Mosslands was originally the local name for what ecologist's call 'lowland raised bog', although today the term 'mosslands' is also used to cover the areas that were formerly bogs, but which have now been converted to farmland.
Lowland raised bogs are areas of deep peat, which have developed over thousands of years in lowland areas where drainage has been poor. Poor drainage leads to the area becoming water-logged. Peat is then formed because the lack of oxygen slows down the decomposition of plant materials. Instead of rotting, the dead plant materials build up as peat. This process lifts the surface above the surrounding area to create a distinctive dome shape - the "raised bog".
Undamaged raised bogs support a range of bog mosses (sphagnum), together with cotton grasses, cross-leaved heath, bog rosemary and sundews. They also support a range of invertebrates. Over the last few hundred years most of this habitat has been lost through development farming and peat extraction. The government nature conservation advisors have estimated that the extent of remaining undamaged raised bog has declined in the UK by 94%, from 95,000 hectares at the beginning of the nineteenth century, down to approximately 6,000 hectares in the mid 1990s.
Locally it has been estimated that there were originally some 2,650 hectares of lowland raised bog covering the overall area now known as Chat Moss (which lies in the south west of Salford and extends into Wigan). However, by the 1990s around 1,900 hectares of this had been drained and fertilised to create agricultural land. 310 hectares of relatively undamaged peat deposits remained in four peat extraction sites mostly in Salford. Additionally, some land in Wigan retained some remnants of previous mosslands vegetation such as cotton grass. All the 93 hectares of remnant bog vegetation and 42 hectares of peat extraction sites lie within Wigan, and 268 hectares of the peat extraction sites lie in Salford.
Given the extent of loss of the original bog habitat, and the commitments in recent legislation to the need to take account of biodiversity, there is an increased level of importance being attached to both bog remnants and opportunities to restore this habitat in an area where it was previously, a key feature of the landscape. This has led to the designation of the 93 hectares of remnant bog in Wigan as part of the Manchester Mosses, special area of conservation (which means that it is considered to be of European importance).
It is thought that because of the relatively undamaged condition of the peat deposits within the extraction sites, they represent the best opportunities to restore areas of bog habitat in Salford. Peat extraction has now ceased on two of the peat extraction sites in Salford. The city council is working with landowners and the peat extractors on both current and former peat extraction sites in order to seek successful restoration to bog habitats.
UK BAP provides further information on lowland raised bog as a UK 'priority habitat'.