Lecture 9- Boreal Forest Soil and Vegetation

Question 1

Soil characteristics affects _______ which are major determinants of the floristic community that will result

Answer 1

The soil moisture and nutrient stores

Question 2

What is soil parent material?

Answer 2

Rocks and sediments deposited from other areas, they weather and erode over time and develop soil

Question 3

The way the soil is _____ can change the type of soil

Answer 3

Deposited

Question 4

What is fluvial deposition?

Answer 4

Sediments deposited by flowing water

Question 5

What is Eolian deposition?

Answer 5

Sediments deposited by wind

Question 6

What is Lacustrine deposition?

Answer 6

Materials deposited in lakes

Question 7

What is Glacial Till deposition?

Answer 7

Sediments deposited by glacial ice

Question 8

Plant material influences ______

Answer 8

-Soil texture
-Mineralogy
-Buffering capacity

Question 9

How does the soil form?

Answer 9

Parent material accumulate

Question 10

Soil horizons are differentiated by ______

Answer 10

-Climate (wind, temperature, water)
-Biotic activities
-Topography

Question 11

Describe the four steps of soil formation

Answer 11

1.Weathering Begins (disintegrating rock)
2.Organic matter (parent material)
3.Mineral Fragments and organic matter (horizon A and C)
4.Greater plant growth (Horizon A, B and C)

Question 12

Soil texture directly impacts interactions with what?

Answer 12

Water and vegetation patterns (water holding capacity and soil drainage)

Question 13

What is the difference between large grain (sand) and small grain (clay)?

Answer 13

-Larger grain means more space between each grain = more water that can pass through = more rapidly draining.
-Clay is very tiny, not much space for water to pass through = more poorly drained

Question 14

What is field capacity?

Answer 14

The content of water remaining in a soil a few days after being wetted and free drainage nearly ends (how much water is still available for plants to take up after a few days, pressure gradient thats ideal for plants)

Question 15

What influences soil drainage (field capacity)?

Answer 15

-Grain size
-Water flow rate
-Ground water

Question 16

Soil drainage highly influences _____ and _____

Answer 16

-Vegetation type
-Plant community composition

Question 17

In general, conifers in ____ areas and deciduous in ____ areas

Answer 17

-Wet
-Dry

Question 18

What is soil horizons?

Answer 18

Separation of soil into distinct sections based on organic matter that has leached through or minerals available (layer of soil)

Question 19

Horizons have ______ produced by soil forming processes

Answer 19

Distinct characteristics

Question 20

What is horizon A?

Answer 20

A is considered mineral soil but can often have a lot of organic material in it that has leached in from the decomposing leaf litter

Question 21

What do you start to see in horizon B and C?

Answer 21

Where you start to see mineralization of the parent material

Question 22

Will all soils show differentiation? What does it depend on?

Answer 22

Not all soils will show this differentiation depends on how old the soil is and how much leaching and weathering has occurred

Question 23

Describe soil horizons of the tropics

Answer 23

-Fast decomposition, little hummus layer
-High soil microbial activity
-Small organic layer

Question 24

Describe soil horizons of the boreal

Answer 24

-Slow decomposition, accumulated humus layer
-Big organic layer

Question 25

Describe soil horizons for anaerobic soils

Answer 25

Rooting layer is predominantly poorly decomposed organic matter

Question 26

What are the six main soil types of the boreal forest?

Answer 26

1.Podzolic 2.Brunisolic 3.Luvisolic 4.Cryosolic 5.Gleysolic 6.Organic

Question 27

Describe Brunisolic soils

Answer 27

-Forested areas -Less horizon development (less weathering) -Formed under forests -Found under mixed wood forests -Cool and dry regions

Question 28

What tree type is found in brunisolic soils?

Answer 28

Mixedwood forests

Question 29

What is eutric brunisols?

Answer 29

Dominate calcareous deposits of cooler high and mid-boreal regions

Question 30

What is a melanic brunisols?

Answer 30

In milder moist climate of Southern Ontario low boreal (associated. with deciduous trees)

Question 31

Describe luvisolic soils

Answer 31

-Definition between A and B horizon -Found under mixedwood forests -Subhumid to humid forests -Cool and wet -High clay percentage -Formed by lacustrine deposits -Loam soil due to past glaciation leaving glacial silt and clay

Question 32

What type type is found on luvisolic soils?

Answer 32

Mixedwood forests

Question 33

Describe podzolic soils

Answer 33

-Red horizons due to high iron content (depends on the amount of leaching) -Coarse to medium textured -Dominated by conifers -Sandy parent material -Significant rainfall >700mm (lots of water flowing and weathering) -Low nutrient status

Question 34

What type of trees do you find on podzolic soils?

Answer 34

Coniferous forests

Question 35

Describe gleysolic soils

Answer 35

-Dominant wetland soil -Fluctuating water table and prolonged saturation -High water table reduces decomposition so would be a deep organic layer -Mottling -Large areas of poorly drained lowlands

Question 36

What is mottling?

Answer 36

Streaks of red iron in grey soil

Question 37

What is the difference between dry and wet gleysolic soils?

Answer 37

Dry- higher oxygen = iron oxidized Wet- low oxygen = iron reduced

Question 38

Describe organic soils

Answer 38

-Dominant soil of peatlands -Accumulation of poorly decomposed organic matter -Cold and wet -Underlain mineral soil often permafrost

Question 39

Describe cryosolic soils

Answer 39

-Where permafrost exists close to surface -North of treeline in subarctic forest, extends into boreal and alpine areas -More tundra soils -Organic peat develops on top -Cold and dry =Poor development of horizon

Question 40

The moisture type of lowland boreal forests soils is ______

Answer 40

Hydric or hygric

Question 41

Lowland boreal soils have _____ active layer and _____ organic layer

Answer 41

-Thin -Thick

Question 42

What type of soils would you find in lowland boreal forests?

Answer 42

Glysolic and organic soils

Question 43

Describe the water table and nutrient availability of lowland boreal soils

Answer 43

-Tolerant of low nutrient availability -High fluctuating water table (high water table reduces the active layer, changes in vegetation adapt to shallow roots and low nutrient)

Question 44

What type of trees would you find in lowland boreal soils?

Answer 44

Black spruce and tamarack

Question 45

The moisture type of midslope soils would be _______

Answer 45

Mesic

Question 46

Midslope boreal soils have _____ active layer and a ____ organic layer

Answer 46

-Medium -Medium

Question 47

What type of soils would you find in midslope boreal forests?

Answer 47

Luvisols and brunisols

Question 48

Describe the nutrient availability of midslope boreal soils

Answer 48

High nutrient availability for vegetation

Question 49

What type of trees would you find in midslope boreal forests?

Answer 49

White spruce, aspen, birch, balsam fir

Question 50

The moisture type of top slope boreal soils is ______

Answer 50

Xeric (dry)

Question 51

Top slope boreal soils have _____ active layers and _____ organic layer

Answer 51

-Thick -Thin

Question 52

What type of soils would you find in top slope boreals?

Answer 52

Podzols

Question 53

Describe the water table and nutrient availability of top slope boreal soils

Answer 53

-Trees adapted to low water availability -Low nutrient availability for vegetation

Question 54

What type of trees would you find in top slope boreal forests?

Answer 54

Jack pine