2. Main Topics
Methods of producing food
Increasing food production
Environmental effects of food production
Issues of sustainability
3. Sources of food worldwide
Of 30,000 edible plants, only 15 spp.
supply 90% of our food
Primary plants:
wheat, corn, and rice
Provide < ½ calories people consume
Primary animals:
cattle, pigs, and chicken
2ndary: Eggs, milk & cheese
4. Major Types of Agriculture
Traditional subsistence
Shifting cultivation
Nomadic herding
Traditional intensive
Plantation
Industrialized
5. Fig. 12.3a, p. 264
Industrialized
agriculture
in developed
countries
Intensive
traditional
agriculture
in developing
countries
Land
Labor
Capital
Fossil fuel
energy
Land
Labor
Capital
Fossil fuel energy
6. Fig. 12.3b, p. 264
Shifting cultivation
in tropical
forests
in developing
countries
Nomadic
herding in
developing
countries
Land
Labor
Capital
Land
Labor
Capital
8. Fig. 12.8a, p. 268
2,000
1,500
1,000
500
0
Grainproduction
(millionsoftons)
1950 1960 1970 1980 1990 2000 2010
Total World Grain Production
9. Fig. 12.8b, p. 268
400
350
300
250
150
Percapitagrainproduction
(kilogramsperperson)
1950 1960 1970 1980 1990 2000 2010
Per Capita World Grain Production
200
10. Green Revolutions
First green revolution
(developed countries)
Second green revolution
(developing countries)
Major International agricultural
research centers and seed banks Fig. 12.4, p. 265
11. Producing Food by Green-
Revolution Techniques
High-input monoculture
Selectively bred or genetically-engineered
crops
High inputs of fertilizer
Extensive use of pesticides
High inputs of water
Increased intensity and frequency of
cropping
12.
13. Results of Green Revolution: Mixed
• Higher yields per acre when inputs
available
• Lower yields when inputs unavailable
• Increased dependence on cash economy
• Increased dependence on fossil fuel
• Increased imports of inputs
• Income disparity??
• Migration to cities??
14. Unintended consequences: Killer Bees
Mild-mannered, low honey producing Italian bee
X
Aggressive, high honey producing African bee?
Hope for a mild-
mannered, high
producing bee
Instead, got an
aggressive, low
producing bee
Worse yet – it escaped, and is interbreeding with other
bees making them aggressive & low producing too!
15. Environmental Effects of Food
Production
Biodiversity loss
Soil degradation
Air pollution
Water pollution
Human health