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Appendix

The function and type of Wetlands

Wetlands are areas of land covered with shallow water or have water at, or near, the surface for all or part of the year. Generally, wetlands have wet soils that are low in oxygen, and plants that are adapted to flooding and the lack of oxygen around their roots. Special air chambers in wetland plant stems carry oxygen from above the water to their roots. However, only a few plant species have adapted to waterlogged soils and these plants are common to many wetlands.

Marsh: Wetland dominated by emergent plants.

Wet meadow: Grassland with waterlogged soil; often flooded for short periods but without standing water in the growing season.

Swamp: Wetland dominated by trees and shrubs.

Bottomland/Riverine: Usually located along floodplains of streams and rivers; may flood seasonally or be at the same level as the river watertable. Often located at bottom of steep slopes and fill with spring meltwater or seepage from the slope. Created by river scouring during floods or old river scars and oxbows.

Bog: Acidic wetland dominated by mosses that buildup overtime to produce peat. There is little exchange of water in a bog.

Fen: Peat accumulating wetland that has alkaline ground water inflow from mineral soils. Like bogs fens accumulate peat. However, groundwater flows into them from the mineral soils, creating an alkaline environment.

Muskeg: Frozen peatlands.

Ephemeral wetlands: Seasonal ponds that fill with spring meltwater or that fill after a rain but they are dry by mid -summer.

Wetlands hold water. Peak flows are lowered and water released slowly from the wetland extends the flow period. Without wetlands there is a sudden peak flow and water drains away quickly.

Wetlands are important for several reasons. They represent only a part of our land base but they shelter a great number of species. Many species only use the wetland for a small but important part of their life cycle, to breed and reproduce. Wetlands moderate water flow by absorbing much of the surface water runoff from the land, and then by slowly releasing it. Thus, wetlands help to reduce flooding and to sustain water flow during dry spells. Wetlands also play an important role in water quality by trapping sediments, and absorbing excess nutrients and heavy metals.

Adjacent land-use is an important consideration in wetland conservation. Wetlands that are connected to upland terrestrial or forested sites add value to the landscape. For this reason, "buffers" around wetlands should extend into and include nearby habitats or upstream terrestrial environments.

Wetlands receive water from surface run off and water "leakage" recharges ground water.	Wetlands discharge water to the watershed and recharge underground aquifers.

Wetlands discharge water to the watershed and recharge underground aquifers. In some watersheds, wetlands may be interdependent. One wetland may depend on groundwater or discharge water flowing from another wetland. Thus, the loss of each wetland may have unanticipated impacts elsewhere in the watershed. We cannot expect our backyard wetland to replace these intricate relationships, nor that a wetland constructed to replace a drained site will have the same hydrological or wild life function.

Toads expand their range one wetland at a time.

On a community wide basis constructed wetlands can be very important. They can reduce peak flows to streams and maintain water levels during dry periods. Wetlands add a diversity of species to our communities by providing refuges for wetland wild life and by linking existing wetlands as stepping stones for wildlife. For example, toads can expand their range one wetland at a time and in this way reach new uncolonized wetlands and your backyard.