clipped from environment.newscientist.com Nitrogen pollution drives trees to soak up more CO2 Nitrogen pumped into the environment by human activities such as driving cars and farming is fertilising tree growth and boosting the amount of carbon being stored in forests outside the tropics, say researchers. Their study provides a surprising example of how one type of human pollution is helping to counter another. But the researchers caution that they do not yet know what proportion of carbon dioxide emissions are being offset by the anthropogenic release of nitrogen.