The process of forming peat moss, which takes place over centuries, consists in the accumulation and fossilization of vegetation debris in wetlands called peatlands. In Canada, these wetlands developed following the retreat of the last glaciers and are now between 5,000 and 10,000 years old.
Steps in peatland formation
The physical and chemical composition of peat depends on several factors such as the type of vegetation, the climate, the acidity of the water and the extent of diagenesis. Peat is comprised mostly of water and ash (80% to 90%) and of decomposed organic matter. Nature needs about a century to make peat moss five centimetres thick. Sphagnum growth rates can reach 2 to 12 centimetres per year, depending on peatland characteristics. However, since plant residues are decomposed and compacted as they accumulate, peat accumulation is limited to about 0.5 to 1 mm per year.
In its natural state, peat is a light, spongy and fibrous substance whose colour varies from pale to dark brown and even to black according to its age and carbon content.
The younger the peat, the paler its shade and the lower its carbon content. Conversely, peat becomes darker as it ages, and its carbon content rises up to 60%. This is the reason it has been used as fuel for centuries in some countries, notably in Scotland and Ireland.
Pale blond peat
Diagenesis - The processes that transform sediment into solid rock.
Von Post Scale(H1 à H10) : Degree of decomposition: The closer peat approaches H10, the more decomposed it is.