Australian researchers are testing biodegradable, 3D-printed structures to protect budding wetland species while slowing coastal erosion.
Supported by Beach Energy, scientists from Deakin University's Blue Carbon Lab in Victoria are placing mangrove seeds in net-like frames in coastal locations in Port Phillip Bay and Western Port Bay to promote their growth.
The structures slow water flow and encourage soil accumulation, and are particularly beneficial in areas that have experienced erosion or harsh environmental conditions hindering roots from establishing themselves.
The 3D-printed lattice, made of potato starch from industrial waste, biodegrades within two to 10 years.
Over the three-year Regenerating Our Coasts program, researchers will be monitoring the survival and growth of mangroves.
Deakin University's Stacey Trevathan-Tackett said if the trial was successful, the structures could benefit many coastal areas and act as a flood defence.
"We're looking at areas that might have a bit of erosion or something, or they've had a bit of restoration but the plants are growing very slowly," Dr Trevathan-Tackett said.
"Anywhere that kind of has that wave energy … where they are struggling a bit."
Maintaining a healthy environment
The lattices are printed in a facility in the Netherlands before being transported to Australia.
Here, researchers insert seeds into the lattice, or place the structures into the coastal area where seeds have already been planted.
Dr Trevathan-Tackett said regenerating damaged coastlines was vital for maintaining a healthy environment.
"Salt marsh and sea grasses are really amazing … they protect our coastlines from erosion. They are hotspots for biodiversity," she said.
"A lot of organisms depend on these ecosystems for part or all of their lifetimes and these ecosystems also draw down atmospheric carbon stored in their soils."
Replacing plastics or concrete
Many restoration projects use plastics or concrete to protect seedlings, but this tampers with and pollutes the natural environment.
"Sometimes when you remove [the supporting structures] they might disturb the plants themselves," Dr Trevathan-Tackett said.
"They're there for a while to help stabilise the sediment, stabilise the roots, let the plants grow, and then eventually they'll degrade themselves."
Researchers will also observe which conditions promote regeneration, including the type of soil, the role of roots in helping plants flourish, and the water conditions.
Citizen scientists are collecting data by monitoring the seeds and measuring their survival and growth.
"Engaging with communities through education and knowledge exchange means that more people understand the problem and support what we're doing to solve it," Dr Trevathan-Tackett said.
Beach Energy's Linda French accompanied the citizen scientists when they observed the trial site in Western Port Bay and said it was a "thrill".
"It was a great opportunity for us to go and actually see how they measure the build-up of sediment, whether the seed has taken, what its growth rate was, what area it was located in." Ms French said.
