Geographical location of tundra
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In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands", "treeless mountain tract". There are three types of tundra: Arctic tundra, alpine tundra, and Antarctic tundra. In tundra, the vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens. Scattered trees grow in some tundra. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline.
Arctic tundra occurs in the far Northern Hemisphere, north of the taiga belt. The word "tundra" usually refers only to the areas where the subsoil is permafrost, or permanently frozen soil. (It may also refer to the treeless plain in general, so that northern Sápmi would be included.) Permafrost tundra includes vast areas of northernRussia and Canada. The polar tundra is home to several peoples who are mostly nomadic reindeer herders, such as the Nganasan and Nenets in the permafrost area.
Arctic tundra occurs in the far Northern Hemisphere, north of the taiga belt. The word "tundra" usually refers only to the areas where the subsoil is permafrost, or permanently frozen soil. (It may also refer to the treeless plain in general, so that northern Sápmi would be included.) Permafrost tundra includes vast areas of northernRussia and Canada. The polar tundra is home to several peoples who are mostly nomadic reindeer herders, such as the Nganasan and Nenets in the permafrost area.
Abiotic features
- Plants like Heaths and mosses have to adapt to the very long and cold winters because the sun does not come up in the winter
- Wildlife like arctic tundra animals include snowy owls, reindeer, polar bears, white foxes, lemmings, arctic hares, wolverines, caribou, migrating birds, mosquitoes, and black flies.
Antarctic tundra occurs on Antarctica and on several Antarctic and subantarctic islands, including South Georgia and the South Sandwich Islands and the Kerguelen Islands. Most of Antarctica is too cold and dry to support vegetation, and most of the continent is covered by ice fields. However, some portions of the continent, particularly the Antarctic Peninsula, have areas of rocky soil that support plant life. The flora presently consists of around 300–400 lichens, 100 mosses, 25liverworts, and around 700 terrestrial and aquatic algae species, which live on the areas of exposed rock and soil around the shore of the continent. Antarctica's two flowering plant species, the Antarctic hair grass (Deschampsia antarctica) and Antarctic pearlwort (Colobanthus quitensis), are found on the northern and western parts of the Antarctic Peninsula.
In contrast with the Arctic tundra, the Antarctic tundra lacks a large mammal fauna, mostly due to its physical isolation from the other continents. Sea mammals and sea birds, including seals and penguins, inhabit areas near the shore, and some small mammals, like rabbit and cats, have been introduced by humans to some of the subantarctic islands. The Antipodes Subantarctic Islands tundra ecoregion includes the Bounty Islands, Auckland Islands, Antipodes Islands, the Campbell Island group, and Macquarie Island. Species endemic to this ecoregion include Nematocerasdienemum and Nematoceras sulcatum, the only Subantarctic orchids; the royal penguin; and the Antipodean albatroos.
The flora and fauna of Antarctica and the Antarctic Islands (south of 60° south latitude) are protected by the Antarctivc Treaty.
Biotic features
- Strong Winds
- little precipitaion (rainfall)
- short summer days
- very long and cold winters
- poor soil
- permafrost-a layer of permanently frozen subsoil
Arctic tundra contains areas of stark landscape and is frozen for much of the year. The soil there is frozen from 25–90 cm (10–35 in) down, and it is impossible for trees to grow. Instead, bare and sometimes rocky land can only support low growing plants such as moss, heath (Ericaceae varieties such as crowberry and black bearberry), and lichen. There are two main seasons, winter and summer, in the polar tundra areas. During the winter it is very cold and dark, with the average temperature around −28 °C (−18 °F), sometimes dipping as low as −50 °C (−58 °F). However, extreme cold temperatures on the tundra do not drop as low as those experienced in taiga areas further south (for example, Russia's and Canada's lowest temperatures were recorded in locations south of the tree line). During the summer, temperatures rise somewhat, and the top layer of the permafrost melts, leaving the ground very soggy. The tundra is covered in marshes, lakes, bogs and streams during the warm months. Generally daytime temperatures during the summer rise to about 12 °C (54 °F) but can often drop to 3 °C (37 °F) or even below freezing. Arctic tundras are sometimes the subject of habitat conservationprograms. In Canada and Russia, many of these areas are protected through a national Biodiversity Plan.
The tundra is a very windy area, with winds often blowing upwards of 50–100 km/h (30–60 mph). However, in terms of precipitation, it is desert-like, with only about 15–25 cm (6–10 in) falling per year (the summer is typically the season of maximum precipitation). Although precipitation is light, evaporation is also relatively minimal. During the summer, the permafrost thaws just enough to let plants grow and reproduce, but because the ground below this is frozen, the water cannot sink any lower, and so the water forms the lakes and marshes found during the summer months. There is a natural pattern of accumulation of fuel and wildfire which varies depending on the nature of vegetation and terrain. Research in Alaska has shown fire-event return intervals, (FRIs) that typically vary from 150 to 200 years with dryer lowland areas burning more frequently than wetter highland areas.
