ABSTRACT
As the third most important anthropogenic greenhouse gas and the largest remaining anthropogenic stratospheric ozone depleting substance currently emitted, nitrous oxide (N2O) is one of the most important forms of nitrogen (N) pollution (Ravishankara et al 2009, Ciais et al 2013). Excess N pollution has been identified as one of the three global environmental issues whose ‘planetary boundary’ has been surpassed (Rockström et al 2009). Once an N atom is in a reactive form, it can contribute to a number of cascading environmental problems as it is transported through terrestrial and aquatic ecosystems and into the atmosphere (Galloway et al 2003). Effective mitigation for N2O emissions requires understanding of the sources and how they may increase this century.
