Did you know? The heat in the upper six miles of the earth’s crust contains 50,000 times much as energy as found in all the world’s oil and gas reserves combined. Despite this abundance, only 10,500 megawatts of geothermal generating capacity have been harnessed worldwide. For more information view the text and data in Chapter 5 of Plan B 4.0: Mobilizing to Save Civilization.
Chapter 9. Feeding Eight Billion People Well: Producing Protein More Efficiently
Another way to raise both land and water productivity is to produce animal protein more efficiently. With some 36 percent (750 million tons) of the world grain harvest used to produce animal protein, even a modest gain in efficiency can save a large quantity of grain. 37
World meat consumption increased from 44 million tons in 1950 to 260 million tons in 2007, more than doubling annual consumption per person from 17 kilograms to 39 kilograms (86 pounds). Consumption of milk and eggs has also risen. In every society where incomes have risen, so has meat consumption, reflecting a taste that evolved over 4 million years of hunting and gathering. 38
As both the oceanic fish catch and the production of beef on rangelands have leveled off, the world has shifted to grain-based production of animal protein to expand output. Within the meat economy, both health concerns and price differences are shifting consumer demand from beef and pork to poultry and fish, sources that convert grain into protein most efficiently.
The efficiency with which various animals convert grain into protein varies widely. With cattle in feedlots, it takes roughly 7 kilograms of grain to produce a 1-kilogram gain in live weight. For pork, the figure is over 3 kilograms of grain per kilogram of weight gain, for poultry it is just over 2, and for herbivorous species of farmed fish (such as carp, tilapia, and catfish), it is less than 2. As the market shifts production to the more grain-efficient products, it raises the productivity of both land and water. 39
Global beef production, most of which comes from rangelands, grew less than 1 percent a year from 1990 to 2007. Growth in the number of cattle feedlots was minimal. Pork production grew by 2 percent annually, and poultry by nearly 5 percent. World pork production, nearly half of it now in China, overtook beef production in 1979 and has continued to widen the lead since then. The growth in poultry production from 41 million tons in 1990 to 88 million tons in 2007 enabled poultry to eclipse beef in 1995, moving into second place behind pork. 40
Fast-growing, highly grain-efficient world fish farm output may also overtake world beef production in the next few years. In fact, aquaculture has been the fastest-growing source of animal protein since 1990, largely because herbivorous fish convert feed into protein so efficiently. Aquacultural output expanded from 13 million tons in 1990 to 50 million tons in 2007, growing by more than 8 percent a year. 41
Public attention has focused on aquacultural operations that are environmentally inefficient or disruptive, such as the farming of salmon, a carnivorous species, and shrimp. These operations account for slightly more than 10 percent of the world’s farmed fish output. Salmon are inefficient in that they are fed other fish, usually as fishmeal, which comes either from fish processing wastes or from low-value fish caught specifically for this purpose. Shrimp farming often involves the destruction of coastal mangrove forests to create areas for the shrimp. Farming salmon and shrimp in offshore ponds concentrates waste, contributing to eutrophication and dead zone creation. 42
Worldwide, however, aquaculture is dominated by herbivorous species—mainly carp in China and India, but also catfish in the United States and tilapia in several countries—and shellfish. This is where the great growth potential for efficient animal protein production lies.
China accounts for 62 percent of global fish farm production. Its output is dominated by finfish (mostly carp), which are grown in inland freshwater ponds, lakes, reservoirs, and rice paddies, and by shellfish (mostly oysters, clams, and mussels), which are produced mostly in coastal regions. 43
Over time, China has developed a fish polyculture using four types of carp that feed at different levels of the food chain, in effect emulating natural aquatic ecosystems. Silver and bighead carp are filter feeders, eating phytoplankton and zooplankton respectively. The grass carp, as its name implies, feeds largely on vegetation, while the common carp is a bottom feeder, living on detritus. These four species thus form a small ecosystem, each filling a particular niche. This multi-species system, which converts feed into high-quality protein with remarkable efficiency, allowed China to produce some 14 million tons of carp in 2007. 44
While poultry production has grown rapidly in China, as in other developing countries, it has been dwarfed by the phenomenal growth of aquaculture. Today aquacultural output in China—at 31 million tons—is double that of poultry, making it the first large country where fish farming has eclipsed poultry farming. 45
China’s aquaculture is often integrated with agriculture, enabling farmers to use agricultural wastes, such as pig or duck manure, to fertilize ponds, thus stimulating the growth of plankton on which the fish feed. Fish polyculture, which commonly boosts pond productivity over that of monocultures by at least half, is widely practiced in both China and India. 46
With incomes now rising in densely populated Asia, other countries are following China’s aquacultural lead. Among them are Thailand and Viet Nam. Viet Nam, for example, devised a plan in 2001 of developing 700,000 hectares of land in the Mekong Delta for aquaculture, which now produces more than 1 million tons of fish and shrimp.47
In the United States, catfish are the leading aquacultural product. U.S. annual catfish production of 515 million pounds (1.6 pounds per person) is concentrated in the South. Mississippi, with half the country’s output, is the U.S. catfish capital. 48
When we want high-quality protein, we typically look to soybeans, as either tofu, veggie burgers, or other meat substitutes. But most of the world’s fast-growing soybean harvest is consumed indirectly in the beef, pork, poultry, milk, eggs, and farmed fish that we eat. Although not a visible part of our diets, the incorporation of soybean meal into feed rations has revolutionized the world feed industry.
