Soil and Vegetation answers

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					                          Soil and Vegetation Connections
                                  Making Connections 2nd Ed. Page 170-171

Key Terms
Can be obtained through the textbook glossary

2. a) how is topsoil formed?

Topsoil is formed very slowly as dead plants, leaves, and animals are decomposed by bacteria. The
decaying organic materials form humus, which gives the topsoil its dark colour.

3. Why is the size of rock particles important to soil structure?

The larger rock particles of sand allow rainwater to drain quickly through the soil, while the smaller
particles of clay prevent rapid drainage. A well-balanced mixture of both allows the soil to hold
moisture, and at the same time allows water to pass through at a rate moderate enough to allow
plants to take up nutrients.

4. Explain the difference between leaching and calcification.

      Leaching occurs in areas of high precipitation (creating wet-climate soils); calcification occurs
       in dry climate areas (creating dry-climate soils).
    The leaching process is a downward movement of water through the soil; the calcification
       process is an upward movement of water through the soil.
    As leaching occurs, water dissolves the chemical nutrients and carries them downward; as
       calcification occurs, water evaporates, leaving behind the minerals that were dissolved in it.
    Leaching removes nutrients in the soil that plants need to survive; calcification builds up
       nutrients and minerals in the upper portion of the soil.
    Excessive leaching results in a poor, often thin, topsoil layer; excessive calcification results in a
       layer of mineral deposits that is poisonous to plants.
**Diagram was drawn on the board during the soil note.

6. There are two classes of trees. Which one can survive a harsher climate? Why?

Coniferous trees can survive in a harsher (colder) climate because they have the following
    Long roots are able to extract nutrients from the poor soil.
    Sticky sap prevents the needles from freezing.
    Waxy needles and thick bark prevent a loss of moisture in times of drought.
    The needles and flexible branches easily shed snow to prevent damage.
    The needles can conduct photosynthesis on warm days beyond the normal growing season.

7. Name the Canadian vegetation region which:

a) Is the largest                              Boreal and Taiga forest region
b) Is the smallest                             Deciduous forest region
c) Is the wettest                              West Coast forest region
d) Is the coldest                              Tundra region

8. Explain, in your own words, the term “transition zone.” Give an example and explain why this
vegetation region is a transition zone.

Transition zone:
    A transition zone is an area where the natural vegetation of one region gradually changes into
        the natural vegetation of another region.
    A transition zone is the line on a map that shows the boundary between one vegetation region
        and another, but does not indicate and abrupt change in the natural vegetation.
    A large transition zone is considered to be a vegetation region in itself.
    A transition zone is the area where the climate and soil conditions of one region begin to
        change into the climate and soil conditions of another region.

An example of a transition zone is the Mixed forest vegetation region. This region is located between
the Boreal and Taiga forest region and the Deciduous forest regions. The Mixed forest vegetation
region is a transition zone because it has the same type of natural vegetation, namely coniferous and
deciduous forests, as the two regions that border it. In the northern part of the region the climate is
similar to that of the Boreal and Taiga forest, while in the southern part of the region the climate is
similar to that of the Deciduous forest. The soil in northern parts of this transition zone is similar to
the leached, infertile soil of the Boreal and Taiga forest; in southern parts, it resembles the soil of the

12. “If you climb up a mountain, you will find a similar sequence of vegetation to that you would
find if you travelled from southern Canada to the high Arctic.” Explain why this is a valid statement.

