The Taiga of North America is a Level I ecoregion of North America designated by the Commission for Environmental Cooperation (CEC) in its North American Environmental Atlas. The taiga ecoregion includes much of interior Alaska as well as the Yukon forested area, and extends on the west from the Bering Sea to the Richardson Mountains in on the east, with the Brooks Range on the north and the Alaska Range on the south end. It is a region with a vast mosaic of habitats and a fragile yet extensive patchwork of ecological characteristics. All aspects of the region such as soils and plant species, hydrology, and climate interaction, and are affected by climate change, new emerging natural resources, and other environmental threats such as deforestation. These threats alter the biotic and abiotic components of the region, which lead to further degradation and to various endangered species.
Flora, fauna, and soil
Soils and plant species The main type of soil in the taiga is Spodosol. These soils contain a Spodic horizon, a sandy layer of soil that has high accumulations of iron and aluminum oxides, which lays underneath a leached A horizon. The color contrast between the Spodic horizon and the overlying horizon is very easy to identify. The color change is the result of the migration of iron and aluminum oxides from small, but consistent amounts of rainfall from the top horizon to the lower horizon of the soil. The decomposition of organic matter is very slow in the taiga because of the cold climate and low moisture. With the slow decomposition of organic matter, nutrient cycling is very slow and the nutrient level of the soil is also very low. The soils in the taiga are quite acidic as well. A relatively small amount of rainfall coupled with the slow decomposition of organic material allows the acidic plant debris to sit and saturate the top horizons of the soil profile. As a result of the infertile soil, only a few plant species can really thrive in the taiga. The common plant species in the taiga are coniferous trees. Not only do conifer trees thrive in acidic soils, they actually make the soil more acidic. Acidic leaflitter (or needles) from conifers falls to the forest floor and the precipitation leaches the acids down into the soil. Other species that can tolerate the acidic soils of the taiga are lichens and mosses, yellow nutsedge, and water horsetail. The depth to bedrock has an effect on the plants that grow well in the taiga as well. A shallow depth to bedrock forces the plants to have shallow roots, limiting overall stability and water uptake.
Keystone species Beaver, Canadian lynx, bobcat, wolverine, and snowshoe hare are all keystone species in the taiga area. These species are keystone because they have learned to adapt to the cold climate of the area and are able to survive year-round. These species survive year-round in taiga by changing fur color and growing extra fur. They have adapted to use each other to survive too. All of the predators depend on the snowshoe hare at some point during the year. All of the species also depend on forests in the area for shelter.
Endangered species The taiga is inhabited by many species, some of which are endangered, and include the Canadian lynx, gray wolf, and grizzly bear. The Canadian lynx is one well-known animal to inhabit the North American taiga region and is listed as threatened in the U.S. The mother lynx will have a litter of about 4 kittens in the spring. Following the birth, the female is the sole caretaker, nursing them for about 5 months and teaching them to hunt. They will stay with her until the next breeding season. According to the USDS Forest Service, protection for the lynx has increased since 2000, which marks the date it became protected under the Endangered Species Act. Since much of the lynx's habitat is land managed by the agency, efforts to maintain and increase the habitat for the Canadian lynx using forest management plans are underway. The taiga region is also interspersed with various plant species. The endangered or threatened species include Labrador tea, lady's slipper orchid, helleborine orchid, longleaf pine, lingonberry plant, Newfoundland pine marten, Methuselahs beard, lodgepole pine, and Scots pine. The life history of longleaf pine is a tree species that has been around for quite some time and can reach more than 250 years in age. To begin the tree's life, a seed falls from the parent in October to late November awaiting water to begin germination in a few weeks. Those individuals that make it, will enter what is known as the grass stage. During this stage, the roots are established, and the bud of the tree is protected from fire. Years later, the longleaf will reach about 6–10 feet (1.8–3.0 m) in height and the diameter will increase with time. Somewhere around 30 years after the trees will begin to produce cones with fertile seeds and average about 110 feet (34 m) at maturity. One recent study discusses the effects of logging in the 1950s on pine species. Since then, conservation efforts have increased the number of pine (and other) tree species. The Nature Conservancy is prioritizing its protection efforts to rebuild long-leaf pine forests through land purchases, conservation easements, and management of land sites. Restoration is also a large part of efforts to ensure the long-leaf pine remains extant. By planting seedlings, controlling competitive vegetation, and controlling burning methods, scientists and volunteers are working to increase the number of long-leaf pine.
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