The State Key Laboratory of Marine Pollution (SKLMP) at CityU was awarded the prestigious Gold Award at the Hong Kong Green Innovations Award (HKGIA) as part of the 2022 Hong Kong Awards for Environmental Excellence (HKAEE). This recognition highlights the remarkable achievements of their team in the field of green innovation. Organised by the Environmental Campaign Committee of HKSAR Government, the HKAEE is renowned as the city’s annual “Oscars of Environmental Protection.”
Led by Professor Kenneth Mei-yee Leung, College of Science’s Associate Dean (Research and Postgraduate Education), Chair Professor in the Chemistry Department and Director of the SKLMP at CityU, the team comprises Dr. Chi Chiu Lo, Thea Bradford, and Rainbow Leung from the SKLMP, as well as Dr. Juan Carlos Astudillo, Assistant Professor in the Applied Sciences Department at Hong Kong Metropolitan University, and Professor Chi Sun Poon, Chair Professor and Head of the Department of Civil and Environmental Engineering at The Hong Kong Polytechnic University. Their ground-breaking innovation, titled “Enhancing Intertidal Marine Biodiversity on Artificial Seawalls by Novel Eco-tiles”, clinched the top prize.
Conventional seawalls, typically made of concrete and granite boulders, lack the necessary structure to support the settlement and growth of marine organisms. The team revolutionised the concept of seawalls with a two-fold innovation. First, they developed an eco-friendly concrete mix, comprising 40% waste materials, including fly ash from incineration of sludge and dredged marine sediment from navigation route maintenance. This novel concrete mix has high compressive strength (39 MPa) and low surface pH (about 10), which is crucial for sea defence structures and marine larval settlement, respectively.
Second, incorporating ecological theory, the team created eco-tiles with water retention capacity and various microhabitats, such as grooves, holes and crevices of different sizes. These features not only offer refuge for marine life, but also effectively provide shade and lower temperatures during low tide in summer. Twelve-month trials conducted in Sai Kung, Ma Liu Shui and Tuen Mun demonstrated that the eco-tiles significantly reduced the average surface temperature by 2°C and increased biodiversity by 80% compared to conventional seawalls.
Building on this success, the project team established a start-up called “afterNATURE” through CityU's Hong Kong Tech 300 programme. Leveraging their expertise, they developed a range of eco-engineered products, including eco-tiles, eco-panels, tidal pools and eco-blocks, with a view to revitalising existing seawalls and breakwaters to enhance marine biodiversity and ecosystem services, thereby transforming manmade seawalls into living shorelines. These products have been adopted by the HKSAR Government for numerous seawalls in Causeway Bay, Tsuen Wan, and Lamma Island, among others. More recently, their products have gained traction in coastal restoration projects in Korea, Mainland China and the United States.
“I’m delighted to receive this recognition alongside the team,” said Professor Leung. “The HKGIA is a significant affirmation of our research efforts in ecological restoration and our support for the HKSAR Government in implementing eco-shorelines to enhance marine biodiversity. By utilising waste materials in our eco-tiles, we minimise cement usage and reduce the carbon footprint. Transforming waste into useful products for ecosystem restoration also helps reduce waste disposal and extends the service life of landfills.”
In addition to the HKGIA, the team's eco-tile invention has received several international accolades this year, including the Special Prize (Prize of the Korea Invention Promotion Association), the Gold Medal with Congratulations from the Jury at the 48th Geneva International Exhibition of Invention in Geneva, Switzerland, and the Gold Medal in the Asia International Innovative Award at the Asia International Innovative Invention Exhibition, held in Hong Kong, China.
This article originated from CityU NewsCentre.
