The N2 Dilemma: Is America Fertilizing Disaster?
Where does our food come from?
These days, most people might think corn, the ubiquitous grain that provides the bulk of feed for our livestock; most of the sweetener for our soft drinks and snacks; and a large amount of our cooking fat.
But where does the corn — and other staple crops — come from? The answer to that question lies beneath our feet. Healthy soil is our food system’s bottom line. Without it, food crops won’t grow.
Farming, especially on today’s industrial scale, is tough on soil, draining essential nutrients. The most critical nutrient is nitrogen, the building block of plants. A lot of energy and money have been spent figuring out how to replace it in the soil.
In the past 50 years, led by the United States, global agriculture has come to rely increasingly on a cheap, synthetic form of nitrogen produced in fertilizer factories that are powered by natural gas and other fossil fuels.
Before World War II, when the fertilizer industry was in its infancy, farmers used very little synthetic nitrogen. By 1964, U.S. farmers were applying about 4.3 million tons annually. In 2007, the last year for which the U.S. Department of Agriculture has figures, farmers dropped 5.7 million tons on the nation’s corn crop alone. We now know that the undeniable benefits of synthetic nitrogen come with serious costs, both to the environment and to public health.
In this special Grist series, we’ll be looking at where synthetic nitrogen comes from and what our reliance on it is doing to our health and to the health of our waterways and climate. We’ll also be looking at ways in which synthetic nitrogen can be used more wisely — and, as much as possible, phased out.
The question of where our food comes from will take us on a journey from the farm out to the fertilizer factory — and even farther, to the globe’s finite and far-flung natural gas deposits. And more important than where synthetic nitrogen comes from is where it will take us.
As with anything fueling a system that feeds a nation of 300 million, there are no easy answers to the nitrogen dilemma. But we will pose the hard questions — and try to generate debate about a critical ecological issue that remains obscure and little-discussed.
Check out the first piece in the series: “The dark side of nitrogen.”
Stories in this series:
The dark side of nitrogen
Few people spare a thought for nitrogen. But with every bite we take — of an apple, a chicken leg, a leaf of spinach — we are consuming nitrogen. Plants, including food crops, can’t thrive without a ready supply of available nitrogen in the soil. The amount of food a farmer could grow was once limited by his or her ability to supplement soil nitrogen, either by planting cover crops, applying manure, or moving on to a new, more fertile field. Then, about 100 years ago, a technical innovation enabled us to produce a cheap synthetic form of nitrogen, and …
How our food system is destroying the nation’s most important fishery
To understand our impact on nature, there is truth in the saying, “everything is connected.” Few situations illustrate this concept as dramatically as the agricultural wastes from the Midwest that contribute so seriously to the aquatic dead zone in the Gulf of Mexico. Human activities and natural phenomena occurring on land masses combine to impact air quality and small-scale climate systems. Wastes and sediments flowing off lands affect natural concentrations of nutrients in water and the health of aquatic habitats. Gases suspended in air dissolve into sea water and disrupt the normal chemistry of oceans. These releases, often invisible where …
Our other addiction: the tricky geopolitics of nitrogen fertilizer
Your food doesn’t come from here, but it starts here: an ammonia factory. We burn through more of it per capita than any other country; and our appetite for it can only be sated with massive imports. No, not oil — I’m talking about nitrogen fertilizer. With only 5 percent of the world population, the U.S. consumes nearly 12 percent of the globe’s annual synthetic nitrogen fertilizer production. And we’re producing less and less of it at home — meaning that, as with petroleum, we’re increasingly dependent on other nations for this key crop nutrient. In a sense, the answer …
To reduce nitrogen pollution, we need new farm policies
California dairy farmer Joey Rocha. Photo: Stephanie OgburnTurlock, Calif. — Joey Rocha tends 2,800 cows at his Central Valley dairy. That may sound like a large herd, but in California, Rocha is a mid-sized dairy producer. Taken together, California’s dairy cows produce more than 100,000 tons of manure every day. Rocha and his fellow dairy farmers put all those cow pies to good use — as fertilizer for the fields that grow the corn that feeds their herds. It’s a perfect closed-loop system, except for one big problem: nitrogen. Manure is nitrogen rich, which makes it a great fertilizer. But …
New research: synthetic nitrogen destroys soil carbon, undermines soil health
Just precisely what does all of that nitrogen ferilizer do to the soil?“Fertilizer is good for the father and bad for the sons.”–Dutch saying For all of its ecological baggage, synthetic nitrogen does one good deed for the environment: it helps build carbon in soil. At least, that’s what scientists have assumed for decades. If that were true, it would count as a major environmental benefit of synthetic N use. At a time of climate chaos and ever-growing global greenhouse gas emissions, anything that helps vast swaths of farmland sponge up carbon would be a stabilizing force. Moreover, carbon-rich soils …
Tracking down the public-health implications of nitrogen pollution
Picture a hot summer day in California farm country, say 112 degrees. In the tiny community of Tooleville, surrounded by olive trees and orange groves, there’s one thing you won’t see here that you’d see almost anywhere else in the sunny state — kids splashing in backyard pools. “People don’t let their kids swim in pools here,” says resident Eunice Martinez. “They’re scared of what would happen if they accidentally swallow the water.” Martinez, 44, and the other 350 people who live in Tooleville haven’t been able to drink their tap water since 2003, due to unsafe levels of nitrate …
The N of an era: America’s nitrogen dilemma — and what we can do about it
There are three things on which the mighty engine of U.S. agriculture depends: water, fuel, and synthetic nitrogen. Like water, nitrogen is elemental to life. It’s the essential building block of the plants we eat. Farmers remove it from the soil when they harvest the year’s crop, and they must replenish it for the following year’s. Compared with water and fuel, nitrogen is actually in one sense quite plentiful: it makes up about 80 percent of the air we breathe. Yet for all that ubiquity, it’s also in a sense scarce: its extremely strong chemical bond — it exists in …