科学家们发现了一个新的令人吃惊的空气污染源:养猪场和养鸡场。它们对大气造成的污染不亚于发电站排放的烟尘和废气。科学家们发现,禽畜养殖场排放的氮化物对花草树木的危害与工业污染一样严重。禽畜养殖场向空气中排放的大量氮化物——主要是 Scientists have discovered a new and surprising source of air pollution: pig farms and chicken farms. They pollute the atmosphere as much as the smoke and fumes emitted by the power stations. Scientists have found that nitrous oxide emitted from livestock farms harms plants and trees as hard as industrial pollution. Poultry farms emit large amounts of nitrogen into the air - mainly