Now, architects and marine scientists at the University of Hong Kong (HKU) have joined forces to develop a novel method for coral restoration. The new method sees specially designed 3D-printed artificial ‘reef tiles’ implanted in the Hoi Ha Wan Marine Park in Hong Kong.
"The Marine Park is a local biodiversity hotspot accounting for more than three-quarters of reef-building corals in Hong Kong and more than 120 fish species. However, in recent years, gradual deterioration of the coral habitat, a process known as bioerosion, coupled with coral bleaching and mass mortality events in 2015-2016, are putting the future of the coral community at risk," a press release by HKU said.
The newly engineered HKU 3D printed terracotta ‘reef tiles’ were installed in about roughly 430-square-foot (40m2) in total at three selected sites within the Marine Park, including Coral Beach, Moon Island, and a sheltered bay near the WWF Marine Life Centre. There, they will provide a useful structurally complex foundation for coral attachment. They will also serve to prevent sedimentation.
In total, 128 pieces of reef tile with a diameter of 23 inches (600mm) were printed. They were specially created through a robotic 3D clay printing method with generic terracotta clay.
Once designed, they were then fired at 2057 degrees Fahrenheit (1125 degrees Celsius) in order to be set. The materials used for their creation are known to be more eco-friendly than traditional coral reef restoration methods.
Three coral species were chosen for the research: Acropora, Platygyra, and Pavona. Together these species will create a diverse habitat for other marine species.
The team now hopes to create additional new designs for coral attachment and that this new method for artificial reef tiles will help to conserve biodiversity and restore degraded coral reef systems.