1. “This…is the world that has been pulled over your eyes to blind you
from the truth.“
- Morpheus, the Matrix (1999)
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2. Written by James Dauray
Textbooks used as reference:
 Living in the Environment by Miller
 Environmental Science by Cunningham & Cunningham
 More teaching resources and lectures available here:
www.docstoc.com/profile/jamesdauray
Last updated December 21, 2010
2

3.  Producing enough food has become a greater challenge
as the human population reaches 7 billion.
 Food energy is measured in calories.
 Undernutrition occurs when someone does not eat
enough calories.
 Adults need on average 1000 calories per day to simply survive.
 Average of 2100 calories needed for a normal, healthy life.
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4. 4

5.  Chronic Hunger and Food Security
 About 925 million people are considered chronically
undernourished or malnourished.
 Most of these are in developing countries.
 This is about 13% of the world’s population.
 Theoretically, there should be enough food to supply about
3000 kcal/day to everyone.
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6. 6
Source: Miller Environmental Science, 13th Edition

7.  Undernutrition – Insufficient caloric intake.
 Malnutrition - Nutritional imbalance caused by lack of
specific dietary components.
 Overnutrition – A daily intake of calories that is too
high, leading to obesity.
 The most common dietary problem in wealthy countries.
 Up to 64% of all adult Americans are overweight.
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9.  Iron deficiency is the most common dietary imbalance in
the world.
 Leads to anemia – insufficient oxygen transported to the
brain, muscles, and organs due to low red blood cell count.
 Symptoms include fatigue, dizziness, headache
 Increases risk of death in childbirth
 Good sources of iron: Red meat, eggs, beans, and some
green vegetables (spinach, broccoli)
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10.  Iodine deficiency is another very
common type of
malnutrition, especially in rural
developing areas.
 Iodine is required for production of
thyroid hormones, which control
the body’s rate of metabolism.
 Chronic lack of iodine can slow all
parts of normal
development, including body size
and brain function.
 Lack of iodine can also cause a
Source: Miller Environmental
goiter, or a swollen thyroid gland. Science, 13th Edition
 Good sources of iodine: seafood and
plant crops from iodine rich soils.
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11.  A famine is when large-scale undernourishment occurs
in a population.
 Most of the population is eating less than the daily
minimum calories needed (1000 calories)
 Drought causes more than half of famines.
 Other significant causes: war and bad governance.
 Ex: North Korea was reluctant to request foreign assistance after
severe flooding in the 1990s.
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14. 14

15. 15

16.  Aid from rich countries often can help alleviate famines in
the short term.
 Drawbacks to foreign assistance:
 Population must crowd together in “food camps” to receive
supplies.
 Lack of sanitation
 Quick spread of diseases
 Foreign aid tends to be short-lived as people’s attention moves
elsewhere.
 Ex: Indonesian tsunami of 2004, Hurricane Katrina of 2005, Haiti
earthquake of 2009, Pakistan floods of 2010
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17.  An estimated 90% of the world’s food calories
come from 14 species of plants.
 Three of those crops deliver a majority of world’s
nutrients: wheat, corn, and rice.
 Main nutrient component of these foods is
carbohydrates.
 The major food staples are all plants.
 Cheaper and easier to produce.
 Why? Remember the energy pyramid?
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19. 19

20.  Meat and dairy products are all high in protein, iron, and
come from animals.
 As incomes rise in developing countries, food choices shift
towards higher-quality and more expensive foods.
 60% of production occurs in lesser developed countries.
 Meat requires a high amount of grain to produce.
 15 pounds of grain to produce 1 pound of meat.
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21.  Seafood is the biggest
protein source in many
island and coastal
countries.
 Annual catches of ocean
fish rose by 4% annually
between 1950-1988.
 Many areas of ocean are
now so overharvested
that large-scale fishing
is unsustainable.
 Nearly half of seafood
harvested is now farmed. 21

