Moss-ive Carbon Storage!

Did you know that moss can store carbon?
Mosses are extraordinary organisms that are efficient in storing carbon, but also act as water purifiers and a habitat for lots of wildlife. Peat mosses (the Latin name is Sphagnum), in particular, are very important as they are found in bogs where they are able to keep the peatland moist.
A Sphagnum carpet (photo T.V. Callaghan)

Sphagnum and cotton grass in a bog pool (photo T.V. Callaghan)
What is peat and why is it so important for the environment?
Peat is a layer of organic matter created by vegetation that is partially decayed that has accumulated over many, many years. Not all peatlands are now wetlands, but they were when they were created. Peatlands have the most efficient on-land carbon storage in the world, storing more carbon than all the forests on Earth combined even though they occupy only 3% of the land surface. 20% of Siberia's land is covered by peat, but in the high-Arctic peat mosses are absent.

If the peatlands dry out, are burned by wildfires, drained or exploited for garden humus, decomposition increases and the carbon is converted to the greenhouse gas carbon dioxide contributing to climate change.

That's where the peatmoss comes in! The moss covers the peatland keeping it nice and moist throughout the seasons as peat mosses can hold 20 times their own weight in water depending on the species. The accumulating dead and decomposing moss increases the depth of peat helping it to "grow". Healthy peatlands remain active for many thousands of years and can continue to store and absorb carbon from our environment despite losing some carbon as methane in ponds.
Photos: T.V. Callaghan
What can we do to protect peatlands and mosses?
It is essential that peatlands are protected in order to safeguard these massive carbon stores! Some great ways to ensure the protection of these habitats are to spread awareness of the importance of peatland, prevent more agriculture and draining of these areas and restore existing peatlands by flooding. Did you know that Heathrow airport off-sets some of its carbon footprint by flooding and restoring peatlands!

Soil Organic Carbon Stocks
in the Russian Taiga
Did you know that?
Decomposition of dead plants is slower than growth so carbon accumulates in the arctic soils, particularly in wet areas
Permafrost soil contains twice as much carbon as is currently in the atmosphere
In wet areas, microbes "breathe out" methane instead of carbon dioxide and methane is a more powerful greenhouse gas
Carbon is released all the time through microbial respiration but can be released dramatically through tundra and forest fires
Scientists measure carbon in the soil by taking samples by digging soil pits or by coring columns of soil and then taking the soil back to the laboratory to measure the carbon

Get active!
Dig in your garden or somewhere else and then look at the photos in Story 6.3. Which does your soil most closely resemble?
If you don't have a garden, visit a forest/ park but make sure you have permission to dig a hole and that you cover it afterwards. Better still, find an exposed bank where you can see already what is under the vegetation.
What can you identify in different layers of soil. Can you see different plant remains? You should be able to see leaves at the top that are easily identifiable. As you dig through the layers, you should be able to see fewer and fewer identifiable leaves – that is because they are decomposing and the plants are being broken down by microbes until they reach a stage when only difficult to break down chemicals remain and decomposition slows down so that carbon is stored.
Organic matter production — Watch the movie. Try it at home!
Then find some mosses in your garden, on a path or on a wall. Lift up the moss, and peer underneath to see if you can see any black material. Can you? The black material is partially decayed plant matter, like dead stems – absorbing carbon dioxide, just like a peatland.
Carbon storage in action: Find some mosses in your garden on a path or on a wall, look underneath and see if there is any black material which is dead stems storing carbon.