Classification of wetlands has been a problematical task, with the commonly accepted definition of what constitutes a wetland being among the major difficulties. A number of national wetland classifications exist. In the 1970s, the Ramsar Convention on Wetlands of International Importance introduced a first attempt to establish an internationally acceptable wetland classification scheme. [1]
The Ramsar classification of wetland types is intended as a means for fast identification of the main types of wetlands for the purposes of the convention. [2]
The wetlands are classified into three major classes:
These are further subdivided by the type of water: fresh / saline / brackish / alkaline; and may be further classified by the substrate type of other characteristics.
Wetlands in Australia that considered to be of national importance are so classified by criteria published in association with the Directory of Important Wetlands in Australia (DIWA). [3]
The following list is that used within Australia to classify wetland by type: [4]
Wetlands of the United States are classified according to the U.S. Fish and Wildlife Service's National Wetlands Inventory (NWI). [5]
In the US, the best known classification systems are the Cowardin classification system and the hydrogeomorphic (HGM) classification system.
A swamp is a forested wetland. Swamps are considered to be transition zones because both land and water play a role in creating this environment. Swamps vary in size and are located all around the world. The water of a swamp may be fresh water, brackish water, or seawater. Freshwater swamps form along large rivers or lakes where they are critically dependent upon rainwater and seasonal flooding to maintain natural water level fluctuations. Saltwater swamps are found along tropical and subtropical coastlines. Some swamps have hammocks, or dry-land protrusions, covered by aquatic vegetation, or vegetation that tolerates periodic inundation or soil saturation. The two main types of swamp are "true" or swamp forests and "transitional" or shrub swamps. In the boreal regions of Canada, the word swamp is colloquially used for what is more formally termed a bog, fen, or muskeg. Some of the world's largest swamps are found along major rivers such as the Amazon, the Mississippi, and the Congo.
Wetlands, or simply a wetland, is a distinct ecosystem that is flooded or saturated by water, either permanently or seasonally. Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The primary factor that distinguishes wetlands from terrestrial land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique anoxic hydric soils. Wetlands are considered among the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal species. Methods for assessing wetland functions, wetland ecological health, and general wetland condition have been developed for many regions of the world. These methods have contributed to wetland conservation partly by raising public awareness of the functions some wetlands provide. Constructed wetlands are designed and built to treat municipal and industrial wastewater as well as to divert stormwater runoff. Constructed wetlands may also play a role in water-sensitive urban design.
A marsh is — according to ecological definitions — a wetland that is dominated by herbaceous rather than woody plant species. More in general, the word can be used for any low-lying and seasonally waterlogged terrain. In Europe and in agricultural literature low-lying meadows that require draining and embanked polderlands are also referred to as marshes or marshland.
Flooded grasslands and savannas is a terrestrial biome of the World Wide Fund for Nature (WWF) biogeographical system, consisting of large expanses or complexes of flooded grasslands. These areas support numerous plants and animals adapted to the unique hydrologic regimes and soil conditions. Large congregations of migratory and resident waterbirds may be found in these regions. The relative importance of these habitat types for these birds as well as more vagile taxa typically varies as the availability of water and productivity annually and seasonally shifts among complexes of smaller and larger wetlands throughout a region.
A Ramsar site is a wetland site designated to be of international importance under the Ramsar Convention, also known as "The Convention on Wetlands", an international environmental treaty signed on 2 February 1971 in Ramsar, Iran, under the auspices of UNESCO. It came into force on 21 December 1975, when it was ratified by a sufficient number of nations. It provides for national action and international cooperation regarding the conservation of wetlands, and wise sustainable use of their resources. Ramsar identifies wetlands of international importance, especially those providing waterfowl habitat.
A tidal marsh is a marsh found along rivers, coasts and estuaries which floods and drains by the tidal movement of the adjacent estuary, sea or ocean. Tidal marshes experience many overlapping persistent cycles, including diurnal and semi-diurnal tides, day-night temperature fluctuations, spring-neap tides, seasonal vegetation growth and decay, upland runoff, decadal climate variations, and centennial to millennial trends in sea level and climate.
An aquatic ecosystem is an ecosystem found in and around a body of water, in contrast to land-based terrestrial ecosystems. Aquatic ecosystems contain communities of organisms—aquatic life—that are dependent on each other and on their environment. The two main types of aquatic ecosystems are marine ecosystems and freshwater ecosystems. Freshwater ecosystems may be lentic ; lotic ; and wetlands.
