Broads Uncovered: Peat

Peat is not only an amazing type of soil but also the reason the Broads exist. Twice as much carbon is stored in the world’s peatlands than in the rainforests and it underlies 30% of the Broads National Park. Our local and national peatlands have been used through the centuries but it has become increasingly important that we protect them to prevent their stored carbon being released into the atmosphere and adding to the global warming crisis.

What is peat and where is it found?

Peat occurs throughout the world (Figure 1) and is a type of soil, rich in organic matter, that forms in very wet areas where there is a lot of vegetation such as marshes, fens, bogs and swamps. As plants die they fall into the water where they fail to fully decompose due to low oxygen levels and few decomposing organisms. This layer of semi decomposed vegetation is added to each year, getting thicker and thicker and more compressed, ultimately forming the carbon rich soil – peat.

The peatlands in the Broads National Park have formed in alkaline conditions because the region’s water filters up though underlying chalk. This creates alkaline fenland habitat rather than the acidic peat bog habitat of Scotland and Ireland. In the Broads, peat is estimated to form at a rate of 2.7mm/year and can be over 10m deep in some areas!

Why is Peat important?

Peat is important for a number of reasons – biodiversity, flood defence and as a carbon store. It is estimated that the amount of carbon stored in the world’s remaining peatlands is 550 billion tonnes. There’s no way we want all that stored carbon released into the atmosphere, it’s best it remains safely locked away underwater and underground in our peatlands.

It is estimated there is 12-14 million tonnes of carbon stored in the peatlands of the Broads National Park.  If this 12-14 million tonnes is burnt or dried it would release the same amount of carbon dioxide into the atmosphere as the annual output from 38 coal power stations.

Global Warming and Peat

Most people know that burning fossil fuels – coal, oil and gas – increases the levels of carbon dioxide, CFCs and other pollutants in our atmosphere leading to global warming. The increase in the overall temperature of the Earth’s atmosphere caused by global warming results in a number of environmental problems around the world, not least the melting of the ice caps. But how many people know that when peat is burnt it also releases the same amount of greenhouse gases as fossil fuels? Hence, the need to stop using peat and to leave our peatlands alone.

What do we use peat for?

Throughout history people have used peat, like wood, as something to burn to cook on and heat their homes etc. It is dug up out of the wet marshy land and laid out to dry where it hardens, before being burnt. Power stations can also be fuelled by peat – Ireland still has three of these in operation. More recently peat has also been dug up to be made into the compost we buy at garden centres and supermarkets. Peatlands, especially low lying ones, are also drained to make way for agriculture – just think of the Fens in Lincolnshire – or for humans to build on.

By digging the peat up, to burn, or use as compost, or by draining it, the peat’s organic matter (partially decomposed vegetation from thousands of years ago) is exposed to air, decomposers and heat and breaks down releasing the stored carbon into the atmosphere.

Peat in the Broads National Park

Ironically, the 63 broads (lakes) that give the National Park its name are in fact the flooded pits and “quarries” left behind from Medieval peat diggings! This was proved from extensive surveys conducted by Dr Joyce Lambert in the 1950’s.

Peat was dug out of the ground by hand using a variety of different shaped shovels and spades and was done on an industrial scale. Take some time to look at a map or google earth to see the size of Hickling Broad and Barton Broad. The peat was then air dried before being hauled by boat or horse and cart to Norwich and the other towns and villages for sale. It is estimated that 25 million cubic metres of peat was dug out from the region.

Once abandoned, the peat pits flooded as sea and groundwater levels rose, forming the lakes that we know of as the Broads today. These in turn became home, through time, to some of Britain’s most remarkable wildlife.

The peatlands of the Broads National Park support the biodiversity that is found in the fen, grazing and reed bed habitats. Plants adapted to growing in the conditions created by peat soils flourish and in turn provide food and habitat for a range of animals. Peat is able to absorb and retain huge amounts of water, a bit like a sponge, and ensures that even in the driest of summers water is still available to the plants and animals that live on it.

Key Message:

Peatlands, like those in the Broads National Park, need our protection from being:

• Dug up to burn or use as compost for our gardens.
• Drained for agriculture or development.

You can help by:

• Thinking of the melting ice caps and spreading the word about how we need to protect peatlands to keep their huge store of carbon out of our atmosphere.
• Make a pledge to buy Peat Free Compost (it works just as well) at garden centres and supermarkets. Peat Free compost makes use of ingredients that don’t cause habitat destruction and Global Warming. Alternatively, make your own Peat Free Compost!
• No space for a compost bin? Then see if you can recycle your food and garden waste through your local council. Food and garden waste that is sent to landfill rots and releases methane – a harmful greenhouse gas that is 25 times more potent than carbon dioxide.
• It is possible to generate money from peatlands without draining them. Reedcutters have been harvesting reeds for thatching houses for generations.  Look out for and support our local reed cutters and thatchers.