Biodegradable seaweed pouch design. Credit: Walilak University
Marine scientists in Thailand are placing tiny seaweed shoots inside 3D-printed bioplastic shelters because strong waves and hungry sea creatures keep destroying new transplants before they can grow roots.The trial is taking place in the waters surrounding Koh Lidi, two small islands within Mu Ko Vetra National Park in Satun Province. Seagrass meadows in the region are disappearing under severe environmental pressures. This loss has affected local fishing communities who depend on the meadows as nurseries for shrimp, crabs and fish. It has also devastated Thailand’s dwindling dugong population, which relies on seaweed as its main source of food.
Unprecedented numbers of dugongs have washed up dead along the Andaman coast in recent years.
Shielding shoots on the sea floor
Previous attempts to grow new seaweeds have encountered difficulties. Young shoots are easily swept away by ocean currents, buried in shifting seafloor sediments, or eaten by marine life before they take root on the seafloor.To solve this problem, researchers from Wallalak University in Thailand and Murdoch University in Australia designed a 3D-printed protective case.
Shaped like a small dome with an anchor, the unit is propelled directly to the sea floor with seaweed safely embedded inside.The dome features open holes along its sides, allowing roots to spread outward into the sand while keeping crabs, fish and turtles away from the tender shoots.
Bioplastics are designed to decompose
The pods are made from polyhydroxyalkanoate (PHA), a fully biodegradable plastic produced through bacterial fermentation using microbial strains native to Western Australia.“Bioplastics are produced through bacterial fermentation using microbial strains sourced locally in Western Australia,” said Dr Alexandra Golisia from Murdoch University’s Bioplastics Innovation Centre. “By designing the properties of the material, we can create a case that is durable enough to withstand marine conditions while remaining completely biodegradable.”Once the seaweed establishes a strong root system, the PHA Dome decomposes naturally without leaving plastic waste behind.The material can be produced at Murdoch University’s Bioplastic Innovation Center and the Joint Laboratory for Waste and Circular Economy at Naresuan University in Thailand.
Bioplastics are produced through bacterial fermentation using locally sourced microbial strains
Cross-border institutional support
The collaborative project is led by Walelak University doctoral candidates Patsakorn Jinchuai and Lionel Jude Girai. They are supervised by Professor Mulika Jarunsotasini and Professor Krissanadij Jarunsotasini, Directors of the University’s Center of Excellence for Environmental Informatics.The Thai team is working alongside Dr Gulisia, Professor Andrew McRae and Dr Samantha Vijoen from Murdoch University’s Bioplastics Innovation Centre. Financial support for the research comes jointly from the National Research Council of Thailand and the Murdoch Bioplastics Innovation Centre, with support from the Commonwealth Scientific and Industrial Research Organization (CSIRO).Professor McRae, Deputy Director of the Bioplastics Innovation Centre, spent more than twenty years working on mangrove restoration in Brazil before joining this project.“One of the biggest challenges in seagrass restoration is helping young plants survive long enough to establish roots,” Professor Macri said. “These biodegradable pods are designed to protect grown plants from waves, sediment movement and grazing animals during those critical early stages.”
Testing before field deployment
Researchers from Murdoch University recently visited Koh Ledi to survey the underwater site and meet the local research team.The 3D printed capsules remain in the prototype stage. Scientists are conducting safety checks and packaging tests before beginning physical field experiments in the ocean around Sutton County.Professor Jennifer Verduin, a leading expert on seaweeds and Vice-Chancellor Professional of Murdoch University’s School of Environmental and Life Sciences, is providing guidance for the project.“If successful, this technology could provide a scalable and environmentally friendly solution for restoring seagrass ecosystems in Southeast Asia and other coastal regions facing similar challenges,” Professor Verduin said.
Jennifer Verduin, a leading seaweed expert, will provide expert guidance and direction throughout the project.
Regional conservation efforts
The initiative around Koh Lady aligns with broader conservation strategies launched across Thailand to address accelerating coastal habitat loss. In response to the high dugong mortality rate along the Andaman Coast, Thailand’s Department of Marine and Coastal Resources, along with environmental organizations, has expanded satellite mapping and aerial drone surveys to monitor surviving dugong populations and map historical seagrass loss.
These high-resolution mapping projects allow researchers to identify high-priority areas where active replanting efforts have the highest chance of success.The choice of polyhydroxyalkanoate (PHA) for 3D printed horns is due to its performance in marine environments. Unlike traditional bioplastics such as polylactic acid (PLA), which require artificial composting conditions to decompose, PHA is consumed naturally by ocean-dwelling microbes.
In tropical waters such as the Andaman Sea, marine half-lives of PHA range from two months to less than a year, depending on hull thickness and surface area.
Microorganisms break down the polymer into carbon dioxide, water and natural biomass. This ensures that once the pod has completed its physical duty of anchoring the buds and preventing grazing, it completely disappears from the ecosystem without leaving synthetic plastic residue behind.
