Chapter 10- Agriculture Flashcards Preview

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Flashcards in Chapter 10- Agriculture Deck (40):
1

CLI

-canada land inventory
-wanted to figure our what resources we have and where they are
Looked at: agriculture land, forestry potential, wildlife, recreation
-quality rated accordingly

2

How much of Canada's land mass is agriculture land?

7%
40% of that is marginal or poorer quality
most in South where 90% of population lives
less than 2% is highest quality and we are building houses on this land

3

chernozenic soil

some of best agriculture soil
-building houses on it

4

Farming in Canada

1. Green Revolution
2. Biofuel revolution (corn and soy)
3. Livestock revolution (up production due to growth hormones)
4. Impact on the global landscape (clearing & massive machinery)

5

when did agriculture originate

- 9000 to 11000 years ago, shift in demographics with start of agriculture and then the industrial revolution

6

industrial revolution

-food production increased because 1 person could do the work of an entire family with machines

7

Agriculture induced changes and increased

-availability of food and feed
-sedentary lifestyles (food storage)
-permanent settlements
-food surpluses
-trade
-conflicts for land (war)
-global populations
-pollution

8

Green Revolution

worldwide intensification of production
-more output/unit area
-2x world grain production since 1961
-changed how farming is done

9

Green Revolution and the Enviro

-began in 1940s
-dramatic increase in yields
-selective breeding
-application of auxiliary energy inputs (use other types of energy to create food)
-mechanization of farming (machines)
-biocide applications (to kill pests)
-war pushed technology change

10

Auxiliary Energy Flows

2nd law of thermodynamics- loss of energy with longer food chains
-a means to counteract energy loss through the use of: fertilizers
-fossil fuels
0irrigation
0genetics
-biocides
all of these take energy

11

Agroecosystems

communities of living organisms and the physical resources that sustain them, managed to produce agricultural products
-different species live on agricultural land
-used to do more crop rotation
-monoculture ^risk of whole crop being whipped out
-10x more energy used for every 1unit of energy produced

12

Substinence Farming

-can produce 10 food units for every 1 unit of energy used

13

Sustainable Livlihoods

-each person grows their own food for them

14

GMOs

-to increase stalled yields in crop yields
-biotechnology & genetic manipulation
-can reduce the use of pesticides
-makes food different than the olden days

15

GMOs cautions and dangers

1. Pleiotrophic effects- unexpected side effects (potential changes in toxins or nutrient content, changes in our genetic makeup)
2. Enviro effects- interrupt insect pollination
-disrupt biogeochemical cycles, interbreed with wild relatives, create superweeds
3. Unintentional Spread- onto lands where they are not intended to grow
-lawsuits, problem with maintaining organic certification

16

Most Common GMOs

-soybeans
-corn
-cotton
-canola

17

Why is there still so much poverty?

agriculture gives us 94% of protein and 99% of calories but 20% of people are still malnourished and obesity has tripled
-Canada contributes to world food supply
-due to disproportionate sharing of resources

18

Effect of agriculture on aquatic ecosystems

1. Nutrient losses
2. Pesticide Losses
3. Sedimentation
4. Pathogens
5. Wetland drainage

19

Nutrient losses

Eutrophication- highly productive wetlands dying due to too many nutrients due to fertilizer run off
-can lose surface and ground water
-messes up biogeochemical cycles

20

Pesticide Losses

-some goes right up into atmosphere
-with wind they get carried away
-runoff and leeching
-goes into the soil
-carried into water bodies
-impacts species that live there

21

Sedimentation

pollution
-too much sediment can clog gills of fish and suffocate fish eggs
-caused by cattle getting too close to riverbeds

22

turbidity

foggy, mess up respiration

23

Pathogens

1. pollute drinking water when feces gets into ground water system
2. can come into crops by irrigation systems
3. contaminating shell fish that take in water

24

Wetland Drainage

lost 60-70% of wetlands in AB
-too full of nutrients (hypereutrophic)
-many dead wetlands modified by agriculture
-wetlands have a dynamic interface with ground water

25

Irrigation

largest global use of water
-used in BC to grow grapes and fruit (because the place used to be a desert)

26

Impact on terrestrial Ecosystems

1. Soil Quality
2. Biodiversity
3. Greenhouse Gases

27

Soil Quality

-soil blows away if there are not enough nutrients and moisture
-wind and water erosion take soil away
-need organic matter in soil to hold moisture and nutrients

28

Biodiversity

habitat loss
-plant monocultures
-range land grazing, cover grazing

29

Greenhouse gases

-affects global warming
-methane
-nitrous oxide (tailpipe fertilizers)

30

Salinization

excess salt in soil

31

desertification

degradation of dry land

32

contamination

herbicides, insecticides
still some DDT contamination

33

Types of Pesticides

1. Insecticide- kill insects (DDT, malathion, carbofuran)
2. Herbicides- kill weeds eg atrazine, 2, 4-D, roundup

34

Fungicides

hill fungi ex) methyl bromide

35

Ideal Pesticide

-kills only target species
-breaks down quick with no harm
-no genetic resistance
-cheaper than doing nothing

36

Benefits of Pesticides

1. ^ crop yields
2. saves lives (decrease malnutrition)
3. live longer ^human health
4. ^ profit
5. cheaper food cost
6. very efficient, works really fast

37

Pesticide use in the enviro

-genetic resistance
-killing non-target species
-persistence, mobility
-biomagnification
-human health

38

Alternatives to pesticides

-use better pesticide
-improve cultivation practices
-use natural enemies
-biological control
-birth control (genetically)
-spot spraying

39

Sustainable Answers

1. Integrated Pest Management- minimize yield losses from pests and minimize negative impacts of pest control
2. Integrated Plant Nutrient Systems- maximize nutrient use (recycle, N-fixers)
minimize nutrient loss (don't overtill soil)
-optimize productivity of nutrient flows
3. No-till conservation agriculture- sow directly (reduce soil impact, maintain permanent plant cover (absorb moisture reduce irrigation), rotate crops, higher yields=lower costs and labours)
4. Organic Farming- goals=biodiversity, soil, water, air, less energy, reduce pollution

40

Organic Farming

Methods- free range
Why grow- ethical, health reasons
Why buy- ethical, help, political, economic