5 May 2010

The global market for sugarcane is expanding, and new research at UQ is providing clues as to how improved farming practices will reduce the environmental footprint of sugarcane farming.

In the study, a UQ team in collaboration with Department of Environment and Resource Management analysed greenhouse gas emissions from an experimental sugarcane farm near Jacobs Well, 45km south east of Brisbane.

Emissions of nitrous oxide (N2O) from soil increased when "higher-than-recommended" rates of nitrogen fertiliser were applied. Nitrous oxide is a potent greenhouse gas which has a global warming potential 300 times higher than carbon dioxide, the Earth’s most problematic climate warmer.

"Nitrous oxide in the atmosphere originates mostly from nitrogen stored in the soil. Globally, the concentrations of nitrous oxide in the atmosphere are increasing and contributing to global warming. Much of the recent increases in atmospheric N2O originate from modern farming systems," said Dr Susanne Schmidt from the School of Biological Sciences.

"Our study demonstrates that N2O emission from sugarcane soil can be significantly reduced with appropriate management. The sugar industry has been pioneering new approaches, and our findings provide scientific confirmation of the value of these initiatives.

"Sugarcane growers, who reduce the application of nitrogen fertiliser, reduce emissions. Avoiding accumulation of soluble nitrogen in the soil, the precursor for N2O, and preventing water-logging through irrigation, strongly reduces emissions.

"Growers are aware that sustainable practices are key to future productivity and efficiency. Significant initiatives have been pursued by the industry in addressing environmental issues and adopting sustainable farming practices. Nitrogen fertiliser application rates have been dramatically lowered the last few years and we are seeing the benefits. The knowledge generated in our study provides further guidance to curb greenhouse gas emissions."

Media: Associate Professor Susanne Schmidt (3365 1050, Susanne.Schmidt@uq.edu.au ) or Tracey Franchi, Manager – Communications, Outreach and Performance Data in the School of Biological Sciences (3365 4831, t.franchi@uq.edu.au).