Chapter 1.0
Introduction
Background about wetlands and a summary of contents in this report
Wetland ecosystems cover more than 20 percent of Alberta and are a critical element of Alberta's diverse landscape.
- Wetlands are defined by their hydrology (periodic saturation or standing water); their physicochemical environment (e.g., anaerobic soil, chemistry); and their biota (aquatic plants, animals, and microbes).
- These components interact in a multitude of ways, creating biodiverse habitats for a wide variety of flora and fauna, and providing multiple ecosystem functions that benefit humans.
- Impacts to wetlands from humans take a variety of forms and can be direct or initiated elsewhere in the catchment area. Therefore, a watershed-scale approach is necessary for wetland management and protection.
Richard Bukowski
Introduction
"Wetlands are land saturated with water long enough to promote formation of water-altered soils, growth of water-tolerant vegetation, and various kinds of biological activity that are adapted to a wet environment"[1].
- Three elements (hydrology, physicochemical environment including soil, and biota) are used to identify a wetland and describe the main components of wetland ecosystems.
- These interconnected components form a complicated web of two-sided relationships. For example, biota like Beavers and Sphagnum moss create conditions that suit themselves, thereby affecting the hydrology of the whole system.
- Environmental context (e.g., geology, climate) drives wetland hydrology and, therefore, the other components of wetlands (e.g., vegetation has a tolerance for wet conditions and only specific species will grow under different conditions).
- The range of the primary components of wetlands—hydrology, physicochemical environment, and biota—are grouped to define different wetland classes, types, and forms.
Wetland ecosystems are areas of periodic saturation or flooding, with wet-adapted biota and unique physicochemical components, which form from climate and surrounding geomorphology.
Types of Wetlands in Alberta
In Alberta, the wide variety of wetlands is described by the Alberta Wetland Classification System[2].
Wetlands are most broadly broken into classes. Each wetland class can be broken into wetland form, based on vegetation structure, and further into types, based on water permanence and chemistry. More information can be found in Ducks Unlimited Canada’s Alberta Wetland Classification System Field Guide[2].
There are five wetland classes in Alberta:
Bog
- Peatland (has organic soil or peat, partially decomposed plant material)
- Water source is primarily from precipitation (no groundwater); water levels are usually fairly stable and sit below the ground surface
- Can have treed, shrubby, or open vegetation structure
- Conditions are acidic and nutrient poor
Fen
- Peatland (has organic soil or peat, partially decomposed plant material)
- Varied water sources (precipitation, groundwater, and/or surface water); water levels are usually consistently at the surface; water flows slowly
- Can have treed, shrubby, or graminoid vegetation structure
Swamp
- Swamps can be mineral wetlands or peatlands, but if they have organic soil, it is typically more decomposed than in fens or bogs
- Varied water sources (precipitation, groundwater, and/or surface water); water levels fluctuate near the surface
- Can have treed or shrubby vegetation structure
Marsh
- Mineral soils
- Varied water sources (precipitation, groundwater and/or surface water); fluctuating water levels
- Graminoid vegetation structure
Shallow Open Water
- Mineral soils
- Varied water sources (precipitation, groundwater, and/or surface water); fluctuating water levels up to 2 m deep
- Submersed and/or floating aquatic vegetation structure
Wetland Ecosystem Services
Wetlands are transitional habitats that have characteristics of both upland and aquatic environments.
These conditions create diverse habitats that support a wide variety of flora and fauna, such as: aquatic invertebrates, amphibians, mosses, vascular plants and birds.
Wetland ecosystems provide a number of important benefits. For example:
- As the “kidneys of the landscape”, wetlands filter and improve water quality.
- They stabilize water supplies and reduce the negative effects of floods and droughts.
- Wetlands sequester and store atmospheric carbon.
- They provide essential habitat for a variety of wildlife and plant species.
- Wetlands also provide a range of recreational and educational opportunities, such as boating, bird watching and photography, and opportunities for aesthetic appreciation.