Mixedwood Plains Ecozone (Canada)

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Mixedwood Plains
Kelso Conservation Area- Escarpment - Milton Heights-Ontario (2).jpg
A representative stand of deciduous forest typical of this ecoregion
Mixedwood Plains Ecozone (Environment Canada) 2012.png
Ecology
Borders
Geography
Area168,204 km2 (64,944 sq mi)
Country Canada
Provinces
Climate type Humid continental (hot summer in some areas)

The Mixedwood Plains Ecozone is the Canadian ecozone with the most southern extent, covering all of southwestern Ontario, and parts of central and northeastern Ontario and southern Quebec along the Saint Lawrence River. It was originally dominated by temperate deciduous forest growing mostly on limestone covered by glacial till. It is the smallest ecozone in Canada, but it includes the country's most productive industrial and commercial region, [1] and is home to nearly half of Canada's population, including its two largest cities, Toronto, Ontario and Montreal, Quebec. [2] [3] Hence, little of the original forest cover remains, making protection of the remaining forests a high conservation priority. This ecozone includes two regions described by J.S. Rowe in his classic Forest Regions of Canada: the entire Deciduous Forest Region, and the southern portions of the Great Lakes-St. Lawrence Forest Region. [4] In the province of Ontario, the Ontario Ministry of Natural Resources maps this area as Site Regions 6E and 7E. [5]

Contents

The United States uses a different terminiology; the corresponding Level I ecoregion of the United States Environmental Protection Agency system is the Eastern Temperate Forest ecoregion. To deal with the differences in names between Canada and the United States, the Commission for Environmental Cooperation has produced a continental atlas. In this atlas, the Mixed Wood Plains is a Level II Ecoregion 8.1, which includes the above areas within Canada, as well as adjoining parts of the United States. [6]

Geography

The Mixedwood Plains stretch along the Quebec City-Windsor corridor. At its western end, it encompasses all of Southwestern Ontario, and is bounded by three Great Lakes and their connecting waterways. To its north is Lake Huron, and to the south Lake Erie. Further east, it has boundaries with Lake Ontario to the south and Lake Simcoe to the north, before continuing east along a narrow strip of the Saint Lawrence River coast toward Quebec. It covers approximately 9% of the total surface of Canada [7] and has a geographic area of 175,963 km2. [1]

Most of the ecozone is underlain by Paleozoic rock, mostly limestone, covered with various deposits of glacial till including moraines, drumlins and old glacial lake bottoms. The eastern areas were flooded by the Champlain Sea. One prominent rock feature is the Niagara Escarpment, which bifurcates the region from Niagara Falls to the northern tip of the Bruce Peninsula, then extends to Manitoulin Island. Another is the Frontenac Axis, an exposure of Canadian shield rocks that extends south to the St. Lawrence River near Kingston, creating the Thousand Islands. In south-central Ontario, the ecologically important and politically sensitive Oak Ridges Moraine is a major feature. [8]

The hooded warbler nests in the southern forests of the mixedwood plains ecozone. Wilsonia citrina (Belize).jpg
The hooded warbler nests in the southern forests of the mixedwood plains ecozone.

Owing to its southern location, it initially had a high natural biological diversity. For example, the Lake Erie Plains region has the highest tree diversity in Canada, with species such as tulip tree, cucumber tree, pawpaw, black gum, sassafrass and black oak. [9] American chestnut was common in this region before the arrival of chestnut blight, though it is now very rare. The area also has a high diversity of songbirds, reptiles and amphibians. [10]

Some of the most fertile soil in Canada is located in this ecozone, in which the Holland Marsh has come to be known as "Ontario's vegetable basket", and the Niagara Peninsula is the most productive wine region in the country.

This ecozone is subdivided into four ecoregions: St.Lawrence Lowlands 132, Frontenac Axis 133, Manitoulin-Lake Simcoe 134 and the Lake Erie Lowland 135. The Lake Erie Lowland corresponds roughly to Site Region 7E, [5] and to the more general term "Carolinian Forest." [10]

Ecoprovinces

This ecozone can be further subdivided into two ecoprovinces: [11]

Climate

The climate of the Mixedwood Plains is characterized by warm to hot summers and cool winters. The Great Lakes and Saint Lawrence River have a significant moderating effect in this ecozone, which is in a major North American storm belt. Warm air fronts from the Gulf of Mexico and US south- and mid-west often collide with cold polar air masses, providing abundant precipitation in some areas. [2] Annually, the region receives between 720 and 1,000 mm of precipitation. Most areas receive close to 150 cm of snowfall but snowbelt areas can receive well over 300 cm during a typical winter. [12]

