5.5.1. Current Status of Key Goods and Services
Estimates for rangeland cover vary between 31 and 51% of the land surface of
the Earth (Allen-Diaz, 1996; WRI, 2000); the upper estimate includes tundra
grasslands. Rangelands support human populations at low densities (Batchelor
et al., 1994) on almost every populated continent. The latest figures suggest
a population of at least 938 million peopleor about 17% of the world's
population (WRI, 2000).
The World Resources Institute report (WRI, 2000) assesses the food/fiber production
and biodiversity of rangelands as "fair" (on a scale of excellent,
good, fair, poor, and bad) over the past 20-30 years, but the underlying
biological ability of the rangelands to continue to support that productivity
and biodiversity is declining, suggesting that productivity and the biodiversity
assessment may not hold in the future. Livestock production in rangelands is
estimated to be 65 Mt in 1998 (WRI, 2000), with global meat production estimated
at 225 Mt. Nineteen percent of the world's centers for plant diversity
are found in rangelands. For carbon stores, the WRI assessment of rangelands
is "good"; again, however, the underlying ability is judged to be
declining (WRI, 2000). IPCC (2000) estimates carbon stores in rangelands as
84 Gt C in vegetation (of a global total of 466 Gt), 750 Gt C in soils (of a
global total of 2,011 Gt). WRI (2000) gives a range of 405-806 Gt for total
carbon stores. Both estimates suggest that rangelands are important carbon stores.
Many of the people in rangelands rely on fuelwood for their daily cooking and
heating needs. Estimated fuelwood use as a percentage of total energy use in
1993 for countries dominated by rangelands is about 60-90% (e.g., in Afghanistan,
Mozambique, Swaziland); the world average is 6%, and Africa's average is
35% (WRI, 1998).
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