Where is the Tundra Located?The tundra is located at the top of the world, near the North Pole. This enormous biome, extremely uniform in appearance, covers a fifth of the earths surfaceThe most distinctive characteristic of tundra soil is its permafrost, a permanently frozen layer of ground. During the brief summers, the top section of thesoil may thaw out allowing plants and microorganisms to grow and reproduce. However, these plants and microorganisms become dormant during thecold winter months.There is another region called alpine tundra, which is found on the tops of tall, cold mountains. The word tundra derives from the Finnish word for barrenor treeless land. The tundra is the simplest biome in terms of species composition and food chains. * low precipitation (less than five inches/year)coupled with strong, drying winds. Snowfall is actually advantageous to plant and animal life as it provides an insulating layer on the ground surface.Soil: No true soil is developed in this biome due to the edaphic factors mentioned above.Fauna: Strategies evolved to withstand the harsh conditions of the tundra can be divided among those species that are resident and those that aremigratory.* Among the small number of bird (e.g., ptarmigan) and mammal (e.g., muskox, arctic hare, arctic fox, musk ox) species that reside year-round on thetundra one commonly finds: Morphological adaptations* large, compact bodies following Bergmanns and Allens rules * a thick insulating cover of feathers or fur * pelage and plumage that turns white inwinter, brown in summer Physiological adaptations* ability to accumulate thick deposits of fat during the short growing season. Fat acts as insulation and as a store of energy for use during the winter,when animal species remain active. Population adaptations* cyclical fluctuations in population size, best seen perhaps in the lemming, a small rodent which is the major herbivore in the tundras simple food chain.Predator populations and plant populations respond in kind to the peaks and crashes of the herbivore populations.* Migratory species such as waterfowl, shorebirds and caribou adapt to the tundra by avoiding the most severe conditions of winter. Each year at theend of the short growing season they move southward into the boreal forest or beyond, but return to the tundra to breed.Aperiodic emigration from the tundra is exhibited by the snowy owl during those years that the lemming populations have crashed. Those winters seesnowy owl irruptions as far south as Virginia. Most owls are found with empty stomachs and do not survive to return to the Arctic.Distribution: The tundra biome is restricted to the high latitudes of the northern hemisphere in a belt around the Arctic Ocean. Many of its species, bothplant and animal, have circumpolar distribution areas.Within the tundra biome a latitudinal zonation of communities is realized:* High Arctic Tundra: essentially confined to the islands of the Arctic Ocean and characterized by scattered lichens and mosses on care rock surfacesand perennial forbs growing in protected crannies among sharp, ice-fractured rock debris.* Middle Arctic Tundra: restricted to the Arctic Coastal plain where level terrain, a thin active layer, and freeze and thaw result in or rock polygons. Thesorting of particles by freeze-thaw activity results in a waterlogged center to the polygons, a microhabitat conducive to sphagnum moss and sedges; andan outer ring that is drier and provides a microhabitat favorable to forbs and some dwarf heaths.* Low Arctic Tundra: the majority of the tundra lies on better drained slopes with greater depth to permafrost than is encountered on the Arctic coastalplain. Here there is a greater frequency of woody shrubs: willow, birch, and various berry-bearing members of the heath family. Along streams willowsand alders may be 10 feet high. On south-facing slopes needleleaf evergreen trees (spruce and fir) are established and represent the northernmostextensions of the great boreal forest to the south. (Such areas where two biomes interdigitate are known as.)
Tundra Facts: Arctic TundraThe Arctic Tundra region is situated near the North Pole. The soil in the area is called permafrost which means permanently frozen soil. Atleast 25 to 90 centimeters of the ground is frozen. Thus it is impossible for trees to grow here. Due to this, vegetation is very hard to growand very sparse to find. Moss, lichen and heath can be found on rocks in this barren landscape.The people who live in the Arctic Tundra are mostly nomadic tribes consisting of reindeer hunters such as the Nenets and the Nganasan.The Tundra climate consists of only two seasons: winter and summer. The region is frozen for the most part of the year. The averagetemperatures range from -28 Degrees Celsius (-18.4 Degrees Fahrenheit) to -50 Degrees Celsius (-58 Degrees Fahrenheit). During thesummers the ice melts and forms streams, lakes, marshes and bogs. This makes the ground quite soggy. The temperatures during summermonths range from 12 Degrees Celsius (53.6 Degrees Fahrenheit) to 3 Degrees Celsius (37.4 Degrees Fahrenheit). There is some amountof precipitation, but only in the summer months, ranging from 15 to 25 centimeters annually.It is during these summer months, that plants grow and reproduce.The interesting part about the Tundra Climate is that it is quite windy, with winds that blow upwards of 30 to 60 miles per hour.Another interesting fact about the Tundra region is that in the summer months when the ice begins to melt, it cannot be absorbed into theground. This is because only the upper layers of the permafrost melt, while the bottom layers are still frozen.The tundra ecosystem is also very low in biodiversity. There are only about 1700 varieties of plants and about 48 varieties of land mammalsfound in the tundra region. The main animal population in the Arctic Tundra consists of reindeer, polar bears, arctic fox, arctic hare, snowyowls, lemmings and musk ox.It is interesting to note that the Tundra region is also a vast storehouse of natural resources such as oil and uranium. It is because of thesenatural resources that many nations have turned their attention to these areas on the globe.
Tundra Facts: Antarctic TundraThe Antarctic Tundra is found in the South Polar areas of theEarth. However this area is quite cold and does not supportvegetation. It is always covered with ice fields.However, at the fringes of the Antarctic Peninsula, there areareas of rocky soil which do support vegetation. One can findabout 300 varieties of lichens, 700 varieties of aquatic algae, andabout 100 varieties of mosses. There are not many large sizedmammals found in the Antarctic Tundra. This area is the home ofspecies such as the Penguins and Seals.
Tundra Ecosystem: ThreatsAs mentioned above, the Arctic Tundra is a vast reservoir of oil anduranium. Due to this many countries are exploring for oil in theseregions. This can severely damage the delicate balance of the tundraecosystem.Another threat is that about a third of the worlds soil bound carbon isfound in these regions. So when the permafrost melts in the summers,this carbon gets released into the atmosphere, adding to theGreenhouse Effect. Since carbon is a greenhouse gas, this adds intothe threat of Global Warming, which again forms a vicious cycle bycausing more of the permafrost to melt each year.Over a period of time, this could radically alter the lives of the livingspecies of animals, but also flora and fauna, and subsequently the livesof all the people on the surface of the earth.Many scientists and researchers are therefore spending a lot of timeand effort into trying to analyze and reduce this growing threat to thetundra ecosystem.By Madhavi Ghare
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