Grasslands cover one fourth of the Earth's land and are found on every continent, except for Antarctica. Grasslands occur where it is too wet for deserts but too dry for forests. Grasslands get about 10 to 24 inches of precipitation per year, although some tropical grasslands can get over 40 inches of rain a year. Tropical grasslands are close to the equator and are hot all year long. The grasslands in Africa are called savannas or veldts and are home to animals like zebras, lions and ostriches.
Temperate grasslands are hot in the summer and cold in the winter. In Europe and Asia, temperate grasslands are called steppes. In South America grasslands are called pampas. In North America temperate grasslands are called prairies. Their roots can extend 0. The combination of underground biomass with moderate rainfall—heavy rain can wash away nutrients—tends to make grassland soils very fertile and appealing for agricultural use.
Much of the North American prairielands have been converted into land for crops, posing threats to species that depend on those habitats, as well as drinking water sources for people who live nearby.
Grassland Plants and Animals Grasslands support a variety of species. Vegetation on the African savannas, for example, feeds animals including zebras, wildebeest, gazelles, and giraffes.
On temperate grasslands, you might find prairie dogs, badgers, coyotes, swift foxes, and a variety of birds. There can be up to 25 species of large plant-eaters in a given grassland habitat, comprising a sort of buffet where different grasses appeal to different species.
Some grass species in these habitats include red oat grass Themeda triandra and Rhodes grass Chloris gayana in tropical savannas, and purple needlegrass Nassella pulchra and galleta in temperate areas.
When rainy season arrives, many grasslands become coated with wildflowers such as yarrow Achiella millefolium , hyssop, and milkweed. The plants on grasslands have adapted to the drought, fires, and grazing common to that habitat. Fires, both natural and human-caused, are important factors shaping grasslands.
In the U. Midwest, for example, Native Americans set fires to help maintain grasslands for game species, such as bison. Fire can also help prevent fire-intolerant trees and shrubs from taking over while increasing the diversity of wildflowers that support pollinators. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
The Rights Holder for media is the person or group credited. Tyson Brown, National Geographic Society. For information on user permissions, please read our Terms of Service. South America : the pampas of Argentina, Uruguay, and southeastern Brazil. Africa : the veld in the Republic of South Africa. Soils: Calcification is the dominant soil-forming process in semiarid regions.
Mild leaching, high organic content, and concentration of calcium carbonate in the B horizon typifies the dark brown mollisols developed under the temperate grasslands. Loess and hence chernozem underlie the eastern prairies of the US, the pampas of South America, and the steppes of Ukraine and Russia.
Fauna: The temperate grassland fauna is very low in diversity, especially in comparison with the tropical grasslands or savannas of Africa. In North America the dominant herbivores are bison Bison bison and pronghorn the sole member of the Nearctic endemic family, Antilocapridae.
Rodent herbivores include the pocket gopher another Nearctic endemic , ground squirrels, and the prairie dog. Text on this page is printable and can be used according to our Terms of Service.
Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. Extinction is the complete disappearance of a species from Earth. Species go extinct every year, but historically the average rate of extinction has been very slow with a few exceptions. The fossil record reveals five uniquely large mass extinction events during which significant events such as asteroid strikes and volcanic eruptions caused widespread extinctions over relatively short periods of time.
Some scientists think we might have entered our sixth mass extinction event driven largely by human activity. Our planet is dependent on an interconnected system.
If we lose one species, how does that impact the whole system? What if we lose hundreds? Help your students understand the gravity of extinction with these classroom resources. Savanna, steppe, prairie, or pampas: They're all grasslands, the globe's most agriculturally useful habitats. A biome is a large community of vegetation and wildlife adapted to a specific climate. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
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