Mitigation of non CO2 Greenhouse Gas Emissions from Agriculture

1. Mitigation of non CO2 Greenhouse Gas Emissions from Agriculture Presentation to the in-session workshop of the Ad-hoc Working Group New Zealand Delegation to COP/MOP12

2. Agriculture greenhouse gas emissions • Represents ~14% of global GHG emissions • Represents ~7.4% of Annex 1 emissions • Represents ~26% of non-Annex 1 emissions • Mitigation options are relatively limited

3. Agriculture is important • Agriculture supplies food to the world – population expected to increase from 6 billion to 9 billion by 2050 • Agriculture is important for the sustainable development of communities and national economies, for both developed and developing countries

4. Industrial processes 5.6% (mainly CO2) Solvents 0.1% fertiliser 3% Energy – otherprocesses 15.1% (CO2) urine 15% methane 31% Transport 19.2% (CO2) air travel 1.3% Agriculture 49.4% (methane and nitrous oxide) Electricity 8.1% (CO2) Waste 2.5% (mainly methane) New Zealand emissions

5. NZ agriculture situation • A reliance on the export of primary products • Dynamic land use – meeting market demand • 49% of total GHG emissions from agriculture (highest of any developed country) • Highly efficient production

6. NZ’s agriculture emissions profile

7. The challenge • Biological systems are complex • 64% of New Zealand’s agricultural emissions have no current feasible mitigation solution • At present, practical mitigation options for grazing ruminants and grazed pastures are limited • More research is required globally, however, this is of a lower priority in most developed countries

8. Current focus in agriculture • PGGRC – a government/sector partnership for agriculture research • Measurement crucial • Technology adoption becoming more of a focus

9. Mitigation of ruminant methane emissions • Animal variability • Genetics (variation between animals – 14-26 g-CH4/kg dm intake) • Nutrition • Production system • Microbial • Direct modification of microbial processes: Protozoa, Acetogens, Phage, Methanogens • Vaccination • Monensin (up to 10%) - in grain diets – forage diets 0% • Medium chain fats • Plants • Plant extracts • Plant species (tannins up to 10%) • High sugar grasses

10. Mitigation of nitrous oxide emissions • Reduce the amount of excreta N • Replace N boosted grass with maize silage • High sugar grasses • Shift N balance from urine to dung • Increase N efficiency of excreta and N fertiliser • Restricted grazing of dairy and beef animals • Effluent utilisation on dairy farms • Nitrogen fertiliser timing, rates and forms • Nitrification inhibitors – DCD has real promise and is commercially available in NZ • Avoid anaerobic soil conditions • Improve drainage • Avoid compaction

11. Conclusions • There is no simple single solution for CH4 and N2Ofrom agriculture - a package of measures will be required • Reducing methane emissions from grazing ruminants currently has limited options available • Options need to be evaluated at the farm scale and for all three major GHGs collectively – GHG footprint of total system • GHG measurement will continue to be an issue • Increased international effort – particularly in ruminant methane mitigation in pastoral agriculture is needed