Summers average about 23 °C in July in the southwestern end of the zone, to 18 °C in the higher part of the north. Winters are much milder in the southwest along the Lake Erie shore, with a mean January temperature of -3 °C, whereas mean lows are -12 °C in the northeast. Some lakeshore areas have over 200 frost-free days per year. [12]

Because of the relatively mild climate for Canada, the region has become an important and productive agricultural area. Agriculture has been the primary cause of deforestation in the ecozone; [2] it was once covered entirely by forests. The resultant loss of natural habitat has caused a decline in the populations of many native species, and now over half of the Species at Risk in Canada are found in this zone. [2]

Ecology

Forests

A representative stand of deciduous forest near Peterborough with white trilliums in flower. Forest-peterborough-Ontario.jpg
A representative stand of deciduous forest near Peterborough with white trilliums in flower.
The tulip tree grows in the southern forests of the mixedwood plains ecozone. Liriodendron tulipifera flower.jpg
The tulip tree grows in the southern forests of the mixedwood plains ecozone.

The forests are a part of the temperate deciduous forest that extends from Florida north to eastern Canada. [13] The mixed plains ecozone has the highest plant diversity in Canada, with the Lake Erie lowland having trees species that occur nowhere else in Canada. Within Canada, these forest types are often referred to as the 'Carolinian zone' owing to the many southern plants and animals that reach their northern limits here. Clearing for agriculture and urbanization have reduced natural forest cover to less than ten percent. An overview of the flora and fauna of this distinctive region is available in The Natural Treasures of Carolinian Canada. [10] A few of the many examples of southern species found here include the hooded warbler, king rail, prothonotary warbler, blue-gray gnatcatcher, American badger, opossum, and eastern spiny softshell turtle. Past work has identified 38 critical natural areas, and an initiative known as The Big Picture aims to restore natural corridors as part of a natural heritage system. Some of the critical core areas in this region include Point Pelee, Long Point, Rondeau Park, Skunk's Misery, Backus Woods and Willoughby Marsh.

Wetlands

Long Point extends into Lake Erie. It supports a rich flora and fauna typical of the Lake Erie Lowland. LongPointLakeErieOntario23.jpg
Long Point extends into Lake Erie. It supports a rich flora and fauna typical of the Lake Erie Lowland.

There is a rich diversity of wetlands in this ecozone owing to the presence of the Great Lakes and two major rivers, the Ottawa River and the St. Lawrence River. The wetlands on the Great Lakes are influenced by the slope of the shoreline, the type of substrate, exposure to waves, and the natural water level changes that characterize these lakes. [14] Some nationally significant wetlands include Point Pelee National Park and Long Point, both on Lake Erie, and Presqu'ile Provincial Park on Lake Ontario. The wetlands of the St. Lawrence and Ottawa River have a diverse array of vegetation types as well, although these have been damaged by the construction of power dams and locks for shipping. [15] Vast numbers of waterbirds use these wetlands during migration, and they provide important habitat for fish. [16]

Human population

The Mixedwood Plains is the most populated ecozone in Canada, with about half of the country's total population. [3] Of the top 25 most populous cities in Canada, 13 are found in this ecozone, including the two largest, Toronto with 6.1 million inhabitants and Montreal with 4.2 million inhabitants, as well as the country's capital city, Ottawa.

Conservation

Human settlement has had a major impact on this ecoregion. A majority of the forested land has been cleared for agriculture, and a majority of the wetlands have been drained or filled. Hence, the remaining forests and wetlands are important for conservation of wild species, and for the ecological services provided to humans by forests and wetlands.

Protected areas

A number of protected areas have been established to protect representative and/or significant portions of this ecozone. Those designated by the federal government include Bruce Peninsula National Park, Point Pelee National Park, and Thousand Islands National Park. Those designated by provincial governments include Presqu'ile Provincial Park. [17]

About 1.51% of the ecozone is protected, [18] the smallest percentage amongst the terrestrial ecozones in Canada.

Related Research Articles

<span class="mw-page-title-main">Geography of Canada</span>

Canada has a vast geography that occupies much of the continent of North America, sharing a land border with the contiguous United States to the south and the U.S. state of Alaska to the northwest. Canada stretches from the Atlantic Ocean in the east to the Pacific Ocean in the west; to the north lies the Arctic Ocean. Greenland is to the northeast with a shared border on Hans Island. To the southeast Canada shares a maritime boundary with France's overseas collectivity of Saint Pierre and Miquelon, the last vestige of New France. By total area, Canada is the second-largest country in the world, after Russia. By land area alone, however, Canada ranks fourth, the difference being due to it having the world's largest proportion of fresh water lakes. Of Canada's thirteen provinces and territories, only two are landlocked while the other eleven all directly border one of three oceans.

