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Feeding the World

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Ms. Farrell

on 10 May 2017

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Transcript of Feeding the World

Feeding the World
Are we succeeding in feeding?
In this unit, we will look at
1. Human nutrition requirements
2. The history of agriculture and the green revolution
3. Genetic Engineering
4. Alternatives to industrialized agriculture
5. Modern Agribusinesses

Nutrition Definitions
Undernutrition: Not consuming enough calories to be healthy
The average person needs 2,200 calories daily
Not consuming enough calories causes individuals to be susceptible to disease
In children, undernutrition can lead to brain damage and a lower IQ
should not be confused with

Malnutrition: Regardless of the number of calories, the individual is not receiving the correct balance of proteins, carbs, vitamins and minerals
Estimates from the World Health Organization: 1/2 the world is malnourished.
Food Security Vs Food Insecurity
Food Security
A condition where people have access to healthy, safe, and nutritious food to meat their dietary needs

Must have the social, economic, and physical ability to meet these needs
Food Insecurity
Condition where people do not have adequate access to food
Famine: A large number of deaths due to starvation in a relatively short period of time
5 deaths/10,000 people/per day
Famine can be caused by:
crop failure
political issues
Overnutrition: the ingestion of too many calories, causing a person to be overweight
overnutrion has increased even while undernutrition increases
overnutrition can cause heart disease, diabetes, and stroke
Overnutrition can co-occur with malnutrition
foods being consumed do not contain the necessary nutrients needed
occurs often in developing countries
Grains: Make up the largest component of the human diet
Most common:
Meat: Second largest component of the human diet
A person's income is correlated with how much meat they eat

What makes up the human diet?
Why is there malnutrition?
There is enough
alone to feed 8 billion people
Grain makes up only
the amount of food produced globally
The food exists, but the distribution is uneven

And people cannot afford to buy it
A brief history of agriculture
10,000 years ago, agriculture began
Caused an increase in human numbers
20th century, farming became "industrialized"
Industrial agriculture
Energy Subsidy in Agriculture
Energy Subsidy
: The energy input vs energy output of food
Traditional, small scale agriculture has a relatively small energy subsidy
Average american diet: 10 calories input for every 1 calorie eaten
The Green Revolution (1940-1960):
A series of research developments that increased agriculture productions worldwide
Norman Borlaug: The father of the Green Revolution
Credited for saving over a billion people from starvation
Bred high-yielding crops
Expanded irrigation uses
Distributed fertilizer and pesticides to farmers
Fitz Haber: detonator of the population expansion
He learned how to pull nitrogen gas from the atmosphere and turn into a useable liquid for plants
population grew from 1.6 billion to the 7 billion today

Also, a twisted, twisted man....
Industrialized Agriculture
Think of all the labor that needs to be done for a farm:
Fields must be:
protected from pests
and prepared for the next season
Crops must be:
prepared for market
This mechanization has "weeded-out" small scale farms
Most of the energy subsidy comes from fossil fuels:
produce fertilizer and pesticides
operate tractors/equipment
pump water for irrigation
harvests and transport
Say we have two farmers

Both start as family operated, small scale farmers
But then...
Farmer "A" inherits a decent sum of money

He buys 300,000 dollar tractor which allows him to distribute fertilizer to his crops more easily

as a result, he significantly increases his yearly crop yield

Farmer B cannot afford to buy a tractor
His crop yield remains the same
Supply and Price
What happens to the price of an item as the supply of the item increases?
So because farmer A
increased the supply
Price of the crop decreases
So even though farmer B is
producing the same amount of product
he had the prior year
He is making less
While Farmer A is profiting more
Farmer B goes out of business
farmer A buys his land
And doubles the crop production of farmer Bs
And causes farmer "C" to go out of business
Farmer A buys his land.....
Crop prices decrease more
Irrigation has many benefits to agriculture:
transformed 1 million acres of desert in California into farmland
16% of irrigated land produces 40% of food supply
The Good
The Not so Good
Klamath River Case Study
: salts from irrigated water builds up in soils
can reach toxic levels in soils and impede plant growth
: soil remains waterlogged for extended periods of time
plant roots cannot get oxygen, plants die
Growing and harvesting crops depletes nutrients in soils
Nutrients need to be replenished
This is done through the use of fertilizer

