Terrestrial wetlands

Abstract

Terrestrial wetlands are specialized plant communities that occur where soil remains saturated for most of the year. The natural diversity of wetland communities reflects the different conditions in which they form. The cool, moist climate at higher latitudes favours the extensive development of bogs and fens, but in temperate and tropical regions swamps and marshes are more widespread. Bogs and fens are mainly distinguished on the basis of the origin and chemistry of the water that moves through them. Bogs are fed only by the precipitation that falls directly on them and the supply of nutrients is therefore very limited. The peat which accumulates beneath bogs is mainly derived from Sphagnum and woody ericaceous shrubs that are well adapted to the acid conditions. Fens are mostly supplied by water from the surrounding area which has picked up nutrients in its movement through the adjacent mineral soils. Sedges and grasses grow abundantly in these minerotrophic conditions.