SD4: Improved understanding of population, community and ecosystem impacts of ocean acidification for commercially important species
Lead Research Organisation:
University of Strathclyde
Department Name: Mathematics and Statistics
Abstract
Predicting the impacts of ocean acidification (OA) upon fisheries is a rapidly evolving sphere of interest. This project, conducted between the Centre of Sustainable Aquaculture Research (Swansea), Exeter and Strathclyde Universities, and Plymouth Marine Laboratory, will address these challenges using a holistic multi-disciplinary approach. We will examine the physiological and life history responses of commercially important examples of bivalves, crustacea and finfish, using the large (750 m2 floor, 150 m3 water) state-of-the-art Centre for Sustainable Aquaculture Research at Swansea in which these organisms, together with their live food items, can be grown under the same conditions. We will compare the physiology and growth of the selected organisms at different water acidity and temperatures (increased acidity being associated with elevated CO2 and global warming). The output from these experiments will be scaled-up to identify effects at population and community levels. The consequences of these changes for the fishing industry will then be explored. OA, however, will not only affect commercially important species, and so the wider impacts for society of changes in marine ecosystems will also be examined. OA is expected to affect reproduction and early life stages in particular; our research will focus on egg fertilization and growth over the first 2-4 months. These stages can be acid-critical (e.g. sperm swimming is sensitive to acid levels) and are the most susceptible to the external environment due to their high surface-area: volume ratio and poor ability to compensate for changes in internal acidity. Early formation of shell and skeletal structures are also vulnerable to acid changes. OA will also provide direct and indirect effects through changes to food organisms. While it is not possible to change feed species composition, we will grow phytoplankton, zooplankton and other target animals to consider food chain impacts at different acidity levels and temperatures during their most sensitive period. This will enable us to consider the potentially synergistic effects of changes to food quantity and quality, the efficiency of food conversion into growth and energy, and the support of the food chain. Continuing these studies into juvenile stages will provide data for the impact of OA upon the most sensitive stages of cell growth. The results obtained during the studies of early life stages will be complemented by more detailed studies to identify the biological mechanisms that result in an organism's vulnerability to acidity and temperature change. Data from experiments will be used to develop models of organism growth which will provide a sound base for the future development of our understanding of OA upon other species. Supported with data collected from other OA projects, these models will then be developed to link with models that can explore the social and economic consequences to the fishing industry resulting from changes in fish populations. Existing models for such estimates are in their infancy but this project will integrate new developments that relate fisheries production to whole ecosystem ecology to improve upon classic, but simplistic, fisheries models. This is especially important when considering the impacts of global climate change and OA because of the varied interactions between organisms and their environment. Using the findings generated by this study and those arising from other OA projects, the wider impacts of OA on marine ecosystems will be explored. These will be used to examine how the benefits we obtain from the marine environment change (e.g. the availability of clean water for aquaculture and recreational activities, health benefits, and the regulation of gases and climate) and how the value of these benefits change. What these changes mean for industry and society will be explored.
People |
ORCID iD |
| Douglas Speirs (Principal Investigator) |
Publications
Campbell A
(2016)
Ocean acidification changes the male fitness landscape
in Scientific Reports
Campbell AL
(2014)
Ocean acidification increases copper toxicity to the early life history stages of the polychaete Arenicola marina in artificial seawater.
in Environmental science & technology
Heath MR
(2014)
Cascading ecological effects of eliminating fishery discards.
in Nature communications
Lewis C
(2016)
Ocean acidification increases copper toxicity differentially in two key marine invertebrates with distinct acid-base responses.
in Scientific reports
Liu Y
(2016)
Investigation of the effects of platform motion on the aerodynamics of a floating offshore wind turbine
in Journal of Hydrodynamics
Mangan S
(2019)
Acid-base physiology over tidal periods in the mussel Mytilus edulis: size and temperature are more influential than seawater pH.
in Proceedings. Biological sciences
Mangan S
(2017)
Fluctuating seawater pH/pCO2 regimes are more energetically expensive than static pH/pCO2 levels in the mussel Mytilus edulis.
