The Tundra
In physical geography, tundra can be defined as a kind of biome in which cooler temperatures and short growing seasons lead to hindrance in the growth of trees.
Dwarf shrubs, mosses, sedges and grasses, and lichens are composed of tundra vegetation. In some regions of tundra, the growth of scattered trees is observed. The ecotone (or ecological boundary region) is referred to as the timberline or tree line and is present in between the tundra and the forest. Further, the tundra soil is found to be highly rich in phosphorus and nitrogen. There exist three regions and associated kinds of tundra, namely, Arctic tundra, alpine tundra, and Antarctic tundra.
Arctic Tundra
The Arctic tundra is found in the Arctic regions of the northern hemisphere, located north to the subarctic boreal forest. The term "tundra" commonly applies to the regions whereby permanently frozen soil or permafrost is the subsoil. (In general, it can also apply to the barren plain, wherein it might include northern Sapmi.) Permafrost tundra covers large areas of Canada and northern Russia. Many groups are mainly nomadic reindeer herders throughout the polar tundra, including the Nganasan and Nenets in the permafrost zone.
There are regions of solid landscape in the Arctic tundra where it is frozen for most of the year. From 25 to 90 cm (10 to 35 in) down there, the soil is frozen, making it difficult for trees to grow. Rather, only certain forms of Arctic vegetation, low-growing plants including the heath (varieties of Ericaceae including certain crowberry and black bearberry), moss, and lichen, can withstand bare and often rocky ground.
In the polar tundra zones, there have been two primary seasons, summer and winter. It is quite cold and dark throughout the winter, with a mean temperature at about -28° C (-18° F), often dipping as low as -50° C (-58° F). Severe winter temperatures on the tundra, however, do not fall as deep as those encountered further south in the taiga areas.
Temperature goes up somewhat during summers, and the upper layers of seasonally-frozen soil disappear due to melting. This leaves the earth very moist and soggy. During the warmer seasons, the tundra is covered in marshes, wetlands, bogs and streams. During the season of summers, daytime temperatures usually rise to approximately 12° C (54° F), but may sometimes drop to 3° C (37° F) or maybe even below zero.
Antarctic Tundra
Antarctic tundra is found to happen on the Antarctic as well as in the subantarctic islands. These islands may include South Georgia and the Kerguelen Islands and the South Sandwich Islands. Much of Antarctica is highly cold yet dry for supporting the vegetation. Moreover, the polar tundra covers much of the continent there.
Some parts of the globe, however, specifically the Antarctic Peninsula, carries the areas of rocky soil which is highly preferable and supportive for the life of plants. Actually, the flora comprises almost 25 liverworts, 100 mosses, 300-400 lichens, and approximately 700 species of aquatic and terrestrial algae that live in uncovered rock and soil regions along the continent's coast.
In the western and northern parts of the Antarctic Peninsula, Antarctica carries two different kinds of flowering plant plants, namely, the Antarctic pearl (Colobanthus quitensis) and the Antarctic hair grass (Deschampsia antarctica). The Antarctic tundra, in comparison to the Arctic tundra, lacks a large mammal fauna. And this is mainly because of the physical isolation from the other major continents.
Alpine Tundra
Since the weather and soils at higher elevations obstruct tree growth, alpine tundra does not carry trees. The alpine tundra's cold climate or snowy tundra is characterised by reduced temperatures throughout the air and is close to that of the polar climate. Alpine tundra is distinct from arctic tundra such that there is normally no permafrost seen in alpine tundra, however, alpine soils are usually better drained than arctic soils.
Stunted forests growing at the forest-tundra ecotone (the treeline) are recognized as Krummholz. Alpine tundra converts to subalpine forests below the tree line.
Alpine tundra tends to occur in mountains worldwide. The plants growing close to the ground, like sedges, perennial grasses, cushion plants, forbes, mosses, and lichens, define the flora of the alpine tundra.
The tundra forest or flora is suited to the alpine environment's harsh and unfavourable conditions, including dryness, snowy tundra, ultraviolet radiation and a limited growing season.
