Comment pubs.acs.org/est
How to Feed 10 Billion?
W
undernourished person. Averaging the calorific intake of a starving person with one who is obese is not the calculus we are striving for here. Perhaps we should rephrase the question, “How will we feed the malnourished 850 million”? That is why the world’s resolve is of prime importance to reinforce the U.N. Millennium Development Goals with a new round of objectives. All things considered, I have been influenced by the FAO report to believe it is possible to accomplish the goal of feeding the world in 2050. A growth in agricultural production of at least 60% will be needed, while population is projected to increase by only 37% during the same period, 2005−2050. Let us hope we live as enlightened vegetarians, that governments rethink the use of food crops for biofuels, and that climate change brings only gentle rainfall and soft breezes to our land.
as Malthus ultimately right (but simply off by a couple hundred years)? How do we feed 10 billion people projected for the middle to the end of the 21st century? Or even the U.N. best estimate of 9.2 billion by 2050? These questions beg to define a “carrying capacity” for planet earth. If food is an essential element for life and the amount of arable land is fixed, while the population continues to grow, how do we produce enough food for everyone? Until now, food produced per capita has continuously increased, allowing the average diet on planet earth to actually improve and the number of hungry and malnourished to decline. But recent data indicate that humanity’s long increase in food production per capita could be coming to an end. Ironically, it comes down to a race between declining rates of population growth and declining rates of agricultural production growth. If we ask the question, “How many people can the world feed?” We must also ask, “At what level of consumption?” And perhaps additionally, “How are you going to grow the food, where will it be grown, and at what damage to the soil and the environment?” According to Lester Brown (World on the Edge, Earth Policy Institute, 2011) the answer to “How many people can the world feed,” is the following. If we live like an American, we could feed 2.5 billion. But to live at the level of people in India, we could probably feed 10 billion. That is because it takes 8 kg of grain to produce 1 kg of beef, and 3−4 kg grain to produce 1 kg of pork, 2 kg/kg for poultry, and perhaps as little as 1 kg of grain to grow 1 kg of carp via aquaculture. Clearly, aquaculture could be an important strategy to feed 10 billion people in 2050, and China is leading the way. Another answer to the question involves government policyit is counterproductive to use arable land to grow biofuels if we want to feed 10 billion. Fifteen percent of global corn production (129 million metric tons per year) is going to make biofuels. In the U.S., 40% of the corn crop is dedicated to ethanol. But while using 40% of the corn crop (35 million acres), we replace a mere 10% of the transportation fuel in the U.S. Simply put, it just takes too much land to grow a substantial volume of biofuels. Food is a more precious and valued commodity. Growing cellulosic feedstocks on marginal land may be viable, but biofuels must not displace food crops in countries where food security is an issue. And there remain 850 million people in locations where it is. Climate change is another unknown affecting the goal of feeding 10 billion. If the climate alters our ability to produce foodparticularly in sub-Saharan Africa, south Asia, and Latin Americaour prospects for feeding the world go dry. Climate change affects the lives of people who are most vulnerable and least resilient to its ravages. In recent years, our global average caloric intake rose to a respectable 2770 kcal/person/day in 2005/07 (Alexandratos and Bruinsma, World Agriculture Toward 2030/2050: The 2012 revision, FAO). Country-bycountry and commodity-by-commodity projections indicate that this quantity could rise to 3070 kcal/person/day by 2050. But it is not the global average that matters to an © 2013 American Chemical Society
■
Jerald L. Schnoor, Editor-in-Chief AUTHOR INFORMATION
Corresponding Author
[email protected]. Notes
Views expressed in this editorial are those of the author and not necessarily the views of the ACS. The authors declare no competing financial interest.
Published: December 18, 2013 1361
dx.doi.org/10.1021/es4052507 | Environ. Sci. Technol. 2014, 48, 1361−1361
