and its response to ocean acidification [Elektronische Ressource] = Die Eignung von Mytilus edulis als Proxy-Archiv und deren Reaktion auf Ozeanversauerung / vorgelegt von Agnes Heinemann

The suitability of Mytilus edulis as proxy archive
and its response to ocean acidification

Die Eignung von Mytilus edulis als Proxy-Archiv

und deren Reaktion auf Ozeanversauerung

















Dissertation
zur Erlangung des Doktorgrades
der Mathematisch-Naturwissenschaftlichen Fakultät
der Christian-Albrechts-Universität zu Kiel

vorgelegt von Agnes Heinemann
Kiel 2011
The suitability of Mytilus edulis as proxy archive
and its response to ocean acidification

Die Eignung von Mytilus edulis als Proxy-Archiv
und deren Reaktion auf Ozeanversauerung














Dissertation
zur Erlangung des Doktorgrades
der Mathematisch-Naturwissenschaftlichen Fakultät
der Christian-Albrechts-Universität zu Kiel

vorgelegt von Agnes Heinemann
Kiel 2011























Referent: Prof. Anton Eisenhauer
Korreferent/in: Prof. Frank Melzner
Tag der mündlichen Prüfung: 15.04.2011
Zum Druck genehmigt: Kiel,

gez.




Für Mama und Paps










Die Gelassenheit, alles das hinzunehmen, was nicht zu ändern ist.
Die Kraft, zu ändern, was nicht länger zu ertragen ist.
Die Weisheit, das eine vom anderen zu unterscheiden.

(nach R. Niebuhr)Contents

List of Figures I
List of Tables III
Abstract IV
Zusammenfassung VI
Introduction 1
I.1 Ocean Acidification and the Baltic Sea 1
I.2 Marine organisms and their responses to Ocean Acidification 4
I.3 Possible pathways and processes of Biomineralization 7
I.4 The blue mussel - Mytilus edulis 11
I.5 Can bivalve shells tell the past and show the future? 13
I.6 Research questions and outline of the thesis 16
I.7 Experimental setup 18
References 20
Chapter 1 32
Disentangling the Biological and Environmental Control of M. edulis Shell Chemistry
1.1 Abstract 33
1.2 Introduction 34
1.3. Materials and Methods 35
1.3.1 Culturing 35
1.3.2 Sample preparation 36
1.3.3 Analytical methods 36
1.4 Results and Discussion 39
1.5 Conclusions 42
Acknowledgments 43
References 43



Chapter 2 45
The impacts of seawater carbonate chemistry on biomineralization and elemental
concentrations of Mytilus edulis body fluids and its potential as a proxy archive
2.1 Abstract 46
2.2 Introduction 47
2.3 Material and Methods 49
2.3.1 General Setup 49
2.3.2 Experiment 1 50
2.3.3 Experiment 2 51
2.4 Results and Discussions 52
2.4.1 Calcification 53
2.4.1.1 Calcification rates 53
2.4.1.2 Shell length growth 55
2.4.1.3 Internal shell dissolution 58
2.4.2 Elemental composition of body fluids 61
2+ 2+ 2+2.4.3 Ca , Mg or Sr concentrations 62
2.5 Conclusions 67
References 68
Supplement 74
Chapter 3 78
Boron isotope ratio determination in carbonates via LA-MC-ICP-MS using soda-lime glass
standards as reference material
3.1 Abstract 79
3.2 Introduction 80
3.3 Experimental 81
3.3.1 Standard and sample preparation 81
3.3.2 Instrumentation, data acquisition and evaluation 82
3.4 Results and discussion 85
3.4.1 Standards 85
3.4.2 Coral samples 87
3.5 Conclusions 89
Acknowledgements 90
References 90
Chapter 4 93
Responses of Mytilus edulis extracellular body fluids and shell composition to decreased pH:
11acid-base status, trace elements and  B
4.1 Abstract 94
4.2 Introduction 95
4.3 Material and methods 97
4.3.1 Culture and samples 97
4.3.1.1 General setup 97
4.3.1.2 Experiment 1 98
4.3.1.3 Experiment 2 100
4.3.2 Analytical methods 100
4.4 Results and Discussion 102
4.4.1 Water parameters 102
4.4.2 Acid-base parameters of fluid samples (experiment 1) 102
4.4.3 Elemental ratios of extrapallial fluid and water (experiment 2) 107
114.4.4 Boron isotope (  B) data of M. edulis shells (experiment 2) 110
4.5 Conclusions 113
Acknowledgments 114
References 114
Supplement 121
Summary and Conclusions 125
Outlook 128
References 129
Danksagung 131
Erklärung 132
Curriculum Vitae 133