Fun Facts about Tundra World
In summer seasons, polar bears travel to the tundra to have their infants.
In tundra, Animals appear to have short ears and tails. In the cold, this allows them to drain little heat. They also appear to have big feet, so they can climb on top of the snow.
During the winter seasons, Lemmings, small mammals of the tundra world, burrow underneath the ice to eat grass and moss.
The term tundra comes from the word tunturi in Finnish, meaning treeless plain or barren ground.
FAQs on Tundra
1. What is the Tundra Biome, and what are its primary characteristics?
The Tundra biome is a vast, treeless region found in the coldest parts of the world, such as the Arctic and on top of high mountains. Its primary characteristics include:
- Permafrost: A permanently frozen layer of soil beneath the surface.
- Low Temperatures: Long, cold winters and short, cool summers.
- Short Growing Season: Ranging from just 50 to 60 days.
- Low-Growing Vegetation: Plants like dwarf shrubs, mosses, lichens, and grasses dominate.
- Limited Precipitation: Receives very little rainfall, similar to a desert.
2. What are the different types of Tundra and where are they located?
There are three main types of Tundra, distinguished by their geographic location:
- Arctic Tundra: Located in the northern hemisphere, encircling the North Pole and extending south to the coniferous forests of the taiga. It is found in regions like Northern Alaska, Canada, and Siberia.
- Alpine Tundra: Found on high-altitude mountaintops worldwide, above the treeline. It can be found in ranges like the Himalayas in Asia, the Alps in Europe, and the Rocky Mountains in North America.
- Antarctic Tundra: Located on the continent of Antarctica and its surrounding islands, such as the South Shetland Islands. It is the coldest and driest of the three.
3. What is permafrost, and what is its crucial role in the Tundra ecosystem?
Permafrost is a layer of soil, rock, or sediment that remains frozen for more than two consecutive years. In the Tundra, it plays a critical role by:
- Restricting Plant Growth: It prevents trees and plants with deep root systems from growing.
- Impeding Drainage: As an impermeable layer, it stops surface water from draining, leading to the formation of bogs and lakes in the summer.
- Storing Carbon: It traps vast amounts of carbon from dead organic matter. The thawing of permafrost due to climate change threatens to release this carbon as greenhouse gases.
4. How have animals adapted to survive the extreme conditions of the Tundra?
Animals in the Tundra have developed remarkable adaptations to survive the harsh environment. Key examples include:
- Insulation: Thick coats of fur (e.g., musk ox, arctic fox) or layers of blubber (e.g., seals) to protect against extreme cold.
- Camouflage: Many animals, like the arctic hare and ptarmigan, have white fur or feathers in winter to blend in with the snow.
- Migration and Hibernation: Many species, especially birds, migrate to warmer regions during the winter, while some mammals hibernate to conserve energy.
- Compact Body Size: Animals often have short legs and ears to minimize heat loss.
5. Why is the soil in the Tundra region often waterlogged during its short summer?
The soil in the Tundra becomes waterlogged in summer because of the underlying permafrost. When the top layer of soil, known as the 'active layer', thaws, the meltwater cannot drain downwards. The frozen permafrost acts as a barrier, trapping the water at the surface and creating swampy, marsh-like conditions.
6. Why do many Tundra plants have dark-coloured leaves or grow close to the ground?
These features are key survival adaptations. Dark-coloured leaves help the plants absorb more solar radiation, which provides warmth and aids photosynthesis in the cold, low-light environment. Growing in low, cushion-like forms helps plants stay out of the harsh, cold winds and trap pockets of warm air, protecting them from freezing.
7. How is global climate change affecting the Tundra biome?
Climate change is having a profound impact on the Tundra, one of the world's most sensitive ecosystems. Rising global temperatures are causing the permafrost to thaw, which leads to several critical issues: the release of potent greenhouse gases like methane and carbon dioxide, landscape instability, damage to infrastructure, and a shift in vegetation as shrubs and larger plants begin to colonise the warming soil.
