Boreal Forest/ Taiga Biome PowerPoint

Boreal Forest / TaigaCharlie Wetherbee & Jordan Lautt • AP Environmental Science 2˚

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Global DistributionBoreal Forest / Taiga



DistributionBoreal Forest / Taiga


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• Boreal forests comprise the largest terrestrial biome, covering approximately 17% of Earth’s land area.

• Canada, Russia, and Scandinavia are almost entirely covered by taiga; the biome is defined by its climate, which occurs almost exclusively in the high latitudes of the northern hemisphere. There is no taiga in the southern hemisphere except at altitudes conducive to these conditions.

• These forests cover large regions of northern North America and Eurasia, usually extending from 50˚ to 60˚N. They are bordered on the south by temperate forests in North America and steppes in Eurasia, and recede to arctic tundra at their northern extremes.

Climate ConditionsBoreal Forest / Taiga

• Boreal forests are characterized by their harsh climate, a result of their high latitude. This location on the globe creates extreme temperature swings between seasons as well as months of bitter cold in the absence of sunlight.

• Verkhoyansk, Russia, located in the heart of the Siberian taiga, often experiences winter lows below -90˚F and summer highs above 90˚F, the widest temperature range on the planet.

• Summers are short, humid, and warm. Winters last at least six months, during which the average temperature is below freezing; snow can remain for nine months. Tundra and ice caps are the only terrestrial biomes that experience colder

temperatures than the taiga.





Climate ConditionsBoreal Forest / Taiga

• High latitude locations prevent the sun from reaching far above the horizon even in summer– winters months can experience almost perpetual night.



• Most precipitation occurs as summer rain, though boreal forests only receive 12-30” of precipitation annually. Low evaporation rates enables denser vegetation growth.

• Precipitation also occurs in the form of summer fog and heavy winter snow. Precipitation remains relatively constant throughout the year.

Dominant Flora and FaunaBoreal Forest / Taiga

• There are two common types of boreal forest. Closed forest consists of densely spaced trees and mossy forest floor, while lichen woodland, found at higher latitudes, has trees that are more sparsely distributed and a ground cover of lichen.




• Trees in the taiga are almost exclusively coniferous– pines, firs, spruces, and larches. These trees have dark green needles in order to minimize water loss, protect against the cold, and absorb more solar energy. Roots are shallow due to the thin soil, and can be chemically altered depending on the season. Conical shape, needles, and drooping limbs reduce the snow load.

• Boreal forests have low biological diversity, but do support some other non-coniferous species. Lichens and mosses grow on the shaded forest floor and become dormant during winter months when buried by snow. Grasses and other herbacious plants grow during the warmer months, and wildflowers often spring up from the melting snow in early summer. Broadleaf trees like aspen, birch, and willow can occasionally be found in the taiga.


• Large mammals like bears, caribou, foxes, wolves, lynx, and moose dominate the taiga due to their ability to fight the bitter cold or hibernate.

• Several tiger species are found in the southern boreal forests of Asia, most notably the highly endangered Siberian tiger.

• Rodents and other small animals like wolverines, beavers, muskrats, and snowshoe hares also populate the forest. These are herbivorous, and they provide the majority of the food source for some of the carnivores listed above.




• Boreal forests are also a vital habitat for migrating birds. Billions nest and reproduce in the forests during their short but temperate summer. And estimated 1.4 billion birds are hatched each summer in Canadian forests alone.



Challenges of the ForestsBoreal Forest / Taiga

• Harsh climate (cold, long winters, large seasonal temperature swings) and low energy levels (less sunlight absorption) limit biodiversity and production.

• The short growing season limits the amount of undergrowth, which is more susceptible to cold damage than well-adapted conifers. This also results in fewer primary consumers and less available biomass in general.

• Many taiga regions are very dry, almost desert-like. Snow that remains on the ground for much of the year cannot be used until it melts.

• Soil is thin and poor. Nutrients are often in short supply, and smaller producers can only take hold when snow does not cover the forest floor. Low biodiversity and energy flow result in few nutrients, further hindering productivity.

Human ThreatsBoreal Forest / Taiga

• Boreal forests have been subject to huge amounts of deforestation because they supply the majority of wood for timber and paper products.


• Forests often cover land with large fossil fuel reserves. Forests in Siberia have been compromised because of the oil boom that is revitalizing the economy in that barren landscape. Concern for the environment is minimal because it threatens the livelihood of the people. The growth of the oil sands industry in Canada is even more damaging because strip-mining is the first step to retrieving the oil.


• Global warming poses perhaps the largest challenge to the world’s boreal forests, with the highest temperature increases expected at the high latitudes where the forests are found. As the climate warms, the taiga’s characteristic cold weather and long winters will become milder, allowing different organisms to be able to survive and potentially causing steppes or more temperate forests to take over in the taiga’s southern areas.

SourcesBoreal Forest / Taiga

Cover image: Encinas, Javier. “Canada's Winter Wonderland (Banff, AB)”. 9 Jan. 2010. Online image. Flickr. 23 Feb. 2010.

<http://www.flickr.com/photos/forevernomad/4256519166>

Main sources:"Boreal Forest." Encyclopædia Britannica. 2010. Encyclopædia Britannica Online. 23 Feb. 2010

<http://www.britannica.com/EBchecked/topic/74016/boreal-forest>.

Wikipedia contributors. "Taiga." Wikipedia, The Free Encyclopedia. 24 Feb. 2010. The Wikimedia Foundation. 25 Feb. 2010. <http://en.wikipedia.org/wiki/Taiga>

Cunningham, William P., and Mary Cunningham. Environmental Science, A Global Concern. 10th ed. New York: McGraw Hill, 2008.

SourcesBoreal Forest / Taiga

Other sources and images:

http://birds.cornell.edu/bigyear/photo-gallery/alaska/YukonFlats_vyn.jpg

http://www.birds.cornell.edu/bigyear/field-notes/AKtravellog

http://www.ucmp.berkeley.edu/exhibits/biomes/forests.php#boreal

http://www.britannica.com/EBchecked/topic/74016/boreal-forest

http://www.borealforest.org/world/world_overview.htm

http://www.team-bhp.com/forum/attachments/travelogues/163764d1248421124-more-pics-hyd-bandipur-madumalai-nagarahole-dark-forest.jpg

http://www.bbc.co.uk/schools/gcsebitesize/geography/images/eco_023.gif

http://desertplanet.files.wordpress.com/2009/01/russia-siberia-cold-snow1.jpg

http://upload.wikimedia.org/wikipedia/commons/2/2d/Picea_glauca_taiga.jpg

http://www.nasa.gov/images/content/418469main_10YearAverage_full.jpg

http://en.wikipedia.org/wiki/File:P.t.altaica_Tomak_Male.jpg

http://wikimedia.org/wikipedia/commons/9/91/BaikalForest_%28pixinn.net%29.jpg

http://www.somers.k12.ct.us/~mporter/images/52-19a-PopCycleHareLynxPhot.jpeg

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Boreal Forest/ Taiga Biome PowerPoint