Gardeners aren’t usually the first people you’d think would be contributing to global warming. But if they use peat-based compost then that’s the case. According to the Royal Botanic Gardens at Kew, around 2.5 million cubic metres of peat are sold to commercial and amateur gardeners in the UK annually for compost.
So why is peat so important for the environment? Peat consists of decomposing plant material. As the plants were growing, they absorbed carbon dioxide. The CO2 was then ‘locked’ into the plant’s cell structure and stores as the plant turns to peat.
But when peat is dug up, the peat starts to decompose. It releases the CO2 back into the atmosphere again, increasing greenhouse gases.
The United Nations Environment Programme (UNEP) found in 2007 that the Earth’s estimated 988 million acres of peatlands are capable of storing about two trillion tonnes of CO2. That’s about a century’s worth of fossil fuel emissions. But peatlands are relatively small compared to their importance to the Earth’s eco-system. They only account for about 3% of the planet’s total surface.
The Head of UNEP, Achim Steiner observed that, “just like a global phase out of old, energy-guzzling lightbulbs or a switch to hybrid cars, protecting and restoring peatlands is perhaps another key ‘low-hanging fruit’ and among the most cost-effective options for climate change mitigation”.
Peat is also important because it supports many different types of flora and fauna. For example, plants like the sundew thrive in these conditions. It traps insects and digests them.
But the peat bogs are under threat, but not only from their destruction for commercial purposes. Researchers at the University of Wales, Bangor found that the world’s peat bogs are haemorrhaging carbon dioxide into the atmosphere. The problem is that as more CO2 is released, it stimulates further releases.
Repairing peat bogs has become more vital. For example, the National Trust in England, used a helicopter to spread heather seeds across the Bleaklow peat bog in the Peak District. It was hoped that the heather would return the bog to its previous lushness, thus turning it into a carbon storer again.
So next time you’re at the garden centre, think how amazing peat is and buy a peat-free compost.
