http://www.blueplanetbiomes.org/world_biomes.htm
What is a Biome?
A biome is a large geographical area of distinctive plant and animal groups, which are adapted to that particular environment. The climate and geography of a region determines what type of biome can exist in that region. Major biomes include deserts, forests, grasslands, tundra, and several types of aquatic environments. Each biome consists of many ecosystems whose communities have adapted to the small differences in climate and the environment inside the biome.
All living things are closely related to their environment. Any change in one part of an environment, like an increase or decrease of a species of animal or plant, causes a ripple effect of change in through other parts of the environment.
The earth includes a huge variety of living things, from complex plants and animals to very simple, one-celled organisms. But large or small, simple or complex, no organism lives alone. Each depends in some way on other living and nonliving things in its surroundings.
Ecological Relationships of Biomes
The survival and well being of a biome and its organisms depends on ecological relationships throughout the world. Even changes in distant parts of the world and its atmosphere affect our environment and us. The eruption of a volcano in Mexico, or Southeast Asia can bring the temperature of the whole world down a few degrees for several years.
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Grassland biomes are large, rolling terrains of grasses, flowers and herbs. Latitude, soil and local climates for the most part determine what kinds of plants grow in a particular grassland. A grassland is a region where the average annual precipitation is great enough to support grasses, and in some areas a few trees. The precipitation is so eratic that drought and fire prevent large forests from growing. Grasses can survive fires because they grow from the bottom instead of the top. Their stems can grow again after being burned off. The soil of most grasslands is also too thin and dry for trees to survive.
When the settlers of the United States moved westward, they found that the grasslands, or prairies as they called them, were more than just dry, flat areas. The prairies contained more than 80 species of animals and 300 species of birds, and hundreds of species of plants.
There are two different types of grasslands; tall-grass, which are humid and very wet, and short-grass, which are dry, with hotter summers and colder winters than the tall-grass prairie. The settlers found both on their journey west. When they crossed the Mississippi River they came into some very tall grass, some as high as 11 feet. Here it rained quite often and it was very humid. As they traveled further west and approached the Rocky Mountains, the grass became shorter. There was less rain in the summer and the winters got colder. These were the short-grass prairies.
Grassland biomes can be found in the middle latitudes, in the interiors of continents. They can have either moist continental climates or dry subtropical climates. In Argentina, South America, the grasslands are known as pampas. The climate there is humid and moist. Grasslands in the southern hemisphere tend to get more precipitation than those in the northern hemisphere, and the grass tends to be the tall-grass variety.
There is a large area of grassland that stretch from the Ukraine of Russia all the way to Siberia. This is a very cold and dry climate because there is no nearby ocean to get moisture from. Winds from the arctic aren’t blocked by any mountains either. These are known as the Russian and Asian steppes.
In the winter, grassland temperatures can be as low as -40° F, and in the summer it can be as high 70° F. There are two real seasons: a growing season and a dormant season. The growing season is when there is no frost and plants can grow (which lasts from 100 to 175 days). During the dormant (not growing) season nothing can grow because its too cold.
In tropical and subtropical grasslands the length of the growing season is determined by how long the rainy season lasts. But in the temperate grasslands the length of the growing season is determined by temperature. Plants usually start growing when the daily temperature reached about 50° F.
In temperate grasslands the average rainfall per year ranges from 10-30 inches. In tropical and sub-tropical grasslands the average rainfall per year ranges from 25-60 inches per year The amount of rainfall is very important in determining which areas are grasslands because it’s hard for trees to compete with grasses in places where the uppers layers of soil are moist during part of the year but where deeper layer of soil are always dry.
The most common types of plant life on the North American prairie are Buffalo Grass, Sunflower, Crazy Weed, Asters, Blazing Stars, Coneflowers, Goldenrods, Clover, and Wild Indigos.
Some common animals in the grasslands are Coyotes, Eagles, Bobcats, the Gray Wolf, Wild Turkey, Fly Catcher, Canadian Geese, Crickets, Dung Beetle, Bison, and Prairie Chicken.
by Sam M. 2000
Grassland Climate:
There are many types of grasslands around the world. Some of the grasslands are tropical and some are dry grasslands. Grasslands in North America are known as Prairies, and in South America they are known as the Pampas. Eurasia has the Steppes, and in South Africa they are called Savanna and Veldt.
The prairies of the midwestern United States are both tall-grass and short-grass. West of the Mississippi River the temperature is moist and humid. This allows for some very tall grasses of up to 10 feet. Summers are warm and humid. Winters are cold but not to the extreme. The farther west and in the interior of the country, the temperatures becomes drier. Moisture from the Pacific Ocean is blocked by the mountains. This is where the short-grass prairies are found. Summers are hot and winters very cold. There are no natural barriers, like trees, so there is a constant wind. Grasses with deep root systems keep the soil from blowing away. Most animals have adapted to the open, treeless prairie by digging burrows. Even owls, like the Burrowing Owl, use the holes dug by prairie dogs as nesting sites. The mean temperatures for the prairie in January is 20° F, and 70° F in July. Annual precipitation is 10-30 inches.
The Savanna is a tropical grassland in Africa. This grassland has a very hot, wet season when warm, moist air from the equator moves in. This is followed by a cooler dry season that can last for 8 months or more. Hot, dry air moves in from the Sahara. It is cooler by a few degrees Celsius because there is no moisture to trap the sun’s radiant energy, and most of the heat escapes into space again. The Veldt is in South Africa and is pretty much like a savanna, except in the southern hemisphere.
Another southern hemisphere grassland is the Pampas of Argentina. Moist, tropical air dominates this area and there is a lot of rain. Here tall-grass varieties of grasses grow very well.
The Steppes have a cold, dry climate. Here you find short-grass type of plants. The Himalayas block warm, moist air from the Indian Ocean, so there is very little precipitation. Nothing blocks arctic winds though, so winters are very cold and windy.
The grassland biome climate is in a mid-latitude zone. It is classified as a type “B” category, with a “Bs” subtype climate under the Köppen classification system. The grasslands have a very large latitude range, spanning from 55° N to 30° S. This is because of the many different types of grasslands throughout the world. The grasslands are on every continent, except for Antarctica.
by Emma K. 2000.
For more information on the Steppes of Eurasia, the North American Prairie, the Pampas and plant and animal life of this biome visit,
