UBA’s forecasts show that the rigorous enforcement of existing legislation, some of which has just been updated – the national air quality control programme or the new requirements of fertiliser law, for example – is expected to reduce nitrogen emissions sufficiently in respect of the proposed cap. The federal government's climate package will also contribute to nitrogen reduction. However, implementation of the current legislation, also at the regional and local level, must be reviewed at regular intervals as long as the limits have not yet been reached in all sectors. The multisectoral cap dovetails current environmental targets for air, groundwater, ecosystems and health and regional requirements across Germany and shows the contribution of the individual sectors towards the overall target. The cap is designed for rapid implementation and as a milestone target, which is why the overall target focuses on current policy targets rather than achievement of good environmental status for all areas. In the long term, further reductions will also be necessary to achieve good environmental status for all nitrogen-polluted areas in Germany. The instrument nevertheless sends an important signal of cooperation and action by society as a whole across various political and societal sectors.
For years, Germany has fallen short of its environmental quality targets for forests, surface and coastal waters, groundwater and air due to excessive nitrogen pollution. This can also have an impact on human health. The majority of nitrogen emissions come from animal husbandry, fertiliser application and fuel combustion processes in transport. However, energy use, households and the production of consumer goods are also contributing factors. Nitrogen, which is contained in various chemical compounds, is an indispensable building block of all life. As atmospheric nitrogen N2, for example, it makes up 78 per cent of the air we breathe. It is harmless in this form but most living organisms are unable to use it. In combination with other elements, the quick-change artist nitrogen causes problems for humans and the environment because, as a rule, it is the dose that makes the poison. Excessive amounts of nitrogen dioxide (NO2), ammonia (NH3), nitrate (NO3-) and nitrous oxide (N₂O), for example, lead to potentially harmful air and groundwater pollution, eutrophication of oceans and seas, and a loss of biodiversity.
With its proposal for a national cap, UBA is also appearing in its host role at the 8th International Nitrogen Conference. The conference is the world's largest of its kind and is at the interface between science and policymaking. Over 500 participants from all continents are expected to attend the 4-day virtual conference starting 31 May.