Module 4: Principles of Soil Quality 1

Question 1

what is soil?

Answer 1

A natural body that occurs on the land surface
Comprised of solids, liquids, and gasses
Characterized by one or both of the following
The ability to support rooted plants in a natural environment
Horizons or layers that are distinguishable from the initial material as a result of the interaction of the 5 soil forming factors

Question 2

what are the 5 soil forming factors?

Answer 2

parent material
climate
vegetation
time
topography

Question 3

how is parent material formed?

Answer 3

• rocks and minerals or organic biomass
• soil made through weathering or through decomposition of organic materials

Question 4

what is soil a source of?

Answer 4

nutrients and water

Question 5

what are practical application of soil information?

Answer 5

Nutrients
Water
Wetlands
Planning

Question 6

what are soil properties and types?

Answer 6

Texture, depth, and slope

Question 7

what determines high soil quality?

Answer 7

Level slope
Organic matter
Texture
Deep soil

Question 8

what are the soil components?

Answer 8

Sand silt and clay
Soil organic matter

Question 9

sand particle size

Answer 9

2.0 to .05 mm

Question 10

clay particle size

Answer 10

less than .002 mm

Question 11

silt particle size

Answer 11

.05 to .002 mm

Question 12

what does soil texture determine?

Answer 12

pore space and pore space holds air and water for plants and microbes in the soil

Question 13

sand grains

Answer 13

have larger particles and larger pores (macropores) between grains

Question 14

clay grains

Answer 14

have smaller particles and more micropores between grains

Question 15

water holding capacity of sand, silt, and clay

Answer 15

low
medium to high
high

Question 16

internal draining of sand, silt, and clay

Answer 16

high
slow to medium
very slow

Question 17

aeration of sand, silt, and clay

Answer 17

good
medium
poor

Question 18

ability to store plant nutrients in sand, silt, and clay

Answer 18

poor
medium to high
high

Question 19

cation exchange capacity

Answer 19

That’s the ability of a soil to deliver important ions, important nutrients to the root itself.

Question 20

what properties are key to identifying different soil types and how well those types support plant growth?

Answer 20

soil porosity, texture, and CEC

Question 21

Soil texture and organic matter determine what?

Answer 21

the porosity, water holding
capacity, and nutrient holding capacity of a soil type.

Question 22

soil particle size distribution

Answer 22

The soil particle size distribution of sand, silt, and clay determines soil texture

Question 23

what is ideal soil for growing crops?

Answer 23

mix of large and small pores. Typical to
that found in a loam soil. During a rain or irrigation event, this allows for infiltration of water
through the large pores.

Question 24

what are the 4 primary soil science specializations?

Answer 24

soil chemistry, soil physics, soil microbiology, and soil pedology

Question 25

what is soil according to the USDA?

Answer 25

a natural body on the surface of the earth consisting
of unconsolidated inorganic and organic
material whose characteristics depend on
the five soil forming factors.

Question 26

what are the 4 interactors in soil?

Answer 26

minerals (inorganic), organic
matter (living and dead), water, and air.

Question 27

CEC for sand

Answer 27

1

Question 28

CEC for silt

Answer 28

5-10

Question 29

CEC for clay

Answer 29

100-150

Question 30

humus

Answer 30

When microorganisms decompose organic matter, they produce a complex, dark brown,
colloidal organic material

Question 31

Trained soil scientists can predict soil type on a landscape using their knowledge of

Answer 31

horizon properties and also use understanding of 5 soil forming factors for why there are different textures and colors .