Transcript Widdicombe_EPOCA_Theme 2_Scientific_Highlight

European Project on Ocean Acidification (EPOCA)
Theme 2 – Scientific Highlight
“Linking individual responses to
impacts on ecosystems”
Dr Steve Widdicombe
10th-13th June 2008, La Maison du Séminaire, Nice (France)
Introduction
Examples of impact on marine
organisms.
Whole organism impacts and
trade-offs
Interactions between species
Impacts on communities and
ecosystem function
Predicting biodiversity
Research at PML – Impact Experiments
PML has developed a range of
experimental systems the can
provide large quantities of CO2
acidified seawater
Large systems successfully used
to look at impacts of large organisms
and sediment cores.
Small systems used for small
organisms and larvae.
CO2 gas
Regulator
Natural
seawater
Acidified
seawater
pH & temp
sensor
Water pump for
circulation
Control box
LAN / internet
connection
Findlay et al (in press Aquatic Biology)
Widdicombe & Needham (2007) Mar Ecol Prog Ser
Impact on Individuals
Physiological
Response to High CO2
Sea urchin
Crab
(Miles et al. 2007 Mar. Pollut. Bull. 54, 89-96)
(Spicer et al. 2007 Mar. Biol. 151, 1117-1125)
Impact on Animal Health
Impact on Animal Health – Immune Response
Seawater acidification reduced immune
response in mussels
(Bibby et al. 2008 Aquatic Biology 2, 67 - 74)
Seawater acidification also reduced
mussel general heath status (NRR assay)
(Beesley et al. in press Climate Change)
Normal
Abnormal
Whole Organism Impacts
Key Survival Processes
INPUT
MAINTENANCE
ORGANISM
OUTPUTS
GROWTH
Calcium content
FEEDING
METABOLISM
Arm regrowth
O2 uptake
REPRODUCTION
Egg size & condition
umol oxygen/day/g animal
± 95% CI
Whole Organism Physiology
140
120
100
80
60
40
20
0
8
7.7
7.3
6.8
Reduced pH caused a significant
30
25
20
15
10
5
0
increase in oxygen consumption
8
7.7
7.3
6.8
Length of arm regrown significantly
longer at lower pH
pH treatment
% calcium/ g of arm ± 95% CI
length mm ± 95% CI
pH
40
Reduced pH significantly increased the
calcium content in regrown arms
established
regrowth
35
30
25
20
Regrown arms had significantly higher
calcium content than existing arms
15
10
5
0
8
7.7
7.3
6.8
pH
Wood et al. (2008) Proceedings of the Royal Society B
The Biological Cost
control
7.7
7.3
6.8
control
7.7
Established arms
Regrowing arms
Wood et al. 2008. Proceedings of the Royal Society B
7.3
6.8
Behaviour and Interactions
HELP!
There are crabs in this
habitat, I must thicken
my shell
Phenotypic
plasticity
Chemical cue
Edible Periwinkle
Littorina littorea
Green Shore Crab
Carcinus maenas
In a future ocean where the availability of
bicarbonate ions are reduced, snails may
be less able to thicken their shells and
could therefore be more vulnerable to
predation.
Bibby et al. 2007. Biology Letters 3: 699-701.
Community Structure & Biodiversity
Communities made up of
species with a range of tolerance
to high CO2
Polychaetes – Crustaceans –
Molluscs – Echinoderms
Species diversity (√S)
Mud
2 weeks
Differences seen within and
between taxonomic groups
6
5
4
No relationship
3
Mud and sand communities
showed different tolerances
Prediction will come from
knowing the mechanisms that
underpin organism tolerance
20 weeks
7
2
1
Sand
5
6.0
4
5.5
3
5.0
2
4.5
1
4.0
0
Long term experiments needed
5.5
6.0
6.5
7.0
7.5
8.0
5.5
6.0
6.5
7.0
7.5
8.0
pH treatment
Widdicombe et al. Submitted. Mar. Ecol. Prog. Ser
Why do changes in communities matter?
Burrow builders
7.9
7.3
6.5
5.6
80
120
100
100
CONTROL
µmol m-² h-¹
60
40
20
0
7.9
7.3
-20
6.5
5.6
-40
80
80
60
40
50
100
150 200 250 300 350 400
(Widdicombe & Needham, 2007)
60
40
20
0
20
-20
0
0
0
Nitrate
μmol.m-2.h-1
120
7.6
Nitrate
100
Bulldozers
20
40
60
0
20
40
60
(Widdicombe et al., in prep)
Different types of animals with different
behaviours have different impacts on ecosystem
function.
Will functional diversity be maintained?
