Tolerance to climate change of early life-stage Fucus vesiculosus

Tolerance to climate change of early life-stage

Fucus vesiculosus varies among sibling groups

Balsam Al-Janabi ¹, Inken Kruse ¹, Angelika Graiff ², Ulf Karsten ² and Martin Wahl ¹

1 GEOMAR, Helmholtz Center for Ocean Research, Kiel, Germany

2 University of Rostock, Applied Ecology and Phycology, Rostock, Germany

© I. Lastumäki © Inken Kruse © B. Al-Janabi © K. Maczassek

500 µM

200 µM 200 µM © B. Al-Janabi

1

Genetic diversity of Fucus vesiculosus

Diversity

Diversity

Confers potential for adaptation through selection Allows for resilience and ecosystem services

Hypothesis: Populations of high genetic diversity perform better on environmental stress.

2

Genotyping of 42 adult Fucus vesiculosus

-> their physiological responses at the Benthocosms experiment (T x CO2) were analysed Angelika Graiff

9 microsatellite markers were used to describe the genetic diversity:

Parameters:

H_O Observed Heterozygosity H_E Expected Heterozygosity F_IS Inbreeding factor

Fucus vesiculosus – Bülk Population

Genetic diversity of Fucus vesiculosus

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Microsatellite analysis of 42 adult F. vesiculosus

Locus N_A Size range (bp) H_O H_E F_IS

L85 8 112 - 126 0,7105 0,6274 - 0,135

L94 5 151 - 184 0,9000 0,6038 -0,500

Fsp1 11 122 - 160 0,8158 0,8242 0,010

Fsp2 17 115 - 195 0,5000 0,9069 0,452

F9 10 184 - 212 0,6579 0,8182 0,198

F19 10 162 - 192 0,5714 0,6779 0,159

F34 8 186 - 220 0,9750 0,6655 -0,474

F36 3 216 - 224 0,9231 0,5891 -0,579

F60 3 188 - 194 0,3000 0,4165 0,282

Total x = 8.33 ^{0,7060 0,6810} Estimation multilocus: - 0,0370

Settlement of germlings

© K. Maczassek

Diversity level 2

2x

Collection of fertile adult Fucus vesiculosus Induction of gamete release

Settling of germlings on limestones cubes: edge length 2 cm.

Diversity level 3

4x

Diversity level 1

1x

5

versus

1 2 3 4 5 6 7 8

offspring of 1 parental pair each

offspring of 2 parental pairs each

offspring of 4 parental pairs each

1, 2 3, 4 5, 6 7, 8

5, 6, 7 , 8 1, 2, 3, 4

versus

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Diversity level

Low

Medium

High

Three diversity levels of Fucus vesiculosus gemlings

Climate change scenario: Kiel Benthocosms

Investigation of species interactions and community structure under climate change Upscaling of: Multiple factors, Multi-species communities, Multi-seasonal approach

Closing the gap between laboratory and field experiments Flow-through system allows a near natural scenario

Wahl et al. 2015 Limnology and Oceanography: Methods 7

Warming and acidification: Kiel Benthocosms

Temperature: + 5 °C pCO

: 1100 µatm

8

4 treatment levels

High Temperature + pCO

High Temperature

High pCO

Ambient (Fjord conditions) n = 3

Seasonal variation - 2013

Seasonal differences between spring and summer (p-value < 0.05)

Season *

0 20 40 60 80 100

Spring13 Summer Autumn Winter Spring14

Survival % ^T+CO2+_{T+ CO2-}

T- CO2+

T- CO2-

Warming decreases survival in summer and also in winter (p-value < 0.05)

Warming and acidification in a seasonal environment

Means +SD n=3

Temp * Temp *

9

Seasonal differences between spring and summer (p-value < 0.05)

Season *

0 20 40 60 80 100

Spring13 Summer Autumn Winter Spring14

Survival % ^T+CO2+

T+ CO2- T- CO2+

T- CO2-

Warming decreases survival in summer and also in winter (p-value < 0.05)

Acidification effect on growth – Laboratory approach

Means +SD n=3

Temp * Temp *

10

0 0,2 0,4 0,6 0,8 1

Area (mm2)

380 1120 2400

pCO₂ effect on growth

High pCO₂ levels increase growth of Fucus germlings (p-value < 0.05) = fertilisation effect

Means +SD n=3

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Siblings vary in tolerance to warming and acidification

-2 -1 0 1 2

1 2 3 4 5 6 7 8

Survival %

log effect ratio (SD) (relative to “ambient”)

T+/ T- CO₂ +/ CO₂ - Future/ Present Temp

CO₂ Temp

Temp CO₂

Temp CO₂

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Warming, acidification and nutrient enrichment

Temperature: + 5 °C

pCO

: 1100 µatm

[Temperature + pCO

] x ^Nutrients

[NO

NO

PO

]

