Defining ecozones How is an ecozone determined? What were the key diagnostic characteristics for each Canadian ecozone? Were the same characteristics used for each? Which characteristics are essential and which are incidental? In part, the answer to these questions is based on what common sense would suggest.
In any large ecosystem -- the forested mountains of the west coast, the arctic lowlands of the Northwest Territories, the great plains of the prairie provinces -- the particular combinations of characteristics like climate, landforms, soils, plants, animals, and human activities are distinctive.
These combinations remain relatively constant for each ecosystem. Ecozones still have to be judged on a case-by-case basis. Characteristically, they are large units i. Most of the diagnostic features are factors normally thought of as natural -- landforms, soils, water features, vegetation, climate. However, where human activities are extensive and are key to sustaining the character of the area, they are also diagnostic.
Agricultural activity is a fairly diagnostic feature of the Prairies Ecozone; the occurrence of certain types of soils, the plains physiography, the former extent of native grasslands, and other features would also be considered in determining the boundary and traits of this particular zone.
The legend on the map arranges the ecozones according to general shared properties. For instance, all of the marine units are grouped, as are the boreal and arctic units. Ecozones vary in shape and size. The largest in Canada -- the Boreal Shield Ecozone -- is an irregularly shaped area stretching across parts of six provinces. It is bigger than the state of Alaska, the country of Mongolia, and the province of Quebec.
Canada's three arctic ecozones, which occupy diagonal bands across the North, collectively cover an area more than four times the size of France. The main wetland-dominated ecozone -- the Hudson Plains -- is larger than Italy and is the world's largest wetland area. Ecozones vary in diversity as well. The Pacific Maritime unit is a lot like a layer cake. Temperate rain forest dominates much of the lower and mid elevations, but the base includes areas such as semi-Mediterranean arbutus and Garry Oak woodlands while, several layers higher up, alpine meadows and snow packs dominate.
Ecozones also differ with respect to their opportunities and constraints for particular activities and uses, such as agriculture, forestry, fishing, and recreation. For instance, although agriculture is successful in many areas across the country, it is predominantly associated with the Prairies and Mixedwoods Plains ecozones. Some of Canada's ecozones are shared with other countries. This ecozone also forms part of the world's set of temperate grasslands. Environment Canada.
The state of Canada's environment Ecological Stratification Working Group. A national ecological framework for Canada. Wiken, E. Terrestrial Ecozones of Canada. Ecological Land Classification, Series No. Hull, Quebec. Ecosystems: frameworks for thought. Volume 27, Number 1. Over the past few hundred years, this ecozone has been changed from forests, wetlands, prairies and alvars to a landscape dominated by agriculture and settlement.
The Carolinian zone the most southerly portion of this ecozone has many species that are not found in the rest of Canada. Parts of four of these lakes lie in Ontario and are shared with the United States; the exception is Lake Michigan, which is wholly contained within the United States. Shaped by glaciers more than 10, years ago, each of the Great Lakes reflects that history differently, with coastal areas that are variously composed of bedrock, cobble beaches, sand dunes or alvars.
The Ontario portion of the Great Lakes represents 8 per cent of the province. The Great Lakes Ecozone is one of the most ecologically diverse regions in North America, but the biodiversity of the area has been adversely affected by its high population and associated industries. Back to Top. You never know, if coming to UK, will get you another degree at much cheaper cost. You get a chance to enjoy the British life and culture. Length and Types. Table of Contents.
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