About our Nitrogen addiction

Extensive fertilizer use causes high levels of Nitrogen compounds in air, soil and water. This has adverse effects on biodiversity, water quality and soil fertility. This is known as the Nitrogen crisis, and is a burning problem here in the Netherlands.

So why do we even need Nitrogen fertilizer?

In short, all humans and animals require Nitrogen to form our DNA and proteins. However, we can't extract Nitrogen directly from the air, since the bond between the two Nitrogen atoms is too strong, so we obtain it from plants and animals. But even plants cannot extract the Nitrogen from the air independently. The entire food chain thus relies on a small group of Nitrogen-fixing bacteria to facilitate this process. But the production rates of Ammonia are naturally limited by the population of those bacteria, which means that a land area can generate just so much biomass.

In nature, some plants prefer low Nitrogen conditions, while others thrive in high Nitrogen concentrations. Similarly, some soils can retain Nitrogen (and other nutrients) better than others.

Here in the Netherlands, we face an unfavorable combination of sandy soil and frequent rain, causing nutrients to wash away quickly. This leaves plants with limited time to access these nutrients, and most plant species in the Netherlands are adapted to low Nitrogen conditions.

A controversial Nobel prize

Historically, the Netherlands has always been an agrarian country, focusing on crop and livestock but in small scale. The post-WWII era marked a shift towards large-scale agriculture when food was in dire need. The strategy was - create food at scale - for the community and for the economy. This strategy paid off, and the Netherlands has become one of the top agricultural exporter worldwide.

For large-scale agriculture, the addition of Nitrogen is crucial and is the primary factor determining just how much protein can be generated. It first became readily available in the early 20th century when Fritz Haber, a German scientist found a way to produce Ammonia industrially, bypassing the rate-limitation of Nitrogen-fixing bacteria. For that achievement he was awarded the Nobel prize. A true tragic figure, he later went on to develop deadly Chlorine gas for his motherland in WWI, only to later be persecuted by the same for his Jewish origin, flee his homeland and watch his research lead to the murder of his own people in the gas chambers.

Nevertheless, the invention of industrialized Ammonia production led to the greatest boost in history for agriculture, and to this day, industrially generated Nitrogen remains the most prominent component in fertilizers.

An Addiction to the Medicine

Like with medicine, excess Nitrogen has side effects, one of them is the acidification of the soil. The increased acidity in the soil makes nutrients like calcium and magnesium less available to plants. Additionally, the heightened acidity creates less favorable conditions for various bacteria, leading to a decline in their populations, and eventually complete death of the soil.

When Nitrogen-fixing bacteria disappear, plants lose their natural Nitrogen source, becoming even more dependent on artificial Nitrogen injection. Now, they lack not only Nitrogen but also other essential nutrients that depend on biological relationships. This necessitates the artificial introduction of these nutrients as well, gradually reducing soil fertility and eventually causing financial loss.

There is a Better Way

Not all is lost. Fortunately, the Nitrogen problem is 'easy' to solve due to the very short natural Nitrogen cycle (compared to the millions of years that the Phosphors cycles take). In the future, our focus should shift from maximizing crop yield to maximizing soil health. This involves planting crops that are more adapted to the natural conditions in the region, planting Nitrogen-fixing plants (plants that host Nitrogen-fixing bacteria in their roots) and nurturing the soil as a whole, with special care to its hidden biology. This will lead to better sustainability, not only of the planet, but also of the soil as a business resource.

A crucial precondition for maintaining healthy soils is the systematic measurement of soil conditions and the development of new methods to evaluate soil health. This is our goal at Aardvark Sensing.

This is part of a series of short articles about the #nitrogencrisis (with focus on the Netherlands), the physics and biology behind it, measurement techniques, politics and solutions.

Read also How does excess Nitrogen adversely affect biodiversity