The Boreal Coniferous Forest Biome: The Boreal Coniferous Forest Biome Chapter 9


Name Origination: Name Origination Boreal – northern Coniferous – cone-bearing Taiga – Name given to boreal forest by Soviets meaning “swamp forest”


Abiotic Factors: Abiotic Factors Climate – Temperature range: -30oC to 20oC Precipitation range: 50 to 125 cm, mostly from summer rain Growing season is 60 days to the north of biome to 150 days in south of biome


Slide5: Light Summer days are shorter but warmer and brighter than further north


Slide6: Soil Permafrost thaws in spring and summer Glaciers helped form the many depressions that contain water forming lakes, swamps, and bogs Trees are acidic, making water runoff acidic, and therefore soil acidic


Slide7: Glacier movement prevented effective drainage, trapping water in soil Partly decayed organic matter accumulates as peat Peat is also known as sphagnum moss Nutrient poor topsoil is called podsol, Russian for “ashes”


Slide8: Glacier with stream formation due to retreat Podsol  Peat cut for fuel


Biotic Factors: Vegetation: Biotic Factors: Vegetation Coniferous trees, or conifers Dominate the boreal forest All but one are evergreen, which means they keep their needles (leaves) during winter Conifers do drop their needles, but only a few at a time all year Grow new needles every spring


Slide10: Dominant tree species: white and black spruce


Slide11: Deadfalls: fallen trees in boreal forest


Slide12: Tree Species in the Boreal Forest Northern Section: From Alaska to Newfoundland: dominant species are black spruce, white spruce and balsam fir. Tamarack is found in moist areas.


Slide13: North-East United States: From Adirondacks and White Mountains: same as northern section Great Lakes Region: Dominant species red pine, white pine, eastern hemlock, and white cedar Peaks of southern Appalachians: Dominant species are Fraser fir and red spruce


Slide16: St. Lawrence River valley and Maritime provinces: Dominate species is red spruce


Slide17: Dry and Burned Areas of Boreal Forest: Dominate species is Jack pine, due to the structure of its cone Cone will not open to release seeds until after forest fire Seeds germinate and colonize, therefore it is a fire successional species


Slide18: Certain deciduous trees also invade these areas that are burned: White birch, poplars, and alders Hardwoods are also common in moist soil of riverbanks and wet valleys


Slide20: Adaptations of Conifers Plants of boreal forest must cope with poor soil, low temperatures, and limited precipitation Soil contains enough moisture, but is frozen during majority of year Humidity is low, so not much moisture from air Vegetation must be able to tolerate long, dormant periods when water is unavailable


Slide21: Adaptations of Conifers Needles, instead of leaves, to reduce loss of water by evaporation Cuticle layer, waxy surface that reduces water loss Stomata located in groove on the underside of the needles


Slide23: Adaptations of Conifers Slope and structure of trees are ideal for harsh winters. Needles also do not allow snow to accumulate Branches are flexible to allow bending when snow builds up, however, freezing rain and wet snow can cling to needles and branches causing damage


Slide24: Adaptations of Conifers Needles contain high resin content, as well as thick cuticles which help resist action of decomposers. Needles decay slower. They also are always ready to photosynthesize when conditions are optimal


Slide25: Adaptations of Conifers Resin also helps to heal damaged bark by quickly covering wounds to prevent attack by bacteria and fungi


Slide27: Other Vegetation in the Boreal Forest Ferns and mosses live on the floor of the forest in the low light conditions Sphagnum moss grows abundantly in the acidic soil of the forest Lichens are also found in boreal forest, sometimes in great hanging masses on the trees, rocks, and among the mosses


Slide28: Wintergreen, bunchberry, and blueberry are common flowering plants that love shade and acidic soil All produce berries, important food for birds and mammals Fungi and mushrooms are common decomposers found in the boreal forest


Slide29: Ferns Moss Lichens Wintergreen Bunchberry Blueberry


Biotic Factors: Animals: Biotic Factors: Animals Hare, Lynx, and Wolverine Snowshoe hare is a key to boreal forest food web Lynx are dependent on the hare Wolverine is also a predator of the hare


Slide32: Wolverine Another predator of the snowshoe hare Fastest mammal in forest during winter Spreading toes let them chase prey over deep snow without sinking


