Tufts OpenCourseware
Author: Colin Orians

1. Discussion Questions

1.1. Chapter 9

1.1.1. Sustainability

  • What would constitute sustainability? What agricultural methods would maximize sustainability?
  • What constraints often inhibit the implementation of sustainable agriculture techniques? If farmers use industrial inputs (fertilizers, pesticides, herbicides, mechanization), does that mean it is not sustainable?

1.1.2. Genetic Variation

  • Are local varieties of crops from traditional agricultural systems useful in breeding programs?
  • Is genetic engineering the solution to improved crops?
  • We have talked about the importance of local adaptation in this course. Does industrial seed production work against local adaptation?

1.1.3. Risks – Temperate vs. Tropical

  • Which economic and environmental risks are connected with industrial agriculture in tropical areas? Are these risks the same as in temperate areas?
  • Is weed control a greater problem in tropical than in temperate agricultural systems? If so, describe. Discuss options for weed control.

1.1.4. Pest Pressures

  • Compare pest pressure on natural plant communities and agricultural crops. By which mechanisms can crop rotations and polycultures provide pest control?
  • On theoretical grounds, polycultures are thought to limit pest pressures. Compare and contrast the “resource concentration” hypothesis and the “natural enemies” hypothesis.

1.1.5. Nutrients

  • Which nutrients have to be replaced more frequently by farmers in tropical regions?
  • What can farmers due to maximize the retention of these nutrients?

1.1.6. Soil Erosion

  • What conditions tend to maximize soil erosion? How can it be mitigated? Why is agroforestry thought to limit erosion?