5.3

• The Green Revolution:

  • The shift in agriculture away from small, family operated farms to large, industrial scale agribusinesses
  • Increased use of mechanization, GMOs, irrigation,, fertilizers, and pesticides
  • Decreased world hunger and increased earth's carrying capacity
  • Negative consequences: soil erosion, decreased biodiversity, ground/surface water contamination
• Mechanization: increased use of tractors for plowing and tilling fields & combines for harvesting led to increased yields + profits

  • Increased reliance on fossil fuels
  • Emits GHGs to atmosphere
  • Heavy machinery compacts soil, decreasing water holding capacity
  • Makes topsoil more prone to erosion
• GMOs: genetically modified crops that could have genes for drought tolerance, pest resistance, faster growth,and larger fruit/grain

  • Decreased genetic diversity and higher susceptibilty to disease/pest
• Synthetic fertilizer: shift from organic fertilizers (manure/compost) to man made (ammonium, nitrate, phosphate)

  • Increases yield and profits
  • Excess nitrates, phosphates are washed off fields and into nearby water sources; can lead to eutrophication
  • requires fossil fuels for production, releasing CO2
• Irrigation: drawing water from the ground or nearby surface waters and distributing it on fields to increase plant growth

  • Makes agriculture possible in many parts of the world that are naturally too dry
  • Can deplete groundwater resources especially aquifers
  • Over-watering can drown roots & cause salinization (increase salt level in soil)
• Pesticides: increased use of synthetic pesticides (chemicals sprayed on crops to kill weeds, insects, rodents, and other pests that eat or damage soil)

  • increases yield and profits with fewer plants lost to pests
  • can wash off crops and kill/harm non-target pests in local soil/water
  • endocrine disruption