NPR : News

Heavy Rains Send Iowa's Precious Soil Downriver

What a difference a year makes. Last year at this time, the Midwest was heading into one of the worst droughts in decades. Now much of the region is soggy.

But the biggest loser from this year's heavy rains? The land itself.

The Environmental Working Group, drawing on analysis done by Iowa State University's Iowa Daily Erosion Project, found in a recent report that during one five-day period in May, 50 townships in Iowa lost more than five tons of topsoil per acre.

As EWG puts it: "Those 1.2 million acres of farmland may have lost more precious topsoil in five days than what is tolerable over an entire year." The U.S. Department of Agriculture's Natural Resources Conservation Service considers an annual rate of topsoil loss of five tons "tolerable," but EWG says "a truly sustainable rate of erosion is far lower."

As Abbie Fentress Swanson reported last week, the lost topsoil contains a huge amount of nutrients, like nitrogen and phosphorus, that are essential for growing crops. Once they enter rivers, lakes and bays, they can trigger algal growth.

Several members of EWG's Iowa-based staff took a road tour of the damage. You can browse photos that they took along the way on an interactive map.

According to EWG, much of the soil loss could be prevented through more aggressive soil conservation practices, including "no-till" planting, grass waterways and terraces. "Every no-till field with properly placed grass waterways showed only nominal signs of erosion," says the report. "Well-protected fields suffered little damage even where poorly protected fields just down or across the road had suffered badly."

Copyright 2013 NPR. To see more, visit http://www.npr.org/.

NPR

Comic-Con Fans Continue The Epic Battle Between Science And Fiction

Fans of science fiction have long wrestled with the question of just how much science should be in their fiction. Advocates of different approaches met at San Diego's Comic-Con.
NPR

Scraped, Splattered — But Silent No More. Finally, The Dinner Plate Gets Its Say

Instagram is the Internet's semi-obsessive, borderline-creepy love letter to food. But behind every great meal is a plate doing a pretty-OK job. So a comedian made an Instagram to celebrate plates.
NPR

Leaked Democratic Party Emails Show Members Tried To Undercut Sanders

Just days before the Democratic National Committee convention gets underway, WikiLeaks releases almost 20,000 emails among DNC staff, revealing discussions of topics from Bernie Sanders to the media.
NPR

Making The Cloud Green: Tech Firms Push For Renewable Energy Sources

Few people can demand what kind of electricity they get. But Microsoft and Facebook, which operate huge, power-hungry data centers, are trying to green up the electricity grid with their buying power.

Leave a Comment

Help keep the conversation civil. Please refer to our Terms of Use and Code of Conduct before posting your comments.