The Midwest’s Corn Fields Are Even Worse for the Planet Than We Thought

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 U.S. 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 it leaches into streams. And some of that escaped nitrogen, too, transforms into nitrous oxide.

Read more at The Midwest’s Corn Fields Are Even Worse for the Planet Than We Thought