04/04/14 - The Chat Moss Project

This seminar, given by Elspeth Ingleby (uk.linkedin.com/pub/elspeth-ingleby/47/42/301), was about Chat Moss (https://www.facebook.com/pages/The-Chat-Moss-Project/329943177133245) at the outer edge of Manchester, and the plans to restore this lowland raised bog to its original condition. 

Red marker indicates where Chat Moss is

Having worked at Lake Vyrnwy for the last 3 years, this talk promised to be very interesting to me. Lake Vyrnwy has thousands of hectares of raised blanket bog and I've helped restore small areas of this, so I assumed lots of the information from Elspeth would be comparable. However, I was very wrong.

Chat Moss has several different areas of bogs that have been separated over time through development and agriculture. By 1845, only 50% of the original extent of raised bog were left, most having been lost to agricultural land reclaim. The bog that did remain was being extensively used for peat extraction, and so those areas left were in a very poor state, compared to when it was in peak natural condition. By 1978 only 5 hectares of the original 2500 remained! However, more recently, conservationists have realised the importance of this rare habitat and have restored large areas so that there is now 300 hectares of good quality bog.

Unfortunately, although the habitat is good and healthy, the peat below this (that has been extracted for hundreds of years) is nothing like as deep as it was before humans began to change the habitat. It will take thousands of years to build the peat up again, and it is unlikely that conservationists will be able to protect the area from development for that long, especially with the ever growing human population.

What is a lowland raised bog?

This is an area where the drainage and nutrient content are so poor that most plants can't grow. Sphagnum mosses take hold and begin to grow within these areas. Over many thousands of years, the dead Sphagnum builds up to create peat and fills in the poorly drained hollow.

Formation of a raised bog [http://www.wesleyjohnston.com/users/ireland/geography/bogs.html]

This graphic shows the history of a particular bog in Ireland, but demonstrates the history and formation of most lowland bogs. There is a permanent layer of water trapped between the peat and the overlying Sphagnum that gives the area its boggy quality. The vegetative composition is extremely specialised to the poor nutrient availability characterised by this habitat. Therefore areas like this need to be protected if these species are to be maintained in Britain.

5 of the 120 species in the Sphagnum genus

Mossland destruction

The destruction of the original 2500 hectares of bog was mainly caused when the area was drained. Government schemes were put in place to encourage farmers to dig large drainage ditches through these areas, and then use the drained land for agriculture. This process happened across the country, including at Chat Moss and Lake Vyrnwy. The process was successful at Chat Moss and meant that vast areas of bog were destroyed. Over 99% of the original mosslands have been lost in the Lancashire, Manchester and North Merseyside areas. It was interesting listening to these facts having worked at Lake Vyrnwy. 

At Lake Vyrnwy drainage ditches were also dug...however they did not work. The area remained wet and unusable for agriculture, but the run off was much faster. To improve water quality and slow down direct drainage from the bogs into the reservoir, the government have recently paid for these ditches to be blocked up again. I find it highly amusing and ironic to know that the government paid farmers to dig the ditches, and then paid the next generation of farmers to block them up again!

Bog restoration

The importance of bogs is now being recognised (1) for their rare biodiversity (2) their water storing ability which reduces the flooding risk and (3) their carbon sequestration capabilities. Due to this, The Chat Moss project has got funding to restore the mosses in outer Manchester towards their natural state.  

To achieve this they must: 

• Relevel large areas where peat extraction occurred. This should help allow the surface water to spread evenly over the top layer and let Sphagnum grow throughout.
• Block ditches to raise the water table and allow surface water levels to increase.
• Clear scrub to allow the Sphagnum to spread across the entire area. This scrub must then be removed completely from the area so that its decay doesn't change the nutrient content of the area.
• Remove invasive species to allow the native flora to recolonise without unnecessary competition.
• Translocate Sphagnum and other important flora for the habitat. By sourcing these from other bog areas locally, it is hoped that the species present, and the community as a whole, will eventually establish to something very similar to what was there originally.

The future of the Chat Mosses is looking promising at the moment as peat extraction licenses aren't being renewed, and funding has been secured to restore large areas and decrease habitat fragmentation. However, the long term future of the area is highly uncertain as funding is always difficult to maintain, and the Manchester population is ever expanding!

I personally found this talk very interesting! There were some parallels with the blanket bog at Vyrnwy, but I was amazed to find that there were so many differences between raised and lowland bogs (mainly due to the lack of nearby human habitation around raised bogs). Lowland bogs also sequester carbon faster than raised bogs and are therefore, currently, a far more valuable habitat to maintain, restore and expand. I hope that the Chat Moss project is successful in the long term, and that scientific and governmental policy makers are intelligent enough to recognise the potential benefits of such a habitat and protect it.