Too much nitrogen in the environment – what steps are we taking?

Nitrogen is essential for life on Earth – for instance, for plant growth. However, excessive inputs of reactive nitrogen, which forms compounds with other substances, are harmful to humans, animals and plants. Nitrogen dioxide, ammonia and particulate matter lead to a deterioration in air quality. Nitrate contaminates groundwater. Inputs into the soil lead to a decline in biodiversity and the eutrophication and acidification of ecosystems. Nitrous oxide causes considerable changes to the climate. Avoiding and limiting these impacts also comes at a high economic cost.

At present, around 1.5 million tonnes of reactive nitrogen are released each year in Germany. Agriculture is responsible for the largest share of nitrogen emissions at 67 percent, followed by industry and the energy sector at 16 percent and the transport sector at 11 percent. To reduce nitrogen emissions into the water, air and soil, changes are needed in key areas of the economy and daily life, including agriculture, energy supply, mobility and consumption habits.

In Germany, a lot has already been done to reduce nitrogen emissions through measures in the areas of air pollution control and water and soil protection. This has reduced total emissions by around 40 percent since 1995. Overall, however, these measures have not yet led to the limit values and environmental quality objectives applicable in Europe being reliably met. The German government wants to take all measures necessary to fully meet European legal obligations to reduce nitrogen pollution in water and air and consequently avoid paying fines to the EU. Reactive nitrogen in the form of ammonia will also play a role in the energy transition in future. Suitable renewable energy sources are needed to achieve the goal of climate neutrality and hydrogen will play a key role here. Ammonia, a storage medium for hydrogen, will likely be used to transport hydrogen by ship. Here, too, the Environment Ministry is responsible for ensuring that transport and the necessary infrastructure are as environmentally friendly and safe as possible. Further information can be found on the web pages of the German Environment Agency.

National total emissions target for nitrogen

The Federal Environment Ministry, or BMUV, is currently drawing up a proposal for a national target for total nitrogen emissions and proposals for measures to achieve this target. From an environmental perspective, the aim is protect all ecosystems in Germany from high nitrogen inputs to such an extent that they are not adversely affected and enjoy good environmental status. The total emissions target to be set by policymakers will be based on environmental requirements.

Due to the often complex and gradual effects of nitrogen, it is not possible to convey its negative impacts fully or immediately. As a result, the problems related to nitrogen do not receive adequate attention despite the urgency and far-reaching consequences. The BMUV is working to ensure that the public is better informed about the consequences of high nitrogen emissions, thereby creating greater awareness of the problem. The aim is to empower individuals to change their own behaviour.

The reactive nitrogen environment atlas (Umweltatlas "Reaktiver Stickstoff") published by the German Environment Agency (UBA) also raises awareness and provides information about nitrogen. The clear and informative web page sheds light on the environmental problem and its various facets.

To effectively reduce nitrogen emissions, the BMUV is pursuing a national nitrogen reduction strategy. The systemic policy approach joins the forces of all stakeholders and helps to identify and solve the environmental problem as a whole. This also means that all relevant emissions-producing sectors have to do their part to reduce nitrogen levels. The first Nitrogen Report was adopted on 31 May 2017 to raise awareness of this issue and clarify the German government’s position. It was drawn up at the initiative and under the lead responsibility of the BMUV.

The German government’s first Nitrogen Report makes clear: "[...] worldwide trends in population growth, increasing consumption levels, high-resource diets, the increase in private travel and growing energy requirements due to increasing mechanisation and industrialisation [...] lead to growth in nitrogen emissions. [...] Despite all efforts and considerable mitigation successes, emissions continue to be far higher than health and environmental targets at UN, EU and national level. [...] The German government’s overall goal is to reduce nitrogen emissions to levels that are compatible with the environment and human health. In order to achieve this, the government is using an integrated reduction approach that is geared to targets and requirements agreed at EU and international level."

To support the work on the nitrogen strategy and potential reduction measures, a citizens’ dialogue on the problems associated with nitrogen was carried out in autumn 2019 with the involvement of 110 citizens across four cities. The outcome of the dialogue was 16 proposals for nitrogen reduction measures, which were compiled in a citizens’ advisory document entitled "Nitrogen: too much of a good thing" (Stickstoff: Zu viel des Guten!). On 12 February 2020, 23 participants presented the document to the Federal Environment Minister.

The global dimension of the nitrogen problem was the focus of the world’s largest conference on nitrogen, the 8th Global Nitrogen Conference of the International Nitrogen Initiative (INI), which was held in Berlin from 30 May to 3 June 2021. As a renowned network of scientists, the INI organises a conference every three years centred on the latest research findings, policy strategies and measures to reduce nitrogen. The INI Conference was entitled “Nitrogen and the United Nations Sustainable Development Goals” (SDGs) because the achievement of at least 9 of the 17 SDGs is also dependent on the sustainable use of nitrogen and effective nitrogen management. Participants from 60 countries attended the international conference. The 2021 INI Conference was organised with the support of the German Environment Agency (UBA) and the BMUV. The final document of the Conference, the Berlin Declaration, summarises the science policy conclusions reached at the Conference.

An integrated approach to the problem, which takes into account the entire nitrogen cycle, also reflects the position of the United Nations Environment Programme (UNEP). At the fourth UN Environment Assembly (UNEA) of UNEP in March 2019, a resolution on sustainable nitrogen management was adopted for the first time, underscoring the need for global action. Building on this, another resolution with the same title was adopted at the fifth UN Environment Assembly in March 2022. Progress made on both resolutions was reported on at UNEA 6 in February 2024. An international UNEP Working Group on Nitrogen is coordinating implementation of the resolutions and the next steps. The Member States are participating in this process as National Focal Points.

The various strategies of the European Commission’s European Green Deal (for example the Zero Pollution Action Plan, the Farm to Fork Strategy and the Biodiversity Strategy) contain ambitious nitrogen reduction targets. According to the Farm to Fork Strategy, the European Commission will "act to reduce nutrient losses by at least 50 percent, while ensuring that there is no deterioration in soil fertility. This will reduce the use of fertilisers by at least 20 percent by 2030."