Grassland Biome,Microsoft® Encarta® Encyclopedia 99. © 1993-1998
Grasslands, as the name implies, are dominated by grasses. Grassland biomes form an ecological zone lying between deserts and temperate forests, and generally lie in the interior of continents. With this worldwide distribution, grasslands have many names, including the prairies and plains of North America, the pampas and paramos of South America, the veld of South Africa, and the steppes of Eurasia.
Being located between dessert and forest, grasslands generally receive more rainfall than deserts, but less than forest. Grasslands average between 250 and 750 mm (10 and 30 in) of rainfall per year.
Grasslands can support 50 or more species, but 60% of the biomass is made of only two or three species. Native grasslands can support a vastly diverse fauna. The North America grasslands once held large grazing herbivores such as the bison, coyotes and wolves, prairie dogs and mice; seed-eating birds; hawks; snakes; and insects, and especially grasshoppers.
Opposite from what many would believe, grasslands' low rainfall contribute to the high nutrients in the soil. With more rain, the nutrients would wash away, as we have seen in recent decades with the poor farming techniques and development leading to high soil erosion in the grasslands and Europe and North America.