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APES Food Resources
“There are two spiritual dangers in not owning a farm. One is the danger of supposing that breakfast comes from a grocery, and the other is that heat comes from a furnace”.
Aldo Leopold
How is food produced?
Croplands
Croplands = 76%
Rangelands
Rangelands = 17%
Fisheries
Fisheries = 7%
Productivity Has increased over human history because…
• improved fishing gear and tech.• Use of inorganic chemical fertilizers• Irrigation• High-yield varieties of corn, wheat, and rice• Aquaculture • And….
Use of technology such as mechanized farm machinery.
Use of pesticides.
Use of feedlots (CAFOs)
Problems
a. environmental degradation
b. pollution
c. water shortages
d. overgrazing by livestock
e. Over fishing
f. loss of vital ecological services
Where will this waste end up when it rains?
What plants & animals feed the world?
15 plants
8 animals
+_______
= 90% of food eaten
grains such as corn, wheat, and rice are annuals and must be planted every year
these (3) supply about 50% of calories consumed worldwide
66% or world survives on these and not meat
Types of food production
Traditional
Traditional subsistence
- human labor and draft animals to produce enough to survive
- examples are shifting cultivation and nomadic herding
Traditional intensive- use of more labor and fertilizers to increase
production enough to sell excess
Types continued
Industrialized
- high input agriculture (25% of all agriculture)
- uses large amounts of fossil fuels, water, fertilizers, and pesticides to produce monocultures
Plantation agriculture
- a type of industrialized ag. Practiced in tropical regions for cash crops such as bananas, soybeans, coffee, cocoa
Green Revolution
To produce more food one can either farm more land, or get higher yields from the existing cropland. 1st Green Revolution from 1950s to 1970 involved:
1. developed high-yield varieties and planted monocultures
2. used large inputs of fertilizers, pesticides, and water
3. multiple cropping on same plot of land
2nd Green Revolution
From 1970s to present • additional dwarf
varieties developed for tropical climates
Major Environmental Concerns
Energy ConsumptionAgriculture in U.S. uses 18% of all commercial energy
used
Energy consumption
Meat production requires (3) units of fuel energy to produce (1) unit of food energy
Environmental ConcernsLoss of Biodiversity• from clearing land,
degradation, draining wetlands
• fish kills from pesticide use
• killing of livestock predators
• replacing wild species
with monocultures
Environmental Concerns
Soil Issues
• soil erosion
• salinization
• Waterlogging
• desertification
Air Pollution• greenhouse gas
emissions
• nitrogen oxides
• pesticide aerosols
Environmental IssuesWater Issues• aquifer depletion• surface and
groundwater contamination with pesticides and fertilizers
• sediment pollution from runoff
• fish kills
Environmental IssuesHuman Health• nitrates in drinking water• pesticides in drinking
water• livestock waster
contamination of drinking and swimming water
• bacterial contamination
of meat “blue baby syndrome”
Special Concerns with meat production
• 20% of US cropland produces grains just for livestock
• livestock uses 50% of water withdrawal from rivers and aquifers in USo irrigate cropso wash away manure
• manure contamination of local waterways
• topsoil erosion from livestock grazing
More problems with meat production• livestock responsible for 16% of methane emissions
(greenhouse gas) resulting from…….
•….no silly, belching
•More than 1/3 of all raw materials and fossil fuels consumed in U.S. are used in animal production
•Livestock produces 20x more waste than the country’s entire human population
Fisheries & Overfishing
• Fish are being caught at a rate that exceeds their ability to reproduce (replenish)
• Role of technology and fishing practices• By-catch• Common property resource and Tragedy of the
Commons
“There is no bad guy, all the incentives are there for overfishing to happen”
Sustainable fishing?
Techniques
Laws
Education
Consumer practices
Solutions1. clear more land?
2. increase yields?
3. irrigating more land?
4. urban / rooftop gardens?
5. establish closed fisheries?
6. establish quotas?
7. create areas where fish are not caught?
8. fish farms & aquaculture?
9. enforcement?
Government’s role in food production (policy)
Farming depends on:• weather• crop prices• pests• diseases• interest rates• global market
Role of Government
So, most governments provide various forms of assistance to farmers because of the need for a reliable food supply.
• This keeps food prices artificially low
• $100 billion per year in subsidies is given to US farmers to help keep them in business and to encourage them to increase food production
What do environmentalists say?
Environmentalists say• we should use subsidies to reward farmers and
ranchers who• protect the soil• conserve water• reforest degraded land• protect and restore wetlands• conserve wildlife• in general, practice more sustainable agriculture and
fishing
Would global warming have an impact on food production?
Changing rainfall patterns?
Sea level rise could flood lands?
Warmer climate could foster disease and pest growth?
Sustainability
Sustainable agriculture is characterized by• Limiting use of fossil fuels• Conserving topsoil• Limiting use of chemicals• Supports the use of organic fertilizers!• Treats long term quality of topsoil as a priority• Supports use of local inputs as much as possible
Food labeled “organic”
• Cannot be zapped with radiation• Cannot be genetically engineered• Cannot be fertilized with municipal sludge• No pesticides• No synthetic fertilizers
Organic Food