Predicting future climate- and catchment-driven risks to the ‘land-water-shellfish continuum’: towards improved decision-support for Scotland’s shellfish waters

Supervised by Dr David Oliver (University of Stirling), Prof Richard Quilliam (University of Stirling) and Dr Sim Reaney (Durham University).

This PhD is in collaboration with the Scottish Environment Protection Agency, who will provide additional support as a CASE partner.

The Scottish shellfish food production industry currently has over 320 active aquaculture sites, is estimated to be worth approximately £9.5m at first sale value and plays a key role in supporting livelihoods in some of Scotland’s more remote rural communities. However, climate change is a concern to the Scottish shellfish farming industry because of the coupling of a highly hydrologically-connected landscape with increased risk of rainfall-driven contaminated runoff. In general, climate projections suggest increased risk of extreme rainfall events in Scotland and downstream consequences of reduced microbial water quality on shellfish production areas (SPAs) and shellfish water protected areas (SWPAs) can threaten the safety and quality of shellfish (primarily mussels and pacific oysters) intended for human consumption. While the severity and scale of future consequences of a changing climate on food safety remain unclear, qualitative evidence suggests that the potential impacts of changing weather patterns and climatic systems on aquatic environments used for food production are complex and varied. These can range from both the immediate effects of pollution from extreme events through to more subtle shifts in the nature of catchment hydrology.

Recently, we have developed a novel multi-scale modelling approach for assessing E. coli loading to catchment landscapes (ViPER), which is linked to a hydrological risk mapping tool, now known as SCIMAP-FIO, to enable the identification of critical source areas and ‘at-risk’ tributaries in catchments in terms of high E. coli loading. Resources available to food and environmental regulators are limited, hence models and tools capable of predicting the distribution of pollution risk across large landscape scales offer a means of prioritising effort and targeting scarce resource more efficiently and effectively.

Research objectives: The overarching aim of this studentship is to provide critical data on the impact of climate and land-use change on microbial pollution of S(W)PAs both now and into the future, thus delivering quantitative evidence to help safeguard Scotland’s economically and socially important shellfish industry. The student will forecast future scenarios of risk to Scotland’s shellfish harvesting industry as driven by projected climate change trends, e.g. changing rainfall patterns and intensity, and future shifts in rural and urban land use. Specifically, the research objectives are to:

1. Use the ViPER/SCIMAP-FIO models to generate spatially-distributed and temporally-variable catchment-scale risk outputs for SPAs in Scotland;
2. Identify a subset of three test catchments linked to vulnerable S(W)PAs and undertake a programme of water quality sampling to quantify model fit to observed water quality data through contrasting seasons;
3. Investigate associations between E. coli levels in shellfish at S(W)PAs, modelled outputs of ViPER/SCIMAP-FIO surface water quality in drainage networks and climatic & ‘within-catchment’ environmental datasets;
4. Predict how patterns of risk to S(W)PAs vary in response to different climate and land-use change scenarios;
5. Model catchment ‘what-if’ management and mitigation scenarios to quantify their likely microbial pollution risk-reduction to S(W)PAs from future climate and land-use change.

The studentship will therefore use a combined field and modelling-based approach to ultimately predict how microbial risk can be reduced via a range of management approaches that respond to likely environmental and climate change. Full details of the methods and approach can be found here: https://www.iapetus2.ac.uk/studentships/predicting-future-climate-and-catchment-driven-risks-to-the-land-water-shellfish-continuum-towards-improved-decision-support-for-scotlands-shellfish-waters/. As the PhD develops you will also liaise with an external collaborator, Dr Phil Bartie (Computing Science, Heriot-Watt University), to develop novel geospatial skills to further complement the studentship.