organic fertilizer
animal waste (Poop!) that has been decomposed
Nitrogen is pulled from the atmosphere
Use of synthetic fertilizers has increased drastically
20 million tons used in 1960 to 160 million tons in 2007
The good
Easily applied to plants
amounts can be adjusted to suit the plant's needs
easily absorbed by plants
Without them, we'd probably starve....
The Not so Good
Requires use of fossil fuels
Energy intensive process making it
Run-off of excess nitrogen causes eutrophication
Does not add organic matter to the soil
reduces water retention capacity
large planting of a single species or variety of crop
Which image is representative of monocropping?
The Good
Easy and Efficient
All land is managed the same way
planting and harvesting occurs all at the same time
If pesticide or fertilizer is needed, the same type and amount can be used on all plants
Same pests, same nutrition needs
The Bad
Soil erosion
All crops are harvested at once
soil is exposed to wind and water
US looses 2.5 metric tons of soil to wind erosion per year
Pest attacks
monocropping provides a vast food supply
pests will reproduce rapidly
natural predators may not keep up with the exponential growth
AND, the natural predators habitat may have been destroyed from the monocropping

natural or synthetic substances that kill or control organisms that people consider pests
The US uses 227 million lbs a year
it accounts for 1/3 of the worlds pesticide use
Types of pesticides: pesticides can be defined based on what organisms they target and on the spectrum of the target
Target insects/invertebrates
Target plant species that compete with the crop
Broad-spectrum pesticides
Target a wide range of pests
These can kill beneficial species as well as the pests
The Target
The Spectrum
Selective (or narrow range) pesticides
Targets a narrow range of organisms

The Good
Rapid, easy response to pests
Increases food supply
Can benefit human health
kills pests that carry disease
The Not so Good
Pesticides can kill beneficial organisms
Ex: Pollinators
They can be
Means they remain in the ecosystem for long periods of time
This leads to
Some are
But it must be applied more frequently
Pests can become
which leads to a positive feedback loop:
The most commonly used pesticide
herbicide used to kill "broad-leaf" weeds
Used mostly on corn fields
the US sprays roughly 70% of corn fields with atrazine
Case Studies
discovered in 1939
effectively killed insects
was used as an insecticide in the US
was the most commonly used pesticide in the mid 1990s
Rachel Carson writes
Silent Spring
after observing fish and predatory bird die-offs
DDTs effects on humans
human carcinogen
damages the liver
damages reproductive system
DDT nearly drove bald eagle to extinction
The Infamous GMO
What is a GMO?
Genetically Modified Organism
Scientists isolate a gene from one organism and transfer the gene to another ogranism

The Good
Increased crop yield
strains of crop can be resistant to pests and harsh environmental conditions
reduces the need to use pesticides
Can fight malnutrition
Vitamin A rice (yellow rice)
Reduce blindness
insulin produced by bacteria
Potential Concerns
Human health?
there is little scientific evidence that shows GMOs are harmful to human health
GMOs breeding with wild natives
introduce GMO genes into natural environment
GMO regulations
No labeling system
Too difficult a task?
GM animals soon to hit the market, potentially
salmon that will reach maturity in 1/2 growing time
Alternatives to Industrialized Agriculture
Because it's so widely used, industrial=conventional
However, when reducing
isn't the top priority, other methods of farming can be used

Shifting Agriculture
Occurs in
moderately warm
climate with
Sometimes involves
trees and vegetation are cut down and burned
releases K, Ca, & Mg into soil
the nutrients are depleted quickly
This practice may cause
in arid areas
Land becomes a desert, unable to support plant life
occurs mostly in Africa
Clearing land and using it for only a few years until the soil is depleted of nutrient
Nomadic Grazing
A sustainable way to practice shifting agriculture
Animals are herded over long distances
Animals fertilize the grounds
Without lingering too long in one area, the plants regenerate
In general, Shifting Agriculture & Nomadic grazing works well in small populations
Sustainable Agriculture
seeks to fulfill the need for food while:
enhancing solid quality
minimizing the use of nonrenewable resources
providing economic viability for farmers

Use manure for fertilizer
one or more crop species are planted in the same field at the same time
Ex: Corn (requires lots of N) and Peas (produces N)
Crop Rotation:
every year plant the crops in a different location
Peas planted in one section leave nitrogen for the next year

