Effective management practices to reduce nitrous oxide emissions from sugarcane soils. Ingham and Bundaberg, Queensland, 2012-2015 [Theme 5: Reducing emissions through improved NUE]

High nitrous oxide (N2O) emissions have been observed in previous field studies in Australian sugarcane cropping systems. These observations demonstrate a genuine need and great potentials for developing effective mitigation strategies. In this project, we are using a combination of automatic gas sampling systems and manual chambers to investigate effective management practices for reducing N2O emissions in the wet tropical and subtropical sugarcane production regions.

The major objectives of this project were to (i) investigate the efficacy of DMPP and polymer coating on mitigating N2O emissions, reducing N fertiliser application rates and increasing fertiliser N use efficiency whilst maintaining or enhancing crop yield in the wet tropics where normal fertiliser N is susceptible to losses by denitrification, leaching and runoff; and (ii) identify better soybean residue management practices for mitigating N2O emissions and maximising N use efficiency in the subtropics where leguminous crop rotation is recommended as one of the sustainable management practices in future farming systems.

To address objective 1 a field experiment was setup near Ingham, in northern Queensland, while another field experiment was setup near Bundaberg in Queensland, to address objective 2.