What causes bare peat?
During the 1800s the Industrial Revolution led to a massive increase in the number of factories in northern around the Peak District National Park.
Nitrous and sulphurous oxides released in the smoke from chimneys in South and West Yorkshire and Greater Manchester were deposited on the moors.
- Sulphurous oxides killed off sphagnum moss - the main peat-building material - this continued until the introduction of the clean air act in 1956.
- Nitrous oxide emissions (from vehicle exhausts and agricultural practices) still remain today. It doesn’t kill off sphagnum but the nutrient enrichment that occurs benefits grass so that they out-compete the mosses.
Access to moorland
It is estimated that 6 million people visit the Peak District moors each year and the trampling of vegetation and loss of peat has both impacts on the landscape character and wildlife.
Much of the heather moorland we see today has been shaped by the process of burning small areas of heather on a rotational basis in the winter months to favour grouse. Experts from Natural England are currently reviewing the impacts of these practices in their Upland Evidence Review.
However it is the impact of summer wildfires caused deliberately (e.g. arson) or by carelessness (e.g. discarding cigarettes) that seriously threatens the fragile moorland habitats of the Peak District, as large areas can be destroyed very quickly.
Wildfires occur during the drier months when the water table is lower. The peat is drier and more flammable, making the moors very combustible. These fires can extend for several miles, burn deep into the peat, and sterilise the soil.
In addition, early summer fires can have a disastrous effect on wildlife when birds are nesting and sheep lambing. Moorland fires pose a huge financial burden because they are inaccessible. Specialised equipment including helicopters is often used to supply the water needed to control the fires.
Between 1976 and 2006 there were 365 reported summer wild moorland fires in the Peak District.
Find out about the Peak District Fire Operations Group
Bare eroded peat is more vulnerable to damage caused by weather conditions. With little or no vegetation to ‘knit’ the soil together the water table lowers and the peat dries out. the higher moors of the Peak District and South Pennines are regularly subjected to frost heave, with repeated daily cycles of freezing and thawing lifting the surface layers of peat from the main peat body.
In turn, this results in the soil being blown away by the wind and washed away by the rain during the following summer and is why 2.5cm depth of peat a year is lost over all of the areas of bare peat.
After the Second World War there was a drive to increase agricultural production and land that was previously deemed unproductive, including moorland, was drained and turned to pasture.
This policy is no longer promoted and gully blocking has been initiated to re-wet moorland areas, through the use of dams.
Competition by non-native plants
Species such as Rhododendron, which are not native to the moorlands, have been introduced for differing reasons over the years. These species have few predators and can spread and out-compete native species.
There were an estimated 116,000 sheep grazing the Peak District moors in 1994.
With so many mouths to feed the moors were almost stripped bare of the lush moorland vegetation and in its place more vigorous and less edible species such as wavy hair grass began to dominate.
Through the use of agri-environment scheme subsidies these stocking rates have been dramatically reduced.