The influence of increasing organic matter content on N2O emissions

Lynne Macdonald1, Mark Farrell1 and Jeff Baldock1

1 CSIRO Agriculture, PMB2, Glen Osmond, SA 5064, Australia (


The carbon (C) and nitrogen (N) cycles in soil are intrinsically linked.  Recently, and with particular reference to increased awareness of climatic change, there has been focus on increasing sequestration of C in agricultural soils as a potential greenhouse gas mitigation strategy.  However, increased C content in soils often also leads to an increased rate of both C and N cycling.  In the context of C accounting and defining the net greenhouse gas benefits of sequestering atmospheric CO2-C in soil, it is important to understand the potential implications of building soil C on the flux of N2O generated by N cycling processes (Zaehle et al. 2011).