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23. 23

24. 24

25.  Much of the food produced in the developed world is the
result of industrialized agriculture.
 Dependent on the use of heavy
equipment, fuel, fertilizers, pesticides, and irrigation.
 Most food is grown as a monoculture, or single-crop
farming.
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26.  Total food production has increased steadily in the last
50 years, in spite of a decrease in the actual number of
farms.
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27.  The green revolution marked three major changes in farming
and food production:
1. Usage of monocultures of highly-bred or genetically
modified species.
2. Increased input of irrigation, fertilizer, herbicides, and
pesticides.
3. Produce more than one type of crop each year on a plot of
land.
 The net effect of the Green revolution and the industrial food
system has been to keep food prices artificially low.
 Americans only spend 10% of their household income on food.
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28.  Agriculture accounts for largest single share of global
water use.
 Most irrigation systems are inefficient.
 Only about 20% of water withdrawn for irrigation reaches
the plant roots.
 Where does the rest go?
 Two main types of irrigation systems:
 Overhead sprinkler systems
 Underground drip systems
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30. 30

31.  Lack of three nutrients can slow plant growth:
nitrogen, phosphorous, and potassium.
 Adding these nutrients via fertilizer usually stimulates growth
and increases crop yields.
 1950 - Average of 7kg/acre used
 2000 - Average of 25kg/acre used
 Adding fertilizer and manure is replenishes soil nutrients
depleted from previous years.
 Problems with fertilizer?
 Can runoff into water sources and cause aquatic plants
(algae) populations to expand rapidly
 Manure can cause bacterial contamination
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32.  Industrialized farming is energy-intensive.
 Energy use in agriculture has risen for two reasons:
 Increase in use of machines
 Spraying of chemical pesticide and fertilizers
 In the U.S., the food system consumes 16% of total energy
use.
 Most foods require more energy to produce, process, and
transport than we yield from them.
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33.  Biological pests are any organisms that reduce crop
yields.
 Examples: Insects, birds, rodents
 Pesticides are chemicals that are used to kill or repel
biological pests.
 Half of current crop yields might be lost in the absence of
pesticides.
 Residue from synthetic pesticides often remains on the
skin of some fruit.
 Organic foods, by definition, do not use synthetic
pesticides and herbicides.
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34.  The single biggest individual benefit of buying organic is the avoidance of
pesticide residues. Not all produce has the same amount of residue.
 The “Dirty Dozen” – most contaminated produce
 Celery (64 different pesticides have been detected)
 Peaches
 Strawberries
 Applies
 Blueberries
 Nectarines
 Bell peppers
 Spinach
 Kale
 Cherries
 Potatoes
 Grapes (up to 34 different pesticides detected)
Source: www.thedailygreen.com (list updated yearly)
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35.  The “Clean Fifteen” – least contaminated produce
 Onions
 Avacados
 Sweet Corn
 Pineapple
 Mango
 Asparagus
 Sweet peas
 Kiwi
 Cabbage
 Eggplant
 Papaya
 Watermelon
 Broccoli
 Tomato (look for greenhouse grown)
 Sweet potatoes
Source: www.thedailygreen.com (list updated yearly) 35

36. 36

37.  The industrialization of agriculture applies to the raising
of livestock, both for meat and dairy.
 The traditional method of raising animals in open pasture
is now largely a relic of the past, replaced by highly-
mechanized large-scale operations.
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38.  Dairy cows are special breeds chosen for high milk
production.
 About half of the U.S. dairy cows are raised in confined
indoor pens.
 As with other mammals, cows only produce milk for
about 10 months after giving birth.
 Must be continuously impregnated to continue milk
production.
 Female calves are kept within the herd
 Male calves are usually sent to veal crates.
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39.  The advantage of raising dairy cattle indoors is that all
aspects of their growth, feeding, and behavior can be
monitored and controlled.
 Cows leave their pens twice a day to be milked
mechanically.
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40.  The disadvantage is the rapid spread of disease due to
the crowding and high amounts of waste manure.
 To prevent this, antibiotics are commonly administered
to the cattle.
 Nearly half of all antibiotics used in the U.S. are used in
farm animals.
 Farms may also inject their cattle with Bovine Growth
Hormone (BGH) to increase milk production.
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41.  There are significant consequences to the use of additive
hormones and antibiotics in cattle feed.
 Overuse of antibiotics is increases the risk of bacteria
evolving resistance to the antibiotic. When this
occurs, the antibiotic becomes unusable.
 The use of BGH has multiple effects:
 The overall health of the cows is affected:
 Increased likeliness of mastitis (infection of the udders)
 Increased rate of lameness
 Reduced fertility
 There are also effects on the milk itself:
 Increased growth hormone in the milk
 Increased pus in the milk, causing it to go sour more quickly 41

