Transcript Chapter 11 PowerPoint

Chapter 11: Feeding the World
Nutrition
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Food Security
Macro vs. micro nutrients
Malnutrition
Undernutrition
Overnutrition
– WHO | Obesity and overweight
• Malnutrition and Gender Inequality
Protein Energy Malnutrition
• Marasmus
• Kwashiorkor
Ways to reduce childhood deaths
from hunger and malnutrition
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Immunize
Breastfeed
Prevent dehydration
Provide family planning
Increase education for women
Provide Vitamin A
Famine
• Sudan, Africa: Civil war since 1983
• Mother describes life in Southern Sudan
• Teaching Farming Techniques
Animation: Land Use
PLAY
ANIMATION
Green Revolution
• Increased yields per unit area since 1940’s
Three steps:
– Developing and planting monocultures,
selective breeding or genetically engineered
crops
– Increased use of fertilizers, pesticides and
water
– Increasing the intensity and frequency of
cropping
– The Green Revolution: Waging A War Against
Hunger
Agriculture
• Where would you find the following types
of agriculture and what types of crops are
grown by each?
– Traditional (low input)
– Industrial (high input)
– Plantation
Industrialized agriculture
Plantation agriculture
Intensive traditional ag.
Shifting cultivation
Nomadic herding
No agriculture
Fig. 13-4, p. 275
Traditional subsistence agriculture
Traditional intensive agriculture
Industrial agriculture (high input)
•What are the high inputs required to make
industrialized agriculture work?
•Tend to be monocultures
Plantation agriculture
• Type of industrialized agriculture
• Problems associated with plantation agriculture
Coffee plantation Kenya
Tea plantation in Malaysia
Organic Farming
• Food grown
without the use of
synthetic
pesticides and
fertilizers
• Disadvantages of
organic farming?
Three ways to decrease hunger, malnutrition
and the harmful environmental effects of
agriculture:
– Slow population growth.
– Sharply reduce poverty.
– Develop and phase in systems of more
sustainable, low input agriculture over the
next few decades.
Back to the Start
Figure 13-34
Grazing
Ungrazed
Grazed
Metabolic
reserve
Recovery
Metabolic
reserve
intact
Metabolic
reserve
Overgrazing
Ungrazed
Overgrazed
Metabolic
reserve
Death
Most of
metabolic
reserve
eaten
Death
Producing More Meat
• Rangelands vs. feedlots (Concentrated Animal
Feeding Operations - CAFO’s)
The Meatrix
Meatrix 2
Meatrix 2.5
Grocery Store Wars
Trade-Offs
Animal Feedlots
Advantages
Increased meat
production
Higher profits
Less land use
Reduced overgrazing
Reduced soil
erosion
Help protect
biodiversity
Disadvantages
Need large inputs
of grain, fish
Efficient or
meal, water, and inefficient?
fossil fuels
Concentrate
animal wastes
that can pollute
water
Antibiotics can
increase genetic
resistance to
microbes in
humans
Hogs &
Water
Quality
Image of
Hog Farms
Fig. 13-21, p. 289
Use of antibiotics and steroids
in meat production
Animal Antibiotic Overuse Hurting Humans? - CBS Evening News CBS News
Growth steroids (hormones): cattle and sheep
Milk Production hormones: dairy cattle (not beef cattle)
No growth hormones allowed for poultry (turkey, chicken
and ducks) or pigs
Fishing Methods
Fish
farming in
cage
Trawl
flap Trawl
lines
Trawl bag
Long line
fishing
Trawler
fishing
Spotter airplane
Sonar
Purse-seine fishing
Fish
school
Drift-net fishing
Floa Buo
y
t
Lines with
hooks
Deep sea
aquaculture
cage
Turtle excluder device
Fish caught
by gills
Trade-Offs
Aquaculture
Advantages
High efficiency
High yield in
small volume
of water
Can reduce
overharvesting
of conventional
fisheries
Low fuel use
High profits
Dan Barber Video
Profits not tied
to price of oil
Disadvantages
Needs large inputs
of land, feed, and
water
Large waste
output
Destroys
mangrove forests
and estuaries
Uses grain to feed
some species
Dense populations
vulnerable to
disease
Tanks too
contaminated to
use after about 5
years
Fig. 13-24, p. 292
Solutions
More Sustainable Aquaculture
• Use less fishmeal feed to reduce depletion of other fish
• Improve management of aquaculture wastes
• Reduce escape of aquaculture species into the wild
• Restrict location of fish farms to reduce loss of
mangrove forests and estuaries
• Farm some aquaculture species in deeply submerged
cages to protect them from wave action and predators
and allow dilution of wastes into the ocean
• Certify sustainable forms of aquaculture
Fig. 13-25, p. 293
Government Policies and Food
Production
• Governments use three main approaches
to influence food production:
– Control prices to keep prices artificially low.
– Provide subsidies to keep farmers in
business.
– Let the marketplace decide rather that
implementing price controls.
What is a subsidy?
• Financial assistance from the government to
assist a business
• Agricultural subsidies:
– Direct payments to farmers for certain levels of output
– Price supports that keep prices higher to increase
revenue for farmers: Ex: the government sets a
minimum price for sugar that it guarantees to sugar
growers. If the market price drops below that level,
the government makes up the difference.
– Protection against imports of certain products (sugar,
dairy) to keep market for local producers
Animation: Pesticide Examples
PLAY
ANIMATION
Persistence
Resistance
THE GENE REVOLUTION
• To increase crop yields, we can mix the
genes of similar types of organisms and
mix the genes of different organisms.
– Artificial selection has been used for centuries
to develop genetically improved varieties of
crops.
– Genetic engineering develops improved
strains at an exponential pace compared to
artificial selection.
• Controversy has arisen over the use of
genetically modified food (GMF).
Mixing Genes
• Genetic
engineering
involves splicing a
gene from one
species and
transplanting the
DNA into another
species.
PBS - harvest of fear: what
about this fish?
Proposition 37 in CA
Figure 13-19
How Would You Vote?
• Do the advantages of genetically
engineered foods outweigh their
disadvantages?
– a. No. The impact of these foods could cause
serious harm to the environment or human
health.
– b. Yes. These foods are needed to combat
world hunger.
Solutions: Making the Transition to
More Sustainable Agriculture
• More research,
demonstration
projects,
government
subsidies, and
training can
promote more
sustainable
organic
agriculture.
Figure 13-35