ABSTRACT
Williams et al. (1968) indicated that about one-third of the Earth is land area, or 14 billion hectares (ha). Approximately 10% is farmed, 28% is in forest (which is grazed at least part-time), and 15% is covered with icecaps or fresh water, leaving 47% or nearly half of the globe for grazing by livestock or game animals. Such land is usually only suitable for grazing because it is too steep, shallow, sandy, and wet, cold, or saline for crops. Williams et al. (1968) indicated that 75% of the domestic animals and most wildlife depend upon grazing lands for survival. Such land is also extremely important as watersheds, for conservation, for wood, medicinal, and industrial compounds, for mining resources, and for recreational purposes. Forests and grasslands are also apparently more efficient in carbon dioxide removal from the atmosphere than cropland, which according to some investigators may be increasing to the point of causing unacceptable climatic change unless reversed (Woodwell, 1978; Mayeux et al., 1991).
