Chapter 10- Agriculture Flashcards Preview

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

CLI

A

-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
Q

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

A

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
Q

chernozenic soil

A

some of best agriculture soil

-building houses on it

4
Q

Farming in Canada

A
  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
Q

when did agriculture originate

A
  • 9000 to 11000 years ago, shift in demographics with start of agriculture and then the industrial revolution
6
Q

industrial revolution

A

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

7
Q

Agriculture induced changes and increased

A
  • availability of food and feed
  • sedentary lifestyles (food storage)
  • permanent settlements
  • food surpluses
  • trade
  • conflicts for land (war)
  • global populations
  • pollution
8
Q

Green Revolution

A

worldwide intensification of production

  • more output/unit area
  • 2x world grain production since 1961
  • changed how farming is done
9
Q

Green Revolution and the Enviro

A
  • 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
Q

Auxiliary Energy Flows

A

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
Q

Agroecosystems

A

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
Q

Substinence Farming

A

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

13
Q

Sustainable Livlihoods

A

-each person grows their own food for them

14
Q

GMOs

A
  • to increase stalled yields in crop yields
  • biotechnology & genetic manipulation
  • can reduce the use of pesticides
  • makes food different than the olden days
15
Q

GMOs cautions and dangers

A
  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
Q

Most Common GMOs

A
  • soybeans
  • corn
  • cotton
  • canola
17
Q

Why is there still so much poverty?

A

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
Q

Effect of agriculture on aquatic ecosystems

A
  1. Nutrient losses
  2. Pesticide Losses
  3. Sedimentation
  4. Pathogens
  5. Wetland drainage
19
Q

Nutrient losses

A

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
Q

Pesticide Losses

A
  • 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
Q

Sedimentation

A

pollution

  • too much sediment can clog gills of fish and suffocate fish eggs
  • caused by cattle getting too close to riverbeds
22
Q

turbidity

A

foggy, mess up respiration

23
Q

Pathogens

A
  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
Q

Wetland Drainage

A

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
Q

Irrigation

A

largest global use of water

-used in BC to grow grapes and fruit (because the place used to be a desert)

26
Q

Impact on terrestrial Ecosystems

A
  1. Soil Quality
  2. Biodiversity
  3. Greenhouse Gases
27
Q

Soil Quality

A
  • 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
Q

Biodiversity

A

habitat loss

  • plant monocultures
  • range land grazing, cover grazing
29
Q

Greenhouse gases

A
  • affects global warming
  • methane
  • nitrous oxide (tailpipe fertilizers)
30
Q

Salinization

A

excess salt in soil

31
Q

desertification

A

degradation of dry land

32
Q

contamination

A

herbicides, insecticides

still some DDT contamination

33
Q

Types of Pesticides

A
  1. Insecticide- kill insects (DDT, malathion, carbofuran)

2. Herbicides- kill weeds eg atrazine, 2, 4-D, roundup

34
Q

Fungicides

A

hill fungi ex) methyl bromide

35
Q

Ideal Pesticide

A
  • kills only target species
  • breaks down quick with no harm
  • no genetic resistance
  • cheaper than doing nothing
36
Q

Benefits of Pesticides

A
  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
Q

Pesticide use in the enviro

A
  • genetic resistance
  • killing non-target species
  • persistence, mobility
  • biomagnification
  • human health
38
Q

Alternatives to pesticides

A
  • use better pesticide
  • improve cultivation practices
  • use natural enemies
  • biological control
  • birth control (genetically)
  • spot spraying
39
Q

Sustainable Answers

A
  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
Q

Organic Farming

A

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