The impact of anthropogenic nitrogen deposition on global forests: Negative impacts far exceed the carbon benefits.

Abstract

Humans have drastically altered the nitrogen (N) cycle during the past century, enriching ecosystems from the tropics to the tundra with unpresented inputs of novel nitrogen. The study by Schulte-Uebbing et al. (2021) quantified the impact of atmospheric N deposition on C uptake by forests globally, and weighed this climate benefit against the global warming impact of N2 O emissions. A major conclusion was that the C benefits of atmospheric deposition in global forests are smaller than previously estimated (only 41TgCyear-1 ), accounting for only 2% of the net annual forest C uptake.