Wetland classification


There is no commonly accepted definition of what constitutes a wetland. 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.

Ramsar classification

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.
The wetlands are classified into three major classes:
  • Marine/coastal wetlands
  • Inland wetlands
  • Human-made wetlands
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.

National systems of classification

Australia

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.
The following list is that used within Australia to classify wetland by type:A—Marine and Coastal Zone wetlands
  1. Marine waters—permanent shallow waters less than six metres deep at low tide; includes sea bays, straits
  2. Subtidal aquatic beds; includes kelp beds, seagrasses, tropical marine meadows
  3. Coral reefs
  4. Rocky marine shores; includes rocky offshore islands, sea cliffs
  5. Sand, shingle or pebble beaches; includes sand bars, spits, sandy islets
  6. Intertidal mud, sand or salt flats
  7. Intertidal marshes; includes saltmarshes, salt meadows, saltings, raised salt marshes, tidal brackish and freshwater marshes
  8. Intertidal forested wetlands; includes mangrove swamps, nipa swamps, tidal freshwater swamp forests
  9. Brackish to saline lagoons and marshes with one or more relatively narrow connections with the sea
  10. Freshwater lagoons and marshes in the coastal zone
  11. Non-tidal freshwater forested wetlandsB—Inland wetlands
  12. Permanent rivers and streams; includes waterfalls
  13. Seasonal and irregular rivers and streams
  14. Inland deltas
  15. Riverine floodplains; includes river flats, flooded river basins, seasonally flooded grassland, savanna and palm savanna
  16. Permanent freshwater lakes ; includes large oxbow lakes
  17. Seasonal/intermittent freshwater lakes, floodplain lakes
  18. Permanent saline/brackish lakes
  19. Seasonal/intermittent saline lakes
  20. Permanent freshwater ponds, marshes and swamps on inorganic soils; with emergent vegetation waterlogged for at least most of the growing season
  21. Seasonal/intermittent freshwater ponds and marshes on inorganic soils; includes sloughs, potholes; seasonally flooded meadows, sedge marshes
  22. Lakeshore mudflats in freshwater lakes and ponds
  23. Permanent saline/brackish marshes
  24. Seasonal saline marshes
  25. Shrub swamps; shrub-dominated freshwater marsh, shrub carr, alder thicket on inorganic soils
  26. Freshwater swamp forest; seasonally flooded forest, wooded swamps; on inorganic soils
  27. Peatlands; forest, shrub or open bogs
  28. Alpine and tundra wetlands; includes alpine meadows, tundra pools, temporary waters from snow melt
  29. Freshwater springs, oases and rock pools
  30. Geothermal wetlands
  31. Inland, subterranean karst wetlandsC—Human-made wetlands
  32. Water storage areas; reservoirs, barrages, hydro-electric dams, impoundments
  33. Ponds, including farm ponds, stock ponds, small tanks
  34. Aquaculture ponds; fish ponds, shrimp ponds
  35. Salt exploitation; salt pans, salines
  36. Excavations; gravel pits, borrow pits, mining pools
  37. Wastewater treatment; sewage farms, settling ponds, oxidation basins
  38. Irrigated land and irrigation channels; rice fields, canals, ditches
  39. Seasonally flooded arable land, farm land

United States

Wetlands of the United States are classified according to the U.S. Fish and Wildlife Service's National Wetlands Inventory.
In the US, the best known classification systems are the Cowardin classification system and the hydrogeomorphic classification system.