<span class="mw-page-title-main">Lake Ontario</span> Easternmost of Great Lakes in U.S. and Canada

Lake Ontario is one of the five Great Lakes of North America. It is bounded on the north, west, and southwest by the Canadian province of Ontario, and on the south and east by the U.S. state of New York. The Canada–United States border spans the centre of the lake.

<span class="mw-page-title-main">Point Pelee National Park</span> National park of Canada in Ontario

Point Pelee National Park is a national park in Essex County in southwestern Ontario, Canada where it extends into Lake Erie. The word pelée is French for 'bald'. Point Pelee consists of a peninsula of land, mainly of marsh and woodland habitats, that tapers to a sharp point as it extends into Lake Erie. Middle Island, also part of Point Pelee National Park, was acquired in 2000 and is just north of the Canada–United States border in Lake Erie. Point Pelee is the southernmost point of mainland Canada, and is located on a foundation of glacial sand, silt and gravel that bites into Lake Erie. This spit of land is slightly more than seven kilometres long by 4.5 kilometres (2.8 mi) wide at its northern base. Established in 1918, Point Pelee was the first national park in Canada to be established for conservation. It was designated as a Ramsar site on 27 May 1987.

<span class="mw-page-title-main">Thousand Islands – Frontenac Arch</span> Geologic region in North America

The Thousand Islands – Frontenac Arch region or the Frontenac Axis is an exposed strip of Precambrian rock in Canada and the United States that links the Canadian Shield from Algonquin Park with the Adirondack Mountain region in New York, an extension of the Laurentian mountains of Québec. The Algonquin to Adirondacks region, which includes the Frontenac Axis or Arch, is a critical linkage for biodiversity and resilience, and one with important conservation potential. The axis separates the St. Lawrence Lowlands and the Great Lakes Lowlands. It has many distinctive plant and animal species. It is one of four ecoregions of the Mixedwood Plains.

<span class="mw-page-title-main">Central Canada</span> Region of Eastern Canada

Central Canada is a Canadian region consisting of Ontario and Quebec, the largest and most populous provinces of the country. Geographically, they are not at the centre of Canada but instead overlap with Eastern Canada toward the east. Because of their large populations, Ontario and Quebec have traditionally held a significant amount of political power in Canada, leading to some amount of resentment from other regions of the country. Before Confederation, the term "Canada" specifically referred to Central Canada. Today, the term "Central Canada" is less often used than the names of the individual provinces.

The Carolinian forest refers to a life zone in eastern North America characterized primarily by the predominance of deciduous (broad-leaf) forest. The term "Carolinian", which is most commonly used in Canada, refers to the deciduous forests which span across much of the eastern United States from the North Carolina northward into southern Ontario, Canada. These deciduous forests in the United States and southern Ontario share many similar characteristics and species hence their association. Today the term is often used to refer to the Canadian portion of the deciduous forest region while the portion in the United States is often referred to as the "Eastern deciduous forest".

<span class="mw-page-title-main">Southwestern Ontario</span> Secondary region in Ontario, Canada

Southwestern Ontario is a secondary region of Southern Ontario in the Canadian province of Ontario. It occupies most of the Ontario Peninsula bounded by Lake Huron, including Georgian Bay, to the north and northwest; the St. Clair River, Lake St. Clair, and Detroit River, to the west; and Lake Erie to the south. To the east, on land, Southwestern Ontario is bounded by Central Ontario and the Golden Horseshoe. The region had a population of 2,796,367 in 2021. It is sometimes further divided into "Midwestern Ontario" covering the eastern half of the area and the heart of Southwestern Ontario encompassing the western half of the region.

<span class="mw-page-title-main">Aspen parkland</span> Temperate grasslands, savannas, and shrublands ecoregion of Canada and the United States

Aspen parkland refers to a very large area of transitional biome between prairie and boreal forest in two sections, namely the Peace River Country of northwestern Alberta crossing the border into British Columbia, and a much larger area stretching from central Alberta, all across central Saskatchewan to south central Manitoba and continuing into small parts of the US states of Minnesota and North Dakota. Aspen parkland consists of groves of aspen, poplar and spruce, interspersed with areas of prairie grasslands, also intersected by large stream and river valleys lined with aspen-spruce forests and dense shrubbery. This is the largest boreal-grassland transition zone in the world and is a zone of constant competition and tension as prairie and woodlands struggle to overtake each other within the parkland.

