Sustainable Agriculture
IB Geography II
Objective
• By the end of this lesson, students will be able
to examine the principles of sustainable
agriculture and explain the environmental
costs of increasing food production.
• Essay Planning Tool Question: Examine the
principles of sustainable agriculture and
explain the environmental costs of increasing
food production.
Opening Reading Activity
• Close Read and Annotate: “The Worst Mistake in the History
of the Human Race” By Jared Diamond
• As you read, find:
– The main idea
– Supporting details that support it
• In elbow partners, discuss:
– The main idea and supporting details
– Your thoughts? Do you agree or disagree?
– Today we will be talking about sustainable agriculture.
How does this text apply to that?
Starting Activity
• Take the
next two
minutes to
read the
following
excerpt.
• Then
answer this
question: Is
sustainable
farming
possible?
Sustainability rests on the principle that we
must meet the needs of the present without
compromising the ability of future
generations to meet their own needs.
Therefore, stewardship of both natural and
human resources is of prime importance.
Stewardship of human resources includes
consideration of social responsibilities such as
working and living conditions of laborers, the
needs of rural communities, and consumer
health and safety both in the present and the
future. Stewardship of land and natural
resources involves maintaining or enhancing
this vital resource base for the long term.
Sustainability
• Sustainability is a
relatively
straightforward
concept to define but
is harder to achieve.
Think of it as a three
legged stool. The stool
needs all three legs to
remain standing
Sustainable Agriculture
• This term refers to the ability of a farm to
produce food indefinitely, without causing
irreversible damage to ecosystems.
• Sustainable farming reduces or prevents
environmental degradation (depletion of
vegetation loss of biodiversity, soil and water)
Key Principles of Sustainable
Agriculture
• Conservation and soil health
• Nutrient recycling e.g. animal waste being
used for fertilizer
• Biodiversity – this is helped through a minimal
use of chemicals on the land
• Animal welfare – more care taken with
animals, and different diets perhaps
• Fair wages and treatment for workforce – farm
is part of the rural community
Sustainable Yield
• Instead of pushing for the
maximum yield from the
land, these farms look to
produce the sustainable
yield (the food that can
be taken from the land
without reducing the
ability of the land to
produce the same in
future without external
support).
The Environmental Costs of Increasing
Food Production
• Increasing food production has brought a
greater reliance on mechanization and the use
of artificial inputs such as fertilizer, pesticides
and Energy Subsidies (sources of energy not
directly received from the sun; eg: fossil
fuels)
• Degradation: depletion of vegetation, loss of
biodiversity, soil and water.
Agribusiness
• Profit maximization requires economies of
scale: when more goods can be produced on
a larger scale with lower costs, economies of
scale is said to be achieved
• With agribusiness, farming operations have
been taken over by big businesses who are
generally more concerned with profits and
less concerned with the environment.
Increasing Livestock Yield
• Selective breeding
• The use of antibiotics
• Restriction of movement
The Meatrix
• http://www.themeatrix.com/
• As you watch, answer the following questions
in your notebook:
– What is the purpose of the video?
– What is the perspective of its creators?
– To what extent do you agree with the video’s
message?
Factory Farm
• Factory Farms house huge quantities of
livestock or poultry and emphasize high
volume and profit with minimal regard for
human health, safe food, the
environment, or humane treatment of
animals.
Feedlot
• Confined space used for controlled feeding of
animals.
History
Factory farming expanded in
1920’s, after the discovery of
vitamins A and D.
When these vitamins were
added to feed the animals they
no longer required exercise and
sunlight for growth.
This allowed animals to be
raised indoors, and started wide
spread of disease, which was
combated in the 1940’s with the
development of antibiotics.
• Farms have become
factories and the
animals raised in these
factories are mere
commodities.
• As of 2000, only 30% of
the 640,000 farms in
the U.S. provided
pasture for their
animals.
• All the rest are
confined in CAFOs
(Confined Animal
Feeding Operations).
Why They Exist
• Low cost — Intensive agriculture tends to
produce food that can be sold at lower
cost to consumers.
• Efficiency — Animals in confinement can
be supervised more closely than freeranging animals, and diseased animals can
be treated faster.
