Some grasses might be under 0. 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.
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The Rights Holder for media is the person or group credited. Tyson Brown, National Geographic Society. Perennial grasses, with their growth buds at or just below the surface, are well-adapted to drought, fire, and cold.
The tiller or narrow, upright stem reduces heat-gain in the hot summers; the intricate root systems trap moisture and nutrients. Two basic types are:. The Palouse Prairie of eastern Washington state, the California grasslands, and the desert grasslands of the Southwest are also temperate grasslands.
Eurasia : the steppes from Ukraine eastward through Russia and Mongolia. 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. 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. Skip to content. Joel Sartore.
In fact, grasslands often lie between forests and deserts. See grassland photos. They are generally open and fairly flat, and they exist on every continent except Antarctica, which makes them vulnerable to pressure from human populations. Threats to natural grasslands, as well as the wildlife that live on them, include farming, overgrazing , invasive species , illegal hunting , and climate change.
At the same time, grasslands could help mitigate climate change: One study found California's grasslands and rangelands could store more carbon than forests because they are less susceptible to wildfires and drought. Still, only a small percentage—less than 10 percent—of the world's grassland is protected.
There are two main kinds of grasslands: tropical and temperate. Examples of temperate grasslands include Eurasian steppes, North American prairies, and Argentine pampas. Tropical grasslands include the hot savannas of sub-Saharan Africa and northern Australia. Rainfall can vary across grasslands from season to season and year to year, ranging from 10 to 40 inches annually. Temperatures can go below freezing in temperate grasslands to above 90 degrees Fahrenheit.
The height of vegetation on grasslands varies with the amount of rainfall. Some grasses might be under a foot tall, while others can grow as high as seven feet.
Their roots can extend three to six feet deep into the soil. 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.
Grasslands support a variety of species.
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