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The Green R evolution and Industrial Agriculture. Chapter 11. Industrial Agriculture. Synonymous term: Agribusiness Synonymous term: Conventional Agriculture Mechanization & Standardization Dependent on Energy Inputs from Fossil Fuels. The Energy Subsidy in Agriculture. Energy inputs
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Industrial Agriculture • Synonymous term: Agribusiness • Synonymous term: Conventional Agriculture • Mechanization & Standardization • Dependent on Energy Inputs from Fossil Fuels
The Energy Subsidy in Agriculture • Energy inputs • Fossil fuels -v- Human energy • Developing nations -v- developed nations • The energy subsidy (input:output) • When you go to the grocery store, it is 10:1 • Food choices are really energy input choices
The Energy Subsidy in Agriculture • Fossil Fuels Inputs to: • Synthesize Fertilizer • Synthesize pesticides • Operate machinery • Pump irrigation water • Harvest food • Prepare food for transport • Food transport The average food item travels 2,000 km from the farm to the plate
Green Revolution • small family farms • a lot of human labor • low fossil fuel inputs • To large industrial operations • To fewer people needed • To Machinery
Green Revolution Practices • Mechanization • Irrigation • Fertilization • Monocropping • Pesticides
(1) Mechanization • Farms require work • Replace humans/animals with machinery • Fossil fuel prices low • Cost of labor is high • Creates an “Economy of Scale” • Cost of production falls as output increases • Profits increase with increasing size of farms
(1) Mechanization • Agribusiness’ can outcompete small-scale, family farmers • Depletes a nonrenewable resource • Air pollution
How big is a typical farm? • It is know that 1mi2 is 640 acreas and that there are 0.4 hectares in an acre. How many hectars (ha) is the typical agribusiness farm field that is 2mi2? • Tangent: Helicopter Cowboys!
(2) Irrigation • Increase crop growth rates • Grow crops where they could not grow before • 16% world land is irrigated & produces 40% of the world’s food
(2) Irrigation-problems • Groundwater depletion/overdraw • Saltwater intrusion • Waterlogging • Salinization
(3) Fertilizers • Replenish lost nutrients from crop removal • N-P-K • Organic –v- synthetic • Manipulate the formulation to suit the crop or soil • Easily absorbed • 1960: 20 million tonnes2007: 160 million tonnes
(3) Fertilizers-problems • Manufacturing fertilizers requires fossil fuels • Runoff leads to algal blooms and dead zones • No addition of organic material
(4) Monocropping • Large plantings of a single variety(wheat & cotton)> 405ha • Increased efficiency • All planted at the same time • High yield/disease resistant strains • Harvested at the same time • Uniform fertilizer or pesticide application • Increased yields
(4) Monocropping-problems • Soil erosion • Exposed soil of 1mi2 before planting • Typical US farm loses 1 metric ton/ha topsoil
(4) Monocropping-problems • vulnerable to pests • Genetic homogeneity is unstable • Genetic variation increases stability of a system
(4) Monocropping-problems Wasps are parasites
(4) Monocropping-problems • vulnerable to pests • Genetic homogeneity is a feeding frenzy • Removes habitat for beneficial predators • Ladybugs & parasitic wasps
(4) Monocropping-envi. problems • vulnerable to pests • Removes habitat for beneficial predators • Ladybugs & parasitic wasps
(5) Pesticides • Natural/synthetic • USA > 227 million kg applied (1/3rd of world’s pesticides) • Prevents crop damage so increases yields! • Easily applied • Rapid response to infestations • Great Control with a single application • Broad spectrum –v- Selective
(5) Pesticides-Environmental Problems • Kills other than the target species
(5) Pesticides-Environmental Problems • Kills other than the target species • Persistence (DDT) • Bioaccumulates in organisms fatty tissues • Biomagnifies as it moves up trophic levels
(5) Pesticides-Environmental Problems • Kills other than the target species • Persistence (DDT) • Pest Resistance • Pesticide treadmill