Grasslands

By: Robert, Shane, Eleni, Colleen and Charlie

Climate and Soil

Climate

• The temperature of a grassland biome ranges from -40˚F (-40˚C) in the winter to 100˚F (38˚C).

• Most precipitation takes place between spring and summer.

• The annual precipitation rate ranges between 50.8-88.9 cm (20-35 in.)

Soil

• The soil type is clay, and its upper layers are fertile.

• The soil is held together by decomposed roots.• Grazing and trampling in the grasslands can

cause increased erosion of the soil.

Vegetation

Overview

• Although there are several different types of grasslands, they are all very similar and tend to vary only in plant species and temperature (overall types of plants present as well as plant adaptations are practically the same)

Temperate Grasslands• Temperate grasslands:

– Few trees or large shrubs– Mostly grasses, as the name would suggest– Two types of temperate grasslands – prairies and steppes; prairies have

tall grasses while steppes are filled with short grasses. – Most plants in the temperate grasslands are resistant to drought, fire

and grazing. The grasses manage to survive all of these because their leaves grow from the base, which is away from fires and animals that would destroy it. During a prairie fire, the leaves of the grass that are above ground are destroyed, but the base underground is protected by the soil above it.

– Because the grasses are wind-pollinated, they are easily able to spread in the open environment, allowing them to quickly cover the grasslands.

Temperate Grasslands

Prairie• Prairie:

– Trees such as cottonwoods, oaks and willows grow in river valleys.– There are a few hundred species of flowers– The amount of vegetation is maintained by grazing animals and

wildfires. This ensures that the grassland’s vegetation doesn’t become too thick and therefore helps other plants to grow.

Prairie

Steppe

• Steppe:–Plants include blue grama,  buffalo grass,

cacti, sagebrush, speargrass, and small relatives of the sunflower

Steppe

Tropical Grasslands• Tropical Grasslands (Savannas)

– Again, full of grasses– May have some trees, usually drought or fire resistant– Might have an open shrub layer– The grasses survive in the savanna because they are capable of growing quickly during

the rainy season, then turning brown and storing water and nutrients in their roots during the dry season.

– Plants have adapted to fires to the point where fires actually stimulate new growth in plants.

– Of all the plants in the savanna, the acacia tree has adapted the most. Its long roots ensure that it can access deep reservoirs of groundwater, ensuring that it can survive most droughts. The tree has also adapted to resist fires. It can keep growing from the root crown even after being burned. The tree is protected by sharp thorns and by a symbiotic relationship with ants. When an animal eats the leaves, the ants begin defending their tree, often driving away any animal that may try to graze on the acacia tree.

Tropical Grasslands

Animal Life

Prairie

• Grazing animals such as oxen and bison who fed on the prairie grass were also exploited by humans so bison being driven to near extinction by hunters.

• Animals like buffalo, horses, kangaroos, elephants and giraffes are all animals that also inhabit the prairie.

• Some of these animals were in danger of extinction despite their massive numbers.

Bison

Kangaroo

Giraffe

Steppe

• Animal life on the steppe is comprised of grazing mammals such as the antelope, and a wide variety of burrowing mammals such as ground squirrels and ferrets.

Antelope

Squirrel

Savanna• Several species of animals including birds, mammals, reptiles,

and insects congregate and feed upon the trees and grass or each other. 

• Humans have exploited many of the animals of the savanna biome, either for sport, fur, or illegal poaching. 

• Animals (which do not all occur in the same savanna) include elephants, giraffes, zebras, buffaloes, kangaroos, mice, moles, gophers, ground squirrels, snakes, worms, termites, beetles, lions, leopards, hyenas, and elephants.

• If there are large herbivores present, there will also be some carnivores following them.

Tiger

Elephant

Zebra

Human Factors

People on the Grasslands

• Prairie– Has fertile soil that is used for farming crops.– Prairie plants can yield 51%more energy per acre

then ethanol from corn for bio fuels.• Plants include lupine, big bluestem(turkey foot), blazing

star, switchgrass, and prairie grass.

People on the Grasslands

• Masai people– Live on the savannas in Kenya and Tanzania– Use grass, twigs, mud to build huts– Raise Cattle and livestock for survival

Masai People

Challenges on the Prairie

• The temperature can range from -40 degrees Fahrenheit to 70 degrees Fahrenheit

• Have a dormant season• Fires both natural and man made are common

Works Cited

• "Grasslands -- National Geographic." Environment Facts, Environment Science, Global Warming, Natural Disasters,

Ecosystems, Green Living - National Geographic. Web. 15 Nov. 2011.

<http://environment.nationalgeographic.com/environment/habitats/grassland-profile/>.

• Hagerty, Ryan. "Grasslands Habitat." Grasslands Habitat Facts - Defenders of Wildlife. Defenders of Wildlife, 2011.

Web. 13 Nov 2011.

• Living In The Environment: An Introduction To Environmental Science G. Tyler Miller--20th edition; Wadsworth

Publishing, Belmont, California,Encyclopedia Britannica, 20th Edition

• M., Sam. "Grasslands." Grasslands Biome. Blue Planet Biomes, 2000. Web. 14 Nov 2011.

• "Tropical Savannas."http://www.radford.edu. N.p., 2005. Web. 14 Nov 2011.

• Webber, Charles. "The grassland biome."http://www.ucmp.berkeley.edu. University of California Museum of

Paleontology, 2002. Web. 13 Nov 2011.