What is a wetland?
Canada’s wetlands are diverse. They take the form of marshes, bogs, fens, swamps and open water. They appear on the prairies, in the boreal forest, along coastlines and even in the tundra. Every type helps to keep our communities healthy and safe.
Wetlands are defined as land that is saturated with water long enough to promote wetland or aquatic processes as indicated by poorly drained soils, vegetation and other biological activity adapted to a wet environment. (National Wetlands Working Group 1997).
Wetland ecosystems provide ample food sources for a range of plants, insects, microbes, waterfowl and wildlife.
They protect us from flooding, drought and climate change. They protect wildlife by providing hundreds of species with safe places to eat, sleep and raise young. They give us natural places to play, learn and explore. They also clean the water we enjoy at beaches, lakes and rivers.
Types of wetlands
Canada’s wetlands can be broadly categorized into two types: organic and mineral.
Organic wetlands
Organic wetlands are Otherwise known as peatlands, these wetlands have an abundance of peat accumulation on which organic soils (excluding Folisols) are developed. These types of wetlands can include swamps, marshes, or shallow open-water wetlands.

Swamps
Most commonly recognized as shoreline areas of streams, lakes and floodplains, swamps are either treed or shrubby.



Marshes
Marshes are wetlands periodically inundated by standing or slowly moving water and creating nutrient-rich soil.


Shallow open-water wetlands
Shallow open-water wetlands have water depths of less than two metres, yet are too deep for emergent marsh vegetation to establish.
Mineral wetlands
Mineral wetlands are found in locations where there is an excess of water on the surface and where there is little or no organic matter or peat due to geomorphic, hydrologic, biotic, edaphic (soil-related), or climatic causes. These wetlands are distinguished by gleysolic soils or peaty phases of these soils.


Bogs
Bogs are peatlands that have deep deposits of poorly decomposed organic material (referred to as peat). They are elevated above the surrounding terrain and receive water and most nutrients from precipitation.


Fens
Fens are peatlands with deep organic deposits and are influenced by slow, lateral water movement. Often referred to as “muskeg,” fens are the most extensive wetlands in the western boreal forest.



Swamps
Most commonly recognized as shoreline areas of streams, lakes and floodplains, swamps are either treed or shrubby.



Marshes
Marshes are wetlands periodically inundated by standing or slowly moving water and creating nutrient-rich soil.
How wetlands work
Wetlands act like sponges, soaking up rain and melted snow, and can slowly release water during drier seasons.
They are a natural filter, slowing the flow of water, where aquatic vegetation and bacteria can break down contaminants, and store nitrogen instead of releasing it into the atmosphere as carbon dioxide.
Wetlands are often highly connected aquatic systems moving water and nutrients over long distances, making them vulnerable to developments that block their natural flow.


What we do
We are building on the momentum of our successes—working with our supporters to protect and restore Canada’s wetlands.
Estimates put 25 per cent of the world’s remaining marshes, bogs, swamps and other cattail-lined, carbon-rich water bodies inside Canada’s borders. Our understanding of wetlands is growing, but they continue to be lost. In southern areas of Canada, up to 70 per cent of our wetlands have already been destroyed or degraded and up to 95 per cent in densely populated areas. As they continue to disappear, so too do the many benefits they provide.
Putting wetlands on the map: Since 1979, DUC has used aerial photography and satellite imagery to map and inventory millions of acres of wetlands across Canada. In 2002, we started advocating for a national wetland inventory and monitoring system and, with the support of 150-plus conservation partners, have built a database — the Canadian Wetland Inventory.


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