Slide33: Moose Wade through wetlands and snow on stilt-like legs Solitary, but in winter gather together that trample snow into “yards” to help reach tree shoots, twigs, and brushwood below Pack snow into mounds to reach twigs on branches up higher


Slide34: Grown moose must eat 3600 – 4500 kg of vegetation to survive winter In spring, quite thin, but gain weight quickly


Slide35: Timber Wolf or gray wolf Moose predator Ranges over 100 km2 One of the most persecuted animals, for no real reason Childhood stories Livestock killed Hunt same animals as humans


Slide36: In plant undergrowth between snow and soil, a microclimate is created for small herbivores such as: Lemmings Voles These feed on grasses, mosses, herbs, and bark of shrubs and saplings Shrews Red squirrels feed on conifer seeds or conifer buds (they can seriously affect growth of these trees)


Slide37: Lemmings


Slide38: Voles Shrew


Slide40: Porcupine Roll up into a large black ball in upper branches of trees Nocturnal (active at night) Strong, curved claws help them to climb to upper branches Feed on small twigs, buds, and inner bark of trees Fear few predators due to their quills Wolverine have learned to roll them over and attack the belly Love salt, so can be found licking salt from roadside where salt is used to melt ice on roads


Small Carnivores: Small Carnivores Weasel family members are the smaller carnivores of the boreal forest Included are: Minks Martens Weasels Wolverines


Slide43: They prey on rabbits, rodents, birds, and insects Short tailed weasel range over 350 km2 Wolverine is a scavenger, it will actually challenge bear or wolf for their kill, and win… Weasel family members do not hibernate Grow thick protective coat


Slide44: Short-tailed weasel Wolverine Weasel Ermine Marten Mink


Hibernating Mammals: Hibernating Mammals Woodchuck Also known as a ground hog or marmot Feeds during day on vegetation Dens in burrow Food for a wide variety of predators, when killed, their dens become home to other animals


Slide46: May sleep up to 8 months, where its metabolism slows down Heart rate, normally 200 beats/min, drops to 4-5 beats/min May only breathe 2x/min Stored body fat consumed very slowly, so body temperature drops If outside temperature drops too much, animal awakens to restore normal circulation


Slide47: Chipmunk Feeds on fruits, nuts, seeds, insects, and bulbs Prey for hawk, owl, and other mammalian predators Wake up at intervals to feed on stored nuts and seeds


Slide48: Bears Two species in forest Grizzly bears found in western regions of Alaska, Yukon, and Northwest Territories Black bear, more common and smallest of North America, lives in all parts of forest


Slide49: Classified as a carnivore, but really an omnivore since it eats berries, nuts, roots, and honey Eats animals, as well as insects and larva, and even dead animals


Slide50: Den under fallen trees, hollow logs and trees, and under overhanging boulders Semi-hibernate in winter in northern parts of range Body temperature drops only slightly Breathing rates decrease a little, so not true hibernator!


Insects: Insects Two main seasons Summer is short, but active with feeding and breeding Winter is long, so dormant living as pupa or larva in bark crevices and soil


Slide52: Blood sucking insects: Black Flies Mosquitoes Deer Flies Deer Flies Mosquitoes Black Flies


Slide53: Tree-destroying insects: Spruce Budworm Larch Sawfly Spruce Budworm Larch Sawfly


Birds: Birds Insect-eating: Warblers Woodpeckers Chickadees Warbler Woodpecker Chickadee


Slide55: Conifer seed- and needle-eating: Evening grosbeak Red crossbill Blue grouse Spruce grouse Blue Grouse Spruce Grouse Evening Grosbeak


Slide56: Birds of prey: Owls Hawks Falcons Ospreys Eagles Falcon Osprey Owl Hawk Eagle


Human Impact: Human Impact Importance factors include: Firewood Lumber Pulpwood Foods: fruits, nuts, and sugars Prevent soil erosion Clean water Affect climate of region and world


Slide58: Economic importance factors: Forest industry Loggers Sawmill workers Pulp and paper workers Trade industry Newspaper workers Home builders Furniture builders


Slide59: Present condition of boreal forest Over exploitation and improper management are a problem 1 in 12 cut trees are used, rest left to rot Fire destroys 6x more forest than loggers Acid rain also affects trees


Slide60: What can be done? Integrated pest management Sustained yield forest management Controlled burns and cutting Development of resistant tree species Biological controls recycle