Wetlands are areas that are either permanently or seasonally wet, and the soil and the plant community has adapted to that water. Many types of wetlands exist, each with a community of plants adapted to specific conditions that are determined by the hydrology (the source, quantity, and quality of the water supply), and the underlying soil chemistry.
Some wetlands, such as fens or sedge meadows, may be fed by subsurface or surfacing groundwater. Others, such as a floodplain forest, are periodically flooded by overflowing rivers or streams. Still others, such as bogs or vernal pools, capture rainwater in depressions or basins on the land. Marshes are areas with plants that normally grow in relatively shallow water, while a swamp is much like a marsh that is forested.
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