Impact theme
Decarbonising hard-to-abate sector

Sector
Aqua

Affiliation
DTU Aqua

Stage

Team
Magnus Andreasen, postdoc, Project Lead and Technological Development
Colin Stedmon, Professor and Scientific Advisor

Why it Matters

Coastal sediments with low-oxygen conditions—have become significant emitters of the potent greenhouse gas methane (CH₄). In some regions, shallow water sediments produce more methane per area than many terrestrial habitats, making their mitigation crucial in combating climate change. Eelgrass meadows are globally recognized for their potential to become “blue carbon” sinks, but their expansion has been severely hampered by toxic, oxygen-deficient sediment.

Working on

ZosteraGrids offers a transformative solution, where they install modular, stainless-steel grids in the seafloor, connected to corresponding grids in oxygen-rich surface waters. This creates a favorable electrochemical pathway for sediment bacteria, reducing methane production by up to 99%. By also attaching eelgrass shoots (Zostera marina) to the grids, they also foster carbon uptake and potentially long-term carbon storage. In essence, ZosteraGrids materializes the goal of converting degraded, methane-emitting sediment into a healthier substrate.