Whole farm systems analysis of greenhouse gas emission abatement strategies for dairy farms

1. Whole farm systems analysis of greenhouse gas emission abatement strategies for dairy farms Richard Rawnsley, Karen Christie, and Rob Kildare

2. Climate Change Warming of the climate system is unequivocal Humans are very likely to be causing most of the warming that has been experienced since 1950 It is very likely that changes in the global climate system will continue well into the future, and that they will be larger than those seen in the recent past, (IPCC, 2007). • Increase in the atmospheric concentrations of greenhouse gases (GHG),is widely believed to be responsible for the observed increase in global mean temperatures through the 20th century, Source - BOM, 2008

3. water vapour • carbon dioxide • methane • nitrous oxide • ozone • CFCs Greenhouse gases On earth the most abundant GHG’s are Source, Technical summary; in Climate Change 2001: The Scientific Basis, (ed.) J.T. Houghton, Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. Dai, K. Maskell and C.A. Johnson

4. Greenhouse gases Australia’s net GHG emissions totalled 576 Mt CO2 –e, approximately 1.2% of world’s GHG emissions Source, Australian Greenhouse Office, (2006) • Agricultural responsible for • 84% of the nitrous oxide and • 59% of the emissions of methane Source, Australian Greenhouse Office, (2006)

5. Greenhouse gases Agriculture emissions come from: Enteric fermentation in livestock: Emissions associated with microbial fermentation during digestion of feed by ruminant (mostly cattle and sheep) and some non-ruminant domestic livestock Manure management: Emissions associated with the decomposition of animal wastes while held in manure management systems Rice cultivation: Methane emissions from anaerobic decay of plant and other organic material when rice fields are flooded Agricultural soils: Emissions associated with the application of fertilisers, crop residues and animal wastes to agricultural lands and the use of biological N fixing crops and pastures Prescribed burning of savannas: Emissions associated with the burning of tropical savanna and temperate grasslands for pasture management, fuel reduction, and prevention of wildfires Field burning of agricultural residues: emissions from field burning of cereal and other crop stubble, and the emissions from burning sugar cane prior to harvest.

6. Dairy GHG Abatement Project Agriculture and in particular dairy presents a new set of challenges for emissions benchmarking that is not reflected in other sectors. • Project objectives • Identify methods of validating GHG emissions and abatement • Quantify the GHG emissions (including embedded emissions in key inputs) from three typical dairy farming systems • Quantify the impacts of a range of GHG abatement strategies • Develop a abatement calculator for dairy farm systems

7. GHG emissions Enteric Methane Nitrous oxide Herd based strategies 10-20% potential Herd based strategies 10-50% potential reduction in urinary nitrogen Extended lactations Condensed tannins Reduced herd size Nitrification inhibitors in urine Higher FCE Higher FCE Extended longevity in the herd Balance crude protein in the diet Feed based strategies 10-20% potential Soil based strategies 10-20% potential Nitrification inhibitors Feeding fats & oils Stand-off pads during winter Feeding condensed tannins Improved drainage Feeding ionophores Improved irrigation management Maximise diet digestibility Fertiliser management- rate/ timing/ formulation Abatement Strategies Research undertaken in Australia and New Zealand has identified an array of potential abatement strategies for dairy farm systems.

8. GHG emission sources from dairy On farm N2O On farm CH4 On farm CO2 Pre-farm

9. Intensity of GHG emissions The intensity of GHG’s is the amount of GHG’s produced per unit of product • The intensity of GHG’s can be reduced in two ways: • Increasing output per unit of emissions, or • Lowering emissions per unit of output

10. The intensity of GHG’s is the amount of GHG’s produced per unit of product • The intensity of GHG’s can be reduced in two ways: • Increasing output per unit of emissions, or • Lowering emissions per unit of output Intensity of GHG emissions

11. Intensity of GHG emissions The intensity of GHG’s is the amount of GHG’s produced per unit of product • The intensity of GHG’s can be reduced in two ways: • Increasing output per unit of emissions, or • Lowering emissions per unit of output

12. Intensity of GHG emissions The intensity of GHG’s is the amount of GHG’s produced per unit of product • The intensity of GHG’s can be reduced in two ways: • Increasing output per unit of emissions, or • Lowering emissions per unit of output

16. The way forward • Profitability versus emission reduction. Need to focus on win-win abatement strategies • Emissions reporting – how ? • Formulate emission factors that are more location specific • Maintain a research focus where maximum results can be achieved • A CPRS should not diminish our international competitive advantage • Develop approaches to the emerging conflict between adaptation to CC and GHG abatement (eg. extensification vs intensification)