Ammonia emissions into the air is a major threat to human health, causing cardiovascular and respiratory diseases. Atmospheric ammonia is also a significant source of acidification and excess nutrient loading, causing loss of biodiversity in many of the most vulnerable ecosystems. This calls for stronger action to reduce emissions.
Ammonia or NH3 mainly comes from manure produced by livestock and from mineral nitrogen fertilizers. In 2012, the agricultural sector accounted for 88.4 per cent of the total ammonia emissions in the UNECE region (excluding Canada and the United States). It is therefore a major contributor to air pollution. The issue is not a new one — a 30 per cent decrease in ammonia emissions has already been achieved since 1990 — but more needs to be done.
On 11 December, Parties to the UNECE Convention on Long-Range Transboundary Air Pollution adopted a new “Ammonia Framework Code” to help countries reduce ammonia emissions from agriculture.
The UNECE Executive Secretary Christian Friis Bach hopes that this will provide new impetus for emission reduction measures in the agricultural sector, and create a wider understanding of the benefits of reducing ammonia and nitrogen for human health and the environment. “Air Pollution is the number one health problem in our region and in the world today”, he noted, “All countries and all economic sectors must take their responsibilities to ensure better air quality.”
The new framework code, a revision of a first version adopted in 2001 under the Protocol to Abate Acidification, Eutrophication and Ground-level Ozone (Gothenburg Protocol), provides guidance for countries to establish their own national codes. It includes good practices on:
- Nitrogen management, taking account of the whole nitrogen cycle
- Livestock feeding strategies and measures to reduce emissions from animal excretions
- Low-emission techniques to store and to spread manure on fields
- Low-emission animal housing systems
- Measures to limit emissions from the use of mineral fertilizers.
For more information, please visit: http://www.unece.org/env/lrtap/welcome.html.
Notes to editors
The Convention on Long-range Transboundary Air Pollution was created in 1979. Over the years, it has been extended by eight protocols that identify specific measures to be taken by Parties to cut their emissions of air pollutants. The Convention has 51 Parties.
The 1999 Gothenburg Protocol to Abate Acidification, Eutrophication and Ground-level Ozone entered into force in 2005. It counts 26 Parties. The Protocol sets emission ceilings for pollutants such as sulphur and nitrogen oxides, non-methane volatile organic compounds and ammonia. The Protocol also sets tight limit values for specific emission sources (e.g., combustion plants, electricity production and vehicles) and requires best available techniques to be used to keep emissions down.
Nitrogen
The use of nitrogen fertilizers has led to a doubling of the flow of nitrogen compounds around the world in the past 100 years. Nitrogen (N) is important for plant growth and sufficient amounts are needed for plants to achieve optimum crop yields. However, about 80 per cent of nitrogen is lost from agriculture through leaching and run-off of nitrate or organic nitrogen and gaseous emissions to air.
The nitrogen that is lost to the environment has severe impacts on soils, air and freshwaters as well as on human health. While the world’s carbon cycle has received a lot of attention through climate change, public awareness about the world’s nitrogen cycle and the impacts of its imbalance is low. It has been suggested that the world’s planetary boundaries for interference with the nitrogen cycle have already been surpassed.
In many parts of the UNECE region, over-fertilization and deposition of too much atmospheric nitrogen acidify natural and agricultural soils, leading to a loss of arable land. Excess nitrogen loads also affect water quality and can lead to aquifers contaminated with nitrate and impure drinking water. Finally, interactions with nitrogen and its transformations also have an impact on the greenhouse gas balance with consequences for climate change.
Map showing estimated net anthropogenic nitrogen inputs according to the world’s main river catchments. Source: Sutton M.A. et al., (2013), Our Nutrient World: The challenge to produce more food and energy with less pollution. Global Overview of Nutrient Management. Centre for Ecology and Hydrology, Edinburgh on behalf of the Global Partnership on Nutrient Management and the International Nitrogen Initiative.