With a population set to hit 9
billion human beings by 2050, the world needs to grow more food —without
cutting down forests and jungles, which are the climate's huge lungs.
The solution, according to one soil management scientist, is Big Data.
Kenneth Cassman,
an agronomist at the University of Nebraska, Lincoln, recently unveiled
a new interactive mapping tool that shows in fine-grain detail where
higher crop yields are possible on current arable land.
"By some estimates, 20
to 30 percent of greenhouse gas emissions are associated with
agriculture and of that a large portion is due to conversion of natural
systems like rainforests or grassland savannahs to crop production,
agriculture," Cassman told NBC News at a conference in suburban Seattle.
The only practical way
to stop the conversion of wild lands to farmland is grow more food on
land already dedicated to agriculture, he said. Currently, the amount of
farmland used to produce rice, wheat, maize and soybean, he noted, is
expanding at a rate of about 20 million acres a year.
Cassman and colleagues unveiled the Global Yield Gap and Water Productivity Atlas in October at the Water for Food
conference. The atlas was six years and $6 million in the making and
contains site-specific data on soil, climate and cropping systems to
determine potential yield versus actual yield farm by farm in nearly 20
countries around the world. Projects are ongoing to secure data for 30
more countries.
Mind the gap
Once
farmers are aware of their gaps, they can prioritize investments to
close them, such as spending on fertilizer, a new irrigation system or
different crop varieties. When scaled up to a global view, a seed
company can look at the map and see where drought routinely curbs
yields, for example, and target research, development and marketing of
drought-tolerant varieties on those regions.
The tool is likely to
be especially helpful to major agribusiness companies such as Syngenta
and Monsanto, which were major sponsors of the conference where the
atlas was unveiled, said Danielle Nierenberg, president of Food Tank, a Washington-based advocacy for sustainable agriculture.
"That is not
necessarily a bad thing, but if information isn't getting down to the
500 million family farmers around the world who are producing most of
the world's food, more than 50 percent of the world's food, then I don't
see the point. Those farmers have to make a profit too and feed their
families," she said.
TIM WIMBORNE / Reuters file
Atlas in action
A
key initiative going forward is to teach smallholder farmers how to use
the atlas, Cassman said. Until now, the tool has largely rested with
agricultural researchers who have validated its promise of delivering
information that can help grow more food on existing farmland.
At the Water for Food conference, for example, agricultural researcher Zvi Hochman
with Australia's Commonwealth Scientific and Industrial Research
Organization described how he used the atlas to compare his country's
wheat yields with those in similar climate zones around the world. A
colleague noted overlap with Argentina, where yields are higher.
To figure out the
difference in yield, Hochman dug into the data and learned that
Argentinean farmers grow wheat and corn on the same fields each year. He
then explored scenarios for growing two crops a year in Australia.
That's "a system," he said, "that is not currently practiced by most
farmers." A winning strategy for Australia, he concluded, is to grow
lentils after wheat in years with sufficient water.
Likewise, Kindie Tesfaye,
a researcher with the International Maize and Wheat Improvement Center
in Ethiopia, described how he used the atlas to determine that by
closing the yield gap a feasible 50 percent in Ethiopia, the country
could grow enough cereals to feed 205 million people by 2050, which is
greater than the United Nation's projected growth in population to about
174 million.
To close the gap by
that much, he added, more research is needed to understand "the
biophysical and the socioeconomic constraints that are leading to these
yield gaps." That is, the atlas is a first step, a road map to boosting
yields.
"It allows us to be
able to pinpoint where the big gaps are and to start to gather the
pieces of the puzzle to say, well, why is it that we have the yield gaps
in those particular points," Robert Lenton,
the founding director of the Water for Food Institute at the University
of Nebraska, said during a press briefing at the conference.
Barry Malone / Reuters file
Closing the gaps
One
key breakthrough is the global boom in natural gas, according to
Cassman. Its abundance and thus lower cost, he said, makes
natural-gas-derived fertilizers and energy for pumping water accessible
and available in a way they were not just seven years ago. As a result,
for the first time in at least 40 years, he said, the value of crops
grown is rising faster due to insatiable demand than the cost of inputs.
"In closing yield gaps
in many parts of the world, particularly sub-Saharan Africa, the biggest
constraints are nutrients and water," he said. "And if the cost of
accessing external resources to alleviate those constraints on your
farm, if that's decreasing relative to the value of what you produce,
then at least the economic incentive to use those inputs becomes
greater. And it wasn't that way in the past."
Cheap natural gas, he
said, increases the economic incentive to use those inputs and grow more
food. And enough food to meet the demand for more meat and sugar in an
increasingly wealthy world, he said, is necessary to alleviate poverty,
stabilize population and curb climate change.
"Indirectly, if we
don't have access to reasonable supplies of energy then you don't reduce
poverty fast enough to stabilize human population at 9.6 (billion) and
you zoom past it and then your challenge for climate change and land
clearing become exorbitantly larger," Cassman said. "I think that is
what people are missing in the connections."
The need to close yield gaps is reinforced by a study released Monday in Nature Climate Change
on the challenge of implementing a forest conservation policy. If
non-forested areas aren't protected as well, the study found,
agriculture will expand into grasslands and other areas that also store
carbon, leading to carbon emissions that essentially offset those gained
by saving the forests.
A more robust policy is
to globally protect native forests and non-forested areas such as
grasslands, according to study lead author Alexander Popp at the Potsdam Institute for Climate Impact Research in Germany.
"That would mean this
loss of potential land for agricultural expansion, which has to be
compensated for by increasing yield," he told NBC News.
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