Cutting fertilizer use will not be enough to meet EU nitrogen targets

A study by the UFZ in Leipzig reveals that a 20% reduction in the use of nitrogen fertilizers will result in a relatively modest decrease in nutrient losses to soil. Regional agricultural systems are a decisive factor

by Matteo Cavallito

The 20% cut in chemical fertilizer use recommended by the European Union would not be enough to achieve the Green Deal’s goal of halving nutrient losses by 2030. This is claimed in a study by the Helmholtz Centre for Environmental Research (UFZ) in Leipzig published in the journal Nature Food. According to the authors, the loss of nitrogen—which is an essential element for the soil, but whose excessive diffusion causes environmental damage—is still too high in Europe, despite the decrease recorded in the 21st century following stricter regulations.

The impact of fertilizers varies from region to region

To better understand the current scenario, German researchers analyzed the annual nitrogen surplus in Europe between 1850 and 2019. In this way they showed how the impact of regulation varies greatly depending on the characteristics of the local agricultural system. This is an aspect that previous studies do not seem to have adequately considered. “Previous studies have assessed the feasibility of these targets by estimating N balances and potential N loss reductions under future scenarios,” the research states. “While insightful, they often focus on the aggregated EU level and do not fully account for regional variability.”

The fact, the authors explained, is that elements such as technology, land use, and different management practices prove to be crucial aspects.

For this reason, the authors argue, reducing fertilizers can have a significant positive impact “in countries like Germany, France and Poland, where it is heavily relied upon for agricultural production.” In contrast, “areas with high livestock density, such as Wales and the Netherlands, may benefit more from reducing manure use.” How, then, can the effectiveness of the EU strategy be assessed considering these variables?

Four categories

To answer this question, the study first suggested adopting a new classification. European countries were then divided into four categories:

• “Manure,” typical of countries with high livestock density such as the Netherlands and Denmark;
• “Synthetic fertilizers,” which includes those in Central Europe such as Germany and France, where more mineral fertilizer is used than animal manure;
• “Moderate use of manure and synthetic fertilizers,” typical of many Eastern European and Mediterranean countries;
• “Natural landscapes,” a category that includes Northern European countries such as Norway, Sweden, and Finland, where fewer inputs—mineral or animal—are used than the continental average.

The researchers then developed future scenarios for the four regional categories based on nitrogen surpluses for the period 2015-2019. While considering the reduction targets suggested by the FAO, and those set by the Green Deal.

Nitrogen in soils will be reduced by a maximum of 16%

According to researchers, if all Member States cut their use of mineral fertilizers by 20%, the excess nitrogen in soils would be reduced by between 10 and 16%. In other words, in the best-case scenario, the result achieved would be less than a third of the target (50% less dispersion than current levels calculated on average values for the period 2015-19).

All things considered, explains Andreas Musolff, hydrogeologist at the UFZ and co-author of the research, only “five countries – Sweden, Denmark, Latvia, Lithuania, and the Czech Republic – would halve their nitrogen surplus in this scenario.”

Finally, the study argues that the EU target could not be achieved even by implementing the most ambitious effort suggested by the FAO, which envisages a 43% reduction in synthetic fertilizers and a 4% reduction in animal manure, combined with modern technologies and management measures. Achieving that goal, the study concludes, would reduce the nitrogen surplus by 30-45%. In view of these scenarios, it is therefore necessary to take into account the many variables at play in order to develop appropriate strategies and achieve environmental targets.