[I’ve reduced and paraphrased the article ]
Richard Manning. May 23, 2004. ‘The Oil We Eat’. Following the Food Chain back to Iraq. Harpers.
The journalist’s rule says: follow the money.. but money.. is really a way of tracking energy. We’ll follow the energy.
We learn as children that there is no free lunch, that you don’t get something from nothing, that what goes up must come down, and so on. The scientific version is only slightly more complex… there is only so much energy. You can change it from motion to heat, from heat to light, but there will never be more of it and there will never be less of it. The conservation of energy is not an option, it is a fact. This is the first law of thermodynamics.
Special as we humans are, we get no exemptions from the rules. All animals eat plants or eat animals that eat plants. This is the food chain [resulting from the] unique ability of plants to turn sunlight into stored energy in the form of carbohydrates, the basic fuel of all animals. Solar-powered photosynthesis is the only way to make this fuel. There is no alternative to plant energy, just as there is no alternative to oxygen.
Scientists have a name for the total amount of plant mass created by Earth in a given year: the planet’s “primary productivity.” Two [studies of this concluded that humans] consume about 40% of Earth’s primary productivity, 40% of all there is. This simple number may explain why the current extinction rate is 1,000 times that which existed before human domination of the planet. We 6 billion have simply stolen the food.
If you follow the energy, eventually you will end up in a field somewhere [two-thirds of them growing just] three plants: rice, wheat, and corn. In the 10,000 years since humans domesticated these grains, their status has remained undiminished, most likely because they are able to store solar energy in uniquely dense, transportable bundles of carbohydrates. They are to the plant world what a barrel of refined oil is to the hydrocarbon world. Indeed, aside from hydrocarbons they are the most concentrated form of true wealth–sun energy–to be found on the planet.
[In nature most plants put their energy into roots, stem, and bark to survive many seasons. There are often hundreds of species in the same area that help each other get water, protect one another from wind, and some fix nitrogen that all need to grow. Humans discovered a small number of plants (grasses mainly like corn, rice and wheat) that thrive on catastrophe by putting most of their energy into seeds so they can quickly colonize and dominate areas that were flooded or burned. Eventually other plants take over, but agriculture is like one catastrophe after another as farmers rip the earth open every season.]
It requires the equivalent of three or four tons of TNT per acre for a modern American farm. Iowa’s fields require the energy of 4,000 Nagasaki bombs every year.
When we say the soil is rich that’s not not a metaphor. Soil is as rich in energy as an oil well. A prairie converts that energy to flowers and roots and stems, which in turn pass back into the ground as dead organic matter. The layers of topsoil build up into a rich repository of energy, a bank.
Of the 40 percent of the globe’s primary productivity we use every year, a third of it, is the plant mass lost when forests are cleared for farming or when tropical rain forests are cut for grazing or when plows destroy the deep mat of prairie roots that held the whole business together, triggering erosion. The Dust Bowl was no accident of nature.
Now when [we’ve mined the soil and turned it worthless, we make the land fertile again] using oil-rich fertilizers.
It takes 5.5 gallons of fossil energy to restore 1 year of lost fertility to 1 acre of eroded land. In 1997 we burned through more than 400 years’ worth of ancient fossilized productivity.
Wheat depletion of soils caused many declines of civilizations, as there was no non-depleted soil left to grow more wheat. Wheat balances its equations with famine. In the millennium between 500 and 1500, Britain suffered a major “corrective” famine about every ten years; there were 75 in France during the same period.
The new lands had an even greater effect on the colonists themselves. Thomas Jefferson, after enduring a lecture on the rustic nature by his hosts at a dinner party in Paris, pointed out that all of the Americans present were a good head taller than all of the French. Indeed, colonists in all of the neo-Europes enjoyed greater stature and longevity, as well as a lower infant-mortality rate–all indicators of the better nutrition afforded by the onetime spend down of the accumulated capital of virgin soil.
The precolonial famines of Europe raised the question: What would happen when the planet’s supply of arable land ran out? We have a clear answer. In about 1960 expansion hit its limits and the supply of unfarmed, arable lands came to an end. There was nothing left to plow. What happened was grain yields tripled.
The accepted term for this strange turn of events is the green revolution, though it would be more properly labeled the amber revolution, because it applied exclusively to grain–wheat, rice, and corn. Plant breeders tinkered with the architecture of these three grains so that they could be hyper-charged with irrigation water and chemical fertilizers, especially nitrogen. This innovation meshed nicely with the increased “efficiency” of the industrialized factory-farm system. With the possible exception of the domestication of wheat, the green revolution is the worst thing that has ever happened to the planet.
For openers, it disrupted long-standing patterns of rural life worldwide, moving a lot of no-longer-needed people off the land and into the world’s most severe poverty. The experience in population control in the developing world is by now clear: It is not that people make more people so much as it is that they make more poor people. In the forty-year period beginning about 1960, the world’s population doubled, adding virtually the entire increase of 3 billion to the world’s poorest classes, the most fecund classes. The way in which the green revolution raised that grain contributed hugely to the population boom, and it is the weight of the population that leaves humanity in its present untenable position.
Discussion of these, the most poor, however, is largely irrelevant to the American situation. We say we have poor people here, but almost no one in this country lives on less than one dollar a day, the global benchmark for poverty. It marks off a class of about 1.3 billion people, the hard core of the larger group of 2 billion chronically malnourished people–that is, one third of humanity. We may forget about them, as most Americans do.
