Boreal Cordillera
Encyclopedia
The Boreal Cordillera is a Canadian
terrestrial ecozone
occupying most of the northern third of British Columbia
and southern half of the Yukon
. Within it is found Kluane National Park and Reserve
, and a small portion of the southern range of Nahanni National Park Reserve
. Most of the area's population is based in the city of Whitehorse
, and it contains most of the Yukon's population. The portion in British Columbia is barely populated.
The main economic activity is mining
, particularly of gold
, which discovery in the region led to the Klondike Gold Rush
. In addition to the area's rich mineral deposits, active industries exist in forestry
and tourism
.
ous ecozone is between the Montane Cordillera Ecozone to the south-east and the Taiga Cordillera Ecozone to the north. The three zones contain the Canadian Rockies
. To the east are the Taiga Plains
, and to the west is Alaska
, though the ecozone is also adjacent to narrow strips of the Pacific Maritime
. It is characterized by tall peaks and extensive plateaux. The northern plateaux within the ecozone have a fairly gentle terrain, broken by numerous watercourses running through them, and are separated by wide valley
s and their lowland
s.
Just over 15% of the Boreal Cordillera, or roughly 73,320 km² consists of wetland
s, of which 92% is treed wetland. It covers a total area of 471,400 km², with 241,240 km² of forest cover, of which 78.6% is softwood
, 17.8% is mixedwood, and 3.6 is hardwood
. The spruce beetle has been proliferating since the 1990s, and has destroyed vast areas of the spruce forest. The ecozone contains four forest regions - tundra, sub-alpine, coast, and boreal. There is also concern that the softwood harvest in southeastern Yukon does not have adequate natural regeneration.
, much less than the 1000 to 1500 mm levels in the eastern mountains, and the even higher levels in the western mountains. Snow
fall accounts for 35 to 60% of all precipitation. Winters are long and cold, with January mean temperatures between -15°C and -27°C. Summers are warm but short, with July mean temperatures between 12°C and 15°C.
Alpine weather is more typical beyond the tree line at elevations above 1000 m, where frost can develop year-round. Average temperatures here remain below freezing for most of the year, and snowfall accounts for at least 70% of precipitation. Permafrost is typical in these regions, allowing for the growth of only shrub
s, moss
es and lichen
s.
Sudden violent storms may occur in the area during the summer, usually due to moist air masses arriving from the Pacific Ocean
. Usually, however, the Pacific moderates the climate in this ecozone.
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
terrestrial ecozone
Ecozones of Canada
The ecozones of Canada consist of fifteen terrestrial and five marine ecozones in Canada. These are further subdivided into 53 ecoprovinces, 194 ecoregions, and 1021 ecodistricts...
occupying most of the northern third of British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
and southern half of the Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....
. Within it is found Kluane National Park and Reserve
Kluane National Park and Reserve
Kluane National Park and Reserve are two units of Canada's national park system, located in the extreme southwestern corner of Yukon Territory. Kluane National Park Reserve was established in 1972, covering 22,016 square kilometres....
, and a small portion of the southern range of Nahanni National Park Reserve
Nahanni National Park Reserve
Nahanni National Park Reserve in the Dehcho Region of the Northwest Territories, Canada, approximately west of Yellowknife, protects a portion of the Mackenzie Mountains Natural Region. The centrepiece of the park is the South Nahanni River. Four noteworthy canyons reaching in depth, called...
. Most of the area's population is based in the city of Whitehorse
Whitehorse, Yukon
Whitehorse is Yukon's capital and largest city . It was incorporated in 1950 and is located at kilometre 1476 on the Alaska Highway in southern Yukon. Whitehorse's downtown and Riverdale areas occupy both shores of the Yukon River, which originates in British Columbia and meets the Bering Sea in...
, and it contains most of the Yukon's population. The portion in British Columbia is barely populated.
The main economic activity is mining
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
, particularly of gold
Gold
Gold is a chemical element with the symbol Au and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a...
, which discovery in the region led to the Klondike Gold Rush
Klondike Gold Rush
The Klondike Gold Rush, also called the Yukon Gold Rush, the Alaska Gold Rush and the Last Great Gold Rush, was an attempt by an estimated 100,000 people to travel to the Klondike region the Yukon in north-western Canada between 1897 and 1899 in the hope of successfully prospecting for gold...
