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Taiga
Russian word for Forest
• largest biome in the world. It stretches over
Eurasia and North America.
• located near the top of the world, just below the
tundra biome.
• The winters in the taiga are very cold with only
snowfall. The summers are warm, rainy, and
humid.
• The taiga is also known as the boreal forest. Did
you know that Boreal was the Greek goddess of
the North Wind?
Location
The taiga is primarily a coniferous forest located
between 50 degrees latitude north and the Arctic
circle.
Human impacts
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forest fires
clear cutting
air pollution
poaching
……..are all major threats to the Siberian
Taiga and the Boreal forest.
Destruction of Taiga
• The taiga ecosystem is extremely sensitive to
disturbance with little ability to restore itself.
• Disruption of vegetative cover causes permafrost to
melt deeply, causing collapse of ground and loss of
soil.
• Automobile tracks cause deep gullies that persist for
years. The taiga wildlife is vulnerable to habitat
destruction, to overhunting, and to extinction
through loss of any of the animal or plant species
that make up the fragile, highly individual tundra
community of life.
Temperature
• The average temperature is below freezing
for six months out of the year. The winter
temperature range is -54 to -1° C (-65 to 30°
F). The winters, as you can see, are really
cold, with lots of snow.
• Temperature range in the summer gets as
low as -7° C (20° F). The high in summer can
be 21° C (70° F). The summers are mostly
warm, rainy and humid. They are also very
short with about 50 to 100 frost free days.
Precipitation
• The total precipitation in a
year is 30 - 85 cm (12 - 33 in)
.
• The forms the precipitation
comes in are rain, snow and
dew.
• Most of the precipitation in the
taiga falls as rain in the
summer.
Seasons
• The main seasons in
the taiga are winter
and summer.
• The spring and
autumn are so short,
you hardly know they
exist.
• It is either hot and
humid or very cold in
the taiga.
Soil/Land Formation
• similar to that of the tundra's.
• some parts of the taiga have
permafrost. Water from precipitation
and melting snow in warmer seasons
cannot seep through the permafrost,
so the taiga ground remains soft and
damp in some parts.
• Other areas that do not have
permafrost (like the Canadian shield in
North America) have a layer of hard
rock that remains close to the surface.
This dense rock prevents water from
escaping the surface and, therefore,
leaves the soil soggy in the spring and
summer seasons
Subclimaxes
• bogs (muskeg) occur in poorly drained, glacial depressions.
Sphagnum moss forms a spongy mat over ponded water. Growing
on this mat are species of the tundra such as cottongrass and
shrubs of the heath family. Black spruce and larch ring the edge.
• Pine forests, in North America dominated by the jack pine (Pinus
banksiana), occur on sandy outwash plains and former dune areas.
These are low nutrient, droughty substrates not tolerated by spruce
and fir.
• Larch forests claim the thin, waterlogged substrate in level areas
underlain with permafrost. These forests are open with understories
of shrubs, mosses and lichens. In Alaska stands of Larix larichina
are localized phenomena, but in Siberia east of the Yenesei River
the extreme continentality and nearly continuous permafrost give
rise to vast areas dominated by Larix dihurica.
Latitudinal Zones within the forest
running north to south - ecotone
• an open coniferous forest (the section most
properly called taiga)
• the characteristic closed-canopy needleleaf
evergreen boreal forest
• a mixed needleleaf evergreen-broadleaf
deciduous forest, the ecotone with the
Temperate Broadleaf Deciduous Forest.
• In the US, this southern ecotone is dominated by
white pine (Pinus strobus), sugar maple (Acer
saccharum), and American beech (Fagus
americanus).
Trees
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Balsam Fir
Black Spruce
Douglas-fir
Eastern Red Cedar
Jack Pine
Paper Birch
Siberian Spruce
White Fir
White Poplar
White Spruce
Fall in the Taiga
Wildfires
• The taiga is susceptible to many wildfires.
• Trees have adapted by growing thick bark.
The fires will burn away the upper canopy
of the trees and let sunlight reach the
ground. New plants will grow and provide
food for animals that once could not live
there because there were only evergreen
trees.
Needleleaf
Waxy coatings on needles
prevents moisture from
evaporating in drying winds.
It also allows the tree to survive
during hard hitting winter droughts,
and prevent snow from collecting
on them, which may cause the
branches to break.
Low Bio Diversity
• Evergreen trees reign supreme -- miles upon miles of the
exact same species are tree is often the case in the
taiga.
• Most trees in this biome tend to grow in dense patches
of one or a few species. Spruce, hemlock and fir are the
primary trees of the taiga.
• There are a few broad leaf trees in the taiga: birch,
poplar, and aspen. These species lose their leaves in the
fall. By shedding their leaves, these deciduous trees
save energy during the winter months. But in the spring,
these trees have to grow back new leaves.
• In contrast, evergreen trees do not have to regrow
leaves in the spring. However, they risk a chance of
breakage from heavy snow falls.
Animals
• Animals of the taiga tend
to be predators like the
lynx and members of the
weasel family like
wolverines, bobcat, minks
and ermine.
• They hunt herbivores like
snowshoe rabbits, red
squirrels and voles.
Animals
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American Black Bear
Bald Eagle
Bobcat
Canadian Lynx
Gray Wolf
Grizzly Bear
Long-Eared Owl
Red Fox
River Otter
Snowshoe Rabbit
Wolverine
Birds of the Taiga
• Many insect eating
birds come to the
taiga to breed. They
leave when the
breeding season is
over.
• Seed eaters like
finches and sparrows,
and omnivorous birds
like crows stay all
year long
• Red deer, elk, and
moose can be found
in regions of the taiga
where more
deciduous trees grow.
