Fertilizers are natural or artificial substances that increase the productivity and growth of plants. When talking about artificial or chemical fertilizers the most-used ones are nitrogen fertilizers, which are nitrate based. They are one of the most effective chemical fertilizers, however in today’s age they are used excessively, which is detrimental to the environment.
Fertilizers are made up of compounds and chemicals including methane, carbon dioxide, ammonium, and nitrogen, and when such fertilizers are used too often, toxic greenhouse gases are emitted into the environment. Therefore, when fertilizers are used too often, the plants can’t use them all, and the excess fertilizer seeps into the ground water, which we ingest in the worst-case scenario. This can be very dangerous, if not toxic. Nitrogen fertilizer, for example, is dependent on nitrate, which is converted to nitrite, which is carcinogenic, when we drink water laced with traces of nitrate.
Another issue is that long-term overuse of nitrogen fertilizers containing ammonium can cause soils to become acidic. Furthermore, overfertilization induces excess salts in the soil, which reduces the crops’ ability to absorb water, resulting in weakened roots, draught tension, and ultimately crop death. Overfertilization, especially in nurseries, may result in seedlings of low quality and reduced capacity for growth and survival when outplanted.
What is being done against this?
Germany has implemented a nitrogen cap, which limits the amount of fertilizer that can be used in a given field. It also allows farmers to keep track of how much fertilizer they use, but the total limit is still much too low to avoid overfertilization.
What else could be done?
To actively prevent fertilizer from seeping into ground water, the nitrogen capping should be increased. Furthermore, instead of chemical anorganic fertilizers, organic fertilizers such as animal manure could be used, which is convenient because it already exists in vast amounts.