in Proceedings. Biological sciences
| Description | The results indicate the primacy of fishing as the most important process affecting total fish biomass, together with varying responses to environmental factors which may be relevant in the context of climate change. The non-linear responses and parameter interactions identified by the analysis also highlight the necessity to use global rather than local methods for the sensitivity analysis of ecosystem models. The results indicate that ocean acidification may potentially induce cascading effects throughout marine ecosystems even when the direct effects are small. In particular our results indicate the efficiency with which food is converted to new consumer biomass - something which is known to be affected by acidification through changes in gut chemistry - has the biggest effect in the ecosystem model. We found that demersal fish (fish such as cod and haddock) are most sensitive to direct and indirect impacts. Moreover, indirect impacts can be simultaneously positive and negative. In fact changes of as little as 2% in functional group mortality can be magnified to 10% drop in landings. |
| Exploitation Route | The scaling of effects of direct impacts of environmental stressors such as ocean acidification remains as major challenge. Our results suggest that more experimental research is needed in order to quantify aggregated responses at the level of functional groups rather than individual species. We have focused on acidification, but further work is required on multiple stressors. |
| Sectors | Agriculture Food and Drink Environment |
| Title | Data from: Acid-base physiology over tidal periods in the mussel Mytilus edulis: size and temperature are more influential than seawater pH |
| Description | Ocean acidification (OA) studies to date have typically used stable open-ocean pH and CO2 values to predict the physiological responses of intertidal species to future climate scenarios, with few studies accounting for natural fluctuations of abiotic conditions or the alternating periods of emersion and immersion routinely experienced during tidal cycles. Here, we determine seawater carbonate chemistry and the corresponding in situ haemolymph acid-base responses over real time for two populations of mussel (Mytilus edulis) during tidal cycles, demonstrating that intertidal mussels experience daily acidosis during emersion. Using these field data to parameterise experimental work we demonstrate that air temperature and mussel size strongly influence this acidosis, with larger mussels at higher temperatures experiencing greater acidosis. There was a small interactive effect of prior immersion in OA conditions (pHNBS 7.7/pCO2 930 µatm) such that the haemolymph pH measured at the start of emersion was lower in large mussels exposed to OA. Critically, the acidosis induced in mussels during emersion in situ was greater (?pH ~0.8 units) than that induced by experimental OA (?pH ~0.1 units). Understanding how environmental fluctuations influence physiology under current scenarios is critical to our ability to predict the responses of key marine biota to future environmental changes. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2019 |
| Provided To Others? | Yes |
| URL | https://datadryad.org/stash/dataset/doi:10.5061/dryad.k11r5b9 |
| Title | Data from: Fluctuating seawater pH/ p CO 2 regimes are more energetically expensive than static pH/ p CO 2 levels in the mussel Mytilus edulis |
| Description | Ocean acidification (OA) studies typically use stable open-ocean pH or CO2 values. However, species living within dynamic coastal environments can naturally experience wide fluctuations in abiotic factors, suggesting their responses to stable pH conditions may not be reflective of either present or near-future conditions. Here we investigate the physiological responses of the mussel Mytilus edulis to variable seawater pH conditions over short- (6 h) and medium-term (2 weeks) exposures under both current and near-future OA scenarios. Mussel haemolymph pH closely mirrored that of seawater pH over short-term changes of 1 pH unit with acidosis or recovery accordingly, highlighting a limited capacity for acid-base regulation. After 2 weeks, mussels under variable pH conditions had significantly higher metabolic rates, antioxidant enzyme activities and lipid peroxidation than those exposed to static pH under both current and near-future OA scenarios. Static near-future pH conditions induced significant acid-base disturbances and lipid peroxidation compared with the static present-day conditions but did not affect the metabolic rate. These results clearly demonstrate that living in naturally variable environments is energetically more expensive than living in static seawater conditions, which has consequences for how we extrapolate future OA responses in coastal species. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2017 |
| Provided To Others? | Yes |
| URL | https://datadryad.org/stash/dataset/doi:10.5061/dryad.3v8s5 |
| Title | Improved understanding of population, community and ecosystem impacts of ocean acidification. |
| Description | "The project aims to model effects of ocean acidification on commercial species of the North Sea. It is using existing computer models (StrathE2E) developed at the University of Strathclyde, to predict possible outcomes of acidification. The model is made available from Prof Mike Heath, Dept Maths and Statistics. Data is used in the model to represent external drivers. The data was collected during previous model formulation. It consists of time series datasets representing physical, chemical and biological characteristics of the boundaries of the North Sea together with data on fishery catches and discards. This data was reduced in size to incorporate within the model, thus allowing the ecosystem of the North Sea to be represented." |
| Type Of Material | Database/Collection of data |
| Provided To Others? | No |
| Impact | Not recorded |
| URL | https://pure.strath.ac.uk/portal/en/datasets/improved-understanding-of-population-community-and-ecos... |
| Title | Seawater carbonate chemistry and acid-base parameters, metabolic rate and health indicators of Mytilus edulis |