<span class="mw-page-title-main">Boreal Shield Ecozone (CEC)</span> Largest ecozone in Canada, stretching from Saskatchewan to Newfoundland

The Boreal Shield Ecozone, as defined by the Commission for Environmental Cooperation (CEC), is the largest ecozone in Canada. Covering 1.8 million square kilometres it covers almost 20% of Canada's landmass, stretching from northern Saskatchewan to Newfoundland.

<span class="mw-page-title-main">Geography of Ontario</span>

Ontario is located in East/Central Canada. It is Canada's second largest province by land area. Its physical features vary greatly from the Mixedwood Plains in the southeast to the boreal forests and tundra in the north. Ontario borders Manitoba to the west, Hudson Bay and James Bay to the north, Quebec to the east, and the Great Lakes and the United States to the south. The province is named for Great Lake Ontario, an adaptation of the Iroquois word Onitariio, meaning "beautiful lake", or Kanadario, variously translated as "beautiful water". There are approximately 250,000 lakes and over 100,000 kilometres (62,000 mi) of rivers in the province.

<span class="mw-page-title-main">Hudson Bay Lowlands</span> Wetland located between the Canadian Shield and Hudson Bay

The Hudson Bay Lowlands is a vast wetland located between the Canadian Shield and southern shores of Hudson Bay and James Bay. Most of the area lies within the province of Ontario, with smaller portions reaching into Manitoba and Quebec. Many wide and slow-moving rivers flow through this area toward the saltwater of Hudson Bay: these include the Churchill, Nelson and Hayes in Manitoba, Severn, Fawn, Winisk, Asheweig, Ekwan, Attawapiskat, and Albany in Ontario, and the Harricana, Rupert and Eastmain in Quebec. This is the largest wetland in Canada, and one of the largest in the world. The region can be subdivided into three bands running roughly northwest to southeast: the Coastal Hudson Bay Lowland, Hudson Bay Lowland, and James Bay Lowland.

The Great Lakes-St. Lawrence Lowlands, or simply St. Lawrence Lowlands, is a physiographic region of Eastern Canada that comprises a section of southern Ontario bounded on the north by the Canadian Shield and by three of the Great Lakes — Lake Huron, Lake Erie and Lake Ontario — and extends along the St. Lawrence River to the Strait of Belle Isle and the Atlantic Ocean. The lowlands comprise three sub-regions that were created by intrusions from adjacent physiographic regions — the West Lowland, Central Lowland and East Lowland. The West Lowland includes the Niagara Escarpment, extending from the Niagara River to the Bruce Peninsula and Manitoulin Island. The Central Lowland stretches between the Ottawa River and the St. Lawrence River. The East Lowland includes Anticosti Island, Îles de Mingan, and extends to the Strait of Belle Isle.

<span class="mw-page-title-main">Atlantic Maritime Ecozone</span>

The Atlantic Maritime Ecozone, as defined by the Commission for Environmental Cooperation (CEC), is an ecozone which covers the Canadian provinces of Prince Edward Island, Nova Scotia, and New Brunswick, as well as the Gaspé Peninsula of Quebec. It is adjacent to the Atlantic Marine Ecozone to the east, and the Mixedwood Plains to the west. The roughly-corresponding Level I Ecoregion to this ecozone in the United States Environmental Protection Agency's classification, which is also part of the CEC system, is the Northern Forests ecoregion, though that classification includes the woodlands and swamps of northern Michigan and Minnesota, which are adjacent to the Boreal Shield ecozone.

<span class="mw-page-title-main">Boreal Plains Ecozone (CEC)</span> An ecozone

The Boreal Plains Ecozone, as defined by the Commission for Environmental Cooperation (CEC), is a terrestrial ecozone in the western Canadian provinces of Manitoba, Saskatchewan and Alberta. It also has minor extensions into northeastern British Columbia and south-central Northwest Territories. The region extends over 779,471 km2, of which 58,981 km2 is conserved.

<span class="mw-page-title-main">Eastern Great Lakes and Hudson Lowlands (ecoregion)</span>

The Eastern Great Lakes and Hudson Lowlands region extends along the south shores of Lake Erie and Lake Ontario and the St. Lawrence River to Lake Champlain, and south down the Hudson River. It is primarily within the state of New York, with smaller portions in Vermont, Pennsylvania, and Ohio. In the north it meets the Mixedwood Plains Ecozone of Canada in eastern Ontario and southern Quebec. It is mostly temperate deciduous forest and agricultural land.

