Peat

Peat is a soil consisting of semi-decomposed plant material which accumulates in situ as a result of waterlogging. The percentage of mineral matter contained within such soils can vary from as little as 2% by weight to as much as 30%, though even this upper limit is more an agreed convention than any strict biological threshold. Peat can be generated from a wide range of plant materials under various forms of waterlogging. The orderly nature of peat layers, which may attain depths of 40 m or more and which may have accumulated over periods as long as 100,000 years, offer much of interest to palaeobotanists and archaeologists, particularly as the processes which result in the preservation of plant material also preserve other objects, such as human remains. The carbon stored in the world's peatlands exceeds that which is stored in all the world's vegetation.