A wetland is an area of ground that is saturated with water either permanently or seasonally. Wetlands are categorized by their characteristic vegetation, which is adapted to these unique soil conditions. The water found in wetlands can be saltwater, freshwater, or brackish. Wetlands include swamps, marshes, and bogs, among others.
Wetlands are found on every continent except Antarctica. One of the world's largest natural wetlands is the Pantanal, which straddles Brazil, Bolivia, and Paraguay in South America. The main functions of wetlands are as water purification systems, flood control, shoreline stability, and as reservoirs of biodiversity. Wetlands may be converted for agriculture or development or constructed as a water management tool as in the recent developing field of Water Sensitive Urban Design.
The study of wetlands has recently been termed paludology in some publications. Wetlands also are known internationally as inland water or coastal/marine ecosystems.
The UN Millennium Ecosystem Assessment determined that environmental degradation is more prominent within wetland systems than any other ecosystem on Earth. International conservation efforts and the development of rapid assessment tools are being used in conjunction with each other to inform people about wetland issues.