As you climb up a mountain, the temperature decreases. With every increase in altitude, the air
becomes colder. The change in the mountains climate has a direct effect on the type of vegetation
growing up the mountainside. The warmer temperatures at the bottom encourage the growth of
deciduous and coniferous tress and the abundant groundcover in the form of grass, small plants, and
shrubs. Higher up, the deciduous trees start to disappear because they cannot survive the colder
temperatures. As the climate becomes even colder, the groundcover and shrubs begin to disappear.
The coniferous trees begin to thin out, and gradually disappear. All that remains is moss, and very
small plants growing between patches of bare rock. A snowcap sits on the very top of the mountain
all year.
         As you travel from southern Canada to the high Arctic, the climate becomes colder. It affects
the vegetation in the same way that an increasingly colder climate affects the vegetation growing up a
mountainside. The weather in the Southeastern climate region of southern Canada is warm and we,
and encourages the growth o deciduous and coniferous trees. The dry climate of the Prairies does
not encourage the growth of trees, but the grass grows abundantly. North of the Prairies, the Boreal
and Taiga forest region has climate conditions that are harsher than those in the Mixed forest and
Grassland regions. These conditions prevent deciduous trees from growing, but the coniferous trees
still survive. Farther north, where temperatures are even colder, the coniferous trees begin to thin
out, until they gradually disappear. Above the tree line is the Tundra where only small shrubs, moss,
and lichen grow close to the ground, between patches of bare rock. In Arctic areas of the Tundra,
there is nothing but snow and ice.
13. Complete the chart
Vegetation         Types of Natural             Temperature          Precipitation         Soil Characteristics
Region             Vegetation                   Characteristics      Characteristics
Tundra             -Shrubs, mosses, lichens,    -Cold, short         -Very little          -Thin soils,
                   small flowers                growing season       precipitation, most   permafrost
                                                                     areas les than
Boreal and Taiga   -Coniferous trees, e.g.      -Cold temps          -wet climate          -very little humus
Forest             white and black spruce,      -short growing                             -shallow topsoil
                   balsam fir, pine             season                                     -grey-coloured
                   (evergreens), which lose                                                topsoil
                   few needles                                                             -acidic
                   -Hardy deciduous trees                                                  -rainfall and
                   (poplar and white birch)                                                snowmelts wash
                   in southern portion                                                     away soluble
                                                                                           -leached soil
                                                                                           -infertile and
                                                                                           unsuitable for
                                                                                           -few organisms such
                                                                                           as bacteria and
Mixed Forest       -coniferous and              -temperate climate   -regular, abundant    -deep, grey-brown
                   deciduous trees (spruce,     has warm summers                           topsoil rich in
                   fir, pine, cedar, hemlock,   and cool winters                           minerals
                   maple, beech, ash, oak,      -cold winds create                         -good supply of
                   birch)                       a harsh climate                            humus
                   -small shrubs, e.g.          along the coast of                         -few soluble
                   junipers along the coast     the Maritime                               minerals are
                   of the Maritime              provinces                                  removed from
                   provinces                                                               topsoil by leaching
                                                                                           -suitable for farming
Deciduous Forest   -deciduous trees             -long, hot summers   -plentiful            -less acidic than
                   (especially hardwood         -minimum of five                           Mixed forest b/c of
                   trees such as maple,         months of warm                             greater number of
                   beech, hickory, ash, black   weather                                    deciduous tress
                   walnut)                      -relatively mild                           -more humus than
                                                winters                                    Mixed forest
                                                                                           -humus-rich topsoil
                                                                                           is dark brown
                                                                                           -some soluble
                                                                                           minerals leached
                                                                                           from topsoil by
                                                                                           abundant rain
                                                                                           -most fertile soil of
                                                                                           eastern Canada
Grassland          -drought-resistant short     -cold winters, hot   -very dry             -limited amount of
-short grass       grasses with root            summers              -limited rainfall     humus
                   systems which forms a                             -high evaporation     -calcified soils
                   sod mat                                                                 -unsuitable for crops
                   -sagebrush and cactus                                                   -suitable for grazing
                   -trembling aspen, willow,                                               cattle and other
                   and spruce grown only in                                                animals
                    river valleys where
                    enough moisture is

                    -long grass
                    -oil seeds
                                                                                                -large amounts of
-long grass                                      -cold winters, hot     -dry                    humus that result in
                                                 summers                -increased precip       rich black soil
                                                                        -just enough rainfall   -richest soil in
                                                                        to keep the minerals    Canada
                                                                        within easy reach of    -produces some of
                    -long grass dotted with                             the grass roots         the best grains in the
                    clumps of trees                                                             world
                    -coniferous trees more
                    common in the north                                 -more precip than       -transition soil
-parkland           -deciduous trees             -cold winters, hot     grassed area, but       between the rich
                    dominate in the south        summers                less than forested      black soil of long
                                                                        area                    grass and the grey-
                                                                                                coloured soil of the
                                                                                                Boreal forest
Cordilleran         -vegetation varies greatly   -warmer in the         -heavier rainfall on    -soils of all types
Vegetation          due to varying temps and     valleys than high in   the west side of        -soils change
                    precip                       the mountains          mountains               completely wihin a
                    -grasses and catuses in      -dry, hot valleys on   -drier on the east      short distance
                    dry, hot valleys on the      east side of           side of mountains       -soil type
                    east side of mountains       mountains              -heavier                determined by
                    -coniferous forests on       -temps get colder      precipitation on        elevation, slope,
                    lower slopes where           with elevation         lower slopes            rainfall, and veg
                    precipitation is heavier                            -snow and ice on the    cover
                    -meadows of flowers and                             very highest slopes     -in dry, hot valleys
                    shrubs similar to Tundra                                                    on east side of
                    veg on higher slopes                                                        mountains, soils are
                    above tree line                                                             similar to those in
                    -no veg on the very                                                         short grasslands
                    highest slopes                                                              -irrigation is often
                                                                                                required for
                                                                                                -grey-coloured soils
                                                                                                under coniferous
                                                                                                -tundra soils and
                                                                                                bare rock on higher
                                                                                                slopes above tree
West Coast Forest   -temperate rainforest        -mild climate          -heavy rainfall         -lush veg provides a
                    (lush forests of Douglas                                                    lot of plant material
                    fir, Sitka spruce, red                                                      to make humus
                    cedar, western hemlock)                                                     -minerals leached
                    -trees more than 1m in                                                      deep into the soil
                    diameter, and over 50m

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