In 2008, the world’s farmers produced 213 million tons of soybeans—1 ton for every 10 tons of grain produced. Of this, some 20 million tons were consumed directly as tofu or meat substitutes. The bulk of the remaining 193 million tons, after some was saved for seed, was crushed in order to extract 36 million tons of soybean oil, separating it from the highly valued, high-protein meal. 49
The 150 million or so tons of protein-rich soybean meal that remain after the oil is extracted are fed to cattle, pigs, chickens, and fish. Combining soybean meal with grain in roughly one part meal to four parts grain dramatically boosts the efficiency with which grain is converted into animal protein, sometimes nearly doubling it. The world’s three largest meat producers—China, the United States, and Brazil—now all rely heavily on soybean meal as a protein supplement in feed rations. 50
The heavy use of soybean meal to boost the efficiency of feed use helps explain why the share of the world grain harvest used for feed has not increased over the last 20 years even though production of meat, milk, eggs, and farmed fish has climbed. It also explains why world soybean production has increased 13-fold since 1950. 51
Mounting pressures on land and water resources have led to the evolution of some promising new animal protein production systems that are based on roughage rather than grain, such as milk production in India. Since 1970, India’s milk production has increased fivefold, jumping from 21 million to 106 million tons. In 1997 India overtook the United States to become the world’s leading producer of milk and other dairy products. 52
The spark for this explosive growth came in 1965 when an enterprising young Indian, Verghese Kurien, organized the National Dairy Development Board, an umbrella organization of dairy cooperatives. The dairy co-op’s principal purpose was to market the milk from tiny herds that typically averaged two to three cows each, thus providing the link between the growing market for dairy products and the millions of village families who each had only a small marketable surplus. 53
Creating the market for milk spurred the fivefold growth in output. In a country where protein shortages stunt the growth of so many children, expanding the milk supply from less than half a cup per person a day 30 years ago to nearly one cup today represents a major advance. 54
What is so remarkable is that India has built the world’s largest dairy industry almost entirely on crop residues—wheat straw, rice straw, and corn stalks—and grass gathered from the roadside. Even so, the value of the milk produced each year now exceeds that of the rice harvest. 55
A second new protein production model, one that also relies on ruminants and roughage, has evolved in four provinces in eastern China—Hebei, Shangdong, Henan, and Anhui—where double cropping of winter wheat and corn is common. Although wheat straw and cornstalks are often used as fuel for cooking, villagers are shifting to other sources of energy for this, which lets them feed the straw and cornstalks to cattle. 56
These four crop-producing provinces in China, dubbed the Beef Belt by officials, use crop residues to produce much more beef than the vast grazing provinces in the northwest do. The use of crop residues to produce milk in India and beef in China lets farmers reap a second harvest from the original grain crop, thus boosting both land and water productivity. Similar systems can be adopted in other countries as population pressures intensify, as demand for meat and milk increases, and as farmers seek new ways to convert plant products into animal protein. 57
The world desperately needs new more-efficient protein production techniques such as these. Meat consumption is growing almost twice as fast as population, egg consumption is growing more than twice as fast, and growth in the demand for fish—both from the oceans and from fish farms—is also outpacing that of population. 58
While the world has had decades of experience in feeding an additional 70 million people each year, it has no experience with some 3 billion people striving to move up the food chain. For a sense of what this translates into, consider what has happened in China, where record economic growth has in effect telescoped history, showing how rapidly diets change when incomes rise. As recently as 1978, meat consumption in China consisted mostly of modest amounts of pork. Since then, consumption of meat, including pork, beef, poultry, and mutton, has climbed severalfold, pushing China’s total meat consumption far above that of the United States. 59
37. USDA, PS&D, op. cit. note 1.
38. FAO, 1948–1985 World Crop and Livestock Statistics (Rome: 1987); FAO, op. cit. note 10; U.N. Population Division, op. cit. note 3.
