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Arable Land and Topsoil

"Soil is the gut of the earth, the principal digestive organ of planetary life. Soil is partially composed of rock chips, clay, sand, minerals, and organic detritus, but it is also an interdependent living community of micro-organisms, insects, worms, small animals, reptiles, and other organisms which live in, contribute to and feed on components of the soil. Like the bacteria community in the human gut that predigests the human food, the soil is a living community of organisms which produces the necessary conditions for the plant communities to exist."-William H. Kötke, The Final Empire.

All most all of our production of food occurs on the land. Arable land, land that is suitable for growing edible plants, is already at a premium, to the extent that using rooftops and tiny backyard city plots have become part of the discussion for maintaining food supplies. As our population has grown and our quantity of arable land has not, we have been forced to increase yield, that is, product per acre, to keep up with demand. To do this we have turned to industrial agriculture and monoculture, primarily in the grain families. These methods have proven wasteful in terms of topsoil loss, water quality, and energy input. The way we farm must change and the variety of the foods we eat must widen.

Arable Land

Grain, a term that generally includes wheat, corn, rice, barley, oats, and sorghum, serves as the basic foodstuff, either on the table or for raising animal protein sources, for the majority of Earth's population. This became increasingly so during the nineteenth century when the industrial age entered into full bloom and the rural populace started a steady migration to burgeoning industrial locales. Because grain could be stored for long periods of time without refrigeration and transported in relatively easy-to-handle bulk, it was the most efficient and cheapest way to feed the collecting urban masses. The demand for bread from the industrializing cities of Europe and the eastern United States pushed open the vast North American prairies to wheat and corn farming.1 With the great expanses of farmland in the United States and Canada, it seemed for well over a hundred years that the world had an inexhaustible bread basket.

Unfortunately, in the last thirty years industry's voracious appetite has caught up with Earth's "inexhaustible" reserve of arable land. The most obvious reason for this is the building of homes and factories and roads that take much of the prime land from seed. Not so obvious is that industrialization has changed the way we farm. As the growing metropolis draws people from rural areas and farming occupations, the many small farms become fewer large farms. Multi-crop truck farms become mono-culture plantations. Industrial agriculture replaces family farming.

While large industrial farms are more productive regarding overall yield, and may even be the only way to supply the quantity of grain needed to feed the huge cities of today's world, because it depends heavily on nonrenewable fossil fuels and is extremely costly in terms of topsoil loss and chemical waste, industrial agriculture represents the antithesis of sustainable farming. If population conitnues to increase at the rate of one percent annually and arable land decreases at that same annual rate, our current methods of food production will be leading to a dead end.

In the equation of food production, topsoil is just as critical as expanses of open land. Without decent topsoil, land is little more than desert. Topsoil is literally the living surface from which terrestrial life arises. Not only is it composed of rock chips, clay, sand, minerals and organic detritus, but it is also an interdependent living community of insects, worms, and other micro-organisms that contribute to the vitality of the soil.2

Industrial agriculture amounts to a literal mining of this topsoil, that is, a drawing up of the soil's nutrients through edible biota. Gradually, crop after crop, the soil is depleted of its minerals, nutrients, and organisms, which are then replaced with petrochemical substitutes.

On a properly husbanded farm or in nature, the soil is fertilized organically from the waste products of what lives on it; the soil sustains as a living, breathing thing. On a large commercial farm, petrochemical fertilizers are invested in depleted soil with each new crop. When the ground is open and heavily worked with chemical additives, especially in large flat expanses, though filled with nitrogen and phosphates, it becomes dead and lifeless. The microbes are gone. The organisms die. The topsoil erodes rapidly with the weather and is washed away with the wind and the flush of water. Over time, the soil eventually finds its way to the mouth of the nearest river. This is occurring at alarming rates all over the world. "The Yellow River in China carries 1.6 billion tons of soil to the ocean annually."3 The Ganges of India...deposits "1.5 billion tons of soil into the Bay of Bengal each year. The Mississippi, the largest U.S. river, carries 300 million tons of soil into the Gulf of Mexico yearly."4

This loss of topsoil is an egregious insult against the land and the life on it. Topsoil accumulates very slowly in nature, as little as an inch every five hundred years.5 Rebuilding it, even with composting, natural additives, and crop rotation, can take decades of dedicated effort.

