Chapter 4

Question 1

Why does agricultural diversity matter?

Answer 1

Cost-effective pest and disease management
Options to manage climate risks
Contributes to health and nutrition
Plays a role in sustaining soil health and habitats for important pollinators

Question 2

How are people casual agents?

Answer 2

Population pressures

Poor management of agricultural land

Question 3

When is land considered degradated?

Answer 3

When it’s productivity is diminished

Question 4

What effects does degradation have on soil?

Answer 4

Soil erosion (serious)
Decreased soil fertility
Contamination (e.g. pesticides)
Salinization

Question 5

What effects by does degradation have on land?

Answer 5

Overgrazing by livestock

Deforestation/Desertification

Question 6

What happens when geological erosion occurs?

Answer 6

Geological erosion is a natural leveling process

New soil forms faster than old soil can be removed

Question 7

What is accelerated erosion?

Answer 7

Erosion caused by water or wind

Question 8

Which type of erosion is more destructive?

Answer 8

Accelerated erosion

10 to 100 times more destructive than geological erosion

Question 9

What are some on-site effects of erosion?

Answer 9

Loss of topsoil

Washing away of seeds

Question 10

What are some off-site effects of erosion?

Answer 10

Sediment damage to water

Windblown dust

Question 11

What is the Universal soil loss equation?

Answer 11

A = Rainfall erosivity + Soil erodibility + Topographic Factor +Cover and management + erosion control practices
A = RKLSCP

Question 12

What are riparian buffer strips?

Answer 12

Natural or planted species along the bank of a stream or lake, reduces water velocity(erosion)

Question 13

Name 3 Best Management Practices

Answer 13

Conservation Tillage
Riparian Buffer Strips
Cover crops and mulch

Question 14

What are some soil conservation practices?

Answer 14

Contour farming
Contour buffer strips
Terrances
Contour stripping

Question 15

Name 3 factors that affect wind erosion

Answer 15

Wind velocity and turbulence
Soil surface conditions 
Roughness
Moisture content
Aggregate stability
Texture
Vegetation

Question 16

What are some wind erosion control measures?

Answer 16

Soil moisture control
Conservation tillage
Barriers (windbreaks, grasses, fences)

Question 17

How much of the Earth’s water is freshwater?

Answer 17

3%

Question 18

Define eutrophication

Answer 18

Enrichment of water with nutrients

This happens when fertilizers end up in the water supply

Question 19

Define anoxia

Answer 19

Absence of oxygen

Question 20

What are the most important limiting nutrients for aquatic systems?

Answer 20

Nitrogen and Phosphorous

Question 21

What is the cause of an ocean dead zone?

Answer 21

When the algae die their decay consumes a large amount of oxygen from the water and this leads to oxygen depletion or anoxia

Question 22

What is a leading contributor to reduced water quality

Answer 22

soil erosion

Question 23

What is the grasshopper effect?

Answer 23

Volatile substances move north by a series of ops

Multiple cycles of evaporation and condensation

Question 24

What characteristics should the ideal pesticide have?

Answer 24

• Selective
• Biodegradable
• Non-persistent
• Non-mobile

Question 25

Name 6 Greenhouse gasses.

Answer 25

``` Carbon dioxide Methane Nitrous Oxide Water Chlorofluocarbons Ozone ```

Question 26

What do GHG's do?

Answer 26

Absorb outgoing infrared radiation and warm the atmosphere

Question 27

What are some positive impacts of climate change on agriculture?

Answer 27

Increased productivity Possibility of growing new crops Larger growing seasons Decreased moisture stress

Question 28

What are some negative impacts of climate change on agriculture?

Answer 28

Increased insect infections Crop damage from extreme heat Planning problems due to less reliable forecasts Increased soil erosion Decreased herbicide and pesticide efficiency Increased moisture stress

Question 29

Greenhouse gas emissions per kg of food are highest for:

Answer 29

Lamb

Question 30

This gas is NOT a greenhouse gas but it negatively affects air quality and is particularly associated with agriculture:

Answer 30

NH3

Question 31

More than half of the total emissions of this greenhouse gas come from the agricultural sector:

Answer 31

N20

Question 32

Agricultural biodiversity is important because it can potentially provide farmers with a way to manage pests and diseases.

Answer 32

True

Question 33

In the Universal Soil Loss Equation, C is related to:

Answer 33

Crop Type

Question 34

In the Universal Soil Loss Equation, K is related to:

Answer 34

Soil organic matter

Question 35

Riparian buffer strips can lead to increased eutrophication problems

Answer 35

False

Question 36

The agricultural sector is the single largest contributor to total water USE in Canada.

Answer 36

False

Question 37

The process(es) by which pesticides end up in the far north is related to: a) Volatility of the pesticide b) Selectivity of the pesticide c) Mode of action of the pesticide d) Persistence of the pesticide e) Two of the above

Answer 37

E - two of the above

Question 38

Greenhouse gases absorb incoming short wave radiation from the sun.

Answer 38

False

Question 39

The earth would be _______________ without the presence of greenhouse gases in the atmosphere.

Answer 39

33oC colder

Question 40

The following is NOT considered to be a potential climate change impact to Canadian agriculture. a) Decreased productivity from enhanced CO2 b) Increased productivity from warmer temperatures c) Increased insect infestations d) Increased soil erosion e) Increased droughts

Answer 40

A - decreased productivity from enhance CO2

Question 41

Intraspecific biodiversity can help a crop withstand environmental pressures like drought or pests.

Answer 41

True

Question 42

Which of the following animal products consumes the most water (on a per pound basis)?

Answer 42

Beef

Question 43

This greenhouse gas is also responsible for destroying the ozone layer:

Answer 43

CFCs