Page 291 - Environment: The Science Behind the Stories

Testing Your Comprehension

1. What was the Green Revolution, and what impact did it 6. Explain the concept of biocontrol. List several compo-
have on developing countries? Discuss the impact of the nents of a system of integrated pest management (IPM).
Green Revolution on the environment. 7. Define organic agriculture, and describe what a farmer
2. Explain the statement “the lower down in the food chain must do to get his or her food certified as organic. What
we eat, the greater percentage of solar energy we put to factors are driving the growth of organic agriculture?
use, and the more people Earth can support” in terms of 8. What is recombinant DNA? How is a transgenic organ-
trophic levels and pyramids of energy. ism created? How is genetic engineering different from
3. What are some economic benefits of aquaculture? What traditional agricultural breeding? How is it similar?
are some negative environmental impacts? 9. Describe several reasons why many people support the
4. About how many and what types of cultivated plants are development of genetically modified organisms, and
known to rely on insects for pollination? Why is it impor- name several uses of such organisms that have been
tant to preserve the biodiversity of native pollinators? developed so far.
5. Why is resistance to pesticides likely over time when they 10. Describe the scientific concerns held by opponents of
are used in agriculture? GM crops. Describe some of their other concerns.

Seeking Solutions

1. Assess several ways in which high-input industrial agri- do you think is warranted before a new GM crop is
culture can be beneficial for environmental quality and introduced?
several ways in which it can be detrimental. Now suggest 5. THINK IT THROUGH You are a USDA official and must
several ways in which we might modify industrial agri- decide whether to allow the planting of a new genetically
culture to mitigate its environmental impacts. modified strain of cabbage that is tolerant to a best-sell-
2. Describe two fundamental approaches for preserving the ing herbicide and has twice the vitamin content of regu-
genetic diversity of crop variants. Give a specific example lar cabbage. What questions would you ask of scientists
of each approach. What benefits and risks do you see in before deciding whether to approve the new crop? What
each approach? scientific data would you want to see? Would you also
3. What factors make for an effective biological control consult nonscientists or consider ethical, economic, and
strategy of pest management? What risks are involved in social factors?
biocontrol? If you had to decide whether to use biocontrol 6. THINK IT THROUGH You are a farmer in the U.S. Mid-
against a particular pest, what questions would you want west, own 1000 acres, and intend to farm corn for a liv-
to have answered before you decide? ing. Would you choose to grow genetically modified corn?
4. People who view GM foods as solutions to world hun- How would you manage pests and weeds? Would you grow
ger and insecticide overuse often want to speed their corn for people’s food, livestock feed, or biofuels? Think
development and approval. Others adhere to the pre- of the various ways corn is grown, purchased, and valued
cautionary principle and want extensive testing for in different places—such as the United States, Europe,
health and environmental safety. How much caution and southern Mexico—as you formulate your answer.

Calculating Ecological Footprints

Many people who want to reduce their ecological footprint shelves, and this transport consumes oil. This concern over
have focused on how much energy is expended (and how “food-miles” has helped drive the “locavore” movement to
many climate-warming greenhouse gases are emitted) in buy and eat locally sourced food.
transporting food from its place of production to its place of However, food’s transport from producer to retailer, as
sale. The typical grocery store item is shipped by truck, air, measured by food-miles, is just one source of carbon emis-
290 and/or sea for many hundreds of miles before reaching the sions in the overall process of producing and delivering food.

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