Impacts: Sediment Fluxes
Sand
2 weeks
NO2 = -1.573 + 0.278pH
NO2 = -2.862 + 0.5081pH
3.0
2.0
1.5
1.0
0.75
0.50
0.50
ns
0.25
0.25
0.5
0
-0.5
0.00
0.00
F = 15.81; p = 0.001
5.5
6.0
6.5
7.0
7.5
20 weeks
NO2 = -1.429 + 0.2496pH
0.75
2.5
Nitrite
Mud
2 weeks
20 weeks
F = 42.65; p = 0.000
F = 53.83; p = 0.000
5.5
8.0
6.0
6.5
7.0
7.5
5.5
8.0
6.0
6.5
7.0
7.5
8.0
NO3 = -41.73 + 7.496pH
NO3 = 108.5 + 19.00pH
30
Nitrate
60
20
40
10
20
ns
0
-10
F = 35.90; p = 0.000
Ammonium
-20
5.5
6.0
6.5
7.0
7.5
8.0
NH4 = 350.9 – 39.60pH
300
F = 5.13; p = 0.036
250
200
150
100
50
0
5.5
6.0
6.5
7.0
7.5
8.0
-20
60
50
40
30
20
10
0
-10
-20
F = 18.77; p = 0.000
5.5
6.0
6.5
7.0
7.5
8.0
NH4 = 104.5 – 13.17pH
NH4 = 351.1 – 42.73pH
F = 11.75; p = 0.003
NH4 = 85.15 – 9.453pH
160
40
120
30
80
20
40
10
0
5.5
SiO = -70.84 + 18.56pH
Silicate
ns
0
6.0
6.5
7.0
7.5
8.0
F = 30.72; p = 0.000
5.5
6.0
6.5
7.0
7.5
8.0
0
F = 18.72; p = 0.001
5.5
6.0
7.5
100
80
80
60
60
ns
40
40
20
ns
20
F = 7.41; p = 0.014
5.5
6.0
6.5
7.0
7.5
7.0
SiO = -61.94 + 16.31pH
100
0
6.5
8.0
F = 8.85; p = 0.008
0
5.5
Seawater pH
6.0
6.5
7.0
7.5
8.0
Seawater pH
8.0
What do we need to know to predict biodiversity response?
Species diversity
What are the mechanisms that make acidification detrimental to the survival of
individuals and the long term sustainability of populations?
How do these mechanisms vary between species?
How will acidification interact with other climate change stressors to set
biogeographical limits?
What will be the impact on biological control (predation, competition,
ecosystem engineers, keystone species)?
Will adaptation mitigate the effects of ocean acidification?
Taxonomic (or phylogenetic) diversity
Is an organism’s tolerance related to its phylogeny or its ecology?
Functional diversity
What is it that different organisms do for ecosystem function?
What is the relationship between biodiversity and ecosystem function anyway?
(Widdicombe & Spicer. In press. Predicting the impact of Ocean acidification on benthic biodiversity:
What can physiology tell us? Journal of Experimental Marine Biology and Ecology)
References
S Widdicombe & JI Spicer. In press. Predicting the impact of ocean acidification on
benthic biodiversity: What can physiology tell us? Journal of Experimental Marine Biology
and Ecology
HL Wood, JI Spicer & S Widdicombe. In press. Ocean Acidification may increase
calcification rates- but at a cost. Proceedings of the Royal Society B
A Beesley, DM Lowe, C Pascoe & S Widdicombe. In press. Impact of CO2 induced
seawater acidification on the health of Mytilus edulis. Climate Change
R Bibby, S Widdicombe, H Parry, JI Spicer & R Pipe. 2008. Impact of ocean acidification
on the immune response of the blue mussel Mytilus edulis. Aquatic Biology 2: 67-74.
R Bibby, P Cleall-Harding, S Rundle, S Widdicombe & J Spicer. 2007. Ocean acidification
disrupts induced defences in the intertidal gastropod Littorina littorea. Biology Letters 3:
699-701.
S Widdicombe & HR Needham. 2007. Impact of CO2 induced seawater acidification on
the burrowing activity of Nereis virens and sediment nutrient flux. Marine Ecology
Progress Series 341: 111-122.
JI Spicer, A Raffo & S Widdicombe, 2007. Influence of CO2-related seawater acidification
on extracellular acid-base balance in the velvet swimming crab Necora puber. Marine
Biology 151: 1117-1125.
H Miles, S Widdicombe, JI Spicer & J Hall-Spencer, 2007. Effects of anthropogenic
seawater acidification on acid-based balance in the sea urchin Psammechinus miliaris.
Marine Pollution Bulletin 54:89-96.
S Widdicombe, et al., in prep. The response of Brissopsis lyrifera and Echinocardium
cordatum to CO2 induced sweater acidification.