Capturing the colour of carbon

A female spiny seahorse (Hippocampus guttulatus) shelters in a meadow of common eelgrass (Zostera marina) - Alexander Mustard/2020VISION

Steve Mewes, Policy & Campaigns Manager talks carbon capture, the difference between 'green' and 'blue' carbon, and the vital role the natural environment plays in mitigating the impacts of climate change.

The climate crisis now regularly makes the headlines, and rightly so. But there’s another crisis – inextricably linked – hiding too often unnoticed in its shadow: the massive, ongoing loss of nature. In the UK, 41% of species have declined since 1970 and one in seven are now threatened with extinction. The climate emergency has terrible ramifications for wildlife, but the loss of wildlife and wild places also makes the climate crisis worse.

Healthy natural habitats can store huge amounts of carbon, taking it out of the atmosphere and locking it away in soils and plant matter, sometimes for thousands of years. But many of our wild places are damaged, fragmented and threatened with further destruction. As these habitats are lost, carbon is released. To tackle the climate emergency, we need to protect and restore our wild places.

Oak tree

Oak tree - Amy Lewis

Green carbon

 

Carbon that is stored by ecosystems on land is known as green carbon. When you think about natural solutions to climate change, tree planting is probably the first thing that springs to mind. Trees absorb carbon as they grow, storing it in their trunks, branches and roots, so allowing woodlands to grow naturally locks up carbon and helps counter our manmade carbon emissions. But trees are only part of the solution; alone they are not enough. Nature has a plethora of other powerful natural climate solutions that currently receive much less attention.

Peatland is a type of wetland, made up of soil formed from slowly decomposing plants. Peatlands cover just 3% of the earth’s surface but store more carbon than any other habitat on land, with the UK’s peatlands alone containing 3.2 billion tonnes of carbon. Healthy peatlands also play a role in storing water, preventing drought and improving water quality, as well as providing a home for some wonderful wildlife, like the dazzlingly plumaged golden plover.

But damaged peatlands are a major source of greenhouse gas emissions. Peatland has to be wet to be healthy, and much of our peatland has been drained. At least 80% of the UK’s peatlands are damaged and may be releasing up to 23 million tonnes of carbon dioxide a year – that’s more than is absorbed by all our woodlands. Fixing them must be a priority.

Flowers in grassland

Flowers in grassland - Emma Bradshaw

The same is true for many other habitats: when healthy, they’re excellent carbon stores, but when damaged they release carbon. Grasslands soak up and store carbon in their roots and the soil but, between 1990 and 2006, an estimated 14 million tonnes of carbon dioxide was released by grasslands being put to the plough.

Blue carbon
 

Our oceans lock up even more carbon than the habitats on land, absorbing an estimated 20-35% of manmade carbon dioxide every year. We call this blue carbon, and it can be stored in plants, sediments and even the bodies of animals.

Saltmarsh

Saltmarsh edge with common glasswort (Salicornia europaea). - Terry Whittaker

Saltmarshes are superstars of the carbon storage world, absorbing carbon at a faster rate than either peatlands or woodlands. These coastal habitats also act as a buffer against erosion and as important breeding and feeding grounds for a host of birds and other animals.

Seagrass meadows are almost as impressive, responsible for 10% of the ocean’s total storage of carbon, despite covering less than 0.2% of the ocean floor. Carbon is also stored through the actions of marine life, from tiny phytoplankton that absorb carbon as they grow, to huge whales that carry carbon down to the seafloor when they die.

But our blue carbon solutions are threatened. In the UK, we’ve lost nearly 50% of our seagrass beds in the past 35 years, and we’re losing around 100 hectares of saltmarsh each year to development and rising sea levels. As these habitats are damaged, carbon is released, making the climate problem worse. Our seas are not as healthy as they should be, but even in their current state they store huge amounts of carbon dioxide. Imagine how much more they could hold if we restored them, bringing back more seagrass meadows, coastal marshes and the wildlife they support.

Somerset Levels

Somersel Levels - Paul Harris/2020VISION

Restoring the natural solutions

 

Clearly natural solutions have a big part to play in tackling the climate crisis, so restoring these damaged habitats and ecosystems must be a priority. The Wildlife Trusts are playing a leading role in making this happen, with projects around the UK improving, expanding and protecting the wild places that are key for capturing carbon. And here in Somerset, the Avalon Marshes on the Somerset Levels is the perfect example of what can be achieved when partners work closely with farmers and the community to protect a unique wetland.

The Wildlife Trusts are also championing a Nature Recovery Network – a coordinated, effective response that restores and connects habitats across the whole of the UK. Essentially, we need wild places to be more numerous, healthier and better connected. This broad, connected approach is vital in stopping the loss of nature and helping combat the climate crisis.

At a time when we are in desperate need of solutions to the climate emergency, it seems nature is ready and able to help…