PRESIDENT'S LETTER

Rob McClung

Let Them Eat Cake? One Dickens of a Dilemma

It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair, we had everything before us, we had nothing before us, we were all going direct to heaven, we were all going direct the other way—in short, the period was so far like the present period, that some of its noisiest authorities insisted on its being received, for good or for evil, in the superlative degree of comparison only.

—Charles Dickens, A Tale of Two Cities

A French proverb says, “The more things change, the more they stay the same.” Much has changed from the revolutionary France of Dickens’s novel, yet we still encounter food shortages and the riots these shortages engender. A meeting in Washington, D.C., of economic ministers in mid-April of this year has drawn considerable attention to the newest iteration of this age-old problem (1).

Food shortages and increasing prices this year have contributed to political instability in many countries, including Haiti, Egypt, the Philippines, and Indonesia. According to the World Bank, global food prices have increased by 83% in the past three years. In Haiti, 80% of the population lives on less than $2 per day, and the cost of many staple foods has increased 50% in the past year alone (2). So far this year, the price of rice, a staple in the diets of nearly half the world’s population, has almost doubled on international markets (3). In response, a number of countries (Cambodia, Egypt, India, Vietnam) have put restrictions or outright bans on rice exports.

Robert Zoellick, president of the World Bank, warned that many (more than 30) nations are at risk of social unrest because of the rising prices of food. He said, “For countries where food comprises from half to three-quarters of consumption, there is no margin for survival.” In some countries, the vast majority of people’s income is devoted to food. In Indonesia, this proportion is 50%, in Vietnam it is 65%, and in Nigeria it is 73%! In the United States, that figure is much less (about 10% nationally, and reaching only 16% among the poorest 20% of the population). Nonetheless, even in the United States, there is concern because food banks are depleted, and even school lunch programs are suffering.

The recent food riots in Haiti contributed to the dismissal of the prime minister. The economic ministers declared at their meeting that food shortages pose a potentially greater threat to economic and political stability than the turmoil in capital markets!

At one level, this is a story we’ve heard before, but we should pay close attention, as there are some new twists to the story that affect us as plant biologists.

What has caused these food shortages and the rapidly increasing prices? As one might suspect for any problem of this magnitude, there are many contributing factors. One is weather—the recent drought in Australia has had a serious adverse impact on the wheat crop. Global economic expansion has given many people access to better diets that include more meat, which has increased demand for grains as animal feed. Of course, oil prices surpassing $118 per barrel (on April 22, Earth Day) raise costs of crop production and distribution.

As plant biologists, we know we must address the challenges of raising more food on less land that is subjected to increased environmental stress. New to this discussion of food shortage and price increase is the identification by the conference of economic ministers of the increased production of ethanol and other biofuels as a contributing factor.

Both Rick Amasino and I have spoken of biofuels in this space, identifying them as an important component of energy supplies that are greener because of, among other attributes, sustainability and reduced greenhouse gas (GHG) emissions. Now, though, critics of expanded biofuels production are linking increased biofuels production with food scarcity and increased food prices. There are calls to reconsider policies to expand biofuels production (4).

The extent to which the demand for biofuels has contributed to the rise in food prices is not clear. Work by the International Food Policy Research Institute suggests that biofuel production accounts for 25% to 30% of the recent increase in global commodity prices (5). The Food and Agriculture Organization of the United Nations took a more moderate view, estimating late last year that biofuels production, assuming that current mandates continue, would increase food costs by 10% to 15%. Such analyses are fraught with hazard, both as predictions and even in hindsight, because the accounting is extremely complex.

It seems intuitively obvious that conversion of food into fuel offers a direct competition with food supply. Replacing fields of food crops with fields of nonfood biofuel feedstocks renders that competition only slightly more indirect. In addition, it seems equally obvious that those at the bottom of the world’s economic ladder will be the most vulnerable to decreases in food availability and increases in cost. For example, an editorial in Nature (6) cited World Bank studies as indicating that for the poorest people in the world, a 1% increase in the price of staple food leads to a 0.5% drop in caloric consumption.

