A wetland is a land area that is saturated with water, either permanently or seasonally, such that it takes on characteristics that distinguish it as a distinct ecosystem.[2] The primary factor that distinguishes wetlands is the characteristic vegetation that is adapted to its unique soil conditions: Wetlands are made up primarily of hydric soil, which supports aquatic plants.[3][4]
The water found in wetlands can be saltwater, freshwater, or brackish.[4] Subsets of wetlands include swamps, marshes, and bogs, among others.[5]
Wetlands play a number of roles in the environment, principally water purification, flood control, and shoreline stability. Wetlands are also considered the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal life.[6]
Wetlands occur naturally on every continent except Antarctica.[5] They can also be constructed artificially as a water management tool, which may play a role in the developing field of Water Sensitive Urban Design.