12

Nutrient enrichment mitigates heat wave stress

0 0,5 1 1,5 2 2,5 3 3,5

T-CO2-N- T-CO2-N+ T+CO2+ N- T+CO2+ N+

Growth % d-1

0 20 40 60 80 100

T-CO2-N- T-CO2-N+ T+CO2+ N- T+CO2+ N+

Survival %

TempCO₂- N- TempCO₂- N+ TempCO₂+ N- TempCO₂+ N+

***

***

Warming during a heat wave decreased survival and growth significantly (p < 0.0001)

Nutrient enrichment attenuates the high mortality and growth reduction (p < 0.0001)

Warming+Acidification interacts with the factor nutrients (p <

0.0001)

+N

+N

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+T

+T

Local Upwelling event

[Temperature + pCO

] x ^Nutrients

[NO₂ NO₃ PO₄]

+ [Temperature + pCO₂] + Nutrients + [Temperature + pCO₂] - Nutrients - [Temperature + pCO₂] + Nutrients

- [Temperature + pCO₂] - Nutrients

3 days Upwelling

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Sensitivity to hypoxia is enhanced by previous warming

Mortality of F. vesiculosus germlings is strongly increased under hypoxia in all groups of pre-treatments

Previous exposure to warming and acidification decreased the tolerance to

hypoxia stress (p < 0.001) ¹⁵

0 20 40 60 80 100

TCO2- N- TCO2- N+ TCO2+ N- TCO2+ N+

Mortality %

Pre-treatment TempCO₂- N- TempCO₂- N+ TempCO₂+ N- TempCO₂+ N+

3 days Hypoxia

Genotypic correlations determine the direction of selection

Vinebrook et al. (2004)

Populations resistance to multiple factors depend on trade correlation

Analysis of sibling groups sensitivity towards multiple stressors was performed Sibling groups sensitivity to stressor A and stressor B may correlate

genotypic correlations

Sibling groups were ranked according to the different sensitivities:

Warming Acidification

Warming + acidification

Hypoxia

Siblings correlations of sensitivities to warming and OA

0 1 2 3 4 5 6 7 8

0 1 2 3 4 5 6 7 8

6 4

8

3 1

7 5

2

0 1 2 3 4 5 6 7

0 1 2 3 4 5 6 7

5

4

6

1

3

7

8

Survival

0 1 2 3 4 5 6 7 8

0 1 2 3 4 5 6 7 8

R = 0.929 P = 0.0022 6

4 8

1

3

7

5

Growth 2

Rank sensitivity to CO2

Rank sensitivity to temperature

Spring

R = 0.952 P = 0.0011

SpringSummer

R = 0.821 P = 0.0341

Growth

Sensitivity to warming and acidification is positively correlated (p < 0.05)

Direction of selection goes towards the more tolerant genotypes to warming and acidification

Positive correlation will accelerate selection processes towards these genotypes

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0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Sensitivity to TempCO 2

Sensitivity to Hypoxia

6 10

4

9

16 5

8

13 11

14 1

3 2

15 12

7

R = - 0.8088 P = 0.0002

Correlations of sensitivities to OAW and hypoxia

Sensitivity towards warming+acidification and hypoxia is negatively correlated

(p < 0.001)

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Genotypes adapted to warming and

acidification are most sensitive to hypoxia

Conclusions

• Warming enhances growth in summer, but reduces survival in late summer

• Seasonal variation determines climate change effects on growth and survival

• Sibling groups vary in their response to warming and acidification

-> potential for adaptation

• Heat wave stress is mitigated under nutrient enrichment but enhances the sensitivity to hypoxia

• Positive correlation of sensitivities towards warming and acidification determines the direction of selection

• Populations adapted to warming and acidification are most sensitive to hypoxic upwelling

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Acknowledgments

Martin Wahl Inken Kruse

Angelika Graiff Ulf Karsten Björn Buchholz

Federal Ministry of Education and Research 20

baljanabi@geomar.de

Acknowledgments

Prof. Dr. Martin Wahl Dr. Inken Kruse

Angelika Graiff

Prof. Dr. Ulf Karsten

Thank you for your attention!

© I. Lastumäki © Inken Kruse © B. Al-Janabi © K. Maczassek

500 µM

200 µM 200 µM © B. Al-Janabi

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Higher diversity level survive better under warming

0 20 40 60 80 100

T+ CO2+ T+ CO2- T- CO2-

Survival %

Autumn

0 20 40 60 80 100

T+ CO2+ T+ CO2- T- CO2-

Survival %

Winter

DL 1 DL 2 DL 3

Means +SD n=3

Survival high diversity level

>

Increased survival for a group of many families indicated facilitation processes among different genotypes

Diversity level low

medium high

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Table 1 Nutrient concentrations in the present (mean of the last 7 years

according to the respective summer months) and future nutrient conditions as doubled amounts of the present nutrient concentrations for PO₄, NO₂, NO₃ in µmol L^-1.

July

August

September

Present Future Present Future Present Future

PO₄ 0.46 0.93 0.59 1.19 1.06 2.11

NO₂ 0.53 1.05 0.77 1.54 1.27 2.54

NO₃ 0.18 0.36 0.20 0.40 0.22 0.44

Nutrient treatment

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