. In addition to the area's rich mineral deposits, active industries exist in forestry
Forestry
Forestry is the interdisciplinary profession embracing the science, art, and craft of creating, managing, using, and conserving forests and associated resources in a sustainable manner to meet desired goals, needs, and values for human benefit. Forestry is practiced in plantations and natural stands...
and tourism
Tourism
Tourism is travel for recreational, leisure or business purposes. The World Tourism Organization defines tourists as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes".Tourism has become a...
.
Geography
This mountainMountain
Image:Himalaya_annotated.jpg|thumb|right|The Himalayan mountain range with Mount Everestrect 58 14 160 49 Chomo Lonzorect 200 28 335 52 Makalurect 378 24 566 45 Mount Everestrect 188 581 920 656 Tibetan Plateaurect 250 406 340 427 Rong River...
ous ecozone is between the Montane Cordillera Ecozone to the south-east and the Taiga Cordillera Ecozone to the north. The three zones contain the Canadian Rockies
Canadian Rockies
The Canadian Rockies comprise the Canadian segment of the North American Rocky Mountains range. They are the eastern part of the Canadian Cordillera, extending from the Interior Plains of Alberta to the Rocky Mountain Trench of British Columbia. The southern end borders Idaho and Montana of the USA...
. To the east are the Taiga Plains
Taiga Plains
The Taiga Plain is a Canadian terrestrial ecozone that covers most of the western Northwest Territories, extending to northwest Alberta, northeast British Columbia and slightly overlapping northeastern Yukon....
, and to the west is Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
, though the ecozone is also adjacent to narrow strips of the Pacific Maritime
Pacific Maritime
The Pacific Maritime Ecozone is a Canadian terrestrial ecozone, spanning a strip approximately 200 kilometres wide along the British Columbia coast, then narrowing along the border with Alaska...
. It is characterized by tall peaks and extensive plateaux. The northern plateaux within the ecozone have a fairly gentle terrain, broken by numerous watercourses running through them, and are separated by wide valley
Valley
In geology, a valley or dale is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys...
s and their lowland
Lowland
In physical geography, a lowland is any broad expanse of land with a general low level. The term is thus applied to the landward portion of the upward slope from oceanic depths to continental highlands, to a region of depression in the interior of a mountainous region, to a plain of denudation, or...
s.
Just over 15% of the Boreal Cordillera, or roughly 73,320 km² consists of wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s, of which 92% is treed wetland. It covers a total area of 471,400 km², with 241,240 km² of forest cover, of which 78.6% is softwood
Softwood
The term softwood is used to describe wood from trees that are known as gymnosperms.Conifers are an example. It may also be used to describe trees, which tend to be evergreen, notable exceptions being bald cypress and the larches....
, 17.8% is mixedwood, and 3.6 is hardwood
Hardwood
Hardwood is wood from angiosperm trees . It may also be used for those trees themselves: these are usually broad-leaved; in temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen.Hardwood contrasts with softwood...
. The spruce beetle has been proliferating since the 1990s, and has destroyed vast areas of the spruce forest. The ecozone contains four forest regions - tundra, sub-alpine, coast, and boreal. There is also concern that the softwood harvest in southeastern Yukon does not have adequate natural regeneration.
Climate
The interior intermontane plateau receive about 400 mm of annual precipitationPrecipitation (meteorology)
In meteorology, precipitation In meteorology, precipitation In meteorology, precipitation (also known as one of the classes of hydrometeors, which are atmospheric water phenomena is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation...
, much less than the 1000 to 1500 mm levels in the eastern mountains, and the even higher levels in the western mountains. Snow
Snow
Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Since snow is composed of small ice particles, it is a granular material. It has an open and therefore soft structure, unless packed by...
fall accounts for 35 to 60% of all precipitation. Winters are long and cold, with January mean temperatures between -15°C and -27°C. Summers are warm but short, with July mean temperatures between 12°C and 15°C.
Alpine weather is more typical beyond the tree line at elevations above 1000 m, where frost can develop year-round. Average temperatures here remain below freezing for most of the year, and snowfall accounts for at least 70% of precipitation. Permafrost is typical in these regions, allowing for the growth of only shrub
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
s, moss
Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
es and lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...
s.
Sudden violent storms may occur in the area during the summer, usually due to moist air masses arriving from the Pacific Ocean
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
. Usually, however, the Pacific moderates the climate in this ecozone.