In the United States, corn is the bioethanol crop of the day, while elsewhere sugar cane and sugar beet are major sources of the sugars for fermentation. There are a number of arguments that ethanol from corn is not a desirable solution in the long term. The substantial energy inputs associated with corn production in the developed world greatly reduce the net energy gain associated with ethanol produced from corn to about 20%. Excessive nutrient (nitrogen and phosphorus) inputs and subsequent runoff have substantial negative implications for water quality (7). Nitrogen fertilizer is a key source of the potent greenhouse gas nitrous oxide.

Estimates of energy gain and associated GHG emissions are highly sensitive to underlying assumptions. For example, the GHG emissions associated with ethanol production from corn are extremely sensitive to the choice of process fuel, with one study calculating a net increase of 3% for coal and a net decrease of 53% for wood chips (8). Widespread adoption of no-till agriculture in corn and soybean farming, and inherent in adoption of perennial grasses, would convert agricultural lands into a net carbon sink (9). However, it has been argued that the conversion of forests and grasslands to biofuel farms growing either corn or switchgrass greatly increases GHG emissions, because the organic carbon stored as plant biomass and in soils is released following clearing and conversion to agricultural use (10, 11, 12).

These calculations are sensitive to assumptions about the use of the cleared materials. For example, firewood, including that derived from lands cleared for biofuels production, is used to replace oil for the drying and processing of virtually all of the Brazilian soybean crop (61 million tons), with concomitant reduction of GHG emission. Similarly, analyses of the energy gains associated with ethanol from corn are dramatically affected by consideration of products of ethanol production from corn, including dried distiller grains, corn gluten feed, and corn oil (13).

It is widely predicted that cellulosic biomass (so-called second-generation biofuels) will eventually offer considerably more favorable energy yields and GHG emissions than corn (14). For example, Miscanthus, a perennial grass being investigated as a cellulosic biomass crop, effectively sequesters carbon in the soil at rates of 0.5 t [C] per hectare per year (15, 16) and yields more than 2.5 times as much ethanol per hectare as corn. Lignocellulosic materials make up the majority of the cheap and abundant nonfood materials available (17). However, both production of lignocellulosic biomass and its processing into ethanol are extremely new, and many advances are necessary before the potential of this route can be realized (18).

More data are needed, as many of the estimates of energy gains and GHG emissions are based on modeling, and we need solid experimental data to substantiate the assumptions upon which the models rest. As scientists, we have the responsibility to generate these data and to use them to inform our elected policymakers. Critically, we need good and fair accounting in which assumptions and system boundaries are apparent and realistic.

Significant sums of research dollars are being made available for research into all aspects of biofuels. For many aspects of plant research, these are the best of times. Has plant science lost sight of the world’s poorest, for whom these are the worst of times? I do not think so. Most major biofuels research initiatives have deliberately targeted nonfood crops to avoid even the appearance of a food versus fuels competition. Where the work has addressed grain crops, it is not the grain but the stover that is targeted for biofuels. Moreover, a major effort is to develop biofuels crops that can be grown on land not currently used for food production.

One common currency between food and fuels is crop production, so increases in productivity can allow both food and biofuel. The theoretical maximum energy conversion efficiency of plants is 6%, and crops worldwide average 0.1% to 0.2% (19), offering an opportunity and a challenge for plant biology.
Over the past few decades, the plant research community has made enormous progress in understanding basic and agronomic topics such as photosynthesis and water use efficiency. New and powerful tools of genome research and systems and synthetic biology will aid current efforts to adapt crops to specific environments and in response to global climate change. For many reasons, biofuels remain an attractive source of fuel. However, we cannot wash our hands of our responsibility to the world’s poor and vulnerable. Can we have both food and biofuel? We can, and one route to that goal is to emphasize research to increase plant production. All will benefit.
I would like to thank Andy Friedland (Dartmouth College) and Steve Long (University of Illinois) for useful comments on this letter.

