IEEE Spectrum June, 2013 - 40
The age of plenty
now wrest higher yields than any generation before them. They
are some of the most successful corn producers in the United
States, which grows about 40 percent of the world's corn supply.
But the big machines that extract this bounty have taken a toll
on the land. Decades of tillage and compaction have weakened
the soil, making it prone to heavy erosion from wind and rain.
Agronomists estimate that since large-scale farming began here
about 150 years ago, Iowa has lost roughly half its topsoil. In the
mid-19th century, the average farmer could dig a hole in his field
and stick his arm in as deep as the elbow before he felt something other than black, nutrient-rich earth. Today, he's lucky if he
gets as far as his wrist. Recent measurements show that in many
parts of the state, topsoil is washing away 10 to 50 times as fast
as it can re-form. There is evidence that such rapid degradation
is already depressing yields.
What's happening in Iowa isn't unique. Studies suggest that
every year, one hectare of farmland anywhere on Earth loses on
average 30 metric tons of soil-enough to fill a large shipping container. In some places, erosion has degraded farmland so severely
40
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SPectrum.ieee.orG
PreCIsIon BY
that it has been abandoned. As the world's
sATeLLITe:
population rises, farmers are faced with
real-time
having to grow more crops on less soil.
kinematic GPs
receivers let Clay
"Globally, we are on the fringe of not being
Mitchell tend to his
able to meet the food demand that exists
crops with centitoday," says Richard Cruse, a professor of
meter accuracy.
agronomy at Iowa State University.
Yet there may be reason for hope. A new
tech-driven trend-some even say revolution-in agriculture is
beginning to take hold in Iowa and in many parts of the world.
Known as precision agriculture, the practice promises to reconcile mass food production with responsible land stewardship. It
is perhaps best summed up by the oft-cited mantra "Doing the
right thing, at the right place, at the right time, in the right way."
The concept harks back to agriculture's early days, when a
farmer, working by hand, could give each plant the exact amount
of nutrients, water, weeding, and pest killing it needed without
disturbing the soil very much. That era is long gone. But now
information and communications technologies are bringing it
PhoToGrAPhs, PrevIous PAGes And ThIs PAGe, BY
gregg segal
http://SPectrum.ieee.orG
Table of Contents for the Digital Edition of IEEE Spectrum June, 2013
IEEE Spectrum June, 2013 - Cover1
IEEE Spectrum June, 2013 - Cover2
IEEE Spectrum June, 2013 - 1
IEEE Spectrum June, 2013 - 2
IEEE Spectrum June, 2013 - 3
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IEEE Spectrum June, 2013 - 85
IEEE Spectrum June, 2013 - 86
IEEE Spectrum June, 2013 - 87
IEEE Spectrum June, 2013 - 88
IEEE Spectrum June, 2013 - Cover3
IEEE Spectrum June, 2013 - Cover4
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