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Food ResourcesFood Resources
See Miller Chapter 12See Miller Chapter 12
Issues and Impacts of AgricultureENVS 1 Oct. 14, 2002
Main TopicsMain Topics
Methods of producing foodMethods of producing food
Increasing food productionIncreasing food production
Environmental effects of food productionEnvironmental effects of food production
Issues of sustainabilityIssues of sustainability
Sources of food worldwideSources of food worldwide
Of 30,000 edible plants, only 15 spp. supply 90% of our food
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 plants:wheat, corn, and rice
Provide < ½ calories people consume
Primary animals:cattle, pigs, and chicken 2ndary: Eggs, milk & cheese
Primary animals:cattle, pigs, and chicken 2ndary: Eggs, milk & cheese
Major Types of AgricultureMajor Types of Agriculture
Traditional subsistenceShifting cultivationNomadic herding
Traditional subsistenceShifting cultivationNomadic herding
Traditional intensiveTraditional intensive
PlantationPlantation
IndustrializedIndustrialized
Fig. 12.3a, p. 264
Industrialized agriculturein developed
countries
Intensive traditional agriculture
in developing countries
Land
Labor
Capital
Fossil fuelenergy
Land
Labor
Capital
Fossil fuel energy
Fig. 12.3b, p. 264
Shifting cultivation in tropical
forests in developing
countries
Nomadic herding indeveloping countries
Land
Labor
Capital
Land
Labor
Capital
Industrialized agricultureIndustrialized agriculture
Shifting cultivationShifting cultivation
Plantation agriculturePlantation agriculture
Nomadic herdingNomadic herding
Intensive traditional agricultureIntensive traditional agriculture
No agricultureNo agriculture
World Food ProductionWorld Food Production
Fig. 12.2, p. 263
Fig. 12.8a, p. 268
2,000
1,500
1,000
500
0
Gra
in p
rod
uct
ion
(mill
ion
s o
f to
ns)
1950 1960 1970 1980 1990 2000 2010
Total World Grain Production
Fig. 12.8b, p. 268
400
350
300
250
150
Per
cap
ita
gra
in p
rod
uct
ion
(kilo
gra
ms
per
per
son
)
1950 1960 1970 1980 1990 2000 2010
Per Capita World Grain Production
200
Green RevolutionsGreen Revolutions
First green revolution(developed countries)First green revolution(developed countries)
Second green revolution(developing countries)
Second green revolution(developing countries)
Major International agricultural research centers and seed banksMajor International agricultural research centers and seed banks Fig. 12.4, p. 265
Producing Food by Green-Revolution TechniquesProducing Food by Green-Revolution Techniques
High-input monocultureHigh-input monoculture
Selectively bred or genetically-engineered crops
Selectively bred or genetically-engineered crops
High inputs of fertilizerHigh inputs of fertilizer
Extensive use of pesticidesExtensive use of pesticides
High inputs of waterHigh inputs of water
Increased intensity and frequency of cropping
Increased intensity and frequency of cropping
Results of Green Revolution: MixedResults 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??
Unintended consequences: Killer BeesUnintended consequences: Killer Bees
Mild-mannered, low honey producing Italian beeX
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!