Decisions You’ll Make
The same applies to questioning the productivity of American agri-
culture. Over the last several decades, to turn out more food we have
relied heavily on more fertilizer, chemicals, water, monoculture crops,
and concentrated animal feeding operations. Using more to produce
more without questioning what comes afterward is hardly a recipe for
a sustainable food system.
Because what goes up invariably comes down, food productivity
will eventually fall. A more technical term to describe this transition
is peak-rate, which also serves as an indicator of sustainability. As the
modern food system expands internationally, what happens at the global
level takes on added importance. For crucial staple foods like wheat,
for example, peak-rate indicates that wheat harvests will next plateau,
and then decline. Recently, researchers looked at whether the peak-
rates for major foods and related resources at the global level were in
decline. For fifteen of the sixteen most common staples like dairy, eggs,
seafood, meat, poultry, soybeans, wheat, and corn, the answer was yes.
For related resources like land to grow crops, water to irrigate those
crops, and nitrogen to provide nutrients, the answer was also yes.
While the environment’s role in food availability is irreplaceable,
such importance is seldom acknowledged. Over time, shifts in the
environment have led to mass extinction of species. Five such extinc-
tions have occurred, caused by meteor strikes, volcanoes, and natural
climate. Today, we are experiencing the sixth mass extinction. But unlike
the previous five, this one is due to heat-trapping molecules in the at-
mosphere from burning fossil fuels.
Extinction rates always vary by species and changes to habitat.
As the planet warms, weeds, insects, and parasites are fanning out
geographically. As they spread, entire ecologies of needed microbes,
beneficial insects, food plants, and food animals are threatened. When
habitats that once supported life begin to perish, genetic diversity falls
and traits that gave us greater yields at harvest, resilience to weather, or
resistance to pests and competitors are at risk of being lost. Nutrients like
zinc and iron in grains and legumes decline. Food plants and animals,
already weakened by higher stress as temperatures rise, succumb to the
growth and attacks of bacteria that have more readily adapted.
Productivity, peak-rate, and mass extinction pose enormous chal-
lenges. Yet there exists an even more ominous threat—apathy on our