Description:
Wetlands are widely distributed in the Arctic, covering about 70% of the region. Of the six Ramsar wetland types represented, the most extensive are forested and non-forested peatlands. Peatlands are wetlands where organic matter (peat) derived from dead and decaying plant material has accumulated and remains stored under conditions of permanent water saturation. Those which still have peat-forming vegetation are known as mires, and can be divided into fens (minerotrophic) and bogs (ombrotrophic) on the basis of nutrient status, which is closely related to the quality of the water supply. Freeze-thaw processes play a key role in the development and maintenance of these peatlands by shaping the surface of the landscape, and the types that are exclusive to the Arctic – most notably polygon mires and palsa mires – are associated with permafrost.