Meliora: a podcast from the Sustainability & Resilience Institute
Welcome to the Green Gown Award winning Meliora Podcast from the Sustainability and Resilience Institute at the University of Southampton!
This podcast explores the greatest and most wicked problem that is sustainability, whilst looking at how we are collectively addressing this critical global challenge.
Sustainability needs to be addressed by understanding how the economy, society, culture, politics and environment intersect, and this is the focus that informs each episode of the Meliora podcast.
In each episode, host Professor Simon Kemp and guest hosts are joined by a variety of guests, including academics, students, staff, researchers, alumni, community groups and business leaders.
The aim of the podcast is to shine a light on the vast range of topics surrounding sustainability and to allow listeners to learn about the critical challenges we face, as well as how they can be part of the solution. We also ensure our fantastic students have the opportunity to share their brilliant work with the world.
Podcast host: Professor Simon Kemp, Deputy Director of the Sustainability & Resilience Institute, University of Southampton
Podcast editors: Jack Dinham, Ellie Howell, Mya Harvey, Lily Killner, Sophie Green, Libby Kale, School of Geography and Environmental Science, University of Southampton
Podcast communications: Tyler Domone-Hollands, Hannah Parish, Alexander Ayerst, Maya Stevens, University of Southampton
Please do get in touch to discuss this podcast and any of the issues we raise by emailing sri@soton.ac.uk
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Meliora: a podcast from the Sustainability & Resilience Institute
Lili-Mei Judd: Nitrogen cycling in a crab-polychaete-macroalgae IMTA system: implications for waste recycling and water quality
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Lili-Mei Judd (MSci Marine Biology) joins us to discuss whether a simplified crab–polychaete–macroalgae integrated multi-trophic aquaculture (IMTA) system could reduce nitrogen accumulation to biologically safer levels than crab monoculture through internal waste recycling. Within fed aquaculture, including crustacean culture, crabs excrete nitrogenous waste as a direct result of protein catabolism, this accumulates within the water system with direct welfare consequences for the cultured species and if discharged to local water bodies can exceed the assimilative capacity and drive algal proliferation and eutrophication.
In this system I designed, fed crab species were co-cultured with extractive organisms from complementary trophic levels so that organic and inorganic nitrogen waste from crab component became feed inputs for the polychaete worms and macroalgae compartments, being recycled within the system rather than discharged as pollution.
This project addressed SDG 12: Responsible consumption and production and SDG 14: Life below water to ensure that we sustainably use marine resources in aquaculture to ensure resilient and nature-based food systems. Three sequential 10-day tank experiments were conducted using native UK species of triplicate crab monoculture tanks and triplicate integrated systems containing European shore crab (Carcinus maenas), common ragworm (Hediste diversicolor), and serrated wrack seaweed (Fucus serratus) and daily water-column dissolved inorganic nitrogen and nitrogen speciation were measured. Here IMTA was shown to reduce waste release and its associated environmental impacts compared to crab monoculture.
This project has given me hope that when you observe natures processes and interactions within an ecosystem and then manipulate through science into our food systems, you will get a most productive system- it is a time to bring more circularity to how we produce our food. If you would like to learn more about this project, please follow the link here to the PDF: Nitrogen cycling in a crab-polychaete-macroalgae IMTA system implications for waste recycling and water quality
Episode guest: Lili-Mei Judd, MSci Marine Biology
Episode host: Prof Simon Kemp
Episode producer and editor: Ellie Howell
The Meliora Podcast Student Research Symposium is part of the 2026 Student Takeover Season where we celebrate the fantastic sustainability research work of our Undergraduate Students.