May use
intercropping trees with plants
Trees block wind, preventing soil erosion
Provide fruit and firewood
Contour Plowing
Planting and Harvesting parallel to the contours of the land
prevents water erosion
Practices Tend to mimic traditional Farming Methods
No Till Agriculture
Tilling, or plowing, soil can have a negative impact on soil
can cause erosion due to the "loosening" of the soil
excess oxygen is introduced
organic matter is oxidized & reduced
causes increased CO2 emissions
No-Till Agriculture:
Farmers leave crop residue in the land between seasons
Roots remain in-tact, holding the soil in place
Decreases CO2 emissions
increases the need of herbicides so that weeds do not compete with the crops

Integrated Pest Management
A method of farming that aims to:
protect the environment
produce high quality crop
increase farmer profitability
Crop Rotation
some insects lay eggs in the soil
larvae cannot find crop when hatched
Distances crops from disease that may have formed in the previous growing season
Predator habitat
farmers will provide habitat for some predators of pests
Some do this through agrofarming
Farmers regularly inspect crops
pest infestations are caught early and contained
Pesticides are administered in smaller, more controlled doses
Saves the farmers money
Time & Training
Farmers must be trained in IPM management
And They spend more time in the fields
But farmers are more profitable
and the quality of the food increases
Organic Farming
Production of crops without the use of synthetic fertilizers or pesticides
Goals of organic farming:
Use ecological principles and work with natural systems rather than dominating them.
Keep as much organic matter and as many nutrients in the soil and on the farm as possible.
Avoid the use of synthetic fertilizers and pesticides.
Maintain the soil by increasing soil mass, biological activity, and beneficial chemical properties.
Reduce the adverse environmental effects of agriculture.
How do we know it's organic?
In 1990, US Organic Foods Protection Act
Established standards for defining organic food
Organic does not mean Family Owned
Organic farms used to be small
But have recently been increasing in size
Because soil health and pests must be monitored carefully, a larger labor force is generally needed
which increases the price of foods
How Do We Define Organic Food?
Meat and Fish Farming
Primary goal: Produce animals quickly and at a low price
Concentrated Animal Feeding Operations
In 2009, it was reported that 150 million animals were raised in CAFOs
Large, indoor structures designed for output
Animals are confined to small spaces
Increases efficiency of meat production
reduces energy demand from raising livestock
Fed antibiotics and food supplements
Problems associated with CAFOs
Can cause resistance to antibiotics in humans
Waste disposal
CAFOs produce 2,000 tons of manure annually
stored in waste lagoons
can contaminate drinking water
35,000 miles of river in 22 states
Groundwater contamination in 17 states

Meat alternatives
Free-range meats
limits use of antibiotics
Animals are able to graze
no additional feeding necessary
reduces energy subsidy
Manure and urine is spread on the field
natural way to provide fertilizer to animal feed
More land used
Higher cost
Fish and Shellfish
Third major source of food for humans
Tragedy of the Commons
Fish do not live their whole lives in one countries waters
Many live in international waters
No incentive for one country to limit it's fishing
Methods of Fishing
Fishing used to be limited by its difficulty
Now, its easy to catch large numbers of fish
Trawl Net
Long Line
Gill Net
Large nets are dragged behind boats
Midwater, bottom, and surface
Produces a lot of bycatch (nontarget species)
Bottom trawling can destroy ecosystems
remove coral, sea sponges, and plants
Long line of hooks is set in the water
A circular "wall" of fish is created using a net
Close the bottom to catch the fish
works well with schooling fish
Can prevent bycatch

A vertical wall that fish swim into
gills & heads get stuck
fish become entangled
Fisheries Management Plans
1992: Canadian government closes its Atlantic cod fisheries industry due to a massive fish collapse
Still closed to this day
Individual Transferable Quotas (ITQs)
management program in place in the US today
Fisheries management council establishes an allowance of fish fishermen can catch each year
If fishermen do not catch their quotas, they can sell them
Keeps effective fishermen in business
Protects the stocks

The Good
Less prone to runoff
Uses less energy (fossil fuels)
The Bad
Difficult to spread
Cannot manipulate the amount of nutrients
2006, Nature reports 30% of fisheries experienced a 90% decline in stocks
Called Fisheries Collapse
Sustainable Fisheries Act 1996
Shifted fisheries from economic minded to conservation minded
Full transcript