Crystal Ball EARTH: Agriculture: The future will have a different face than the past

by George A. Seielstad
Friday, January 20, 2012

U.S. Geological Survey

Tomorrow’s agriculture is facing an immense challenge. By 2050, the world’s population will reach somewhere between 9 billion and 10 billion people, and a greater proportion of those people will be enjoying a richer diet than today’s population. That means farmers will have to grow twice as much food. The world has already witnessed a preview of what might happen if large populations don’t receive an adequate supply of food: They do not accept their fates passively.

In 2007 and 2008, riots broke out in several underfed countries, including Bangladesh, Ethiopia, Haiti and Indonesia. In Haiti, the prime minister was forced out; in other countries, trust in the national governments was a casualty. Where riots occur and national governments lose their populace’s confidence, chaos arises. States that fail as a consequence become sources of terrorists, drugs, weapons and refugees. The security of civilization depends on the existence of politically organized, stable states — as a result, an adequate supply of food will be needed to assure a civilized global society.

To ensure future success, we need to make some changes in agriculture, the biggest of which will be a change in mindset. We need to rethink agriculture as not just the production of food, but also an industry central to energy production and consumption, environmental health and sustainability, global security and economic prosperity. In short, agriculture is the nexus where human and natural systems overlap. We will also need to envision agriculture as a solution to global problems, not a cause of them. This will entail long-term thinking, not just thinking about one growing season at a time.

Changing agriculture won’t be easy. For hundreds of years, increasing agricultural productivity has meant finding new land to clear, new sources of water and more potent fertilizers. But these standard practices of the past cannot be straightforwardly extrapolated into the future, as fossil fuels, water and land are growing scarce.

Industrial agriculture has relied on fossil fuels for years now, because the fuels have been both cheap and abundant. For every calorie of food energy farmers produce, they have used an order of magnitude more energy from fossil fuels — for fertilizers and pesticides, operation of field machinery, transportation and irrigation, and of course, processing, packaging and refrigerating food. But annual global consumption of oil now exceeds discoveries of new reserves, so demand will soon exceed supply, prices will rise sharply, and scarcity will be the norm. Compounding the problem is that increasing fertilizer and pesticide inputs no longer brings as great a growth in crop yields as in the past.

Agriculture also requires a lot of water, and is by far the largest user of the planet’s freshwater supply. Using rivers and other surface waters has increased so much that several major rivers — including the Colorado and Rio Grande — no longer reach the sea year-round. Exhausting vital aquifers is another problem. The Ogallala Aquifer in the Great Plains, for example, provides 30 percent of U.S. irrigation water. The amount the agricultural sector withdraws from it annually is nearly twice the aquifer’s recharge, so the water level has declined — in many places as much as 12 meters.

At the same time, growing, thirsty populations are competing with agriculture for water, straining available supplies even more. According to Rattan Lal, former president of the Soil Science Society of America, at least 30 densely populated countries, including Egypt, India, Iran, Nigeria and Tunisia, will face water shortages by 2025 — and that doesn’t include water lost due to climate change. Thus, agriculture in the future will not be able to increase yields simply by irrigating more land.

That’s also in part because there may not be a lot more land left to irrigate. Croplands and pastures already occupy 35 to 45 percent of the world’s land, and much of the remaining land is unusable for agriculture because it is at high latitudes or high altitudes. To meet the world’s growing demand for food, we would have to convert an area equal to that of the contiguous United States — an area so large that the resulting loss of nature’s many natural ecosystem services would be felt by all. Therefore, enhancing production from existing agricultural lands is preferable to continued conversion of land from natural to agricultural purposes.

Whatever changes are introduced to increase agricultural productivity will also have to reverse several other negative agricultural trends: Soil erosion, loss of soil organic matter, eutrophication of freshwater, emergence of pesticide-resistant pathogens and pests, shrinking biodiversity and climate change are environmental consequences of industrial agriculture that affect human quality of life.

Now let us consider some specific changes that I think are highly likely in the future (exactly when in the future is something I’m not too sure about).

  • Agriculture will be characterized by greater efficiencies. Inputs of every resource — water, fertilizer, pesticides, seeds — will become both site-specific and time-appropriate. No waste will be tolerated, because steeply rising costs driven by growing scarcities will create a powerful economic incentive. The accompanying reduction of runoff of excessive chemicals will be part of the problem-solving character of tomorrow’s agriculture.

  • Farming will be mostly no-till. By minimizing soil’s exposure to oxidation and by leaving residues on the ground, soil organic matter will be preserved and recycled. Because carbon is the key element of soil organic matter, soil’s ability to increase soil organic matter coincides with its need to capture carbon from the atmosphere. Soon, we will find a method for quantifying how much carbon is actually sequestered in soil and for how long, depending on the particular agricultural practice.

    As national policies that reward practices that remove climate-changing carbon dioxide from the atmosphere emerge, agriculture will acquire another source of income and environmental restoration. No-till agriculture additionally enhances water retention, thereby reducing the demand for irrigation water. Moreover, it conserves energy because of no-till’s reduction in farm machinery traffic.

  • Wetlands and riparian areas near agricultural fields will be additional targets for environmental restoration. This preservation will recharge aquifers and filter agricultural pollutants, preventing them from reaching waterways and aquifers.

  • Recycling and reuse will become standard practice. Returning nutrients to the soil will be essential. Phosphorus is a prime example of a finite resource — it’s currently mined from only a few locations — that must be reused, both because it will become ever scarcer (and therefore expensive) and because it is a major cause of freshwater eutrophication. All the inedible biomass left over after harvest will be left on fields so it can return its nutrients to the soil. Animal waste, including bones, from meat and dairy production will also be applied to the soil. So-called wastewater will need to be recycled as well.

  • Production of meat will likely decline. In the United States, approximately 10 tons of grain are needed to raise one ton of beef. Each ton of grain requires about 1,000 tons of water. In addition, 450 gallons of oil are consumed to produce that ton of meat. Scarcities of water, land and oil, clashing head-on with the need for increased food supplies, will limit the luxury of meat-rich diets.

  • Agriculture will be just one among several major industries encountering eco-economics, forcing a new kind of accounting upon society. Total costs and benefits — including environmental consequences — will be evaluated in establishing prices. In agriculture, practices that enhance ecosystem services and public health will be rewarded monetarily, while those that damage them will be assessed appropriate costs.

One change that analysts often predict for the future, especially in the United States, seems unlikely: the use of scarce resources to produce biofuels instead of food. Agriculture today is a global activity; no country is self-sufficient in the food its residents consume. So no nation can escape consideration of the global impacts of its decisions. Presently, approximately a billion people are so malnourished they cannot live productive lives. Some of the countries in which they live have rapidly growing populations. Doubling the food supply will be difficult enough without compounding the difficulty by using productive lands to grow biofuels. The amount of grain needed to fill a 25-gallon fuel tank would feed one person for a year.

Global stability and perpetuation of civilized societies are not issues to regard lightly. I think the changes I detail above must be made to assure a peaceful, secure world. The changes are likely to happen. The only question is how quickly. Time is a luxury we do not have. We will have to muster enormous political will to encourage the necessary changes, and that will emerge only if all of us commit to its necessity.

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