Evaluating the potential of multi-trophic aquaculture to improve nutrition and ecosystem sustainability in the UK

Seafood production through aquaculture is in a unique position to contribute to healthy and sustainable diets and help to tackle the rising burden of chronic noncommunicable diseases and malnutrition in the UK, if environmental sustainability challenges and barriers to consumption are adequately addressed. Diversifying production, especially towards species of higher environmental sustainability, such as seaweed, mussels and sea urchins, and in particular through Integrated Multi-Trophic Aquaculture (IMTA), can serve a significant purpose towards bioremediation, while also allowing for product diversification and increased public acceptability of the industry. However, continued challenges to the commercial implementation of IMTA have hindered investment. This project will address barriers to the diversification of aquaculture systems in the UK by evaluating the contribution of IMTA to the nutritional value of aquaculture-produced seafood and to the environmental sustainability of the sector. To support aquaculture diversification, targeted interventions at the levels of business models, policies and consumer acceptance will be investigated.

To assess the nutritional contribution from IMTA (WP1), we will compare the total fatty acid budget on monocultures and IMTA systems, using data from desk-based reviews and direct data collection, from seaweed farms and culture trials of mussels and sea urchins, as input to growth models and mass-balance trophic models parameterised for fatty acids. Socio-economic values will be integrated into biophysical analysis by developing a bioeconomic model and assessing the potential social license to operate of IMTA systems (WP4), to comprehensively evaluate the provisioning, regulatory and socio-cultural ecosystem services linked to IMTA systems.

Further to describing the potential of IMTA to contribute to healthy and sustainable diets and ecosystems, the project will address implementation challenges by producers and consumers towards the diversification of aquaculture. To identify policy barriers to the adoption of IMTA and diversification (WP5), the project will assess the existing policy priorities and identify the underlying interests and incentives that affect the environment for reform towards IMTA. It will further explore the potential of seaweeds and invertebrates produced in integrated systems as candidates for nutrient and carbon trading credits. To assess the scope for improving consumer acceptance (WP3), the project will test the power of retail interventions in an experimental online supermarket with the aim of identifying seafood products with high market expansion potential. This assessment will be followed by a sensory experiment to evaluate the acceptability of novel products from IMTA, using facial recognition software to monitor the taster's displayed feelings during the task, which will help identify within each seafood category (e.g. algae) those varieties that consumers appreciate the most, therefore informing the research on business models. To address economic challenges to industry uptake, existing business models for aquaculture production in the UK will be described and a classification will be derived to identify how the these could be improved (WP2). This analysis will be complemented by stakeholder workshops to design innovative business models, using the Business Model Canvas. The workshops will explore new value propositions to the customers and opportunities for companies' market differentiation.

Through this interdisciplinary approach, the project will collectively assess and document the environmental, nutritional and economic benefits of IMTA and aquaculture diversification, providing the industry and policy-makers with insights to facilitate the transition to healthier and more sustainable aquaculture.