Page 267 - Environment: The Science Behind the Stories

The effects of these developments on the environment
have been mixed. On the positive side, the intensified use of
already-cultivated land reduced pressures to convert addi-
tional natural lands for new cultivation. Between 1961 and
2010, food production more than tripled and per-person food
production rose 48%, while area converted for agriculture
increased only 10%. In this way, the Green Revolution pre-
vented some degree of deforestation and habitat conversion
and thus helped preserve biodiversity and natural ecosystems.
On the negative side, the intensive application of water, fossil
fuels, inorganic fertilizers, and synthetic pesticides worsened
pollution, topsoil losses, and soil quality (Chapter 9).
The planting of crops in monocultures, large expanses Figure 10.7 Monocultures improve the efficiency of planting
of single crop types (p. 236; Figure 10.7), makes planting and harvesting but are susceptible to outbreaks of pests.
and harvesting more efficient and thereby increases output. Armyworms (inset) may attack this wheat field in Washington.
However, monocultures also reduce biodiversity over large
areas, because many fewer wild organisms are able to live in low-income farmers who could not afford these technologies
monocultures than in native habitats or in traditional small- were driven out of business and moved to cities, adding to the
scale polycultures. Moreover, when all plants in a field are immense migration of poor rural people to urban areas of the
genetically similar, as in monocultures, all are equally suscep- developing world (p. 355).
tible to viral diseases, fungal pathogens, or insect pests that
can spread quickly from plant to plant. For this reason, mono-
cultures bring risks of catastrophic failure. Some biofuels reduce food supplies
Monocultures also contribute to a narrowing of the human Just as the Green Revolution’s noble intentions and signifi-
diet. Globally, 90% of the food we consume now comes from cant successes gave rise to some problematic side effects, in
just 15 crop species and eight livestock species—a drastic recent years some well-intentioned efforts to promote renew-
reduction in diversity from earlier times. Such dietary restric- able energy have had unintended consequences. Biofuels
tion carries nutritional risks. Fortunately, expanded global (pp. 585, 587–588) are fuels derived from organic materials
trade has provided access to a wider diversity of foods from and used in internal combustion engines as replacements for
around the world, although this has benefited wealthy peo- petroleum. In an effort to shift from fossil fuels to renewable
ple more than poor people. One reason farmers and scientists energy sources, policymakers have encouraged the produc-
are so concerned about transgenic contamination of southern tion of biofuels from crops. In the United States, ethanol
Mexico’s native maize is that Mexican maize varieties serve made from corn is the primary biofuel (pp. 587–588). Fol-
as valuable sources of genetic variation in a world where so lowing expanded subsidies in 2007, U.S. ethanol production
much variation is being lost. nearly doubled as new ethanol facilities opened and farmers
Today, yields are declining in some Green Revolution began selling their corn for ethanol instead of for food.
regions, likely due to soil degradation from the heavy use This caused a scarcity of corn worldwide, and prices for
of fertilizers, pesticides, and irrigation. Moreover, wealth- basic foods (such as tortillas in Mexico) skyrocketed. Prices
ier farmers with larger plots of land were best positioned to for other staple grains also rose because farmers shifted fields
invest in Green Revolution technologies. As a result, many
formerly devoted to other food crops into biofuel produc-
tion. For low-income people, the steep rise in food prices was
WeIGhING the IssUes frightening. Thousands staged protests, and riots erupted in
Mexico and many other nations. The world realized that grow-
the GReeN ReVOlUtION ANd POPUlAtION In the 1960s, ing crops for biofuels could compete directly with growing
India’s population was skyrocketing, and its traditional food for people to eat. Scientists today are trying to develop
agriculture was not producing enough food to support the ways of producing biofuels from crop waste and other non-
growth. By adopting Green Revolution agriculture, India food material (pp. 589–590).
sidestepped mass starvation. However, Norman Borlaug
called his Green Revolution methods “a temporary success in
man’s war against hunger and deprivation,” something to give We are moving toward sustainable
us breathing room to deal with what he called the “Population agriculture
Monster.” Indeed, in the years since intensifying its agriculture,
India has added several hundred million more people and Industrial agriculture has enabled food production to keep
continues to suffer widespread poverty and hunger. pace with our growing population thus far, but it also brings
Do you think the Green Revolution has solved problems, many adverse environmental and social impacts. Industrial
deferred problems, or created new ones? Which aspects of agriculture in some form seems necessary to feed our planet’s
the Green Revolution do you think help in the quest for sustain- 7 billion people, but most experts feel that to sustain our popu-
ability, which do not, and why? Have the Green Revolution’s lation in the long run we will need to begin raising animals
and crops in ways that are less polluting and less resource-
266 benefits outweighed its costs? intensive.

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