Food Resources
Chapter 13
We’re not in Kansas anymore
New technology for Kansas Prairies
Polyculture
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Plant perennial grasses
Legumes (return nitrogen to the soil)
Sunflowers
Grain crops
Plants that provide natural pesticide
This makes Toto very happy
Perennial polyculture blended with
monoculture helps in the following way
Less plowing – lower soil erosion
Less pollution from pesticide use/fertilizer
Less need for irrigation (deep root systems)
How is the world fed?
 Cropland (produce grain mostly)
 Rangeland (livestock)
 Oceanic fisheries
 Food production has increased to keep up with
the growing population
 Machines,inorganic fertilizers,irrigation,
pesticides, high-yield varieties of wheat/rice,
increased density in feedlots, aquaculture
What are the implications of
increased food production
Environmental degradation
– Soil loss, lost habitat, contaminated water
Pollution – nitrogen, phosphates, pesticides
Lack of water – diminishing water table
Overgrazing – reducing grassland
productivity
Overfishing – reducing fish stocks (?)
Loss of ecological services
What do we really eat
 (other than McDonalds, of course)
 15 plants and 8 animals make up 90% of the food
we consume
 Big 3 grains – wheat, rice, corn
 Big 3 meats – beef, pork, chicken
 Fish – important food source for more than a
billion people
 What, no tofurkey?
Types of Agriculture
Industrialized or high input
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Uses high amounts of:
fossil fuel energy
Water
Commercial inorganic fertilizer
Pesticide use
monocultures
Types of Ag continued
Plantation Agriculture (a variety of
industrial)
– In tropical areas
– Growing cash crops (tobacco, coffee,
sugarcane, cocoa, bananas, soybeans)
Types of Ag continued
Traditional Subsistence Ag
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Uses mostly human and animal labor
Low use of inorganic fertilizer
Low pesticide use
Usually food for family only, small surplus
Includes shifting cultivation in tropical areas
and nomadic livestock
Types of Ag continued
Traditional Intensive Ag
– High labor
– High fertilizer/pesticide use
– High yield (able to sell for profit)
– Typical of rice production
Green Revolution
 High input monocultures to the rescue?
 Three steps
– Developing high yield monocultures
– Using large inputs of fertilizer/pesticide/water
– Increase the frequency and density of farming
First green revolution –US and Europe
Second green revolution – Tropical areas especially rice
in Asia
The US and Food
 With only 0.3% of the farm labor force, the US
produces 17% of the worlds grain
 US spends only about 10-12% of their income on
food (18% Japan, 40-70% developing countries)
 In the US it takes 10 units of fossil fuel to
produce 1 unit of food ( as compared to intensive
which takes 1 unit to produce 10)
Growing Techniques
 Monoculture – only one plant type
 Interplanting – several monocultures on one plot
of land (including)
– Polyvarietal cultivation – several varieties of the same
plant
– Intercropping – two or more plant types grown at the
same time
– Alley cropping – plants and trees together
– Polyculture – several types of plants on one plot at one
time harvested at different times usually
Increase in food production
Since 1950 grain production has tripled
Average food price dropped 25%
Food traded worldwide quadrupled
Meat production has risen for 41 years
Problems with production
Areas with 2 billion (sub-Saharan Africa)
growth is surpassing food production
Grain production has leveled off
– Limits to irrigation, fertilizer, pesticide
– Loss of topsoil, agricultural land, and
salinization of the soil
Nutrition
 Nutrition affects life expectancy, disease
resilience, and life quality
 Undernutrition – do not get enough food
 Malnutrition – do not get enough key nutrients
(vitamins and minerals)
 WHO says that 10 million die annually (most
under 5) from poor nutrition and diseases
associated with it
Effects of Food Production
Biodiversity loss – clearing land, pesticide
runoff, lack of predators
Soil degradation- erosion, loss of fertility,
salinization, desertification
Air pollution- fossil fuel emissions, dust
Water- sediment, fertilizers, pesticides,
aquifer depletion, increased runoff
Human Health- nitrates in water,
pesticides, bacterial contamination of meat
GMO
Genetically Modified Organisms
Faster than crossbreeding, less costly,
unlimited combination
Nearly 2/3 of US food in supermarkets
contains GMO’s
Do not know all the long term effects on
the environment
Meat Production
Rangeland – 40% of the planet’s ice free
land, mostly grasslands
Pasture – managed grasslands and
meadows, often irrigated, normally fenced
Rangeland plants- anchor soil, extract deep
water (survive drought), store nutrients
Most grasses can have the top eaten and
grow back easily
Problems with meat production
Concentrated production facilities
– Foul odor, water pollution (wastes) (+ aquifer)
Overgrazing
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Lower productivity of grasses
Reduces plant cover (soil erosion wind/water)
Compacts soil
Increase amount of woody shrubs
Major cause of desertification
Pesticide and pest control
Do you know
What are the problems with pesticide?
What are the different types of
pesticide?
When should pesticides be used?
How are pesticides part of a negative
feedback loop?
Pesticide problems
Kills many other organisms
Only about 2% reaches target species
Kills genetically weak species,
strengthening the species overall
Often the toxin has a long life span
Creates birth defects
Kills natural predators
Types of pesticide
Herbicides – weed killers
Fungicides – fungus killers
Nematocides – worm killers
Rodenticides – rat and mouse killers
DDT – first of the second generation
pesticides and world’s most used
pesticide in 1948. In the US most
pesticide is used on corn and cotton
(90% of insecticide and 80% herbicide)
Pros for pesticide
Human lives are saved by killing disease
carrying pests (mosquitoes)
Increased food supply
Increased profit for farmers
Pesticides work quickly to remove pests
When used appropriately the health risk to
humans is low compared to the benefit
(ACSH)
Pesticide info
Insecticide
Chlorinated hydrocarbons – DDT, aldrin,
diedrin, chlordane, toxaphene, mirex
These are the bad ones
Long lasting
Biologically magnified
Pesticide info continued
Most other types of pesticide are relatively
safe – low persistence (up to a few weeks)
and are not biologically magnified
Organophosphates – malathion, DDVP
Carbamates – aldicarb
Botanicals – extracted from plants
Micro botanicals – fungi, bacteria, protozoa
Synthetics – “lasso,” “roundup”
Bad types continued
Fumigants are generally bad. Not only
do they last a long time, and
biomagnify, they often are spread vast
distances with the wind
Carbon tetrachloride
Ethylene dibromide
Methyl bromide
Positive feedback loop
Pesticides increase genetic resistance making bugs
stronger each generation
Natural predators are also killed
New pest populations can explode when predators
are killed
Leads to pesticide treadmill – having to use more
and more pesticide to kill the pests because of the
feedback loop
First pesticide awareness
Rachel Carson – Silent Spring, opened
the publics’ eyes to the danger of
pesticide.
Linked birth defect rise in population
back to pesticide use.
The real problems
Pesticides linger in the air and on foods
Workers are exposed to high levels
Animals are exposed to toxins while pregnant
Tolerance levels are not set based upon
health concerns, but upon crop concerns
There is little enforcement of use of
pesticides