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Effects of global warming and ocean acidification on benthic communities in the German Wadden Sea - examined with mesocosm experiments - BIOACID Annual Meeting, September 2014, Kiel Andreas Pansch 1 , Harald Asmus 1 , Ragnhild Asmus 1 , Birte Mensch 2 , Vera Winde 3 , Martin Wahl 4 1 Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Wadden Sea Station Sylt 2 Christian-Albrechts-University Kiel 3 IOW, Leibnitz Institute for Baltic Research Warnemünde 4 GEOMAR, Helmholz Centre for Ocean Research Kiel

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Page 1: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Effects of global warming and ocean

acidification on benthic communities

in the German Wadden Sea - examined with mesocosm experiments -

BIOACID Annual Meeting, September 2014, Kiel

Andreas Pansch1, Harald Asmus1, Ragnhild Asmus1, Birte Mensch2, Vera Winde3, Martin Wahl4

1Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Wadden Sea Station Sylt 2Christian-Albrechts-University Kiel 3IOW, Leibnitz Institute for Baltic Research Warnemünde 4GEOMAR, Helmholz Centre for Ocean Research Kiel

Page 2: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Why mesocosm studies ?

Close the gap between small scale lab experiments and field

studies

Experiments with communities instead of single species

under controlled conditions

Investigation of species interactions and community structure

under climate change

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AWI Wadden Sea Station 03.06.14 17:06Google Maps

Seite 1 von 1https:/ / www.google.de/ maps/ @54.1500743,8.3292339,8z

Kartendaten © 2014 GeoBasis-DE/BKG (©2009), Google 20 km

www.google.de/maps

Page 4: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Mesocosms facilities - Sylt

Constructed by 4H-Jena Engineering

Finished in August 2013

12 mesocosms 12 independent experimental units

Non filtered seawater from the Wadden Sea Station

Connected with the CO2-gas mixing facility of the institute

Made for climate change experiments

at the ecosystem level

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Single mesocosm

170 cm in diameter x 80 cm height

1800 l volume

Insulated wall construction

Translucent lid

Temperature regulation

Multiparameter measurement system

Flow through

Tide simulation

Software

Page 6: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Tide simulation

IMG_0946.JPG

Page 7: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Tide simulation

low tide

Page 8: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Tide simulation

high tide

Page 9: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Temperature regulation

Aqua medic®

Titanium heater

3 x 500 W

Aqua medic®

Titan 2000 cooler

550 W

Software:

yearly

max/min

daily max/min

adjusted by

measured

temperatures

in the field

Page 10: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Temperature regulation

+ 5 °C

Page 11: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

CO2-gas mixing facility

Seawater in each

mesocosm is directly

aerated with pre-

mixed gas

Page 12: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Seawater acidification

380 ppm

1000 ppm

Page 13: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Multi-parameter measurements

One system for two mesocosms:

Hydrolab DS5X

Parameters measured at the moment

• temperature

• pH

• oxygen (Clark cell)

• conductivity

Possible adjustments in the future

• chlorophyll

• turbidity

• Ammonium etc.

Page 14: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Software

Page 15: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

First experiments

autumn 2013 + spring 2014

Macro algal community

(Fucus vesiculosus)

3 month

CO2 x temperature

4 treatments (3 replicates)

Ambient

Warm Ambient + 5 °C

Acid 1000 ppm

Warm + Acid + 5 °C, 1000 ppm

Page 16: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Fucus vesiculosus

Ambient Warm Acid Warm+Acid

28

03

00

32

03

40

Incre

ase

in

Bio

ma

ss (

%)

Ambient Warm Acid Warm+Acid

10

61

08

11

01

12

11

4

Incre

ase

in

Bio

ma

ss (

%)

Autumn 2013 Spring 2014

• Warming inhibited Fucus growth

• Elevated pCO2 increased Biomass

• Stress combination acted antagonistically

p= 0.007 ** p= 0.092

Page 17: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Gammarus sp.

• Warming increased the number of Gammarus offspring

Ambient Warm Acid Warm+Acid

50

01

00

01

50

02

00

02

50

03

00

0

# o

f G

am

ma

rus p

er

Be

nth

oco

sm

Abundance

p= 0.073

Ambient Warm Acid Warm+Acid

0.0

04

0.0

06

0.0

08

0.0

10

0.0

12

Ga

mm

aru

s (

mg

Dry

we

igh

t/In

div

idu

al)

Dry weight per Individual

p= 0.288

Spring 2014

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Gammarus sp.

• Warming increased the number of Gammarus offspring

Ambient Warm Acid Warm+Acid

46

81

01

21

4

Ga

mm

aru

s (

mg

Dry

we

igh

t p

er

Be

nth

oco

sm

)

Dry weight per Benthocosm

p= 0.424

Spring 2014

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Corophium sp.

• Warming and acidification as well the combination of both

increased the abundance of Corophium sp.

