RIVM plays an important role in mapping the amount of nitrogen in the air, soil and water. On these web pages, we look at how much nitrogen ends up in nature through the air. You can read more about nitrogen in water and soil on the website of the Landelijk Meetnet effecten Mestbeleid (Dutch only). 

What is nitrogen? 

Nitrogen (N2) is a colourless and odourless gas that is all around us. On its own, nitrogen is not harmful to people and the environment. However, what we often mean when discussing nitrogen are the chemical compounds of nitrogen in the air that can be harmful to people and the environment: nitrogen oxides and ammonia. 

• Nitrogen oxides (NOx, compounds of nitrogen and oxygen) mainly end up in the air as a result of emissions from traffic and industry. NOx is the sum of nitrogen monoxide (NO) and nitrogen dioxide (NO2). 
• Ammonia (NH3, a compound of nitrogen and hydrogen) primarily comes from livestock animals. Manure from animals evaporates as ammonia and so ends up in the air. It is produced in stables and during the fertilisation (also with artificial fertiliser) of pastures and farmland. A small amount of ammonia is produced by other sources, such as industry, construction and traffic. 

The nitrogen problem 

The Netherlands has been emitting a considerable amount of nitrogen for years, much of which ends up on the soil surface and in nature. In many nature reserves in the Netherlands, so much nitrogen is deposited that it can be damaging to vulnerable nature. This, in turn, is harmful to biodiversity, the quality of surface and groundwater and human health. EU European Union (European Union ) legislation and regulations require Member States to protect vulnerable nature. In 2019, the Council of State assessed the European regulations and ruled that nature must be better protected. This is why there are strict rules for nitrogen emissions. 
In relative terms, the Netherlands is a main emitter of nitrogen in Europe, with its neighbouring countries not far behind. 

RIVM registers, measures and calculates using models 

The debate surrounding nitrogen is characterised by many scientific terms. The following three important terms mean different things about the amount of nitrogen: 

• Nitrogen emission: the way in which nitrogen is emitted into the air and the sources of this nitrogen. 
• Nitrogen concentration: the amount of nitrogen in the air. 
• Nitrogen deposition: the amount of nitrogen that deposits onto the plants and the soil surface.

RIVM and various partner institutes register nitrogen emissions into the air. We measure the concentration of nitrogen oxides and ammonia in the air in many different parts of the country through a monitoring network. We also measure nitrogen depositions. However, we cannot measure everywhere, which is why we use models to gain an accurate impression of nitrogen depositions from the national level down to the local level. Using these calculations and models, we can also make projections for the future. 

Monitoring, advice and research 

The data that RIVM collects offers insight into nitrogen depositions and into the vulnerable nature where nitrogen is being deposited. Government policy has established by how much nitrogen depositions in vulnerable nature have to be reduced. RIVM tracks to what extent this target is achieved and if the goals of the policy will also be achieved in the future. RIVM issues advice to policymakers on the development and adjustment of nitrogen policy on the basis of scientific knowledge. The government uses this as input for policymaking. RIVM also conducts additional scientific research and advises local and regional governments on measurements and calculations. This advice and research are laid out in reports and scientific publications on this website or in scientific journals. 

Open data 

We make as much of our data publicly available as possible and publish it online. Sometimes, however, we deal with privacy-sensitive data that cannot be shared. You can view all the open data about nitrogen in the air. 
You can also access all open data in RIVM’s possession at data.rivm.nl.  Lastly, you can find plenty of nitrogen data with interpretation on Environmental Data Compendium. 

Cooperation 

National and international cooperation strengthens the quality of our work. We share and develop knowledge within various partnerships.