Nitrogen levels in the soil, water and atmosphere have increased fivefold globally in the past 60 years – largely due to human activities in the agricultural sector, according to a new study. Too much nitrogen can affect human health, reduce biodiversity and amplify global warming.
Humans have put an unprecedented amount of nitrogen into the earth
"Just as carbon fueled the Industrial Revolution, nitrogen has fueled an Agricultural Revolution," the study authors wrote. "The use of synthetic nitrogen fertilizers and the cultivation of nitrogen-fixing crops both expanded exponentially during the last century, with most of the increase occurring after 1960."