Tackling the nitrogen challenge

Researchers from the program led an international team to develop the National Nitrogen Budgets Guidance Document—specific guidance for European countries on how to use their available data for nitrogen budgets.

The approach could form the foundation of an International Nitrogen Management System, applied to countries around the world. At the same time, researchers are also working to extend the concept to individual farms, to give local, small-scale coverage.

The researchers used a framework made up of stocks and flows, which accounts for all nitrogen as it moves though the entire system. This approach minimizes the chances of unforeseen trade-offs; a solution drawing nitrogen out of the air, for example, is no good if it ends up polluting the rivers.

Using the generic rules of the guidance document and nitrogen data specific to their country, national experts can create accurate nitrogen budgets and assess flows. Comparing flow estimates allows users to validate information, and supplement missing data. For instance, if you know how much nitrogen fertilizer went on to the field and how much stayed in the soil and was taken up by plants, then you can deduce how much was lost to the rivers.

The approach allows countries to compare performances and share best practices, and forms the backbone of intervention planning to reduce nitrogen pollution across the system.

IIASA researchers have used the approach to examine nitrogen flows in non-food industrial products (polymers, wood and paper products, waste), and nitrogen related to pets, gardens, and energy use [1]. The team has also used the framework to assess the costs of measures aimed at reducing nitrogen emissions from livestock production via new feeding strategies [2].

The guidance document is fully compatible with existing reporting guidelines, specifically regarding countries’ obligations to the UN Framework Convention on Climate Change, the UN Economic Commission for Europe (UNECE), and Eurostat. It has also been adopted by the UNECE Convention on Long Range Transboundary Air Pollution, and was specifically referred to in a 2016 EU Directive on atmospheric pollutants.

The approach could form the foundation of an International Nitrogen Management System, applied to countries around the world. At the same time, researchers are also working to extend the concept to individual farms, to give local, small-scale coverage.