Great Lakes–St. Lawrence Lowlands

The Great Lakes-St. Lawrence Lowlands includes 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 Saint Lawrence River to the Strait of Belle Isle The Geological Survey of Canada published an updated map in 2014 defining the boundaries of the Great Lakes-St. Lawrence Lowlands physiographic region. Sub-regions The Great Lakes-St. Lawrence's lowlands include three sub-regions. West Lowland The southwest region of the Lowlands which is in southern Ontario and northern New York and Vermont is divided by the Niagara Escarpment, which extends northwest from the Niagara River to the Bruce Peninsula and Manitoulin Island. This subregion includes the Bruce Peninsula to the northwest and the Niagara Peninsula, which is the warmest and most intensely cultivated part of the ecozone. Central Lowland The Central Lowland stretches between the Ottawa River and the Saint Lawrence River and extends to Québec city. Major cities include Trois-Rivières. The Lowlands include a small area on the north shore near Québec City. The St. Lawrence Lowlands are underlain by marine and lacustrine clays and bedrock outcrops of Paleozoic limestone. In the north it is bounded by the Laurentian Highlands. East Lowland The East Lowland includes Anticosti Island, Îles de Mingan, the Strait of Belle Isle and the Newfoundland Coastal Lowland. To the south it is bordered by the Eastern Quebec Uplands. == Physiographic region ==

The Great Lakes-St. Lawrence Lowlands is listed as one of Canada's seven physiographic regions, which in turn have their own subregions and divisions—distinguished by topography and geology. == Topography ==

The landforms of the Great Lake – St. Lawrence Lowlands, with its rolling hills and slopes, were carved by glacial streams. Two of the most prominent geological features include the Niagara Escarpment and the Frontenac Axis. The Niagara Escarpment bifurcates the region from Niagara Falls to the northern tip of the Bruce Peninsula, then extends to Manitoulin Island. The Frontenac Axis, is an exposure of Canadian shield rocks that extends south to the St. Lawrence River near Kingston, creating the Thousand Islands. Geology Peninsular Ontario lowlands are separated from the lowlands of the lower St. Lawrence at the Thousand Islands by the Frontenac Axis, where ancient granite of the Canadian Shield cross over and become the Adirondacks. The next notable pinching occurs at Quebec City, where again the Shield meets the shore. Anticosti Island and Newfoundland, both being islands, are separated by stretches of open saltwater. Due to the presence of a deep fault line, this water eventually siphoned into the ocean. Thus, the primary defining historic feature of the lowlands is the presence of deep soils within the watershed and estuary of the St. Lawrence River. This feature occurs in more than one distinct Peninsular Ontario south and west of and the surrounding area, including the lower Ottawa Valley and St. Lawrence below the Thousand Islands, as far as Quebec City. A narrow ribbon of land along both shores of the lower St Lawrence Estuary, hemmed in on the north shore by the Canadian Shield and on the south which faces into the flow of the river, has accreted alluvial soils from the Great Lakes basin. Glacial legacy Huge glacial seas such as Lake Agassiz, and the Champlain Sea (in the east), and vast, continent-wide 2 kilometres thick ice sheets contributed to the formation of the region. The present form of Great Lakes–St. Lawrence basin developed about 7,000 years ago. It began to emerge from glacial sheets about 14,000 years ago. == Ecozones and regions ==

The extent of the Great Lakes-St. Lawrence Lowlands physiographic region, as defined by Geological Survey of Canada, differs from the boundaries of ecozones defined by the Canadian Council on Ecological Areas (CCEA) and the World Wildlife Fund (WWF), for example. StatsCan said that, by 2006, 80 percent of the St. Lawrence Lowlands were covered by forests and cropland. The ecoregion produced 38.5 percent of Canada's total corn cropland, 22.6 percent of Canada's maple tree taps, 23.6 percent of the "Canadian pig population and 32.9 percent of Canadian dairy cows". and is home to nearly half of Canada's population, including its two largest cities, Toronto, Ontario and Montreal, Quebec. The World Wildlife Fund (WWF) describes the Great Lakes-St. Lawrence River lowlands as the Eastern Great Lakes lowland forests ecoregion. The lowland forest area stretches across the lowlands of the American states of New York and Vermont, and the Canadian provinces of Ontario and Quebec. The New York and Vermont lowlands surround the Adirondack Mountains. The Quebec lowlands are along the St. Lawrence River. The lowlands in southern Ontario stretch between Lake Ontario and the Georgian Bay/Lake Huron region. == Hydrographic system ==

The Great Lakes – St. Lawrence hydrographic system—with a surface area of 1.6 million km2—is the third largest in North America and one of the largest in the world. Three aquifers of the St. Maurice Delta Complex in the Central St. Lawrence Lowlands provide drinking water for Trois-Rivières and most of the other municipalities in the region. The premiers of the provinces of Quebec and Ontario and eight Great Lakes governors from Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin signed the Great Lakes–Saint Lawrence River Basin Sustainable Water Resources Agreement on December 13, 2005, which came into force in 2015. It is a good faith agreement detailing the management and use of the Great Lakes Basin's water supply. It was signed on December 13, 2005. It succeeds and builds on the Great Lakes Charter signed in 1985 and its Annex signed in 2001. == Economy ==

Even though the Great Lakes-St. Lawrence Lowlands is the smallest landform region in Canada, Southern Ontario and Quebec have a dense population and are home to about 50 percent of the population of Canada. Southern Ontario's Golden Horseshoe and the St. Lawrence lowlands formed Canada's industrial and manufacturing heartland. Stretching from Windsor, Ontario, along the shores of Lake Ontario to Quebec City, the formed a "densely populated urban ribbon at a length of some 1000 km and a width of 100-300 km". == Resources ==

The Great Lakes-St. Lawrence region of Canada provides drinking water to over 8.5 million Canadians. The region holds "largest freshwater system in the world" representing over 80 per cent of freshwater in North America. There is Utica shale, the stratigraphical unit of Upper Ordovician age occupies about 16,000 square kilometres in the Central Lowlands subregion of the St. Lawrence Lowlands (SLL) in the administrative regions of Montérégie, Centre-du-Québec and Chaudière-Appalaches. == Wildlife and waterfowl ==

There are about 3,500 species of animals and plants in the Lowlands. Characteristic wildlife includes the black bear, grey wolf, coyote, beaver, snowshoe hare, white-tailed deer, lynx, moose, and otter. Birds include waterfowl, warblers, blue birds, red-winged black birds, eagles, and hawks. == Urban communities ==

Major cities in the Lowlands include "Quebec City, Toronto, Montreal, Trois-Rivières, Saint-Hyacinthe, Cornwall, Brockville, Ottawa/Gatineau, and Pembroke." == First Nations ==

For thousands of years, Indigenous peoples have been living along both sides of the Saint Lawrence River. The Great Lakes-St. Lawrence Lowlands was the traditional lands of the Mohawk—the most easterly tribe of the Iroquoian-speaking Haudenosaunee Confederacy, the Algonquian and Iroquoian peoples, and the Cree—one of the largest groups of First Nations in North America. == See also ==