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 5. Natural Systems Under Stress: Deteriorating Rangelands
One tenth of the earth’s land surface is cropland, but an area twice this size is rangeland—land that is too dry, too steeply sloping, or not fertile enough to sustain crop production. This area—one fifth of the earth’s land surface, most of it semiarid—supports the world’s 3.2 billion cattle, sheep, and goats. These livestock are ruminants, animals with complex digestive systems that enable them to digest roughage, converting it into beef, mutton, and milk. 35
An estimated 180 million people worldwide make their living as pastoralists tending cattle, sheep, and goats. Many countries in Africa depend heavily on their livestock economies for food and employment. The same is true for large populations in the Middle East, Central Asia, Mongolia, northwest China, and much of India. India, with the world’s largest cattle herd, depends on cattle not only for milk but also for draft power and fuel. 36
In other parts of the world, rangelands are exploited by large-scale commercial ranching. Australia, whose land mass is dominated by rangeland, has a flock of 95 million sheep, five times its human population. Grass-based livestock economies also predominate in Argentina, Brazil, Mexico, and Uruguay. And in the Great Plains of North America, semiarid lands that are not suited to growing wheat are devoted to grazing cattle. 37
Although public attention often focuses on the role of feedlots in beef production, the share of the world’s cattle in feedlots at any one time is a tiny fraction of the vast numbers feeding on grass. Even in the United States, which has most of the world’s feedlots, the typical steer is in a feedlot for only a matter of months.
Beef and mutton tend to dominate meat consumption where grazing land is abundant relative to population size. Among the leading beef consumers are the people of Argentina, Brazil, the United States, and Australia. Mutton looms large in diets in New Zealand and Kazakhstan. 38
These same ruminants that are uniquely efficient at converting roughage into food also supply leather and wool. The world’s leather goods and woolen industries, the livelihood of millions, depend on rangelands for raw materials.
Worldwide, almost half of all grasslands are lightly to moderately degraded and 5 percent are severely degraded. The problem is highly visible throughout Africa, the Middle East, Central Asia, and India, where livestock numbers track the growth in human numbers. In 1950, 238 million Africans relied on 273 million livestock. By 2004, there were 887 million people and 725 million livestock. Demands of the livestock industry, a cornerstone of the African economy virtually everywhere, often exceed grassland carrying capacity by half or more. 39
Iran—one of the Middle East’s most populous countries, with 70 million people—illustrates the pressures facing that region. With more than 9 million cattle and 80 million sheep and goats—the source of wool for its fabled rug-making industry—Iran’s rangelands are deteriorating from overstocking. In a country where sheep and goats outnumber humans, mutton consumption is widespread. With rangelands now pushed beyond their limits, however, the current livestock population is not sustainable. 40
China faces similarly difficult challenges. After the economic reforms in 1978 that shifted the responsibility for farming from state-organized production teams to farm families, the government lost control of livestock numbers. As a result, China’s cattle, sheep, and goat population spiraled upward. While the United States, a country with comparable grazing capacity, has 95 million cattle, China has 107 million. And while the United States has 7 million sheep and goats, China has 339 million. Concentrated in China’s western and northern provinces, sheep and goats are destroying the land’s protective vegetation. The wind then does the rest, removing the soil and converting productive rangeland into desert. 41
Fodder needs of livestock in nearly all developing countries now exceed the sustainable yield of rangelands and other forage resources. In India, the demand for fodder greatly outpaces the supply, leaving millions of emaciated, unproductive cattle. 42
Land degradation from overgrazing is taking a heavy economic toll in lost livestock productivity. In the early stages of overgrazing, the costs show up as lower land productivity. But as the process continues, it destroys vegetation, leading to erosion and the eventual creation of wasteland and desert. At some point, growth in the livestock population begins to shrink the biologically productive area and thus the earth’s capacity to sustain civilization. 43
35. Land area estimate from Stanley Wood, Kate Sebastian, and Sara J. Scherr, Pilot Analysis of Global Ecosystems: Agroecosystems (Washington, DC: International Food Policy Research Institute and WRI, 2000), p. 3; livestock counts from FAO, op. cit. note 10, updated 14 July 2005.
36. Number of pastoralists from “Investing in Pastoralism,” Agriculture Technology Notes (Rural Development Department, World Bank), March 1998, p. 1; FAO, op. cit. note 10, updated 14 July 2005.
37. FAO, op. cit. note 10, updated 14 July 2005; United Nations, op. cit. note 28.
38. USDA, Livestock and Poultry: World Markets and Trade (Washington, DC: USDA FAS, March 2000); population from United Nations, op. cit. note 28.
39. Robin P. White, Siobhan Murray, and Mark Rohweder, Pilot Analysis of Global Ecosystems: Grassland Ecosystems (Washington, DC: WRI, 2000); FAO, op. cit. note 10, updated 14 July 2005; United Nations, op. cit. note 28; Southern African Development Coordination Conference, SADCC Agriculture: Toward 2000 (Rome: FAO, 1984).
40. FAO, op. cit. note 10, updated 14 July 2005; United Nations, op. cit. note 28.
41. FAO, op. cit. note 10, with livestock data updated 14 July 2005.
42. B.S. Sathe, “Dairy/Milk Production,” in Livestock Investment Opportunities in India, FAO Web site, www.fao.org/DOCREP/ARTICLE/AGRIPPA/657_en00.htm, viewed 9 September 2005.
43. H. Dregne et al., “A New Assessment of the World Status of Desertification,” Desertification Control Bulletin, no. 20, 1991.
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