42.  Penicillin is ineffective 25% of the time for strep throat;
amoxicillin is ineffective 18% of the time.
 Source: University of Rochester Study
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44.  Calves are kept in small crates that minimize the amount
of movement they are able to make.
 Their diet is intentionally iron-deficient. This keeps
their flesh pale
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45. 45

46.  The majority of hens (~95%) that supply eggs are raised in
battery cages.
 These are small cages with slanted floors to drain waste.
 Hens are confined within small cages their entire life.
 USDA recommendations for cage size:
 Cages are usually 16 inches wide and contain 4 hens.
 The highly restricted movement of the hens leads to unusually
aggressive behaviors.
 Beaks are cut or seared off to prevent fighting.
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47.  Chicks that are hatched are sorted by gender; females are
kept; the males are killed and discarded.
 The layer hens are subject to near constant light to
encourage greater egg production.
 Fatigue and mineral depletion are common .
 Egg production begins to decline when the hens reach
about 12 months.
 At this point they are slaughtered and used in processed
foods (soup, flavoring, pet foods, etc)
 The use of antibiotics and growth hormones is illegal in
all poultry.
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48.  Broiler hens are chickens bred and raised specifically for
meat.
 They have much larger thighs and breasts than normal;
making them very heavy and often unable to stand or walk
normally.
 Broiler chickens are raised in pens instead of cages to
prevent bruising.
 Beaks and toes are removed to prevent fighting.
 The chickens reach their slaughter weight in about 2
months.
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51.  Pigs are very sensitive animals, prone to sunburn and
heat stress.
 As a result, they are primarily raised indoors in
temperature-controlled “hatch pens”.
 Tails are usually cut off at birth to prevent biting – a
common issue in overcrowded pens.
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53. 53

54.  Cattle / Pigs
 The animals are knocked unconscious either by electric shock or
with a bolt gun.
 They are hung upside down by their hind legs.
 The carotid artery and jugular veins are cut, killing the animal by
bloodloss.
 Poultry
 The animals are hung by their feet on a conveyor belt.
 They are passed through electrified salt water to stun them
unconscious, then their throats are cut.
 The carcasses are then moved into a vat of boiling water, which
makes feather removal easier.
 Kosher/Halal
 Animals are not stunned before slaughter.
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56. 56

57. The “Smoking Fry” experiment
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58.  Beef
 The leftover fat, connective tissue, and organ pieces from
slaughter is liquefied, mixed with ammonia (to reduce
bacteria), and combined with ground beef.
 Carbon monoxide may also be added to meat packaging to
preserve the red color as long as possible.
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60.  The factory farming process makes food much cheaper than
conventional methods.
 One big downside is an increase in the number of food
recalls.
 2010 Recalls
 228 million eggs ( Salmonella )
 2009 Recalls
 Nestle Toll House cookie dough ( E.coli )
 Pistachios ( Salmonella )
 Products containing peanut butter / paste ( Salmonella )
 2008 Recalls
 Beef recall ( cattle were not inspected properly )
 Maple Leaf brand deli meats ( listeriosis )
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61. Produced by Free Range Studios
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2003,2006

