The nitrogen problem keeps the Netherlands firmly in its grip. Residential construction is delayed at a maximum speed of 100 kilometres per hour on the highway, and farmers are threatened with closure. Where does that nitrogen come from, and where does it cause the biggest problems? And how is the Netherlands doing compared to other countries?
What is the history of the nitrogen problem?
‘Nitrogen crisis’ is a somewhat confusing term. After all, nitrogen is all around us, in the form of air. This form of nitrogen has no effect on nature.
There are also harmful forms of nitrogen compounds, for people and nature. These are mainly produced by humans: ammonia and nitrogen oxides. Ammonia is a chemical compound between nitrogen and hydrogen, which is mainly released in livestock farming. Nitrogen oxides, a compound between nitrogen and oxygen, are mainly released when burning fuel in industry and traffic.
The problems with nitrogen are not something of recent years. In the fifties and sixties of the last century, the emission (’emission’) of ammonia and nitrogen oxides grew rapidly, and with it their precipitation (‘deposition’) in nature. Livestock farming became more intensive, and fertilizers were used more and more, so that food production and the export of agricultural products grew strongly. Industry and traffic also grew rapidly after the Second World War.
Nitrogen emissions have fallen sharply since 1990. For example, emissions of nitrogen oxides have decreased by almost three-quarters in the past thirty years. This is due to measures in factories, the energy sector and traffic, such as the introduction of the catalytic converter.
Ammonia emissions also fell. In 1991 stricter rules for manure were introduced to reduce emissions. But between 2013 and 2017, the livestock increased sharply due to the abolition of the milk quota. And more livestock means more ammonia, which stalled the decline.
Where does most nitrogen come from?
Two-thirds of nitrogen deposition is caused in the Netherlands itself, according to RIVM estimates: mainly through agriculture, traffic and industry. Of these sectors, agriculture contributes by far the most to the amount of nitrogen in nature.
The remaining third is nitrogen from abroad. It is important to bear in mind that the Netherlands exports four times as much nitrogen by air as it imports, but more on that later.
Of these categories, ‘marine ammonia’ will disappear from the overviews this autumn because the ammonia found in coastal areas probably has little to do with the sea. From then on, that category will be called ‘ measurement correction ‘.
Incidentally, measuring nitrogen is difficult and expensive. It costs several hundred thousand euros for one farm. Therefore, nitrogen measurements for common houses are used in models to calculate which places emit the most nitrogen.
That data is then used in another model, which calculates how much nitrogen ends up in nature and where that nitrogen comes from. These calculations are checked with approximately three hundred measurements for ammonia and more than seventy measurements for nitrogen oxides. Many of the charts and maps on this page include data from those models.
Who emits the most nitrogen?
So where are the largest emitters of nitrogen oxides and ammonia? Minister Christianne van der Wal (VVD, Nature and Nitrogen) recently published the top 100 list of companies. That did not go completely smoothly, but the correct list is now public.
The data of companies that emit a lot of nitrogen oxides can be found via a special website. By far the largest emitter is Tata Steel in IJmuiden, followed by Schiphol and Dow Benelux in Hoek. The map shows the ten largest companies.
When it comes to ammonia, the list is less easy to find. Ninety livestock farms are in the top 100 emitters. Due to privacy laws, the names and locations of those companies are not made public. It is known that much of the emissions come from North Brabant and Limburg.
Incidentally, the three largest emitters of ammonia are industrial companies. It concerns Rockwool in Roermond , YARA in Terneuzen and Chemelot in Sittard-Geleen.
Are Netherlands emissions high compared to other countries?
Within Europe, calculated per hectare, the Netherlands is one of the leaders in nitrogen emissions. On average, European countries emit 11.2 kilograms of nitrogen per hectare. The Dutch value, 46 kilos, is more than four times higher.
Although nitrogen ‘blows into’ the Netherlands, the effect is much greater the other way around. Most nitrogen emitted in our country ends up on foreign soil. In net terms, the Netherlands is therefore an exporter of nitrogen.
And is the Dutch livestock really that big, compared to other countries?
Yes. A large number of pigs per hectare of agricultural land is particularly striking. Our country also has a relatively large number of cattle.
According to the latest data (from 2020), the Netherlands is the largest meat exporter in Europe; the much larger Spain is in second place. Exports account for about 60 percent of the income from the sale of meat.
Incidentally, the latest European figures on livestock are from 2016. The European statistical office Eurostat carried out a new census of the number of animals in 2020. Those numbers are expected this fall.
For which Dutch areas does this affect?
Part of all that emitted nitrogen ends up in nature, which leads to depletion and other problems. First and foremost: not all nature reserves are equally affected by nitrogen. This mainly depends on the type of soil and the groundwater level in those areas.
The government is obliged to protect nature reserves, which is why the nitrogen problem is so topical. The Netherlands has 161 Natura 2000 areas. These are nature reserves that the Dutch government believes should be protected. The compulsory protection of these areas is based on European rules.
Although nitrogen emissions and deposition have fallen sharply in recent decades, nature reserves still suffer from it. Nitrogen that settles in a nature reserve does not just disappear and ‘piles up’ for years.
Bargerveen, the Peel and the Brabantse Wal are examples of nature reserves where the pressure of nitrogen is very high. The influence of intensive livestock farming in the Gelderse Vallei, west of the nature reserve, is clearly visible on the Veluwe.
But sometimes the problems in nature reserves cannot be solved with Dutch measures alone. For example, three-quarters of the nitrogen in the Bargerveen nature reserve comes from abroad, especially from Germany.