Potential Problems Caused By Factory
Farming
• Water Quality
• Air Quality
• Health Impacts
Water Quality
• Livestock collectively
generate 130 times more
waste in the U.S. than
humans.
• Large numbers of animals
on a small area of land
creates excess manure
• factory farms’ manure
“lagoons” often leak and
dirty both surface and
groundwater.
Impacts of Factory Farming
• May cause eutrophication (an ecosystem
response to the agricultural run-off carrying
fertilizers of nearby water)
Air Quality
• Manure lagoons release more
than 400 volatile chemicals,
including ammonia and
hydrogen sulfide, which can
cause seizures, brain
damage, or death.
• There is now extensive
literature documenting acute
and chronic respiratory
diseases among factory farm
workers.
Health Impacts
• Antibiotic Resistance: More than 70% of
antibiotics used in the U.S. are fed to
livestock. According to APHA, the emerging
scientific consensus is that antibiotics given
to livestock contribute to antibiotic
resistance in humans by creating bacteria
immune to some antibiotics or “superbugs.”
Eliminating Competitors
• Pesticides and Insecticides
• Can damage ecosystems
and the environment
• They are nonbiodegradable, and have
the tendency to
bioaccumulate in food
chains with serious
implications for humans.
• Bioaccumulation refers to
the accumulation of
substances, such as
pesticides, or other organic
chemicals in an organism
Maintaining Soil Health
• One of the simplest ways of maintaining soil
health is to rotate the crops (growing
alternative crops on land from year to year)
• The search for increasing profits can lead to
some farmers taking less care with the soil
– The Dust Bowl example
Reducing Biodiversity
• Intensive Commercial Farming: requires the
area under cultivation to be increased by
large-scale deforestation.
Deforestation
• The removal of trees may lead to:
– an increase albedo (the reflectivity of the ground
surface
– An increase diurnal (24 hour) temperature range
– Agrosystems (agricultural ecosystem) may lack
diversity
Food Miles
• The distance that food
travels from where it
is produced to where
it is consumed.
• A way of indicating the
environmental impact
of the food we eat
Energy Efficiency Ratios
• (EER) is a measure of the amount of energy
input into a system compared with the
output.
• Energy outputs/energy inputs
• Outputs should be more.
• An efficient farming system has an EER equal
to or greater than 1.
EER
• Inputs
–
–
–
–
–
–
–
–
Labor
Machinery
Vehicle fuel
Fertilizers
Seeds
Irrigation
Pesticides
Electricity
• Outputs
– Crop yields
Farm Welfare
• This is of increasing
importance to consumers.
– Sales of food considers
animal welfare
– Local sourcing
– organic free-range foods
– Fair trade
• But… there is often a high
price.
Organic Agriculture
• A farming system that promotes sustainable
and biodiverse ecosystems and relies on
natural ecological processes and cycles, as
opposed to synthetic inputs such as pesticides
and fertilizers
Map Analysis Activity
• Where are the farms located in the United
States?
• Where are the organic farms located?
• Describe the differences and similarities in
their location.
• Why do you think the differences exist?
Spatial Distribution of American Farms
Spatial Distribution of Organic Farms
• Look at the map of Median Income
• What pattern(s) do you see in the relationship
of the location of organic farms.
• Look at the obesity maps provided.
• What do you see when you compare the
Organic Farms, Median Income, and Obesity
maps with on another?
Obesity Trends Among Adults
Elbow Partner Analysis
• What is the pattern?
• Why does the pattern exist?
• Why is the pattern important?
Food Desert
• A food desert is a geographic area where
affordable and nutritious food is difficult to
obtain, particularly for those without access to
an automobile. Food deserts usually exist in
rural areas and low-income communities.
• If a person lives more than 1 mile away from
the nearest grocery store, they are considered
to live in a food desert.
Food Deserts Case Study
• Sources for Evaluation:
– “America’s Food Deserts”, The Guardian
– “The Grocery Gap: Who Has Access to Healthy Food and
Why it Matters”, PolicyLink Excerpt: Findings, Pages 15-22.
– “Stranded in the Food Desert: Reconnecting Communities
with Healthy Food Options” Mari Gallagher
– http://www.youtube.com/watch?v=8My-iWjTBQ8
Eliminating America’s Food Deserts
– http://www.youtube.com/watch?v=4Jly-ofG_zE Living in a
Desert