While the techniques of large-scale farming have enabled dramatic yield increases, declining fossil fuel resources and related price increases, add to its unsustainability. Petrochemical fertilizers, herbicides, pesticides, and diesel fuel are heavily invested in the industrial farming process. In turn, the conveyor belt of the food processing industry relies on diesel powered trucks, plastic packaging, and other fossil fuel products to get the food to our table. This dependence on fossil fuels further jeopardizes food security. The global food network will soon have to be radically relocalized to help cut petroleum costs from the food equation.

In addition to the lost of arable land to road building and suburban expansion, industrial society's higher standard of living changes what and how we eat in ways that further cut into available crop land. Of course, we are all seeking a better life, but when we are talking about the trade-off between population and resources, any balance we seek must be a function of the way that population lives and consumes. As things stand today, less than a fifth of the population lives at or near the standards of middleclass America. It is doubtful that even two billion people could inhabit the earth sustainably living at the high standard set in the United States, and yet that is precisely what the rest of the world is striving to do.

Economic development produces a heavier, more varied diet, an American cuisine, if you will. It is rich in poultry, beef, pork, dairy products, and fish. The raising of farm animals or fish through aquaculture is land intensive. There must be space for the animals or fish to live, large stockyards or grazing land or man-made ponds. They must also be fed, invariably grain or soy products. Because it takes seven tons of grain to produce one ton of beef (three for pork, two for poultry), the higher standard trades grain land for a richer diet. If we start using more land to produce corn for ethanol, we make an even more luxurious trade-off, grain land for fuel.

The use of arable land is directly proportional to the number of mouths to feed and how much and what kind of food they eat. Beef, of all meat products, is the most costly, not just because of its one to seven trade-off for grain, but because its high-market value causes ranchers to make critical economic choices over environmental ones. Short-term economic rationale says use the land in a way that produces the highest profit. Thus grain land is turned into grazing land or, in some Third World countries, coffee or banana plantations for export value. These are not necessarily the best long-term choices when ton for ton food production will need to be maximized if population pressure don't recede.

The Amazon basin is a prime example. Its rain forests account for the cleansing of nearly a quarter of the world's water–a tremendous priority. Yet large areas of rainforest in Brazil have been deforested to open pasture for cattle. Usually grazing animals' eating patterns are adapted to their locale, their ecological niche. What each grazing animal consumes serves a particular purpose in that niche. Moving ruminating herds to foreign or artificially created range land means their diet is not attuned to the location. They have no such selectivity of eating. They graze through natural barriers and thus become one of the most expensive uses of land there is for food production. Aside from polluting local water supplies with their manure when they are not properly fenced and their methane contribution to global warming, these veritable hoofed locust are an ecological disaster in themselves.6 When herds are large and grazing patterns are not well-managed, they literally eat everything from the surface of the land, leading to the complete elimination of the ecology. In the Brazilian rain forest, human deforestation by fire is followed by this scorched earth grazing. In the end, the land is left open to heavy erosion and an eventual fate as wasteland.

All total, through industrial sprawl, industrial monoculture, and more affluent eating styles, we are trimming our options for the future. Management of planet earth must include optimization of cropland, conservation of topsoil, and a moving away from petrochemical farming. Along with changing the way we farm and turning to organic farming, conservation tillage, or permaculture, expanding our dietary choices is another way to increase food security. "There are at least five thousand plants that have been used for human consumption on the planet yet the civilized diet is made up from less than ten types of plants."7 Increasing the number of plants in our diet, increases the types of land available for farming, increases the ways crop rotation can add to the health of the land, and increases the variety of nutriments we receive in our daily diet. When the tough choices need to be made, once again we face the question of decreasing population or changing the way we eat and farm.

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