39. Conversion ratio for feed-to-poultry derived from data in Robert V. Bishop et al., The World Poultry Market—Government Intervention and Multilateral Policy Reform (Washington, DC: USDA, 1990); beef based on Allen Baker, Feed Situation and Outlook staff, ERS, USDA, discussion with author, 27 April 1992; pork from Leland Southard, Livestock and Poultry Situation and Outlook staff, ERS, USDA, discussion with author, 27 April 1992; fish from Rosamond Naylor et al., “Effect of Aquaculture on World Fish Supplies,” Nature, vol. 405 (29 June 2000), pp. 1,017–24.
40. FAO, op. cit. note 10.
41. FAO, FISHSTAT Plus, electronic database, at www.fao.org, updated February 2009; Naylor et al., op. cit. note 39.
42. FAO, op. cit. note 41; Taija-Riitta Tuominen and Maren Esmark, Food for Thought: The Use of Marine Resources in Fish Feed (Oslo: WWF-Norway, 2003); Rosamond Naylor and Marshall Burke, “Aquaculture and Ocean Resources: Raising Tigers of the Sea,” Annual Review of Environmental Resources, vol. 30 (November 2005), pp. 185–218.
43. FAO, op. cit. note 41.
44. S. F. Li, “Aquaculture Research and Its Relation to Development in China,” in World Fish Center, Agricultural Development and the Opportunities for Aquatic Resources Research in China (Penang, Malaysia: 2001), p. 26; FAO, op. cit. note 41.
45. FAO, op. cit. note 10; FAO, op. cit. note 41.
46. Naylor et al., op. cit. note 39; W. C. Nandeesha et al., “Breeding of Carp with Oviprim,” in Indian Branch, Asian Fisheries Society, India, Special Publication No. 4 (Mangalore, India: 1990), p. 1.
47. “Mekong Delta to Become Biggest Aquatic Producer in Vietnam,” Vietnam News Agency, 3 August 2004; “The Mekong Delta Goes Ahead with the WTO,” Vietnam Economic News Online, 8 June 2007; FAO, op. cit. note 41.
48. Naylor et al., op. cit. note 39; FAO, op. cit. note 41; USDA, NASS, Catfish Production (Washington, DC: 30 January 2009), pp. 17–20; U.N. Population Division, op. cit. note 3.
49. USDA, Foreign Agricultural Service, Oilseeds: World Markets and Trade (Washington, DC: May 2009).
50. USDA, PS&D, op. cit. note 1.
51. Historical data from USDA, in Worldwatch Institute, op. cit. note 18; USDA, PS&D, op. cit. note 1.
52. FAO, op. cit. note 10.
53. S. C. Dhall and Meena Dhall, “Dairy Industry—India’s Strength in Its Livestock,” Business Line, Internet Edition of Financial Daily, Hindu group of publications, 7 November 1997; see also Surinder Sud, “India Is Now World’s Largest Milk Producer,” India Perspectives, May 1999, pp. 25–26; A. Banerjee, “Dairying Systems in India,” World Animal Review, vol. 79, no. 2 (1994).
54. FAO, op. cit. note 10; U.N. Population Division, op. cit. note 3.
55. Dhall and Dhall, op. cit. note 53; Banerjee, op. cit. note 53; FAO, op. cit. note 10.
56. John Wade, Adam Branson, and Xiang Qing, China Grain and Feed Annual Report 2002 (Beijing: USDA, 2002); Gao Tengyun, “Treatment and Utilization of Crop Straw and Stover in China,” Livestock Research for Rural Development, February 2000.
57. USDA, ERS, “China’s Beef Economy: Production, Marketing, Consumption, and Foreign Trade,” International Agriculture and Trade Reports: China (Washington, DC: July 1998), p. 28.
58. FAO, op. cit. note 10; FAO, op. cit. note 41; U.N. Population Division, op. cit. note 3.
59. U.N. Population Division, op. cit. note 3; China’s economic growth from International Monetary Fund (IMF), World Economic Outlook Database, at www.imf.org/external/pubs/ft/weo, updated April 2009; FAO, FAOSTAT, electronic database at faostat.fao.org, updated 30 June 2007.
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