Prairies have very few trees, and only small hills. They may not get a lot of rain. Prairies are a type of temperate grassland, similar to savannahs or steppes. Temperate grasslands are cooler than those in the tropics, but warmer than those in polar areas.
Usually, when scientists talk about prairies, they are referring to the grasslands in North America. There, prairies stretch from the area east of the Rocky Mountains to the Mississippi River. Due to slow decomposition, the soil accumulates huge amounts of humus, whose black layer may be more than a meter thick hence the name of the soil: black earth, black land, chernozem. The little precipitation does not support trees, but grasses and herbs are present in great abundance.
Depending on the amount of rainfall, there are varieties of grasslands such as tallgrass, mixedgrass or shortgrass prairies and steppes.
In the latter, drought tolerant grasses such as feathergrass and buffalograss and annual plants predominate. Grasslands in North America are called prairie, in Eurasia they are called steppe in Hungary it is the puszta , and in South America pampa. Grasslands support a large number of herbivores from antelopes, horses and bisons to mice, groundsquirrels and gophers. The precipitation is unpredictable; there are long periods of drought lasting for eight to ten years.
Warm deserts experience very mild winters with few freezing days Sonoran, Chihuahuan, Saharan deserts , whereas cold deserts have an extended period of winter with termperatures well below freezing Taklimakan, Gobi. Plant cover is sparse, and characterized by drought tolerant brushes, succulent and annual plants. Deserts are particularly rich in reptiles snakes and lizards and rodents gerbils, jerboas and kangaroo rats , and most of the animals are nocturnal active at night.
The soil is very poor in nutrients, and the humus layer is absent or only weakly developed. There is mm of rain each year, with a pronounced wet or rainy, and an almost equally long dry season. Many are flat, but some occur on mountainsides. They also have very different species of plants and animals. Some grasslands in Nepal have grass species that reach up to 6 meters tall — almost twenty feet — while some United States grasslands have grasses less than a foot tall.
You won't find a rhinoceros and a black-footed ferret in the same place, even though they're both grassland animals. Rhinoceroses live in velds, while black-footed ferrets are prairie animals.
The brown color on the map above marks the areas across the world where grasslands are the main biome type. Click for more detail. The grassland biome is widespread around the world, and it's found at a wider range of latitudes our north-to-south measure of the earth than many other biomes, such as rainforests , deserts or tundra.
Grasslands are found on every continent, except Antarctica. They aren't found in the arctic either, where the climate is simply too extreme for grasses to thrive.
Depending on where grasslands are found, they can be either tropical, which means they stay about the same temperature year round, or temperate, which means they have hot summers and cold winters.
Forest and grassland often border each other. If the offspring of these trees spread into the grass and survive, then this whole area might become forest. If the trees die out, however, the grass will rapidly take over. Image by Patrick Mackie. If you look at a continent where both the forest and desert biomes are found, you'll often find that grasslands lie in between them. Not only that, but some of those deserts and forests were once, long ago, grasslands.
Areas where trees started to sprout on the grassland became forest. Areas where grass died out became desert. Stephanie Bittner. Fire keeps trees from growing on the prairie, but grasses and other prairie plants can survive fire and even thrive! There are three types of prairies: tall grass, mixed grass and short grass. Tall grass prairies get the most rain, about 30 inches a year. They have tall grasses, sunflowers and other plants. Grasses in this type of prairie can grow as high as five feet.
Tall grass prairies are found in the eastern part of the Midwest. Mixed grass prairies are found in the middle of the Midwest. They get less rain than tall grass prairies, between 15 and 20 inches a year, and the vegetation grows to about three feet tall. Short grass prairies get the least amount of rain, less than 10 inches a year.
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