Two of the desired mitigation outcomes for Australian horticulture are further reduced greenhouse gas emissions from horticultural production systems, and profitable horticultural production systems which contribute to greenhouse gas abatement.

Agriculture in Australia was responsible for 16.5 per cent of Australia’s GHG emissions in 2004 - making it the nation’s second largest emitter (after energy sector). Agricultural activity can influence the atmospheric level of three of the major greenhouse gases - carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) - both as a source and a sink. See here for more information

The Australian agricultural and land use sectors have already made a significant contribution towards Australia’s commitment to reduce its greenhouse gas emissions to 108 per cent of 1990 levels by 2012, principally through reduced land clearing.

It is important to acknowledge the difference between emissions from horticulture and the rest of the primary industries.

Horticulture’s contribution to these emissions is small – approximately 1% of agriculture’s greenhouse gas emissions (GGEs), which equates to ~0.2% of total national emissions.

Emissions from horticulture production result mainly through nitrous oxide release from the use of nitrogenous fertilisers.

Source: Calculated from Agricultural Soils statistics 2009.

Horticulture further acknowledges that it has a part to play in mitigating the nation’s emissions. However, horticulture has a limited ability to mitigate compared to other primary industries – the industry is a small emitter and reduction of these emissions will mainly come from improvements to fertiliser management and application. Some growers are members of the Greenhouse Challenge Plus, a partnership with the Australian Government to improve energy efficiency and reduce GHG emissions. The emissions reductions from these improved practices will be much smaller than potential emissions gains in the livestock industry.

There is a need to ensure that industry members are aware of the complexity surrounding the area of mitigation. This includes clarifying terminology to dispel confusion, assessing the actual amounts of emissions produced through horticulture production (such as through carbon footprinting and/or life cycle analysis) and determine practices to reduce GGEs cost effectively where appropriate.

Two of the priorities for Australian Horticulture in mitigating greenhouse gasses are to determine the contribution (“Carbon Footprint”) which all horticulture (and specific regions and commodities) make to N2O and CO2 emissions, and to identify and promote horticulture-specific Best Management Practices (BMP) which minimize N2O and CO2 emissions, and at the same time promote the simultaneous goals of productivity, sustainability, adaptability and abatement.

Actions addressed by this priority are intended to answer the questions:

“Do we understand how to reduce greenhouse gas emissions from horticulture cropping systems?” and “Are current fertilizer management practices in horticulture appropriate for managing N2O emissions?”

The Horticulture Climate Change Action Plan will be implemented through the HAL Environment Portfolio, in consultation and on behalf of industry. To achieve this there is a need to focus on empowering industry leaders, facilitating meaningful partnerships, encouraging innovation and adoption of research, informing policy and positioning the industry.