Arizona State University Green Revolution in Agricultural System Discussion

• Describe what is meant by the “green revolution” in agricultural systems. How has this revolution allowed modern human civilization to avert a Malthusian outcome over the twentieth and early twenty-first centuries? But why is agriculture also recognized as a primary driving force for global environmental problems like habitat destruction, cultural eutrophication, water scarcity, and soil contamination? Discuss at least two ways in which specific kinds of genetically modified organisms (GMOs) could credibly reduce the environmental impacts of modern agricultural systems. Use supporting evidence to back up your argument. Then discuss at least two credible lines of argument, with supporting evidence, that raise environmental concerns about specific GMO-based agricultural practices. (25 points)
• What does Dr. Evans mean by the term anthro-hydrologic cycle? Describe what is meant by “consumptive use” of a water resource and discuss how a consumptive use differs from a “non-consumptive use” in terms of impacts upon a water supply source. What is the primary consumptive use associated with long-term declines in Volusia Blue Spring? (12.5 points)
• Describe the process of cultural eutrophication, including detailed descriptions about the roles of phosphate/phosphorus, nitrogen (NO_x and NH₃/NH₄⁺), oxygen (O₂), and organic carbon in the cultural eutrophication process. What is the difference between point source and non-point source pollutants? Why are non-point pollutant sources currently more important that point source pollutants in terms of driving continued cultural eutrophication in the United States? (25 points)
• Describe the three major fossil fuel energy sources, including how they are extracted and used within modern society. What are four key attributes of fossil fuels that have historically made them such an attractive and dominant source of energy? Discuss two specific environmental concerns that accompany “tight oil” production, and also discuss why “tight oil” is not nearly as economically (or, hint, energetically) efficient as traditional oil production (12.5 points).
• Wind, solar, and biomass/biofuels are three of the most prominent renewable energy sources and use of these resources is expected to continue growing over the next several decades. What are key advantages associated with each of these energy sources in terms of a transition away from our current fossil fuels-based economy. (Provide at least two “advantages” for each of these alternative energy sources.) Next, discuss key challenges that historically have made fossil fuels more economically and technologically competitive than these alternative energy sources. Finally, describe a plausible scenario for an electric power grid in DeLand, FL, that is entirely run by some mixture of wind, solar, and biomass energy in the year 2050. Use plausible evidence/arguments from your text, lectures, and other supplementary materials to construct this scenario. (25 points)
• As discussed in class and in your textbook, mosquito control remains one of the most world’s most important – and contentious – environmental health issues. Briefly describe how the insecticide DDT was used in the United States and other developed nations during the 1940s and 1950s. Then discuss how the bioaccumulation and biomagnification of DDT, as famously highlighted in Rachel Carson’s book Silent Spring, impacted birds of prey and other species at the top of food chains.

As noted in class lecture and discussion, these environmental impacts resulted in DDT use being mostly discontinued everywhere in the world by the mid-1990s. But why did some international health organizations started recommending renewed use of DDT for “indoor residual spraying” in the early to mid-2000s. Based on the lectures, text, and supplementary readings you have had for this class, do you think that the benefits of “indoor residual spraying” of DDT are likely to outweigh the potential harms to human health and the natural environment? Why or why not? (Use good evidence to support your argument.)