<span class="mw-page-title-main">Forests of Canada</span>

The forests of Canada are located across much of the country. Approximately half of Canada is covered by forest, totaling around 2.4 million km2. Over 90% of Canada's forests are owned by the public. About half of the forests are allocated for logging.

<span class="mw-page-title-main">Southern Hudson Bay taiga</span> Taiga ecoregion of Canada

The Southern Hudson Bay taiga is a terrestrial ecoregion, as classified by the World Wildlife Fund, which extends along the southern coast of Hudson Bay and resides within the larger taiga biome. The region is nearly coterminous with the Hudson Plain, a Level I ecoregion of North America as designated by the Commission for Environmental Cooperation (CEC) in its North American Environmental Atlas.

<span class="mw-page-title-main">Long Point National Wildlife Area</span> National Wildlife Protected area in Ontario, Canada.

The Long Point National Wildlife Area is a Protected area of Canada and one of ten National Wildlife Areas in Ontario. It is the core area of the Long Point Biosphere Reserve, created in 1986, and has been recognized as a Ramsar site since 1982.

Winagami Wildland Provincial Park is a wildland provincial park in northern Alberta, Canada. The park was established on 26 August 1998 and has an area of 17,439.886 hectares. The park is included in the Upper Athabasca Region Land Use Framework. The park is named for Winagami Lake which is adjacent to the park.

References

  1. 1 2 "Urban Corridor". Mixedwood Plains Ecozone. Environment Canada. Archived from the original on June 22, 2004. Retrieved January 19, 2012.
  2. 1 2 3 4 "Canada's Ecozones". Space for Species. Archived from the original on December 16, 2007. Retrieved January 19, 2012.
  3. 1 2 Bernhardt, Torsten. "Mixedwood Plains". Canada's Ecozones, Canadian Biodiversity project. McGill University, Redpath Museum. Retrieved 2008-02-02.
  4. ↑ Rowe. J.S. 1972. Forest Regions of Canada. Canadian Forest Service, Department of Fisheries and the Environment, Ottawa, Ontario, Canada. 172 p. plus map.
  5. 1 2 Hills, G.A. 1961. The Ecological Basis for Land Use Planning. Ontario Department of Lands and Forests, Research Branch, Research Report No. 46, Toronto.
  6. ↑ "North American Environmental Atlas; Terrestrial Ecoregions". Archived from the original on July 24, 2012. Retrieved June 26, 2012.
  7. ↑ "Mixedwood Plains". Canadian Geographic . Retrieved January 19, 2012.
  8. ↑ Eyles, N. Ontario Rocks: Three Billion Years of Environmental Change. Fitzhenry & Whiteside, Markham, Ontario. 339 p.
  9. ↑ Rowe. J.S. 1972. Forest Regions of Canada. Canadian Forest Service, Department of Fisheries and the Environment, Ottawa, Canada. 172 p. plus map. p 89.
  10. 1 2 3 Johnson, L. (ed.) 2007. The Natural Treasures of Carolinian Canada: Discovering the Rich Natural Diversity of Ontario's Southwestern Heartland. Lorimer/Carolinian Canada Coalition.
  11. ↑ Secretariat, Treasury Board of Canada. "National Ecological Framework for Canada - Open Government Portal". open.canada.ca. Retrieved 2020-11-07.
  12. 1 2 "Landforms and Climate of the Mixedwood Plains Ecozone". Mixedwood Plains Ecozone. Environment Canada. Archived from the original on January 25, 2007. Retrieved January 19, 2012.
  13. ↑ Braun, E. L. 1950. Deciduous Forests of Eastern North America. New York: Hafner.
  14. ↑ Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Chapter 2.
  15. ↑ Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Chapter 2.
  16. ↑ Maynard, L., and Wilcox, D.A., 1997, Coastal wetlands of the Great Lakes—State of the Lakes Ecosystem Conference 1996 background paper: Environment Canada and U.S. Environmental Protection Agency, EPA 905–R–97–015b, 99 p.
  17. ↑ "Mixedwood Plains Ecozone". Teacher Resource Centre: Terrestrial Ecozones of Canada. Parks Canada. Retrieved January 19, 2012.
  18. ↑ "Total area protected by ecozones, 2010". Protected Areas Data. Environment Canada. Retrieved January 19, 2012.
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