Tundra Biome By: Paula Cardenas

Characteristics Extreme cold climates Low biotic diversity Simple vegetation structure Limitation of drainage Short season of growth and reproduction Energy and nutrients in the form of dead organic material Large population oscillatations

Where it is found? The Arctic tundra lies between the North Pole and the taiga or the coniferous forests. In North America, it occurs in Greenland, Canada and Northern Alaska, in northern Europe, it is mainly found in Scandinavia, and in northern Asia, it is found in Siberia. The Antarctic tundra occurs on various Antarctic as well as sub-Antarctic islands, which include the Kerguelen Islands, the South Sandwich Islands, and South Georgia. The Alpine tundra can be found at very high elevations on frozen mountaintop regions. In North America, it occurs in Mexico, U.S.A., Canada, and Alaska. In South America, it is found in the Andes Mountains. In northern Europe, it is found in Sweden, Russia, Norway, and Finland. In Africa, it can be found in Mt. Kilimanjaro. And in Asia, it occurs in the Himalayan Mountains, which is located in Southern Asia, and in Mt. Fuji, in Japan.

What kind of animals live in Tundras? Even though there is not much biodiversity, with only about 48 species of land mammals occurring in the tundra biome, there are surprisingly large numbers of each species. The tundra animals mainly are slightly modified forms of deer, bears, foxes, wolves, rodents, hares, and shrews. In North America, there are large caribou herds, which are called reindeer in Eurasia, which feed on plants and lichens. Smaller musk-oxen herds also roam about the frozen regions. The predators of the tundra biome are polar bears, arctic foxes, and wolves. Some of the smaller mammals are lemmings and snowshoe rabbits. Although there are not too many types of insects to be found in the tundra, however, tiny midges that bite, mosquitoes, deer flies, and black flies do occur, which can make the summers in the tundra quite miserable. The mosquitoes that occur in the tundra prevent themselves from freezing by substituting the water in their bodies with glycerol, which acts like an anti-freeze. The marshy regions of the tundra are where migratory birds like plovers, sandpipers, and harlequin flock to in the summers. Due to it being isolated from other continents, the Antarctic tundra, in contrast with the Arctic tundra, is devoid of large mammal species. Sea birds and sea mammals, such as penguins and seals, however, do occur in areas close to the shore, while small mammals like cats and rabbits have been introduced by humans on some of the sub-Antarctic islands. As is evident, the Tundra Biome is not a useless and cold wasteland. In fact, its very nature makes the environment very fragile, and the animals and plants that have made the tundra their home have adapted themselves incredibly intricately to its short, although abundant, summers and cold, long winters. They exist on a precarious edge, hence, the most minor of stresses can lead to their destruction.

What kind of plants are found in tundras? Considering the extremely inhospitable conditions of the tundra biome, there are as many as 1,700 different plant species that grow here. The tundra plants consist mostly of mosses, grasses, lichens, sedges, and shrubs. About 400 types of flowers bloom in the growing season, which lasts just for 50-60 days. Except for a few birches in the lower altitudes, no trees grow in the tundra. Because of the permafrost, trees cannot send their roots into the ground. Although in some parts of the tundra willows do grow, but only up to about 8 cm, or 3 inches, high. Developing over thousands of years, most of the vegetation have adapted to the conditions in the tundra by growing in a dense mat of roots. Except where the soil is fertilized by animal droppings, the soil is low in minerals and nutrients. Being too dry and cold for vegetation to grow, the Antarctica tundra is mostly covered by large expanses of ice fields. However, in some parts of the region, especially the Antarctic Peninsula, there are areas where there is rocky soil which can support vegetation. The plant species that exist here are aquatic and terrestrial species of algae, which occur in the exposed soil and rock areas around the shore, liverworts, mosses, and lichens. The two flowering species of plants, the Antarctic pearlwort and Antarctic hair grass can be found in the western and northern parts of the Antarctic Peninsula.

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