Rob McClung
c.robertson.mcclung@dartmouth.edu

References

1. Weisman, S. R. 2008. Finance ministers emphasize food crisis over credit crisis. New York Times, April 14.
2. World Briefing: The Americas; Haiti: Thousands protest food prices. 2008. New York Times, April 8.
3. Bradsher, K. 2008. High rice cost creating fears of Asia unrest. New York Times, March 29.
4. Martin, A. 2008. Fuel choices, food crises and finger-pointing. New York Times, April 15.
5. von Braun, J. 2008. Rising food prices: What should be done? http://www.ifpri.org/pubs/bp/bp001.asp.
6. Kill king corn. 2007. Nature 449:637. DOI 10.1038/449637a.
7. Schnoor, J. L., O. C. Doering III, D. Entekhabi, E. A. Hiler, T. L. Hullar, G. D. Tilman, W. S. Logan, N. Huddleston, and M. Stoever. 2008. Water implications of biofuels production in the United States. Washington, DC: National Academies Press. http://books.nap.edu/catalog.php?record_id=12039.
8. Wang, M., M. W. Hong, and H. Huo. 2007. Life-cycle energy and greenhouse gas emission impacts of different corn ethanol plant types. Environmental Research Letters 2. DOI 10.1088/1748-9326/2/2/024001.
9. Bernacchi, C. J., S. E. Hollinger, and T. Meyers. 2005. The conversion of the corn/soybean ecosystem to no-till agriculture may result in a carbon sink. Global Change Biology 11:1867–1872.
10. Fargione, J., J. Hill, D. Tilman, S. Polasky, and P. Hawthorne. 2008. Land clearing and the biofuel carbon debt. Science 319:1235–1238.
11. Searchinger, T., R. Heimlich, R. A. Houghton, F. Dong, A. Elobeid, J. Fabiosa, S. Tokgoz, D. Hayes, and T. Yu. 2008. Use of U.S. croplands for biofuels increases greenhouse gases through emissions from land-use change. Science 319:1238–1240.
12. Grunwald, M. 2008. The clean energy myth/scam. Time Magazine, April 7.
13. Farrell, A. E., R. J. Plevin, B. T. Turner, A. D. Jones, M. O’Hare, and D. Kammen. 2006. Ethanol can contribute to energy and environmental goals. Science 311:506–508.
14. Gomez, L. D., C. G. Steele-King, and S. J. McQueen-Mason. 2008. Sustainable liquid biofuels from biomass: the writing’s on the walls. New Phytologist 178:473–485.
15. Clifton-Brown, J. C., J. Breuer, and M. B. Jones. 2007. Carbon mitigation by the energy crop, Miscanthus. Global Change Biology 13:2296–2307.
16. Schneckenberger, K., and Y. Kuzyakov. 2007. Carbon sequestration under Miscanthus in sandy and loamy soils estimated by natural C-13 abundance. Journal of Plant Nutrition and Soil Science 170:538–542.
17. U.S. Department of Energy. 2006. Breaking the biological barriers to cellulosic ethanol: A joint research agenda. http://genomicsgtl.energy.gov/biofuels/2005workshop/b2blowres63006.pdf.
18. Lynd, L. R., M. S. Laser, D. Bransby, B. E. Dale, B. Davison, R. Hamilton, M. Himmel, M. Keller, J. D. McMillan, J. Sheehan, and C. E. Wyman. 2008. How biotech can transform biofuels. Nature Biotechnology 26:169–172.
19. Zhu, X. G., S. P. Long, and D. R. Ort. 2008. What is the maximum efficiency with which photosynthesis can convert solar energy into biomass? Current Opinion in Biotechnology 19:153–159.