62.  Cage Free  Organic
 Chickens are not kept within  No unnatural feeds or feed
cages, but may still be high- additives given to animals.
density indoor pens.  No additives in the final
product.
 Certified Humane  Does not address treatment
 Chickens are uncaged and of animals
“must be able to perform
natural behaviors such as
nesting”.
 Free Range
 Animals are kept outdoors
and allowed to roam.
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63.  Arable Land – Land that is fertile and can be used to grow
crops.
 Soil - A complex mixture of minerals, decomposing organic
materials, and living organisms.
 Soil is generated from rock by two processes:
 Physical weathering – Rock is broken down by wind and
water
 Chemical weathering – Rock reacts with substances such as
acid or water.
 The best soils for farming have deep topsoil layers.
 Grasslands, deciduous forests.
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64. 64

65.  Much of the arable land on Earth has been lost.
 Estimates:
 3 million hectares of cropland ruined annually via erosion,
 4 million transformed into deserts
 8 million paved or built upon.
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66. Serious concern
Some concern
Stable or
nonvegetative
Stepped Art
Fig. 10-9, p. 216

67.  Desertification – Dry areas become more desert-like due
to human activities.
 Overgrazing
 Global climate change
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68.  Erosion is any natural process that redistributes soil and
minerals across the earth.
 Erosion becomes a problem when it occurs too quickly.
 Two biggest causes of erosion:
 Wind
 Water
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69.  Sheet Erosion - Thin, uniform layer of soil removed by
high winds.
 Rill Erosion - Small rivulets of running water gather and
cut small channels in the soil.
 Gully Erosion - Rills enlarge to form channels too large to
be removed by normal tillage.
 Streambank Erosion - Washing away of soil from
established streambanks.
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72. 72

74.  Wind can be a strong force of erosion, especially in a dry
climate and on flat land.
 Wind erosion is worsened by intensive farming practices:
 Planting crops in rows, leaving the soil in between exposed.
 Having fields completely free of weeds
 Removal of windbreaks such as trees
 No crop-rotation or resting periods
 Continued monocultures
 Growing the same crop every year
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77.  Managing Topography
 Contour Plowing - Plowing across slope to slow flow of water.
 Strip Farming - Planting different crops in alternating strips
along land contours.
 Terracing - Shaping land to create level shelves of earth to hold
water and soil.
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78. Fig. 10-19, p. 229

79. Fig. 10-19, p. 229

80. Fig. 10-19, p. 229

81. Fig. 10-19, p. 229

82.  Providing Ground Cover
 The most erosion occurs in fields that are bare – do not
have any cover.
 Ways to avoid bare ground:
 Leave crop residue after harvest.
 Plant different crops each season.
 Lay down mulch.
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84.  Genetically Modified Organisms (GMO’s)
 Contain DNA possessing genes borrowed from unrelated
species.
 Can produce crops with new traits only found in other species.
 Opponents fear GMOs are untested and may cause health
effects when eaten, such as allergies
 60% of all processed foods in North America contain
transgenic products.
 Corn and soy
84

85. Food Properties Percent Modified in US
Resistant to certain
Soybeans 89%
herbicides
Resistant to certain
herbicides
Insect resistance - using Bt
proteins from a bacterium
Vitamin-enriched corn,
Corn 60%
with 169x increase in
Vitamin A,
6x the vitamin C and 2x
folate.
Cotton (cottonseed oil) Pest-resistant cotton 83%
Variety is resistant to the
Hawaiian papaya 50%
papaya ringspot virus. 85

86. Food Properties Percent Modified in US
Ripening enzyme is
Taken off the market due to
Tomatoes suppressed, lengthening shelf-
commercial failure.
life.
Industrial production
Produces amylopectin instead of amylopectin for glossy
Potatoes
of starch. paper coatings and
adhesive cement.
Canola Resistance to herbicides, 75%
Resistance to certain
Sugar cane pesticides, high sucrose ?
content.
Sugar beet Resistance to herbicides ?
Produces its own bioinsecticide
Sweet corn ?
(Bt toxin)
Genetically modified to contain
Rice ? 86
high amounts of Vitamin A