ScienceAlert Homepage

Greenhouse gases are not only emitted by industry, cars or households. In addition to carbon dioxide, other greenhouse gases are emitted by soils as part of the natural cycling of nutrients and decomposition. These so called non-CO2 greenhouse gases are more potent than carbon dioxide with regard to global warming, and already make up one quarter of Australia’s greenhouse gas emissions.

Researchers at the University of Melbourne are holding a conference on the importance of soil based greenhouse gas emissions in Melbourne from May 15 to 16. Dr Steve Livesley, Dr Stefan Arndt and Dr Richard Eckard from the Faculty of Land and Food Resources have invited experts from all over Australia and New Zealand to discuss the importance of greenhouse gas emissions from soils.

“Nitrous oxide, for example, is 300 times more potent than CO2, so even small emissions of this non-CO2 gas can make a considerable contribution to global warming” says Dr Stefan Arndt.

The non-CO2 greenhouse gases are particularly important in agriculture. “When nitrogen is added to a wheat field as fertilizer or added to a pasture through animal faeces or clover swards, a part of the nitrogen can be lost as nitrous oxide, and when the weather conditions are right this can lead to large emissions of nitrous oxide” says Dr Eckard.

Grazing animals themselves emit the non-CO2 greenhouse gas methane, however it is not widely known that soils can actually offset some of those methane emissions by taking methane out of the atmosphere. “Forest soils are especially efficient at taking up methane” says Dr Livesley.

At the present time there is not much knowledge about the magnitude of these non-CO2 emissions, the processes that control them and the possible strategies to lower these emissions. “We have made significant research progress in Australia and New Zealand in the last few years and it is time to discuss the new results in a conference” says Dr Arndt. “We will be able to share and assess current research achievements and discuss future research needs. We will also discuss appropriate strategies to lower these emissions in Australian and New Zealand landscapes.”