World-first project reveals urgent need to protect the UK’s seabed

Sea Grass (c) Paul Naylor

Todays Blog is written by Jean Duggan, Marine Policy Officer, where she explains the importance of Blue Carbon in our seas and why action is needed to protect it if we are to tackle the nature and climate emergency.   

A new series of reports, collectively called the Blue Carbon Mapping Project, has revealed the huge amount of carbon stored in UK marine habitats and highlights the urgent need to increase protection of the seabed within and without Marine Protected Areas. The partnership project was completed by the Scottish Association for Marine Science (SAMS) on behalf of WWF, the RSPB and The Wildlife Trusts. 

The study covers several regions: the English Channel and Western Approaches, the Irish Sea and Welsh Coast, and Scotland. A pilot project undertaken earlier covered the North Sea. There are reports for each region as well as a UK synthesis report. Together they provide the first estimate of the carbon stored and sequestered by marine habitats (also known as ‘blue carbon’) in UK seas. The project means the UK is the first country to map and estimate the amount of carbon stored in its seabed habitats. 

Blue carbon habitats include seabed sediments (made of mud, silt and sand), vegetated habitats (seagrass meadows, saltmarshes, kelp forests and intertidal seaweeds), maerl beds and biogenic reefs, such as mussel beds and honeycomb worm reefs. These marine environments play a crucial role in the carbon cycle in different ways, from capturing carbon directly through photosynthesis to trapping carbon from other sources, and to storing vast amounts of carbon. They are therefore key to addressing the intertwined climate and nature crises. 

 

Mudflats in Dumfries and Galloway (c) Mark Hamblin 2020VISION

The study found that a massive 244 million tonnes of organic carbon are stored in UK seas, with 98% of that total stored in sediments including mud and silt. It also explored the amount of blue carbon stored specifically in Marine Protected Areas (MPAs) and found that these account for 43% of the total organic carbon found.  

The analysis considers only the top 10cm of the seabed habitats, so the findings represent a fraction of the overall carbon stored. The top layers of sediment are however the most recently deposited and most at risk from human activities. Physical disturbance to the seabed, including from bottom trawling and offshore development, are identified as the most widespread threats to blue carbon stores. 

 Understanding more about the UK’s blue carbon can enable policymakers to strategically plan activities in UK seas to minimise harm to the marine environment. This can help achieve climate and biodiversity goals, including net-zero and protecting 30% of seas by 2030. 

 In light of this research, the RSPB and its partners are calling for multiple actions to be taken to secure a healthier marine environment that meets both biodiversity and climate needs: 

1) Better management of MPAs: 

  • Ensure that all MPAs are protected from destructive activities that damage blue carbon habitats and threaten marine life. 
  • Account for both carbon and biodiversity in designating new protected areas, to support ecosystem resilience and the role seas play in climate mitigation. 

 2) Improved strategic planning of activities in UK seas 

  • Consider blue carbon in UK marine plans, avoiding damaging activities in MPAs and other key areas for blue carbon and wildlife that are not protected. 
  • Minimise the impacts of fishing and developments by undertaking blue carbon impact assessments. 
  • Support a just transition for fishing industries away from activities that damage the seabed. 

 3) More investment and research on protecting blue carbon 

  • Allocate funding to restore habitats including seagrass beds and saltmarshes. 
  • Support research and monitoring of blue carbon dynamics. 
  • Add seagrass and saltmarsh to the Greenhouse Gas Inventory to track and monitor emissions. 

 

Langoustine in Carbon rich sediment (c) Paul Naylor

It is critical that we accelerate efforts on land to tackle the nature and climate emergency and this research shows that we must not underestimate the role of UK seas in this challenge. Together, the reports are a gamechanger for our knowledge of the marine environment and should provide a valuable asset for decision-makers to factor into their thinking. To meet net zero and stop biodiversity decline we must work with nature, not against it. This means restoring habitats, properly planning offshore development, and investing in protected areas to safeguard wildlife and keep blue carbon locked up.  

Learn more from our video here.