Interaction between intraspecific genetic diversity and environmental stress in early life-stage macroalgaeAl-Janabi, B., Kruse, I., Wahl, M. Helmholtz Center for Oceean Research, Kiel, Germany

Interaction between intraspecific genetic diversity and environmental stress in early life-stage macroalgae

Al-Janabi, B., Kruse, I., Wahl, M.

Helmholtz Center for Oceean Research, Kiel, Germany

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

500 µM

200 µM 200 µM ©B. Al-Janabi

Session: 067 CLIMATE CHANGE IN THE BALTIC SEA

Genetic diversity

Atlantic > Baltic Sea

Diversity Diversity

Genetic diversity

Atlantic > Baltic Sea

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.

Genetic diversity level exposed to climate change

Highly mature adult Fucus were collected.

Release of gametes was induced.

Settling of germlings on limestones cubes: edge length 2 cm

Settlement of germlings

© K. Maczassek

Diversity level 2

4 4

Pool

Diversity level 1

Cohort 1

Settlement of germlings

© K. Maczassek

Diversity level 2 Diversity level 1

Cohort 2

2 2

Diversity level 3

4 4

Highly mature adult Fucus were collected.

Release of gametes was induced.

Settling of germlings on limestones cubes: edge length 2 cm

Three diversity levels of Fucus germlings

versus

1 2 3 4 5 6 7 8

Diversity level 1 offspring of 1 parental pair each

Diversity level 2 offspring of 2 parental pairs each

Diversity level 3 offspring of 3 parental pairs

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

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

versus

Kiel Benthocosms – Climate change simulation

Bioacid 2 project: Benthic consortium

2013: A seasonal comparison 4 treatment levels

High Temperature + pCO

High temperature

High pCO

Ambient

n = 3

Temperature: + 5 °C

pCO

: + 600 µatm

0 20 40 60 80 100

Spring13 Summer Late summer Autumn Winter Spring14

Survival %

T+CO2+

T+ CO2- T- CO2+

T- CO2-

Temp * Temp * Temp *

Germlings’ survival under climate change

Seasonal variation between spring, summer and late summer (p-value < 0.0001)

Warming causes lower survival from in summer(p-value < 0.05) and also in winter (p-value < 0.05)

Cohorte 2 Cohorte 1

Means +SD n=3

Germlings’ growth under climate change

Means +SD n=3

-10 10 30 50 70 90

Spring Summer Late summer Autumn Winter Spring14

Growth (% per day)

T+CO2+

T+CO2- T-CO2+

T-CO2-

Temp * Temp Temp *

Warming increases growth in spring and in summer (p-value < 0.05)

High pCO₂ increases growth in late summer.

Seasonal variationdetermines growth in autumn, winter and spring (p-value < 0.05) Season *

Cohorte 2 Cohorte 1

Germlings’ growth under climate change

-10 10 30 50 70 90

Spring Summer Late summer Autumn Winter Spring14

Growth (% per day)

T+CO2+

T+CO2- T-CO2+

T-CO2-

Temp * Temp Temp * Season *

Cohorte 2 Cohorte 1

pCO₂ effect on growth

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

Area (mm2) 380

1120 2400

µatm µatm µatm

Means +SD n=3

Diversity level effect on survival

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

Diversity level 1 Diversity level 2 Diversity level 3

Means +SD n=3

Survival in the high diversity level > survival low diversity level (p-value < 0.05) at high temperatures

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

Sibling groups’ co-tolerance to multiple stressors

Resistance towards multiple stressors depends:

Relationship co-tolerance

Stress induced community tolerance

antagonistic interaction between the two abiotic factors

Sibling groups were ranked for tolerance to temperature and pCO

Tolerances to temperature and pCO

were correlated

Vinebrook et al. (2004)

Sibling groups’ co-tolerance to multiple stressors

Spring 2013

R² = 0,907

0 1 2 3 4 5 6 7 8 9

0 1 2 3 4 5 6 7 8 9

Rank CO2

Rank T

Survival

R² = 0,8622

0 1 2 3 4 5 6 7 8 9

0 1 2 3 4 5 6 7 8 9

Rank CO2

Rank T

Growth

Positive sibling group co-tolerance for sibling groups with regard on survival and growth Stress-induced community tolerance

Antagonistic interaction between the factors temperature and pCO₂

Antagonistic interaction: Temperature and pCO

-1,5 -1 -0,5 0 0,5 1

1 2 3 4 5 6 7 8

Log (Survivalratio)

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

log effect ratio = log Survival (T+) Survival (T-) Log effect ratio: Survival in Spring

Survival differences after eutrophication

0 20 40 60 80 100 120

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

Survival%

1 2 3

C over

Means +SD n=3

Diversity level

low medium high

Nutrients Survival during heat wave (p-value < 0,05)

© I. Lastumäki

Conclusions

• Warming has stronger effects on germlings’ performance than high pCO₂

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

• Seasonal variation determines climate change effects on growth and survival

• Higher diversity level show higher survival than low diversity level

• The positive co-tolerance relationship to warming and acidification lead to an antagonistic interaction

• Eutrophication mitigates mortality during a heat wave in summer

© I. Lastumäki

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

500 µM

200 µM 200 µM ©B. Al-Janabi

Muchas gracias por su attencion!