The word tundra refers to a “barren land” where the environmental conditions are so severe that life cannot sustain. Tundra can be of two types Alpine tundra and Arctic tundra.
Tundra Ecosystem Definition
The word tundra refers to a “barren land” where the environmental conditions are so severe that life cannot sustain. Tundra food chain can be of two types Alpine tundra and Arctic tundra.
Different Types of Tundra Ecosystem
Alpine Tundra Ecosystem
It is found to occur on the high mountain ranges of the world, on the peaks of the mountains at altitudes above the tree line. At such altitudes, there exists a permanent snow cover throughout the year. Alpine tundra is different from Arctic tundra. The former shows diurnal variations in temperature because the mountain ranges can be found at all latitudes, unlike the latter which is only found in polar latitudes. All the major mountain ranges of the world such as the Himalayas, the Alps, the Rockies, the Andes etc., have the alpine tundra.
Characteristics of Alpine Tundra
The Alpine is comparable to arctic tundra in that it lacks trees, has relatively low yearly temperatures, and most species move to these areas only during the productive summer months. The alpine tundra, on the other hand, receives more precipitation and has warmer annual average temperatures than the arctic tundra. The Alpine tundra food chain is significant due to its biodiversity; it can be used to establish undisturbed monitoring stations, as well as for recreational and leisure activities and mineral wealth generation.
Arctic tundra Ecosystem
It occurs as a continuous belt south of the polar ice caps and north of the tree line in the northern hemisphere. It is found in Russia (in Siberia), Canada, USA (in Alaska) and in a few islands of the Arctic Ocean. In the southern hemisphere, tundra is mostly absent. It is found only in a few areas of South America close to the south pole. This is because there is little landmass in the southern hemisphere close to polar latitudes and most of the area is covered by the Southern Ocean. Since it is found in polar latitudes, the diurnal variations in temperature are very low.
Characteristics of Arctic Tundra
The region has a very low mean annual temperature. In winters, the temperatures drop to as low as 50 degrees Celsius below the freezing point, especially in the Arctic tundra of the continental interiors such as Siberia.
Most of the precipitation occurs during winters in the form of snow and sleet. Extreme snow storms, also known as blizzards, can occur during winters which lead to heavy snowfall.
Since the ground (soil) remains frozen for most of the time in a year, trees cannot grow in this region. The only vegetation that is found here includes mosses, lichens, cotton grass, dwarf heath, sedges, willows, and birches.
Hardy grasses and reindeer moss are found to occur close to coastal lowlands which are the only pastures which support the population of reindeers in the Arctic tundra.
The brief summer period in Arctic tundra supports the growth of berry-bearing bushes and flowers. Several insects are found to survive on these flowers and berries. These insects have a very short lifespan, coinciding with thaw season. Birds are attracted to the north in summers because of this insect population.
The prominent wildlife which is found in the Arctic tundra includes the polar bear, arctic willow, musk ox, arctic hare, arctic fox, reindeer, wolf, lemming etc. The animals found in this region have a long lifespan. E.g., Arctic Willow, also known as Salix Arctica, can survive for 150 to 300 years.
These animals have a thick cuticle and epidermal hair which protects them from the chilly weather of the region. Mammals which are found in this region have a large body size and small tail and ear in order to prevent the loss of heat from their bodies. Most of the animals have fur-covered bodies which act as an insulator.