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According to the EPA, a wetland is an area where water covers the soil, or is present either at or near the surface of the soil for significant portions of the year, including during the growing season. Wetlands act as the transition between the land and the water. The hydrology of the site or the amount that the water is saturated plays an integral part in the composition of the soil and on the aquatic life that lives there. Wetlands are unique ecosystems as they support both terrestrial and aquatic life. The prolonged presence of water creates conditions that favor the growth of specially adapted plants (hydrophytes) and promote the development of characteristic wetland (hydric) soils. !aerial2LG.jpg!Source: USGS
Wetland soils are saturated long enough in the growing season to create an anaerobic (low oxygen) state in the soil horizon (the layers of soil found as you dig a hole) The wetlands soil becomes so saturated with water that it cannot hold much, if any, oxygen.
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