More relevant here are the methods of the green revolution, which added orders of magnitude to the devastation. By mining the iron for tractors, drilling the new oil to fuel them and to make nitrogen fertilizers, and by taking the water that rain and rivers had meant for other lands, farming had extended its boundaries, its dominion, to lands that were not farmable. At the same time, it extended its boundaries across time, tapping fossil energy, stripping past assets.
The common assumption these days is that we muster our weapons to secure oil, not food. There’s a little joke in this. Ever since we ran out of arable land, food is oil. Every single calorie we eat is backed by at least a calorie of oil, more like ten. In 1940 the average farm in the United States produced 2.3 calories of food energy for every calorie of fossil energy it used. By 1974 (the last year in which anyone looked closely at this issue), that ratio was 1:1. And this understates the problem, because at the same time that there is more oil in our food there is less oil in our oil. A couple of generations ago we spent a lot less energy drilling, pumping, and distributing than we do now. In the 1940s we got about 100 barrels of oil back for every barrel of oil we spent getting it. Today each barrel invested in the process returns only ten.
David Pimentel, an expert on food and energy at Cornell University, has estimated that if all of the world ate the way the United States eats, humanity would exhaust all known global fossil-fuel reserves in just over seven years.
Nitrogen can be released from its “fixed” state as a solid in the soil by natural processes that allow it to circulate freely in the atmosphere. This also can be done artificially. Indeed, humans now contribute more nitrogen to the nitrogen cycle than the planet itself does. That is, humans have doubled the amount of nitrogen in play.
This has led to an imbalance. It is easier to create nitrogen fertilizer than it is to apply it evenly to fields. When farmers dump nitrogen on a crop, much is wasted. It runs into the water and soil, where it either reacts chemically with its surroundings to form new compounds or flows off to fertilize something else, somewhere else.
That chemical reaction, called acidification, is noxious and contributes significantly to acid rain. One of the compounds produced by acidification is nitrous oxide, which aggravates the greenhouse effect. Green growing things normally offset global warming by sucking up carbon dioxide, but nitrogen on farm fields plus methane from decomposing vegetation make every farmed acre, like every acre of Los Angeles freeway, a net contributor to global warming.
Fertilization is equally worrisome. Rainfall and irrigation water inevitably washes the nitrogen from fields to creeks and streams, which flows into rivers, which floods into the ocean. This explains why the Mississippi River, which drains the nation’s Corn Belt, is an environmental catastrophe. The nitrogen fertilizes artificially large blooms of algae that in growing suck all the oxygen from the water, a condition biologists call anoxia, which means “oxygen-depleted.” Here there’s no need to calculate long-term effects, because life in such places has no long term: everything dies immediately. The Mississippi River’s heavily fertilized effluvia has created a dead zone in the Gulf of Mexico the size of New Jersey.
America’s biggest crop, grain corn, is completely unpalatable. It is raw material for an industry that manufactures food substitutes. Likewise, you can’t eat unprocessed wheat. You certainly can’t eat hay. You can eat unprocessed soybeans, but mostly we don’t. These four crops cover 82 percent of American cropland. Agriculture in this country is not about food; it’s about commodities that require the outlay of still more energy to become food.
About two thirds of U.S. grain corn is labeled “processed,” meaning it is milled and otherwise refined for food or industrial uses. More than 45% of that becomes sugar, especially high-fructose corn sweeteners, the keystone ingredient in three quarters of all processed foods, especially soft drinks, the food of America’s poor and working classes.
There is another energy matter to consider here, though. The grinding, milling, wetting, drying, and baking of a breakfast cereal requires about four calories of energy for every calorie of food energy it produces. A two-pound bag of breakfast cereal burns the energy of a half-gallon of gasoline in its making.
All together the food-processing industry in the United States uses about ten calories of fossil-fuel energy for every calorie of food energy it produces.
That number does not include the fuel used in transporting the food from the factory to a store near you, or the fuel used by millions of people driving to thousands of super discount stores on the edge of town.
We will soon buy gasoline containing twice as much fuel alcohol as it does now. Fuel alcohol already ranks second as a use for processed corn in the United States, just behind corn sweeteners. According to one set of calculations, we spend more calories of fossil-fuel energy making ethanol than we gain from it. The Department of Agriculture says the ratio is closer to a gallon and a quart of ethanol for every gallon of fossil fuel we invest. The USDA calls this a bargain, because gasohol is a “clean fuel.” This claim to cleanness is in dispute at the tailpipe level, and it certainly ignores the dead zone in the Gulf of Mexico, pesticide pollution, and the haze of global gases gathering over every farm field. Nor does this claim cover clean conscience; some still might be unsettled knowing that our SUVs’ demands for fuel compete with the poor’s demand for grain.
Green eaters, especially vegetarians, advocate eating low on the food chain, a simple matter of energy flow. Eating a carrot gives the diner all that carrot’s energy, but feeding carrots to a chicken, then eating the chicken, reduces the energy by a factor of ten. The chicken wastes some energy, stores some as feathers, bones, and other inedibles, and uses most of it just to live long enough to be eaten. As a rough rule of thumb, that factor of ten applies to each level up the food chain.
Richard Manning is the author of Against the Grain: How Agriculture Has Hijacked Civilization.