Yale Environment 360: Biofuel crops expanded onto 7 million acres of new land in the U.S. over a recent four-year period, replacing millions of acres of grasslands, according to new research from the University of Wisconsin. Using high-resolution satellite imagery, the researchers calculated that converting grasslands to croplands for corn and soy biofuels could have emitted as much carbon dioxide as 34 coal-fired power plants operating for one year, or the equivalent of an additional 28 million cars on the road. Nearly...