•
Caribou & Reindeer
• Once divided into several species, all caribou and reindeer,
including the domesticated reindeer, are now considered races of a
single species. The races vary in coloration from almost black to
brown, gray and almost white.
• The caribou is the only deer in which both sexes have antlers,
although those of the female are smaller.The antlers are unique in
that the lowest, forward-pointing tine is itself branched.
• Females are gregarious and gather in herds with their young, but
adult males are often solitary. In autumn, males fight to gather
harems of 5 to 40 or so females. The female produces 1,
occasionally 2, young after a gestation of about 240 days. Young
caribou are able to run with the herd within a few hours of birth.
• Some populations migrate hundreds of miles between their
breeding grounds on the tundra and winter feeding grounds farther
south. Grass and other tundra plants are their main food in summer,
but in winter caribou feed mainly on lichens, scraping away the
snow with their hoofs to expose the plants.
Adaptations
Some animals have structural adaptations
that help them survive in the taiga.
• The Canada lynx's wide paws work
like snowshoes. They distribute the
lynx's weight, and help it move in the
snow.
• Grizzly bears avoid the coldest
weather by going into their dens in the
fall and staying there until the early
spring. They have a protective layer of
fat that allows them to stay in their
dens while the weather is cold. They
don't hibernate but just sleep lightly
and stay out of the cold!
Tree Adaptations
• Evergreen trees are cone-shaped to help snow
slide off them so the branches won't break.
• The leaves or needles of evergreen trees lose
less water than other kinds of leaves. This also
helps them survive.
• Some broad-leaved trees like birch and aspen
have adapted to the taiga, too. Both trees are
very flexible and don't break easily when
covered with ice and snow!
Tiaga Plants
• The taiga landscape is a
stark and barren place. The
plants growing in the tundra
are often small and grow
close to the ground
• During the short-growing
season in the summer, the
taiga blooms with a variety of
low-growing plants. So what
plant life is found there?
Taiga Plant Adaptations
• Where soil accumulates in pockets or
cracks in rocks, small shrubs may grow.
• The taiga landscape is often covered with
rocks. The constant freezing and thawing
in the tundra helps to break the rocks into
smaller pieces.
Lichens
• Growing on the surface of this
rock is a lichen. Lichens are
unusual organisms that often
grow on exposed rock
surfaces. They are composed
of a fungus and an algae
living and growing together.
There are several varieties of
lichen, and in the autumn
lichen turn various colors.
• Lichen is the favorite food of
caribou and musk oxen.
Taiga Plant Adaptation
• Many plants, such as
this one, have leaves
that are dark red.
Dark leaves allow the
plant to absorb more
heat from the sun in
the cold taiga climate
Cushion Plants
• Many taiga plants, such
as this one, are called
cushion plants. That
means they grow in a
low, tight clump and look
like a little cushion.
Cushion plants are more
common in the taiga
where their growth habit
helps protect them from
the cold.
Coevolution
• Taiga birds help
distribute seeds.
When they eat
brightly colored
berries, the birds
carry seeds to other
places and leave the
seeds to grow.
Aurora Borealis
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The aurora borealis has fascinated, and often
terrified, humans for thousands of years. The people of
the north who saw the aurora frequently developed many
legends and stories about it, while those who lived
further south and rarely saw the aurora thought it was a
supernatural omen of war or destruction.
• As people began to seek more natural explanations for
the aurora, they came up with many theories: reflected
firelight from the edge of the world, sunlight reflected
from the arctic ice, or maybe reflected by ice crystals
high in the sky. It wasn't until the 20th century that
people finally began to make headway in the study of the
aurora, and there are still many unanswered questions
about it.
Extreme Climate Dangerous
• The taiga has a very extreme climate. The intense cold presents
many problems if you are not prepared.
• In any situation where extreme cold is present, hypothermia is
a risk you take. Hypothermia is the lowering of the body's core
temperature.
• There are two types of hypothermia, acute and chronic. Acute
hypothermia is the rapid lowering of the body's core
temperature. Chronic hypothermia is the slow lowering of the
body's core temperature. If the temperature drop occurs in less
than four hours it is acute, otherwise it is chronic. Acute
hypothermia is also called immersion hypothermia and
typically occurs when a person is in cold water.
• Hypothermia is considered severe when the body's core
temperature drops below 90 degrees F, and mild from normal
body temperature to 90 degrees F.
Frostbite
• Frostbite is caused by exposure to severe
cold. Frostbite occurs more often when the
wind is blowing, quickly taking heat from the
body. The ears, cheeks, nose, toes, and
fingers are frostbitten the most frequently.
When the part of the body is exposed to cold,
the blood vessels constrict. When this
occurs the blood supply to the chilled parts
decreases and the tissues don't get the
warmth they need.
True or False
• In Scandinavia and western Russia the
spruce and fir is a common tree.
• Although the taiga’s summer is plentiful,
some animals like wolves and caribou,
travel north to the tundra for the summer.
• The taiga’s temperatures can drop below
-60 F in the winter and jump above 104 F
in summer
Video results for taiga biome
• The Boreal Forest
Biome: Taiga Biome
3 min 14 sec - Sep 7, 2008
www.thewildclassroom.com
Taiga Links
• Blue Planet Biomes--Taiga - Good general taiga site
which includes location, climate, and detailed animal and
plant information.
• Taiga Biological Station - This Canadian site answers
the question "What is the taiga?" and provides a taiga
food web.
• Taiga Rescue Network - Along with nature and climate
information, this activist site includes information about
indigenous people, natural resources, and government
policies regarding the taiga. It also hosts a great taiga
photo gallery.
• Wild Places--Coniferous Forests - Good general site
made especially for kids.
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