Seaweed fuels methane production on sandy shores
Seaweed on sandy shores fuels oxygen-tolerant microbes that produce methane, challenging assumptions about coastal ecosystems' climate role.
Why it matters
- Seaweed on sandy shores fuels methane-producing microbes, challenging long-held assumptions about coastal ecosystems.
- Methane production from coastal zones may offset some climate benefits of "blue carbon" strategies.
By the numbers
- Methane concentrations in shallow coastal waters were up to 1,900 times higher than expected.
- Methane release rates from coastal sites are comparable to or exceed those of wetlands and salt marshes.
The big picture
- Methanogenic microbes can survive and remain active even after repeated exposure to oxygen.
- Methane production is higher where seaweed and seagrass debris accumulates.
- Findings challenge "blue carbon" strategies and suggest that coastal methane emissions may be higher than previously thought.
What they're saying
- "This new finding not only challenges a fundamental assumption in marine science, but calls into question what we thought we knew about the role of sandy coastline ecosystems in greenhouse gas production." — Professor Perran Cook, Monash University
Caveats
- Study focused on specific sites in Australia and Denmark; methane release rates may vary with geography and local conditions.
- Lab experiments are simplifications of complex coastal dynamics.
What’s next
- Researchers plan to study how different species of seaweeds and ocean conditions affect these microbes.
- This will help better predict how much methane is being produced in the coastal zone.