Unit 1.3 – Answers

  1. Answer: D. Life-cycle assessment is an approach to evaluating the direct and indirect effects associated with a product or activity on human health and the environment in a cradle-to-grave analysis of benefits and costs.
  2. Answer: E. The spike in food prices seen in 2007-2008, and again in 2011, were and are due to many interrelated factors, including biofuels policies that put pressure on land use and crop production systems. Nevertheless, the ‘food versus fuel’ concerns that have been voiced, and continue to be voiced, must be addressed.
  3. Answer: True. Bioenergy has the potential to be carbon-neutral by balancing the amount of carbon released in the production and use of bioenergy products with an equivalent amount put into and stored in soils, plant and animal tissues, or other material such as the ocean floor. However, there is no assurance that bioenergy will be carbon-neutral, as much depends on agricultural and industrial production practices.
  4. Answer: D. However, some researchers cauthion that conversion of marginal lands to more intensively managed bioenergy cropping systems could lead to permanent land degradation and/or increases in net GHGs.
  5. Answer: D. Options a, b, and c are possible outcomes, but not necessary outcomes. Option d is a necessary outcome, and true whether the land is utilized for production of food crops or energy crops.