Speech by Professor Gerry Boyle, at the IIEA conference The Greening of Irish Ag
Introduction Minister, Ladies and Gentlemen, distinguished guests.
Minister, Ladies and Gentlemen, distinguished guests.
Teagasc, as Ireland’s agricultural and food development authority, has as one of its three central goals the aim to “Support Sustainable Farming and Improve the Environment”. Nearly 30% of our annual research resources or about €10.4 m. are devoted to research on the agri-environment. This is a multi-disciplinary programme and involves nearly 30 researchers and over 60 support staff. In addition through our network of agricultural advisory offices throughout Ireland we have a dedicated core of over 120 “Environment and Good Farm Practice” consultants, apart from an additional 160 consultants that work directly on theRural Environment Protection Scheme.
Thus Teagasc is by far the leading national research and development agency working on the agri-environment.
Therefore I very much welcome this event today organized by the Institute for International and European Affairs (IIEA). I also appreciate the opportunity given to me to outline some of Teagasc’s environmental R&D work that is specifically concerned with GHG emissions.
Agriculture accounted for 26.8% of total Irish greenhouse gas emissions in 2007 but this has been reducing over time from a figure of 35% of total emission in 1990. For example, agricultural emissions have decreased by 1.36m tonnes CO2 since 1990, or 6.8%. In an international context, Ireland’s profile of emissions is unusual in the developed world. New Zealand is the only developed country with a higher proportion of emissions from agriculture than Ireland, and the EU average is substantially below our level. This is due to the importance of agriculture in our economy.
Fig. 1: Emissions from agriculture in various countries worldwide.
Ireland is also unusual in the share of agricultural emissions coming from livestock. Over 50% of agricultural emissions is methane from enteric fermentation, and most of the remainder is nitrous oxide released from soils (Figure 2). This makes the problem of reducing our emissions more intractable, as we shall see later.
Fig. 2: Sources of agricultural emissions in Ireland.
Source: EPA 2006
Challenges in reducing agricultural emissions
- Food security will require an increase in food production.
- Reducing emissions in Ireland by reducing food production will cause ‘leakage’ of emissions to whatever country increases production.
- Gaining credits for afforestation and biomass production for bioenergy is problematic but there is no basis in logic for the agricultural sector not benefiting in accessing these offsets given that it is farmers that will need to alter their land use practices.
- There are economic, social and moral implications of reducing the livestock herd.
- New technical solutions require a sustained research effort.
Teagasc’s research programme on gaseous emissions
Efficiency and emissions reduction go hand in hand
It has become increasingly clear that reductions in green house gases can be brought about by more efficient production systems. Nitrogen lost to the atmosphere is also nitrogen lost to the farmer. In other words an emissions reduction strategy can lead to ‘win-win’ outcomes. There is a range of agronomic practices that can also result in a reduction of greenhouse gases e.g.:
- Changing the timing of slurry spreading and changing the methodology of spreading can lead to a greater capture of nitrogen by grass. This means less fertiliser use by farmers and also less gaseous emissions.
- Matching nitrogen usage to soil type which is a new area of research will lead to significantly lower nitrogen usage which in turn will lead to reduced emissions.
- A greater use of clover on farms will lead to less nitrogen used and therefore less emissions of greenhouse gases.
- Use of nitrate inhibitors will slow down the transformations of nitrogen in soils, which ultimately lead to less reductions in greenhouse gases.
- Extending the grazing season helps reduce costs on farms and reduces greenhouse gases
- Increasing growth rates of cattle to enable slaughtering at a younger age helps to reduce methane production.
Through the intensive promotion of these technologies it is expected that on dairy farms, for example, that it is feasible reduce the greenhouse emissions per litre of milk produced by somewhere between 20 and 50% over a relatively short time period.
Indeed significant progress has been made over the past number of years in reducing greenhouse emissions from agriculture. Technological advances in dairy production, for example, have led to a drop of 12.4% in the amount of methane produced per kg of milk between 1990 and 2006 (Figure 4), thereby demonstrating the relationship between greater efficiency and reduced emissions. Efficient rearing of cattle leads to earlier slaughter and lower lifetime greenhouse gas emissions. Over the period since 1990, the age of slaughter of beef cattle has been significantly reduced. In 1990, 44% of male cattle were over 30 months of age at time of slaughter, this has now reduced to 15% in 2006 resulting in significant reductions in greenhouse gas emissions.
Fig. 4: Amount of methane emitted per kg of milk produced (1990 = 100)
Methane is the main agricultural greenhouse gas produced in Ireland, mainly from enteric fermentation or digestion in the forestomach of ruminants such as cattle and sheep. It is a natural by-product of the digestion of feeds, particularly fibrous ones. Teagasc is looking at abatement strategies to reduce these emissions. These strategies include dietary modifications, additives or probiotics to reduce methane production, breed selection, increasing the length of the grazing season as grazed grass gives rise to less emissions than silage based diets, and improved pasture quality. The breeding of more efficient animals producing more product from a given amount of feed, and thus have less emissions per kg of milk or meat produced is very important. This requires a lot of basic science to understand the physiological and genetic factors controlling digestion and microbial processes, and emissions of methane from the rumen.
Reductions in the emissions of nitrous oxide
Nitrous oxide is produced from soils as part of the nitrogen cycle and is a significant source of green house gases. Progress is being made on reducing amounts of nitrous oxide emissions e.g. improved nutrient management has led to a 35% reduction in fertiliser use in the last 10 years, equivalent to a reduction of over 0.5 million tonnes of CO2.
Technology is being researched by Teagasc to further minimise nitrous oxide losses from soils. This research includes optimising the application of organic and inorganic sources of fertilisers to reduce nitrogen fertiliser usage and emissions. Other techniques being researched include the application of nitrification inhibitors and the more efficient use of clover as a nitrogen source.
If more carbon can be sequestered by Irish soils, this will help to offset other greenhouse gas emissions. Teagasc is examining the effects of differing agronomic practices (grass and tillage) on soil organic carbon stocks. In addition, there are projects examining the effects of land use change and tillage management on carbon sink activity.
In this context it is of course also important to remember that the most obvious means of allowing agriculture to better meet its GHG targets is to include forestry and renewable energy crops as an agricultural landuse.