Alberta Life Zones
Last Review/Updated: May 31, 2002
Life Zones
All forms of life require certain conditions in which to live and successfully reproduce. These conditions are supplied by a plant or animal's environment. Every environment is created by the interaction of air, soil, water, plants and animals, under the influence of climate and other factors. There are many possible combinations and variations of these factors and thus environments can vary widely from place to place. As environments vary, so do the kinds of plants and animals that are adapted to live in them.
Alberta
is a large province with a total area of approximately 660 000
km2 (255 000 mi.2). A major characteristic
of the province is its diverse topography, ranging from flat, sometimes
featureless plains to the high mountains of the west. These differences
help create a variety of environments, from the prairie steppe in the
southeast corner of the province to the mixedwood, boreal forest of
the north, and the treeless alpine of the Rocky Mountains. This range
of environments can be divided into major"life zones" that are characterized
by particular groupings of plants and animals. The following are general
descriptions of each major life zone in Alberta.
Alpine
This zone is only found in the highest Rocky Mountains where it is too cool for trees to grow. In Alberta, timberline (upper altitudinal limit of tree growth) runs irregularly from 1800 to 2400 m (6000 - 8000 ft.) above sea level. Timberline drops progressively to the north until it meets the treeless tundra of the Arctic. Permanent snowfields and glaciers are common in this zone. Plant life is low-lying and generally sparse, being found in rocky habitats, moist meadows, and along streamcourses.
Montane
Timberline forms the upper limit of this zone. The zone is characterized by forests of coniferous trees, such as Engelmann spruce and subalpine fir at higher elevations; and white spruce and lodgepole pine at lower elevations.
Foothill
This zone is similar to the lower portion of the montane zone, except that it is generally drier, receiving less precipitation than areas closer to the high mountains. Forests of white spruce, lodgepole pine, and poplar are often broken by tracts of grassland. This mosaic of vegetation provides good habitat for a variety of wildlife.
Mixedwood
Usually called the boreal forest, this zone forms a continuous belt from Newfoundland and Labrador to Alaska. In Alberta, the forests are characterized by white and black spruce and jack pine. These coniferous stands are often interspersed with deciduous poplar and birch (hence the name "mixedwood").
Parkland
This south-central belt is a transition between the mixedwood forests to the north and west and the drier prairies to the south and east. Stands of poplar are interspersed with grasslands and meadows, giving areas in the zone a parklike appearance. This is rich agricultural land with black soils and ample rainfall. Mixed farming has altered much of the original vegetative cover. Small islands of this zone occur in the Peace River region.
Prairie
The most striking feature of this zone is the absence of trees, except in river valleys and coulees where moisture is sufficient to support cottonwood, poplar and other species. Grassland and sagebrush plains predominate. Much of the region is ranching country.
Lowlands
This zone is basically muskeg and bog. Black spruce and tamarack are common tree species associated with this moist environment.
