Nitrogen Overdose

Inside Bay Area - Nitrogen Overdose:

I call it the biggest global change that nobody has ever heard of, Weiss said at the spring event. The planet has never seen this much nitrogen at any time. Human activity now releases 125 million metric tons of nitrogen from agricultural activities and fossil fuel combustion a year, compared to 113 million metric tons annually from natural sources, according to a 2007 United Nations report called Human Alteration of the Nitrogen Cycle.