Ambient Warm Acid Warm+Acid

10

02

00

30

04

00

# o

f C

oro

ph

ium

pe

r B

en

tho

co

sm

Ambient Warm Acid Warm+Acid0

.00

04

0.0

00

60

.00

08

0.0

01

00

.00

12

0.0

01

40

.00

16

Co

rop

hiu

m (

mg

Dry

we

igh

t/In

div

idu

al

Abundance Dry weight per Individual

p= 0.624 p= 0.650

Spring 2014

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Hydrobia ulvae

• Warming and acidification as well the combination of both

increased the abundance and growth of Hydrobia ulvae

Ambient Warm Acid Warm+Acid

20

04

00

60

08

00

# o

f H

yd

rob

ia p

er

Be

nth

oco

sm

Ambient Warm Acid Warm+Acid0

.00

20

.00

30

.00

40

.00

5

Hyd

rob

ia (

mg

Dry

we

igh

t/In

div

idu

al

Hyd

rob

ia (

mg D

ryw

eig

ht/In

div

idu

al)

Abundance Dry weight per Individual

p= 0.365 p= 0.226

Spring 2014

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Juvenile Littorina littorea

• Warming and acidification as well the combination of both

increased the abundance of L. littorea offspring

• Warming increased the growth of juvenile L. littorea

Ambient Warm Acid Warm+Acid

50

10

01

50

20

02

50

30

0

# o

f ju

ve

nile

Litto

rin

a litto

rea

pe

r B

en

tho

co

sm

Ambient Warm Acid Warm+Acid0

.00

50

.01

00

.01

50

.02

0

juve

nile

Litto

rin

a litto

rea

(m

g D

ryw

eig

ht/In

div

idu

al)Abundance Dry weight per Individual

p= 0.647 p= 0.012 *

Spring 2014

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adult Littorina littorea

• Warming reduced the biomass of adult L. littorea

Ambient Warm Acid Warm+Acid

1.8

1.9

2.0

2.1

2.2

2.3

Litto

rin

a litto

rea

(m

g/In

d)

Abundance

• No change in abundance

Dry weight per Individual

p= 0.370

Spring 2014

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Littorina mariae

• Warming and acidification as well the combination of both

increased the abundance of L. mariae

• Growth increased under the combination of warning and high pCO2

Ambient Warm Acid Warm+Acid

50

01

00

01

50

02

00

0

# o

f L

itto

rin

a m

aria

e p

er

Be

nth

oco

sm

Ambient Warm Acid Warm+Acid0

.00

50

.01

00

.01

50

.02

00

.02

50

.03

0

Litto

rin

a m

aria

e (

mg

Dry

we

igh

t/In

div

idu

al)

Abundance Dry weight per Individual

p= 0.331 p= 0.617

Spring 2014

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Mytilus edulis

• Warming decreased the abundance of M. edulis offspring and

growth of M. edulis adults

• Elevated CO2 increased the abundance of offspring

Ambient Warm Acid Warm+Acid

30

40

50

60

70

80

90

# o

f M

ytilu

s o

ffsp

rin

g

Ambient Warm Acid Warm+Acid

-10

12

34

56

Incre

ase

in

sh

ell

len

gth

(%

)

Abundance Shell length

p= 0.575 p= 0.002 **

Spring 2014

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Crassostrea gigas

• Elevated CO2 decreased growth of C. gigas

• The combination of warming and elevated CO2

led to control growth

Ambient Warm Acid Warm+Acid

51

01

52

0

Incre

ase

in

sh

ell

len

gth

(%

)

Abundance Shell length

• No settled oysters were found p= 0.333

Spring 2014

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Summary

Warm Acid Warm+Acid

Fucus vesiculosus

Gammarus sp.

Corophium sp.

Hydrobia ulvae

Juv. L. littorea

Adult L. littorea

Littorina mariae

Mytilus edulis

Crassostrea gigas

Page 27: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Conclusions

No obvious negative effects at elevated pCO2

Warming impacted Fucus and Mytilus negatively

Combination of warming and acidification acted antagonistically

Importance of multiple stressor experiments

Important to differentiate between direct and indirect effects

First results show higher impact of acidification on Wadden Sea

community than on Baltic Sea communities

Although single species effects were shown widely in the

literature, two of the main predicted future threats, warming

and acidification, do not negatively impact benthic

Wadden Sea assemblages

Page 28: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Future plans

Summer 2014 (still running)

Fucus vesiculosus community (CO2 x temperature) x eutrophication

Test with Ecological Network Analysis

Experiments on Seagrass communities

Test of more stressors, stress combinations, species, life stages and communities

• fish larvae, small fish

• turbidity, deoxygenation, hyposalinity, sedimentation, micro plastics

Page 29: Effects of global warming and ocean acidification on ... · IMG_0946.JPG . Tide simulation low tide . Tide simulation high tide . Temperature regulation Aqua medic

Thanks for your

attention