Tundra: The Not-So Barren Land
A picture of tundra

Tundra is the coldest of all the biomes. Tundra comes from the Finnish word tunturia, meaning treeless plain. It is noted for their frost-molded landscapes, extremely low temperatures, little precipitation, poor nutrients, and short growing seasons. Dead organic material functions as a nutrient pool. The two major nutrients are nitrogen and phosphorous. Nitrogen is created by biological fixation, and phosphorous is created by precipitation. Tundra are separated into two types: arctic tundra and alpine tundra.

Characteristic of Tundra

  1. Extremely cold climate
  2. Low biotic diversity
  3. Simple vegetation structure
  4. Limitation of drainage
  5. Short season of growth and reproduction
  6. Energy and nutrients in forms of dead organic material
  7. Large population oscillations

Arctic

Arctic tundra is located in the northern hemisphere that encircles the north pole and extends to south of the coniferous forests of the taiga. The arctic is known for its cold, desert-like conditions. The growing season ranges from 50 to 60 days. The average winter temperature is -34 C (-30 F), but the average summer temperature is 3 to 12 C (37 to 54 F), which enables this biome to sustain life. Rainfall is limited in different regions of the arctic. Yearly precipitation, including melting snow, is 15 to 25 cm (6 to 10 inches). Soil is formed slowly. A layer of frozen subsoil called permafrost is formed on the ground. It consists mostly of gravel and finer material. When water is saturated at the upper surface, it gathers at the top to form bogs and ponds to make up for the low precipitation and to provide moisture for plants. As a result, there are no deep root systems in the vegetation of the arctic tundra. However, there are still a wide variety of plants that are able to resist the cold climate. There are 1,700 kinds of plants in the arctic and subarctic, and these include:

All of the plants are adapted to sweeping winds and disturbances of the soil. Plants are short and group together to resist the cold temperature. They can carry out photosynthesis at low temperatures and low light intensities. They are protected by the snow during the winter. The growing seasons are short, and most plants reproduce by budding and division rather than sexually by flowering. The fauna in the arctic is also diverse:

Animals are adapted to handle long cold winters and to breed and raise young quickly in the summer. Animals such as mammals and birds also have additional insulation such as fat. Many animals hibernate during the winter because food is not abundant. Another alternative is to migrate south in the winter, like birds do. Reptiles and amphibians are few or absent because of the extremely cold temperature. Because of constant immigration and emigration, the population continually oscillates.

Alpine

Alpine tundra is located on mountains throughout the world at high altitude where trees cannot grow. The growing season is approximately 180 days. The nighttime temperature is usually below freezing. Unlike the arctic tundra, the soil in the alpine is well drained. The plants are very similar to those of the arctic ones and include:

Animals living in the alpine are also well adapted:


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