(Environment & Ecology) Terrestrial Biomes - Tundra Biome, Arctic Tundra, Alpine Tundra Characteristic Features
Characteristic of tundra include:
- Extremely cold climate
- 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 oscillations
Although of uniform nature, but they have been divided in two parts:
The arctic tundra occupies earth’s Northern hemisphere, circling the North pole all the way down to the evergreen forests of the boreal biomes. The soil of the Arctic Tundra is poor in nutrients, which accounts for the low amount of vegetation. There is allowing little room for deep rooting plants and trees. The plants that do survive the frozen landscapes, are extremely resilient, and their roots are close to the surface of the arctic tundra’s plant life consists of shrubbery, lichen, moss, and flowers, Birds, of the tundra migrate south during the winter months, causing constant change in the animal population.
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, but the average summer temperature is 3-12°C, which enables this biome to sustain life.
Rainfall may vary in different regions of the arctic. Annual precipitation, including melting snow, is 15 to 25 cm.
All of the Plants are adapted to sweeping winds and disturbances of the soil. Plants are short and group together to resist the cold temperatures and are protected by the snow during the winter. They can carry out photosynthesis at low temperature and low light intensities. The growing seasons are short and most plants reproduce by budding and division rather than sexually by flowering.
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 from fat. Many animals hibernate during the winter, like birds do. Reptiles and amphibians are few or absent because of the extremely cold temperatures. Because of constant immigration and emigration, the population continually oscillates.
Soil is formed slowly, A layer of permanently frozen subsoil called permafrost exists, consisting mostly of gravel and finer material, when water saturates the upper surface, bogs and ponds may form, providing moisture for plants. 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.
The Alpine Tundra biome exists on rocky mountaintops and is very similar to the arctic Tundra except for a conspicuous lack of trees, Because trees cannot grow at this high altitude, most of the Alpine Tundra’s plant life consists of shrubbery and small leafy plants such as alpine bluegrass which is consumed by a variety of grazing animals such as bighorn sheep and mountain goats.
They are usually at an altitude of about 10,000 feet or more. The alpine biome lies just below the snow line of a mountain.
In the summer average temperatures range from 10° to 15°C. In the winter the temperature are below freezing. The winter season can last from October to May. The summer season may last from June to September. The temperatures in the Alpine biome can also change from warm to freezing in one day.
At high altitudes there is very little CO2 which plants need to carry on photosynthesis.
Because of the cold and wind, most plants are small perennial groundcover plants which grow and reproduce slowly, They protect themselves from the cold and wind by hugging the ground. Taller plants or trees would soon get blown over and freeze.
When plants die they don’t decompose very quickly because of the cold. This makes for poor soil conditions.
Most Alpine plants can grow in sandy and rocky soil, Plants have also adapted to the dry conditions of the alpine biome.
Alpine animals have to deal with two types of problems : the cold and too much high UV wavelengths. This is because there are fewer atmospheres to filter UV rays from the sun. There are only warm blooded animals in the Alpine biome, although them are insects .
Alpine animals adapt to the cold by hibernating, migrating to lower, warmer areas, or insulating their bodies with layers of fat, Animals will also tend to have shorter legs, tails, and ears, in order to reduce heat loss. Alpine animals also have larger lungs, more blood cells and hemoglobin because of the increase of pressure and lack of oxygen at higher altitudes. This is also true for people who have lived on mountains for a long time, like the Indians of the Andes Mountain is South America and the sherpas of the Himalayas in Asia.