Spittal Pond Nature Reserve is the largest wildlife sanctuary in Bermuda, located close to the Atlantic coast of Smith's Parish. Surrounding the third largest pond in Bermuda, Spittal Pond, it covers an area of 60 acres (24 ha). It is one of 13 parks or reserves managed by the Bermuda Department of Conservation Services which protects and conserves environmentally critical areas and habitats. The pond reserve, a wetland site, is one of the seven Ramsar Sites in Bermuda, which was approved on 10 May 1999 for the criteria of its unique characteristics such as its lagoon which is permanently brackish, ecology featuring wet grassland and mangrove forests, seasonal shorebirds, other ver run waterbirds and European eels. It is also home to many types of species mostly including birds.
The Congo clawless otter, also known as the Cameroon clawless otter, is a species in the family Mustelidae. It was formerly recognised as a subspecies of the African clawless otter.
Reedy Lake, historically also known as Lake Reedy, is a shallow 5.5-square-kilometre (2.1 sq mi) intermittent freshwater lake or swamp on the lower reaches of the Barwon River, on the Bellarine Peninsula southeast of Geelong in the Australian state of Victoria.
The Edithvale-Seaford Wetlands is a collection of principally freshwater swamps and marshlands totalling 261 hectares in southeastern Melbourne, Victoria, Australia, about 30 km (19 mi) southeast of Melbourne CBD. It is the largest natural wetland of its type in the Port Phillip and Western Port basins, and is all that remains of the historic Carrum Carrum Swamp, which once covered more than 4,000 hectares from present-day Mordialloc in the north to Frankston in the south.
Mandora Marsh, also known as Mandora Salt Marsh, is a complex and diverse wetland system in Western Australia close to Eighty Mile Beach, and included in the Eighty Mile Beach Ramsar Site. It lies at the western edge of the Great Sandy Desert bioregion and within the Mandora Station pastoral lease. The marsh is part of the 3337 km2 Mandora Marsh and Anna Plains Important Bird Area, identified as such by BirdLife International because of its importance for supporting large numbers of waders and waterbirds.
Toolibin Lake is a seasonal fresh to brackish water perched lake or wooded swamp, in south-western Australia. The lake is contained with a 493-hectare (1,218-acre) nature reserve and it is located about 200 kilometres (124 mi) south-east of Perth, in the Shire of Narrogin, and 40 kilometres (25 mi) east of the town of Narrogin, in the Wheatbelt region of Western Australia. The lake is listed by the Australian Government as a threatened ecological community under the Environment Protection and Biodiversity Conservation Act 1999.
The Hunter Estuary Wetlands comprise a group of associated wetlands at and near the mouth of the Hunter River in the city of Newcastle, New South Wales, Australia. The wetlands are part of Hunter Wetlands National Park. 30 km2 of the wetlands have been recognised as being of international importance by designation under the Ramsar Convention. It was listed on 21 February 1984 as Ramsar site 287. A larger area of the wetlands has been identified by BirdLife International as an Important Bird Area (IBA). The wetlands are recognised as the most important area in New South Wales for waders, or shorebirds.
Sarstoon-Temash is the southernmost national park in Belize. The national park was designated in 1994, and covers an area of 165.92 km2. It is managed by the Sarstoon Temash Institute for Indigenous Management (SATIIM), in partnership with the Forest Department.
Mediterranean Wetlands comprise the wetlands of the Mediterranean region.
The Bohai Sea saline meadow ecoregion covers the coastal deltas of the Yellow River and the Luan River where they enter the Bohai Sea in China. The saline meadows and intertidal mudflats provide an important stopping-over point for birds migrating on the East Asian–Australasian Flyway. The region is under heavy ecological pressure from human development.
The Nenjiang River grassland ecoregion covers the low wetlands of the lower Nen River in northeast China. The region is known for supporting migratory and permanent nesting populations of a variety of migratory waterfowl, including six species of crane.
The Tonle Sap-Mekong peat swamp forests ecoregion covers a patchwork of areas permanently inundated with fresh water along the Tonle Sap River and Mekong River floodplains in Cambodia and Vietnam. The terrain is mostly flat, with extensive agricultural fields, reed beds, and degraded shrub forest. Less than 10% of the region is in its original state, and less than 1% is protected. Habitat in the region is distinguished from the Tonle Sap freshwater swamp forests ecoregion that runs through the middle, as that ecoregion is only seasonally flooded.
Lake Muir Nature Reserve is a protected area in Western Australia. It encompasses Lake Muir and several smaller lakes and wetlands. It is an important refuge for water birds, and home to several rare plants and plant communities.