| Description | Ocean acidification (OA) studies typically use stable open-ocean pH or CO2 values. However, species living within dynamic coastal environments can naturally experience wide fluctuations in abiotic factors, suggesting their responses to stable pH conditions may not be reflective of either present or near-future conditions. Here we investigate the physiological responses of the mussel Mytilus edulis to variable seawater pH conditions over short- (6 h) and medium-term (2 weeks) exposures under both current and near-future OA scenarios. Mussel haemolymph pH closely mirrored that of seawater pH over short-term changes of 1 pH unit with acidosis or recovery accordingly, highlighting a limited capacity for acid-base regulation. After 2 weeks, mussels under variable pH conditions had significantly higher metabolic rates, antioxidant enzyme activities and lipid peroxidation than those exposed to static pH under both current and near-future OA scenarios. Static near-future pH conditions induced significant acid-base disturbances and lipid peroxidation compared with the static present-day conditions but did not affect the metabolic rate. These results clearly demonstrate that living in naturally variable environments is energetically more expensive than living in static seawater conditions, which has consequences for how we extrapolate future OA responses in coastal species. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2017 |
| Provided To Others? | Yes |
| URL | https://doi.pangaea.de/10.1594/PANGAEA.890223 |
| Title | Seawater carbonate chemistry and acid-base physiology over tidal periods in the mussel Mytilus edulis |
| Description | Ocean acidification (OA) studies to date have typically used stable open-ocean pH and CO2 values to predict the physiological responses of intertidal species to future climate scenarios, with few studies accounting for natural fluctuations of abiotic conditions or the alternating periods of emersion and immersion routinely experienced during tidal cycles. Here, we determine seawater carbonate chemistry and the corresponding in situ haemolymph acid-base responses over real time for two populations of mussel (Mytilus edulis) during tidal cycles, demonstrating that intertidal mussels experience daily acidosis during emersion. Using these field data to parameterize experimental work we demonstrate that air temperature and mussel size strongly influence this acidosis, with larger mussels at higher temperatures experiencing greater acidosis. There was a small interactive effect of prior immersion in OA conditions (pHNBS 7.7/pCO2 930 µatm) such that the haemolymph pH measured at the start of emersion was lower in large mussels exposed to OA. Critically, the acidosis induced in mussels during emersion in situ was greater (delta pH approximately 0.8 units) than that induced by experimental OA (?pH approximately 0.1 units). Understanding how environmental fluctuations influence physiology under current scenarios is critical to our ability to predict the responses of key marine biota to future environmental changes. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2019 |
| Provided To Others? | Yes |
| URL | https://doi.pangaea.de/10.1594/PANGAEA.922198 |
| Title | Supplementary meta-data from Acid-base physiology over tidal periods in the mussel Mytilus edulis: size and temperature are more influential than seawater pH |
| Description | data file of all data |
| Type Of Material | Database/Collection of data |
| Year Produced | 2019 |
| Provided To Others? | Yes |
| URL | https://rs.figshare.com/articles/Supplementary_meta-data_from_Acid_base_physiology_over_tidal_period... |
| Title | Supplementary meta-data from Acid-base physiology over tidal periods in the mussel Mytilus edulis: size and temperature are more influential than seawater pH |
| Description | data file of all data |
| Type Of Material | Database/Collection of data |
| Year Produced | 2019 |
| Provided To Others? | Yes |
| URL | https://rs.figshare.com/articles/Supplementary_meta-data_from_Acid_base_physiology_over_tidal_period... |
| Title | Tables3_24hourpHmonitoring.csv from Fluctuating seawater pH/pCO2 regimes are more energetically expensive than static pH/pCO2 levels in the mussel Mytilus edulis |
| Description | Seawater pH over 24 hours of exposure for the four treatments. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2017 |
| Provided To Others? | Yes |
| URL | https://rs.figshare.com/articles/dataset/Tables3_24hourpHmonitoring_csv_from_Fluctuating_seawater_pH... |
| Title | Tables3_24hourpHmonitoring.csv from Fluctuating seawater pH/pCO2 regimes are more energetically expensive than static pH/pCO2 levels in the mussel Mytilus edulis |
| Description | Seawater pH over 24 hours of exposure for the four treatments. |
| Type Of Material | Database/Collection of data |
| Year Produced | 2017 |
| Provided To Others? | Yes |
| URL | https://rs.figshare.com/articles/dataset/Tables3_24hourpHmonitoring_csv_from_Fluctuating_seawater_pH... |
| Description | Joint research with Swansea University |
| Organisation | Swansea University |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | University of Strathclyde researchers worked on this project with researchers from Swansea University |
| Start Year | 2012 |
| Description | Joint research with University of Exeter |
| Organisation | University of Exeter |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | University of Strathclyde researchers worked on this project with researchers from University of Exeter |
| Start Year | 2012 |
| Description | Finale event for the UK Ocean Acidification research programme (UKOA) held jointly with the German programme Biological Impacts of Ocean Acidification (BIOACID) |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | A Finale Event for the UK Ocean Acidification research programme was held at the Royal Society, London on 4-5 July 2015 called "Ocean acidification: what's it all about?", and covering both UKOA and the German BIOACID programme. The meeting was public, and primarily for stakeholders and research users (policy, business, media, NGOs and scientists from other disciplines) who have not been directly involved in OA research to date; the emphasis was therefore be on non-technical overviews and cross-cutting topics, to highlight major UKOA outcomes. |
| Year(s) Of Engagement Activity | 2015 |
| URL | http://www.oceanacidification.org.uk/Latest_News/Royal_Society |