We’ve all tried it, hopping from one side of a little bog to the other by keeping to the protruding lumps of moss, only to find ourselves sinking knee-deep in slime. Although terrible underfoot, peat moss is one of the most reliable stores of carbon on Earth. At present, peat mosses cover ten per cent of all land in Norway and Russia and another 13 per cent of all land in Canada. In these bogs, peat sequesters as much as 550 billion tonnes of carbon.
Sphagnum species thrive in wet areas and spread across vast regions of the northern hemisphere. Empty plant cells in the living and dead plants can retain 25 times their dry weight in water, allowing the moss to spread from wet to drier land. Sponging this water together creates the bogs, where biological material can be broken down anaerobically (without oxygen). Breaking down organic material in this way keeps more carbon than it releases, storing it below ground in a layer of peat.
‘No plant genus is more important as a carbon balance on Earth than peat mosses,’ says Professor Hans K. Stenøien, Professor of Evolutionary Biology at the Norwegian University of Science and Technology (NTNU) University Museum in Trondheim. ‘Peat stores at least a third of all the carbon on land.’
Unaware of the ecological value of bogs, few people have vouched for their conservation in the last few centuries. Because of this, thousands of miles of bogs and sphagnum habitat have been drained to make way for tree plantations and farmland.
Scotland’s Flow Country, the largest blanket bog in Europe, was ploughed in large areas for tree plantations during a period of high unemployment in the 1970s. Similar stories emerge from Norway, where it is estimated that around 25 per cent of peat land has been destroyed. In Canada, vast stretches of peat bogs are still threatened by oil sands development.
A warmer climate might effect how much carbon is sequestered by permafrost sphagnum mosses. When permafrost melts, locked up carbon is released into the atmosphere, though how much and how quickly remains to be seen. Should it all be released, there is enough carbon in northern permafrost to exceed the amount that has been released by burning fossil fuels.
In order to gain political support for the protection of peat mosses, NTNU University Museum is collaborating with a team of international partners to understand how they interact with carbon. As well as researching the binding rate and accumulation of carbon, they will be investigating the bog restoration and drafting protection plans to conserve them for future carbon sequestration.