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Food Security
• daily access to enough nutritious food to live active and healthy lives
• vs. “food insecurity” - chronic hunger, malnutrition
• enough food is produced to meet the basic nutritional needs of everyone on earth
• 1 out of 6 in less developed countries has food insecurity
Why is food security difficult to attain?
• poverty
• war
• corruption
• prolonged drought or heat are reasons
• climate scientist Battisti and food scientist Naylor (2007) : 90%+ chance that by the end of this century, 1/2 of world’s population will have food shortages due to climate change
Chronic Hunger and Malnutrition worldwide• most of world’s poor live on grain - wheat, rice, or
corn; lack protein, vitamins, minerals
• weak, vulnerable to disease, hinders mental, physical development of children
• according to UN Food and Agriculture Organization, 870 million suffer from food insecurity (1 in 8); 852 million are in developing countries (worldhunger.org)
• 16,400 children under 5 die prematurely daily
Overnutrition• same problems as underfed and
underweight - disease, lower life span, lower productivity and life quality
• 1.2 billion
• treatment for obesity-related illnesses = $147billion in U.S.
Vitamin and Mineral Deficiencies
• iodine - affect thyroid (metabolism); stunted growth, brain damage; 26 million children each year; 600 million - goiter
• iron - anemia; death in childbirth; 1/5 in the world are anemic
• vitamin A - 500K under 6 blind and 1/2 death within 1 yr.
Food Production
• 40% of world land used for food
• croplands = 11% of land; 77% of food
• rangeland, pasture, feedlot = 29% of land; 16% of food
• fish farms = 7% of food
• increases in all of these due to technology, irrigation, fertilizers, pesticides
Traditional Agriculture• 1/5 of world’s food crops
• polyculture
• 2 types:
• traditional subsistence agriculture sun, human labor, animals to produce enough for a family’s survival with little to sell
• traditional intensive agriculture same, but higher yield and some left to sell
Slash and burn• polyculture
• clear small plots, grow variety of crops until soil depleted, shift to other plots and repeat
• 10 - 30 yrs for recovery
• less fertilizer, less water, manure for fertilizer
• higher yields than monoculture
• main cause for deforestation
Industrialized agriculture
• monoculture- corn, wheat, rice
• not sustainable (biodiversity, relies on fossil fuels, neglects nutrient cycling)
• 80 percent of world’s food
• heavy equipment, machine technology, major transportation systems, factory-style practices
• high water and irrigation, lg. quantities of synthetic fertilizer, pesticide, fossil fuel use
• plantation agriculture - tropical, less developed countries; bananas, soybeans
Industrialized Agriculture: Green Revolution
• develop and plant monocultures of genetically engineered high-yield varieties of key crops
• produce high yields using water, fertilizer, pesticide
• multiple cropping - increase the number of crops grown annually on a plot of land
• wastes harm the environment
• decrease in biodiversity
• human health issues
• development of synthetic fertilizers in 1930s, develop new crop varieties
• engineering farm equipment replaced draft animals
• rural labor decreased - only 2 percent of workforce
Benefits of Industrial Agriculture
• increased yields (30 bushels of corn per acre in 1920 to 134 per acre in 1999)
• reduced hunger
• affordable food
• increased export markets
• large, profitable agriculture industries have thrived: Tyson, ConAgra, Cargill
Corporation Farms
• control genetics
• control the manufacture and distribution, marketing and sales of seed (own patents on seeds), fertilizer, pesticides
• farmers receive 1 cent of 10; other 9 cents for marketing
Costs not included in retail price:
• Environmental: depletion of resources, including biodiversity of plants and animals, water, soil, fossil fuels, erosion,
• Pollution of water, soil, air: combustion, pesticides, fertilizers
• Social and economic: loss of property values, hurts small farmers
Water use• 2/3 of water use worldwide is for irrigation
• aquifers are being depleted for agriculture
Use of Chemicals
• 137 million tons of chemical fertilizers used worldwide in 1998
• ground and surface water contamination crops only use 1/3 of what’s applied
• 1600 chemicals used to manufacture pesticide; most not tested
• 3 million tons of pesticides used annually
• increased risk of reproductive, cancer, nervous system, immune problems
Costs?
• 2005 study estimates environmental and health care costs of pesticide use at recommended levels in U.S. about $12 billion annually
!
• Need to move toward a more sustainable form of agriculture
Environmental Problems from Industrialized Food Production
• topsoil erosion - farming, deforestation, overgrazing - loss of soil fertility, water pollution
• desertification -occurs when productive potential of topsoil falls by 10% or more because of drought, overgrazing, deforestation
• irrigation - as water moves - picks up salts from rocks, earth - can lead to salinization - to compensate - overwater - leads to waterlogging
More environmental problems
• air pollution - deforestation, farm equipment, livestock
• methane emissions annually have an atmospheric warming effect = 33 million cars
Environmental Problems from Meat Production
• smells!
• uses lots of fossil fuels, water
• waste - what to do with it - pollutes water - ground and surface; 130x the amount of human
• antibiotic use - 70% of all used in the US are added to animal feed