List of Figures
Figure I.1: Bjerrum Plot and relative distribution of carbon species at today’s surface seawater pH 1

Figure I.2: Concentrations of carbon species, pH and CaCO saturation states of average surface 3
seawater for rising pCO concentrations during different geological times 2 2

Figure I.3: Pictures and SEM images of the inner surface (nacre) of shells from low and high pCO 2
treatment 6

Figure I.4: Modified schematic anatomy of a bivalve 10

Figure I.5: Mytilus edulis (Linné 1758) 11

Figure I.6: SEM-picture of shell layer from Mytilus edulis 12

Figure I.7: Map of Kiel Fjord 18

Figure I.8: Scheme and picture of the experimental setup 19

Figure 1.1: Growth of mussels since start of experiment 37

Figure 1.2: Scheme of values used for calculations of the relative contribution of individual
differences, physiological variability, salinity and temperature to the overall variance of elemental
ratios 38

Figure 1.3: a) Mg/Ca and b) Sr/Ca ratios of the different salinity treatments in comparison to
temperature 39

Figure 1.4: Temperature effects on Mg/Ca ratios and influence of salinity during constant temperature
treatment 40

Figure 1.5: Temperature effects on Sr/Ca ratios and influence of salinity during constant temperature
treatment 40

Figure 1.6: Influence of individual differences, physiological state, salinity and temperature on Mg/Ca
(a) and Sr/Ca ratios (b) in the prismatic layer of M. edulis shells 42

Figure 2.1: Mean calcification rates in the different treatments 53

Figure 2.2: Calcification rates over time 54

Figure 2.3: Mean increment growth during experiment of all individuals and of eight to ten
individually marked specimens per treatment 56

Figure 2.4: Microprobe images of new grown calcite layer from high and low pCO treatment with 2
Mn-markings 57

Figure 2.5: Amount of shells with etched areas at inner shell surface 58

Figure 2.6: Pictures and SEM images of the inner surface (nacre) and the umbo region of shells from
high and low pCO treatment 61 2

I 2+ 2+Figure 2.7: Changes of Mg and Sr concentrations in the body fluids of Mytilus edulis and the
2+ambient water relative to changes in Ca 63

Figure 2.8: Sr/Ca ratios of body fluids and water from this study and from shell of relative to
Mg/Ca 65

10 11Figure 3.1: Spectra around B and B in low and high resolution mode 83

Figure 3.2: One analytical run of 7 ablation periods on NIST610 bracketed by 8 ablation periods on
Ce95-1 as bracketing standard 84

11Figure 3.3:  B in corals cultured under different pH conditions 88

Figure 4.1: Position of laser ablation lines on M. edulis shell 100

Figure 4.2: Acid-base status of hemolymph and extrapallial fluid and of the seawater at sampling day
compared to treatment pCO at day of sampling 104 2

Figure 4.3: Elemental ratios vs. calculated internal pH values 107

Figure 4.4: Distribution coefficient of EPF and water elemental ratios compared to shell mass growth
of bivalves during experimental time 109

11Figure 4.5:  B measured in M. edulis shells and precipitated under different pCO conditions in 2
relation to data of other carbonates 111















II List of Tables
Table 1.1: Instrument parameters 36

Table 1.2: Means and variances of shell parts grown in nature 37

Table 2.1: Water conditions during experimental trials 52

Table 2.2: Weekly measurements of calcification rates in nmol CaCO /g FW/h 54 3

Table 2.3: Mean values of increment growth of ten individually marked mussels per treatment at start
of the experiment and four different time points until the end of the experiment 58

Table 2.4: Calcification rates before CO gassing and mean calcification rates during the whole 2
experiment, increment of growth from beginning of the experiment to the end and amount of shells
with etched areas of the inner surface 60

Table 2.5: Mean elemental ratios of all matrices per aquarium 66

Table 2.S1: Alkalinity measurements of the different treatments with date and incubation time 74

Table 2.S2: Length growth of individually marked specimens at five dates during experiment 75

Table 2.S3: Element concentrations of water, HL and EPF (experiment 1) 76

Table 2.S4: Element concentrations of water and EPF (experiment 2) 77

Table 3.1: Instrumental parameters 82

11Table 3.2:  B results of stand