Recently, I had the pleasure of interviewing Professor Amy Wagoner Johnson, a pioneering materials scientist involved in a global initiative focused on coral reef restoration, on my podcast, Redefining Energy — Tech. This conversation highlighted her unique transition from printing human tissues to applying her expertise to coral ecosystems.

Michael Barnard (MB): Welcome back to Redefining Energy — Tech. I’m your host, Michael Barnard. Today, I’m excited to speak with Professor Amy Wagoner Johnson, a materials scientist based at the University of Illinois Urbana-Champaign, which, interestingly, is far from any ocean. Despite being landlocked, she's spearheading a remarkable project aimed at restoring coral reefs through innovative 3D-printing techniques. Welcome, Amy.

Professor Amy Wagoner Johnson (AWJ): Thank you for having me, Michael.

MB: I’m eager to learn about your journey from Urbana-Champaign to coral restoration. Can you share your background with us?

AWJ: Certainly. As a materials scientist in a mechanical engineering department, my focus shifted from traditional material science to exploring bone repair through scaffolds after completing my PhD. This area is closely related to tissue engineering. My work involved designing microstructures to release drugs that promote bone regeneration. Collaborating with a colleague from Jamaica, we began discussing the potential for 3D-printing in coral restoration, which led us to attend a coral conference to present our ideas.

Upon engaging with coral scientists, I realized we needed to take a step back and investigate the materials that would effectively support coral larvae in their development. This exploration aimed to identify surfaces that would encourage larvae to settle and transform into coral polyps, inspired by concepts from our tissue engineering projects.

MB: That sounds fascinating! I believe you received a substantial grant to support this research.

AWJ: Yes, we secured an $825,000 grant from the National Science Foundation (NSF). Initially, I faced challenges finding funding, as many program managers felt the idea didn't fit their areas. However, when NSF introduced a call for convergence research projects, I collaborated with my mentor and proposed a project focused on engineering materials for coral restoration. This led to one of NSF's first convergence research awards.

MB: Why is coral so crucial to our ecosystems?

AWJ: Coral reefs are vital for several reasons. They provide coastal protection from storms and serve as habitats for diverse marine life, forming the foundation of food chains. Healthy reefs support various fish species, including those important for human consumption, and also contribute to local economies through tourism. If reefs deteriorate, we risk losing these benefits, along with the biodiversity they support.

MB: It’s alarming to think about the threats facing coral reefs today. What are the main challenges they encounter?

AWJ: Climate change is a significant threat, causing rising ocean temperatures and acidification. Additionally, coastal development and pollution, such as fertilizer runoff, harm coral health. Overfishing is another factor that disrupts the balance of marine ecosystems. While climate change is a global issue, local factors like overfishing can be managed more effectively.

MB: The impact of human activity on coral is profound. Can you explain the effects of ocean warming and acidification on coral polyps?

AWJ: Corals have a symbiotic relationship with algae, which provide them with essential nutrients and color. When water temperatures rise, corals expel these algae, leading to bleaching and starvation. This process exposes the coral skeleton, making it vulnerable to invasive algae and compromising its structure.

MB: Coral reefs take a long time to grow. How does this slow growth rate impact restoration efforts?

AWJ: Yes, building a significant coral reef can take thousands of years. While it may seem discouraging, we can explore methods to simulate reef conditions and support new coral growth. It’s crucial to combine various strategies to address the challenges we face.

MB: With so many factors at play, it sounds like your research is multi-faceted. Can you elaborate on the materials you’re exploring for coral restoration?

AWJ: We aim to develop calcium carbonate-based materials for 3D-printing that can mimic the coral skeleton. Our research involves experimenting with lime mortar and adding materials that can slowly release beneficial ions to promote larval settlement. We’re also investigating the role of crustose coralline algae, which appear to influence larval behavior and growth.

MB: This research seems to require a deep understanding of fluid dynamics as well.

AWJ: Absolutely. Fluid dynamics is vital for understanding how larvae interact with their environment and settle on substrates. We built a flume to analyze how different surface features affect larval behavior in water.

MB: It’s fascinating how interconnected these systems are. As we tackle coral restoration, we must continue to innovate and adapt to the challenges presented by climate change.

AWJ: Indeed, collaboration across disciplines is essential for finding effective solutions.

MB: Thank you for sharing your insights, Amy. Your work is crucial for the future of coral reefs and the ecosystems they support.