FOOD RESOURCES

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CHAPTER 15

• FOOD RESOURCES

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How is food produced?

• Three food production systems
• croplands
• rangeland
• oceanic fisheries
• What is the good news? Food production has
  greatly increased due to 6 technological advances
• What is the bad news? Mostly over utilization of
  resources --gt environmental degradation
  increasing populations will increase the demand

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What plants and animals feed the world

• Though there is a tremendous diversity of plants
  that can be used as food, only 15 (along with 8
  terrestrial animals) supply 90 of food
• Three traditional grains - corn, rice, wheat -
  feed most people and livestock
• Fish and shellfish becoming more important

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Major types of food production

• Industrialized agriculture - uses lots of fossil
  fuel, fertilizer and pesticides
• Plantation agriculture in developing countries
• Feedlots - raising livestock in dense populations
• Traditional agriculture
• traditional subsistence - food for ones own
  family
• traditional intensive - grow food to sell

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Green Revolutions - increased food

• More food from either
• farming more land
• getting higher yields per unit area farmed
• Processes of green revolution
• plant monocultures - including genetically
  engineered high yield varieties
• use lots of fertilizer, pesticides and water
• increase intensity frequency of cropping

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Green Revolutions - increased food

• Second green revolution (since 1967)
• introduction of fast-growing dwarf varieties
• multiple cropping
• growing more food on less land
• extensive use of fertilizer, pesticides and water
• Green revolution agriculture uses 8 of worlds
  oil output

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U.S. Food Production

• Fewer farmers feed many more people
• Same amount of land is farmed - twice as much
  food is grown
• Agribusiness - agricultural system- growing,
  processing, distributing and selling food - the
  biggest industry in U.S.
• All of this depends on availability of cheap
  energy - least is used for actual growing

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Traditional agriculture - agrodiversity

• Interplanting- more than one crop/plot
• polyvarietal cultivation
• intercropping
• alley cropping
• polyculture - better use of water, less
  fertilizer required better pest protection high
  yield compared to monoculture

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World Food Problems and Challenges

• How much has food production increased?
• World grain production has almost tripled
• Average food prices have decreased
• But the bad news is that
• population growth exceeds food production which
  has declined since 1985
• many countries must import food
• vegetarian diets feed more people - but more
  people want to eat meat

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Undernutrition, Malnutrition and Overnutrition

• All three problems lead to
• lower life expectancy
• increased susceptibility to disease illness
• reduced productivity and life quality
• Undernutrition - not enough calories or
  carbohydrates, fats, proteins, vitamins or
  minerals
• Malnutrition - protein or key nutrient deficiency

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Malnutrition Undernutrition, and Overnutrition - 2

• Marasmus - diet low in calories protein
• Kwashiorkor - weaned (displaced) childs diet
  changes to one with little protein
• Number of people with chronic malnutrition is
  less than 1/2 - but malnutrition-poverty cycle
  continues
• Vitamin deficiency diseases mineral
  (specifically iron iodine) deficiencies

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Malnutrition Undernutrition, and Overnutrition - 3

• Overnutrition - food energy intake exceeds energy
  use and causes excess body fat
• 2nd leading cause of preventable deaths from
  coronary heart disease, cancer, stroke, and
  diabetes
• Meat based diets - 40 calories from fat
• If everyone lived on meatless subsistence diet,
  there would be plenty of food - but distribution
  is the problem

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Environmental effects of food production

• Agriculture has greater harmful impact on air,
  soil, water and biodiversity resources than any
  other human activity
• Low food prices do not include environmental and
  health costs
• Will improved agricultural technology feed 8
  billion people? Probably not, because much of
  land will lose it agricultural productivity

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Increasing world food production

• Expansion of green-revolution technology
• New green-revolution will be gene revolution -
  characteristics of high yield plants?
• Factors limiting success of green and gene
  revolutions
• water and fertilizer requirement
• high cost of genetically engineered crops
• local characteristics limit production these
  characteristics are being degraded

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Loss of genetic diversity

• Loss of biodiversity --gt loss of genetic raw
  material
• Large of varieties of crops are replaced by
  small of specially bred monoculture varieties
• Wild varieties must be saved, but if they have
  not evolved with their habitat, reintroduction
  may be impossible therefore must preserve
  representative ecosystems

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Will people try new foods?

• Winged bean - all parts of plant edible
• Microlivestock - 450 edible insect species
• Replace annuals with perennials
• yearly tilling and planting eliminated
• saves energy
• saves water
• reduces soil erosion

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Irrigation

• Use of irrigation is increasing but it cannot
  keep up with population growth
• Wasteful irrigation practices
• Overpumping of aquifers and chronic water
  shortages
• Need to grow crops needing less water and used
  water and grain more efficiently in livestock
  production

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Cultivate more land?

• If available unfarmed land - rainforests and
  deserts are farmed - cultivation will likely be
  unsustainable high expense to farm marginal land
  better suited for Natures purposes
• An alternative combine various ancient methods
  of shifting cultivation with fallow periods and
  various forms of polyculture

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Grow food in urban areas?

• 15 of food production now - could it be
  increased? Ghana, Singapore, China
• Recycling nutrient-rich animal and human wastes
  for food growth in urban areas reduces water
  pollution from runoff
• Wastewater-fed aquaculture of both fish and plants

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Increase fish and shellfish harvest

• Fisheries are third major food-producing system
• 70 from ocean (99 of that from coast)
• 30 from aquaculture in inland freshwater fishing
• 1/3 of fish harvest used for animal feed, fish
  meal and oils
• Recent increases in harvest not sustainable

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Increase fish and shellfish harvest-2

• Overfishing --gt loss of breeding stock can
  --gt commercial extinction (no longer profitable
  to harvest due to expense)
• 70 of worlds commercial fish stocks are
  declining 14 species may not recover
• Degradation of wetlands, estuaries, etc.
  threatens fish population
• Governments subsidize global fishing fleets

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Is aquaculture the answer?

• Fish farming - cultivating fish in controlled
  environment like pond or tank
• Fish ranching - raise and release immature fish
  harvest adults returning to spawn
• Advantages efficiency little fuel needed,
  crossbreeding and genetic engineering useful -
  yield could double
• Disadvantages - wastes --gt contamination fish
  less healthy genetically inferior

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Sustainable fishery management

• Profits must be made public
• Fair quotas must be set, monitored enforced
• Protect marine biodiversity
• Reduce of eliminate fishing subsidies
• Restrict fish farm locations and feeding
  requirements

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Government agricultural policies effects

• Because farming is financially risky government
  policy approaches
• keep food prices artificially low -farmers hurt
• give farmers subsidies to keep them farming
• eliminate most or all price controls and
  subsidies --gt market competition
• could subsidies encourage farmers to better
  protect land
• what about international food aid?

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Sustainable Agriculture

• As population grows, amount of cropland per
  person expected to decline.
• Increasing yield limited by water, genetic
  diversity limitations and degrading of land
• Two main tools to reduce food problems
• slow population growth
• develop and phase in sustainable (low-input)
  agriculture

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Can we make the transition?

• Who will oppose the changes?
• Agribusinesses
• Successful farmers with large investments in
  unsustainable forms of industrialized agriculture
• specialized farmers unwilling to learn demanding
  new practices
• But, eco-agricultural revolution could take place
  in next 30 years!