Boreal Forest or Taiga Biome

Key Features of the Boreal Forest BiomeThis biome has short summers and long cold winters. It has moderate precipitation. A few species of evergreen or coniferous trees like pine, spruce, fir, cedar and larch dominate the plant cover. Coniferous trees are adapted to survive the cold climate and acidic, poorly drained soils. The Taiga terrain (Russian word) alternates between bogs and coniferous forests.

Key Features of the Boreal Forest BiomeTree adaptations like short branches, waxy needles, and resinous bark help to reduce moisture loss and to keep the trees warmer in winter. The long shallow roots of the conifers maximize nutrient absorption while their tough cones protect their seeds from animals and birds. By retaining their needles year round, conifers are able to absorb sunlight year round.

Key Features of the Boreal Forest BiomeTrees in this biome are typically closely –spaced (except in bog areas) which means little light penetrates to ground level, leading to sparse ground-level vegetation. The waxy, acidic conifer needles shed at various times decay slowly due to the overall cold climate which produces a thick mat of needles covering the ground.

Boreal Forest Food WebBoreal forest webs are somewhat simplified with less species of plants and animals present and with animals that are more generalized in their eating habits.

Location of Boreal Forests or Taiga ForestsBoreal forests are located north of 50-60 degrees north latitude. Sixty percent of Canada is covered by Boreal Forests but only 14% of Canada’s population live in Boreal Forest Biomes.

Climate Favouring a Boreal Forest BiomeCold climates (-54 C to 21 C, yearly average temperature ranges from -4 C to 3 C) with moderate precipitation (from 300-840 mm yearly total) favour the formation of Boreal Forests.

Boreal Forest SoilsTaiga soils tend to be highly acidic due to the layers of acidic needles slowly decomposing above the ground. Organic matter slowly forms black humus which gets strongly leached from the upper A horizon into the lower B horizon. These soils are nutrient poor with a very slow recycling of organic matter back into nutrients for reabsorbing. Few organisms live in these highly acidic soils which often are also poorly drained.

Generalized Organisms Living in Taiga RegionsThe organisms living in Boreal Forests are generalized which means they have general niches (professions) they can feed on a variety of organisms rather than just one particular organism.

Biomass Allocation in Boreal ForestsBoreal Forests are just behind tropical rainforests in their area they cover (1,509 million hectares compare to Tropical rainforest area of 1,756 million hectares). Boreal forest are also just behind Temperate and Tropical rainforests in the amount of living plant carbon they have (78 Pg C for Boreal Forests compared to 159 Pg C for Tropical rainforests – 1 Pg = 1 x 1015 g). But Boreal forests have more soil C (625 Pg) and total C (703) than tropical rainforests which have soil C of 216 Pg and total C of 375 Pg.

Forest Structure in a Boreal ForestA Boreal Forest has a canopy layer but not much of a shrub or herb layer since not much light penetrates to beneath the trees. Where there are openings, some smaller trees and shrubs may thrive as well as herbs, especially in open bog areas.

Boreal Forest AnimalsMoose

Boreal Forest AnimalsBear

Boreal Forest AnimalsLynx

Boreal Forest AnimalsBadger

Boreal Forest AnimalsBeaver

Boreal Forest AnimalsSquirrel

Boreal Forest AnimalsMigratory Birds (Ex: Arctic Tern, Solitary Sandpiper)

Boreal Forest PlantsWhite and Black Spruce

Boreal Forest PlantsJack Pine

Boreal Forest PlantsLarch is a deciduous conifer.

Boreal Forest PlantsBalsam Fir

Boreal Forest PlantsSphagnum Moss

Boreal Forest PlantsThe Boreal Bog plant called a Pitcher plant has vase-like structures filled with water and digesting enzymes. The rim of the “pitcher” is slippery and on the inside there are fine hairs pointing downwards, trapping insects which slip into the pitcher. They are then digested and absorbed by the plant. In this way, the plant gets extra nutrients in the nutrient-poor environment in which it lives.

Boreal Forest PlantsThe Venus Fly Trap is another bog plant that provides extra nutrients for itself by capturing and eating organisms that walk into its traps. When sensing cells on both sides of the trap are triggered, the trap closes on the organism and the plant then produces digesting enzymes to dissolve the organism whose nutrients are then absorbed.

Human Impact on Boreal ForestsHydroelectric dams in Manitoba (The Seven Sisters), Ontario (Smoky Falls Rapids)and Quebec have flooded large tracts of Boreal forest.

Human Impact on Boreal ForestsExtraction of fossil fuels (like Alberta’s Tar Sands) has led to the clearing of some Boreal forest areas. Roads have been constructed to move materials to and from these sites.

Human Impact on Boreal ForestsMining in BC and Alberta has led to road development and the clearing of mining sites in Canada’s Boreal Forest biome. Teck company operates the Elkview coal mine facility in Sparwood BC. BC has Canada’s Third largest output of mined materials.

End of Presentation

AA