UK’s muddy saltmarshes vital to tackle climate change

According to a recent WWF report, the UK’s saltmarshes are crucial “sinks” that absorb greenhouse gases in their mud layers.

Despite significant losses due to agriculture, the organization highlights these habitats as underappreciated allies in combatting climate change.

WWF calls for these tidal environments to be included in the national carbon inventory, documenting emissions and removals each year.

This official acknowledgment might encourage more restoration and protection efforts for such areas.

Collaborating with the UK’s Centre for Ecology and Hydrology, WWF has established solar-powered monitoring stations on Hesketh Out Marsh, a restored saltmarsh in North-West England run by the RSPB.

Measurements showed that the marsh’s plants absorb more carbon dioxide during the summer than they emit in the winter, revealing their critical role in carbon management.

This research builds on earlier studies assessing carbon levels in the marsh’s mud.

The team set up equipment on a sturdy 2.5m scaffolding tower, ensuring it remained safe from tidal saltwater.

With WWF’s ocean conservation specialist Tom Brook guiding, we navigated the tall grass to explore the research site.

At low tide, the vast grassland obscures the sea, scattered with driftwood and plastic debris, alongside an overturned boat.

“During spring and summer, the vegetation grows densely, layering and decomposing to capture carbon in the soil,” Tom remarked. “Contrary to traditional teachings about trees, it’s the mud here that serves a similar purpose for carbon storage.”

“The mud performs just as crucial a role in mitigating climate change as trees do.”

WWF’s inaugural findings are published in a report titled The Importance of UK Saltmarshes, co-published with an insurance firm interested in using these habitats to mitigate coastal flooding.

Since 1860, about 85% of the UK’s saltmarshes have been lost, many drained in favor of agriculture.

Hesketh Out Marsh, now managed by the RSPB and restored by re-flooding, is a thriving habitat filled with diverse bird species such as avocets, oyster catchers, and black-tailed godwits, which forage for food and nest among the lagoons and streams.

Researchers aim to leverage these findings to advocate for the restoration and preservation of more of these vital buffer zones.

Alex Pigott, the RSPB warden at Hesketh Out Marsh, emphasized, “The mud here is essential; it’s a vital resource for birds.”

With a variety of bill shapes, marshland birds effectively feed in the tidal mud.

“These sites not only act as natural flood barriers but also play a role in carbon storage,” added Ms. Pigott. “Restoring any of these habitats would be a significant step forward for nature.”