3. The taiga can be found in areas in the
Northern Hemisphere
4. Largest vegetation on earth
Taiga is the Russian word for forest
Belt of coniferous forest
Located in high latitudes of the northern
hemisphere
Sunlight hits the surface of the earth and scatters
Results to large temperature differences as seasons
progresses
Covers 11% of the earth’s terrestrial surface
5. What is Ecotone?
An ecotone is a transition area between two
biomes but different patches of the landscape,
such as forest and grassland
6. 4 major vegetation zones
Forest tundra ecotone
Open stands of spruce lichens and moss
Open boreal woodland
Lichens and black spruce
Main boreal forest
Continuous strand of spruce
Pines
Boreal mixed forest ecotone
Boreal forest grades into mixed forest
12. Summer
Strong
seasonal variation
Summers are short, cool and moist
(24-hr average temp is 10 °C or more) lasts 1–3
months and always less than 4 months.
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.
Influenced by northern hemisphere location
13.
14. Winter
Winters are prolonged, harsh and dry w/ long lasting
snowfall
The winter temperature range is -54 to -1° C (-65
to 30° F).
15.
16. 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.
17. Permafrost
Perenially
frozen subsurface that may be
hundreds of meters deep
Upper layer thaw in summer
Refreezes in winter
Develops when ground temp is below O˚C
18.
19.
20. Impervious to water
Waterremains and moves above it
Ground thus stays soggy even though precipitation is
low
This enables plants to exist
Accumulated organic matter protect the
permafrost
Shading and insulation
Reduces warming and retard thawing of the soil in
summer
23. The type of soil is called Pozol
are the typical soils of coniferous, or boreal
forests
sandy and excessively drained
poor soils for agriculture
Taiga soil tends to be young and poor in
nutrients.
It lacks the deep, organically enriched profile
present in temperate deciduous forests.
24. Since the soil is acidic due to the falling pine
needles, the forest floor has only lichens and
some mosses growing on it.
25.
26. Effect of permafrost to soil
Vegetationand organic debris impede the thawing of
the permafrost and act to conserve it
Permafrost chills the soil
Retarding the growth of both above ground and below
ground parts of plants
Limits activity of soil microorganisms
Diminishes aeration and nutrient content of soil
The colder the soil becomes, the closer to the surface
the permafrost moves, and the more shallow the soil
becomes
27. The effect becomes more pronounced the closer the
permafrost is to the surface of the soil
This contributes to the formation of shallow root
systems by plants
This is in order to get more water from the surface
28. Lichens retain soil moisture through the
growing season, encouraging the growth of
trees on sites that would otherwise be too dry.
30. Decomposition
Because of cool temperatures decomposition
is slow in the taiga.
Undecayed vegetation builds up on the forest
floor, making it feel like a sponge.
Since decomposition is slow, the soil is thin
and lacking in nutrients.
Trees grow taller where warmer temperatures
allow for faster decomposition or by streams
and rivers which carry nutrients from higher
ground.
32. Fires are reoccurring events in the taiga
During periods of drought, fires can sweep
over hundreds of thousands of hectares.
All boreal species, both broadleaf trees and
conifers are well adapted to fire
Unless too severe, fire provides a seedbed for
regeneration of trees
33.
34.
35. The Taiga appears as an endless sweep of
sameness – a blanket of spire-shaped
evergreens over the landscape.
The boreal forest conifers fall into 3 growth
forms (1) the spire-shaped spruces and fir.
(2) The open, thin, light-penetrating upper
canopy of pines and (3) the deciduous larch.
36. Only a thick carpet of mosses
grows in the dense shade of
spruce, while lichens grow
under pine.
37. Conifers are well suited to
the cold taiga environment.
The narrow, needlelike leaves
with their thickened cuticles
and sunken stomata reduce
transpiration and assist in
moisture conservation during
periods of summer drought
and winter freeze.
38. The dark green color of spruce
and fir needles helps the
foliage absorb maximum heat
from the sun and begin
photosynthesis as early as
possible.
Conical shape - promotes shedding of
snow and prevents loss of branches.
Evergreen habit - retention of foliage
allows plants to photosynthesize as soon
as temperatures permit in spring, rather
than having to waste time in the short
growing season merely growing leaves.
39. Black spruce (ability to tolerate
wet soils and occupies
cold, north-facing slopes and
bottomlands)
White Spruce and Birch
grow on permafrost-free
south-facing slopes.
40. For some species, wildfires (with return
times of between 20–200 years) are a
necessary part of the life cycle in the
taiga; some, e.g. Jack Pine have cones
which only open to release their seed
after a fire, dispersing their seeds onto
the newly cleared ground.
42. Insects play a critical role
as pollinators, decomposers, and as a part of
the food web.
Many nesting birds rely on them for food.
BIRDS
More than 300 species of birds have
their nesting grounds in the taiga. Siberian
Thrush, White-throated Sparrow, and Black-
throated Green Warbler migrate to
this habitat to take advantage of the long
summer days and abundance of insects found
around the numerous bogs and lakes.
43. Siberian Thrush
Black-throated Green Warbler
White-throated sparrow
44. Birds also feed and extract conifer
seeds from cones, thus helping in
the dispersal of seeds of trees.
45. The Taiga is home to a number of
large Herbivorous mammals, such
as moose and reindeer/caribou. Some areas of the more
southern closed boreal forest also have populations of other
deer species such as the elk (wapiti) and roe deer.