By: Teagan Smith
We take for granted the growth and availability of our food, but behind that now well-oiled machine of bounty was the invention of fertilizer by Fritz Haber and Carl Bosch. “Today, nearly 80% of the nitrogen found in human tissues originated from the Haber-Bosch process” (Nature). On top of that, they are estimated to have allowed for, if not saved, the lives of over a billion people from premature death due to starvation (Our World in Data).
What this means for us as humans is that we have become accustomed to and reliant on this artificial production of nitrogen to sustain our agriculture system. As we continue to strip our soils of what was once naturally fixed nitrogen with mono-crop after mono-crop that uses the same exact nutrient to grow, we simultaneously continue to increase our reliance on fertilizer. In this way, we are creating a permanent relationship between chemical and nature. Without the natural nitrogen in the soil, there had to be a perfect science developed to understand just how much nitrogen should be applied to the earth. There is a distinct amount of nitrogen that each crop is able to uptake; too little nitrogen and significant yield is lost, too much nitrogen, and leaching and runoff occur. To a farmer, the choice of how much to apply is an easy one: too little means a crucial loss of income for an already struggling business, too much has little to no punishment or regulation. One can guess which way the traditional farmer leans. “Globally farmers apply around 115 million tonnes of nitrogen to our crops every year. Only around 35% of this is used by them, meaning 75 million tonnes of nitrogen runs off into our rivers, lakes, and natural environments” (Our World in Data).
Now onto all that excess nitrogen. What becomes of it as it runs into these rivers, lakes, and natural environments? Well, if you have ever been to the Gulf of Mexico or the Chesapeake Bay in the summer and smelled a distinctly fishy scent, there’s your answer. It’s not fried-up fresh fish, it’s millions of dead ones floating to the surface to rot. These fish kills occur because too much nitrogen in the water causes algae to grow faster than an ecosystem can handle. These algal blooms then die and are eaten by bacteria which utilize oxygen to decompose organic matter. They are eating so much algae so rapidly in these areas that they entirely remove oxygen from the water. This leads to fish and other organisms suffocating and dying. On top of these fish kills, some algal blooms can harm humans and animals due to the toxins they produce. In drinking water, excess nitrates can be harmful and even deadly to infants. In our atmosphere, nitrogen can cause acid rain, smog, and ozone, polluting, altering, and killing whole ecosystems.
Nutrient pollution is one of the only pollutants that is in all 50 states in the U.S. but receives little to no attention because of how integral it is to our food system. Simply put, there needs to be a much greater focus on educating farmers and the everyday consumer on the impacts that excess nutrients can have on the environment and on the human body. Fortunately, there are solutions that have already been shown to be successful in reducing nitrogen pollution from agriculture: year-round groundcover to prevent runoff, planting field buffers to clean water before it reaches larger sources, and managing livestock access to streams to prevent their waste from contaminating the water (EPA). It’s of course necessary for us to continue to use nitrogen in our farming, we’ve come too far with it to leave it behind. It has allowed us to grow food and grow as a human race like nothing ever has before. However, at the same time, it’s important to facilitate these sustainable practices and educate ourselves in order to reduce our anthropogenic impact on the nitrogen cycle and our environment as much as possible.