corn

How the Midwest’s Corn Farms Are Cooking the Planet

PNAS
June 26, 2015

As if we needed another reason to rid the world of millions of acres of pesticide-drenched GMO corn—about 85 percent of which is used to make ethanol fuel or feed animals on factory farms.

As it turns out, nitrogen fertilizer doesn’t just pollute water, as the people in Toledo, Ohio, learned the hard way, when their water became so polluted the city had to shut it off. A large portion of the nitrogen in agricultural fertilizer, according to a new study, escapes into the atmosphere as nitrous oxide—a greenhouse gas greenhouse gas with nearly 300 times the heat-trapping power of carbon dioxide, as reported in a recent article in Mother Jones.

According to Tom Philpott, reporting on a new study by a team of researchers from the University of Minnesota, Yale, and the U.S. Department of Agriculture (USDA), when researchers measured nitrous oxide emissions at 19 streams over a two-year period in southeastern Minnesota, they found that “standard greenhouse gas emission measures, such as those used by the Intergovernmental Panel on Climate Change (IPCC), have been undercounting these ‘riverine’ emissions sources by a factor of nine; and overall N2O emissions from the area are underestimated by about 40 percent.”

Should you stop eating corn? Yes, if it’s in the form of GMO high fructose corn syrup. And we should all stop eating meat or cheese, or drinking milk, that came from animals fed GMO corn. But the problem isn’t with corn itself, if the corn is grown from non-GMO seeds, using organic regenerative farming practices. The problem is with how we grow most of the world’s corn today—and how much of it we grow that way.

Read the Full Study

 

2015-08-27T16:28:00+00:00

corn

How the Midwest’s Corn Farms Are Cooking the Planet

Tom Philpott
Mother Jones
August 12, 2015

I’ve been thinking a lot recently about how fertilizer from the Midwest’s big corn farms seeps into streams and causes trouble—fouling water supplies in Columbus, Toledo, Des Moines, and 60 other towns in Iowa, and generating a Connecticut-sized dead zone at the heart of the continental United States’ most productive fishery, the Gulf of Mexico. (Farms in the region also plant soybeans, but corn is by far the bigger fertilizer user.) But there’s another way the Corn Belt’s fertilizer habit damages a common resource: by releasing nitrous oxide (N2O), a greenhouse gas with nearly 300 times the heat-trapping power of carbon dioxide.

It turns out that the region’s farms are likely generating much more nitrous oxide than scientists previously thought, according to a new peer-reviewed study by a team of researchers from the University of Minnesota, Yale, and the US Department of Agriculture.

Scientists had assumed that most nitrous oxide emissions from farming occurred at the soil level—some of the nitrogen fertilizer applied onto farmland vaporizes into nitrous oxide. But as citizens of Des Moines, Columbus, and the Gulf coast know well, nitrogen fertilizer doesn’t stay in soil; a portion of its leaches into streams. And some of that escaped nitrogen, too, transforms into nitrous oxide.

To measure how much, the team, led by University of Minnesota researcher Pete Turner measured N2O emissions at 19 streams over a two-year period in ag-intensive southeastern Minnesota. They found that standard greenhouse gas emission measures, such as those used by the Intergovernmental Panel on Climate Change (IPCC), have been undercounting these “riverine” emissions sources by a factor of nine; and overall N2O emissions from the area are underestimated by about 40 percent.

While they only took measurements in one small part of the US Midwest, the researchers write that other regions of the globe have similar conditions: large swaths of land dominated by fertilizer-intensive farming. Such areas include the rest of the US Corn Belt plus parts of China, Europe, and India. These industrial-scale farming regions, which together make up a landmass of about 580 million acres (nearly six times the size of California), are the globe’s most potent sources of nitrous oxide, and we’re likely drastically undercounting their total emissions, the study suggests.

2015-08-12T16:47:00+00:00