Name ________________________________
Period _______
Chapter 7: Food and Agriculture
Read pages 158-165 in your text
Soil is a Living Resource
1. What are the three main components of soil?
2. What is the range in time it can take to build a few millimeters of soil?
3. In the best circumstances, how long does topsoil accumulate per year?
4. Describe the appearance of soil rich in nutrients.
5. What are the soil roles of each type of organism:
Bacteria, algae, fungi
Worms
6. What are the three factors that determine the health of the soil?
7. Where is the best farming soil located in the USA?
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8. Describe each of the soil horizons:
O
A
E
B
C
9. Which horizon does most of our food come from?
10. How deep is horizon A?
Ways we use and abuse soil
1. How much of the earth’s land is currently in agriculture production?
2. How many acres of cropland are ruined by erosion every year?
3. Erosion causes loss of land fertility. How do the sediments transplanted through
erosion affect bodies of water?
4. What is the relationship between the rate soil is being lost to the rate soil is
being replaced?
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Other Agricultural Resources
1. How much of the Earth’s fresh water is used for irrigation?
2. Excessive irrigation not only waste water but can lead to waterlogging. What is
waterlogging?
3. What happens to plants when they are waterlogged?
4. What are the three most common nutrients in fertilizer?
5. How do minerals in fertilizer that is applied to soil end up in our fresh water
supply?
6. How far does the average food item in the American diet travel between the farm
that grew it and the person who consumes it?
7. What are pesticides?
8. How much of our current crop yield might be lost if we had not pesticides to
protect them?
9. Name two dangers of using pesticides.
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10. Compare the amount of pesticide residue found on conventionally grown foods and
organic foods.
From Notes
1. What are the three non- organic components that make up soil?
2. Rank these components from largest to smallest.
3. What are two organic components of soil?
4. What is the most important factor that determines which component of soil will
have a high water holding capacity?
5. Which soil component has the highest water holding capacity?
6. Which soil component has the lowest water holding capacity?
7. When soil has a high infiltration rate, what is likely to be removed from the soil?
8. Which soil component has the highest infiltration rate?
9. Which soil component has the lowest infiltration rate?
10. What occurs when a soil has a high infiltration rate and a high capillary rate?
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11. What occurs when a soil has a low infiltration rate and a high capillary rate?
12. Why can’t soils with a very low ion exchange capacity absorb nutrients?
13. What is the optimal pH for soils?
14. What helps keep soil pH higher?
15. Name two causes of soil depletion in soils.
16. What occurs when soil pH becomes too low?
Why is this bad for the soil?
17. What two negative effects occur when soil permeability is very high?
18. Name five ways soil is degraded.
19. Describe two problems with using fertilizers.
20. What is the main effect of deforestation?
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21. Where do the soil particles end up as a result of erosion after decomposition?
Matching
A. crop rotation
F. Irrigation
K. deforestation
B. composting
G. no-till agriculture
L. Ion exchange capacity
C. salinization
H. Infiltration Rate
M. shelter belts
D. over cultivation
I. contour-strip cropping
N. overgrazing
E. water holding capacity
J. Capillary Action
O. Soil Permeability
1. _______Strong attraction between water molecules and soil causes water to be
drawn upward from the water table
2. _______What is the name of the process that produces soil in controlled
conditions?
3. _______What term is defined at the gravitational flow through soil?
4. _______The measure of +/- sites in soil where ions can bond.
5. _______Macronutrients that plants get from soil
6. _______The measure of how fast water passes through the soil
7. _______frequent plowing
8. _______alternating the type of crops grown
9. _______weed control, planting, and covering up all at once (low-till farming—
decrease the amount of tilling)
10. _______cultivation along sloping ground
11. _______ “belts” of trees planted around farmland to reduce wind erosion
12. _______depletion of forest land
13. _______animals stripping vegetation at a rate too fast for natural growth
patterns to counteract it
14. _______controlled introduction of water to an area
15. _______salts accumulating in and on the soil, hindering plant growth
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Use the soil Analysis Chart to determine the type of soil for each example below:
40% sand, 30% silt, 30% clay
______________
10% sand, 60% silt, 30% clay
______________
80% sand, 10% silt, 10% clay
______________
60% sand, 10% silt, 30% clay
______________
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