The biodiversity of the tundras is low: 1,700 species of vascular plants and only 48 land mammals can be found, although millions of birds migrate there each year for the marshes. There are also a few fish species such as the flatfish. There are few species with large populations. Notable animals in the Arctic tundra include caribou (reindeer), musk ox, arctic hare, arctic fox, snowy owl, lemmings, and polar bears (only the extreme north).Tundra is largely devoid of poikilotherms such as frogs or lizards.
Due to the harsh climate of the Arctic tundra, regions of this kind have seen little human activity, even though they are sometimes rich in natural resources such as oil and uranium. In recent times this has begun to change in Alaska, Russia, and some other parts of the world.
Adaptation
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.Some common adaptations of resident animals in the arctic and alpine tundra:
- short and stocky arms and legs.
- thick, insulating cover of feathers or fur.
- color changing feathers or fur: brown in summer, and white in winter.
- thick fat layer gained quickly during spring in order to have continual energy and warmth during winter months.
- many tundra animals have adapted especially to prevent their bodily fluids from freezing solid.
- resident animals like the ptarmigan and the ground squirrel use solar heating to stay warm and save energy. Both animals stay out in the sun to warm up and during the summer when the weather is warm, seek shade to cool off.
Insects
Not only do animals have to keep warm, but insects needed to develop ways to prevent freezing of their bodily fluids. Like tundra animals, insects also use the sun to keep warm. Insects are also dark in color and hairy for the same reason animals are. Being small also makes it easier for tundra insects to keep warm. However, it also makes them more prone to freezing. This is why insects of the tundra have built up antifreeze agents in their bodies to prevent their cells from freezing. Some insects even dehydrate so that there will be less body fluid to freeze. Some insects and animals, along with solar heating, use supercooling to prevent fluids from freezing. Supercooling allows the animals or insects body fluids to cool below freezing without becoming solid. Very little of the supercooled animals and insects' bodies freeze anyway, because they clean their bodies of ice producing nuclei.
Diets
Animals and insects are obviously well adapted to the tundra's climate. Their diets must also be adaptable. If their diets were not adaptable, many of the tundra's animals and insects would starve in the winter because of the lack of certain types of food. An example of this type of adaptation is the diet of the brown bear. In the spring, since food is still scarce, bears may dig up roots or even eat seaweed found along water sides. In the summer the brown bear's diet is more complete. They will hunt for salmon and eat berries.
Since the tundra is the youngest biome, some tundra plants, insects, and animals, can also be found in other biomes. For example, brown bears and caribou can also be found in the taiga biome.
- short and stocky arms and legs.
- thick, insulating cover of feathers or fur.
- color changing feathers or fur: brown in summer, and white in winter.
- thick fat layer gained quickly during spring in order to have continual energy and warmth during winter months.
- many tundra animals have adapted especially to prevent their bodily fluids from freezing solid.
- resident animals like the ptarmigan and the ground squirrel use solar heating to stay warm and save energy. Both animals stay out in the sun to warm up and during the summer when the weather is warm, seek shade to cool off.
Insects
Not only do animals have to keep warm, but insects needed to develop ways to prevent freezing of their bodily fluids. Like tundra animals, insects also use the sun to keep warm. Insects are also dark in color and hairy for the same reason animals are. Being small also makes it easier for tundra insects to keep warm. However, it also makes them more prone to freezing. This is why insects of the tundra have built up antifreeze agents in their bodies to prevent their cells from freezing. Some insects even dehydrate so that there will be less body fluid to freeze. Some insects and animals, along with solar heating, use supercooling to prevent fluids from freezing. Supercooling allows the animals or insects body fluids to cool below freezing without becoming solid. Very little of the supercooled animals and insects' bodies freeze anyway, because they clean their bodies of ice producing nuclei.
Diets
Animals and insects are obviously well adapted to the tundra's climate. Their diets must also be adaptable. If their diets were not adaptable, many of the tundra's animals and insects would starve in the winter because of the lack of certain types of food. An example of this type of adaptation is the diet of the brown bear. In the spring, since food is still scarce, bears may dig up roots or even eat seaweed found along water sides. In the summer the brown bear's diet is more complete. They will hunt for salmon and eat berries.
Since the tundra is the youngest biome, some tundra plants, insects, and animals, can also be found in other biomes. For example, brown bears and caribou can also be found in the taiga biome.
Climatograph
Symbiosis
Mutualism
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A relation where both the organisms benefit from each other is known as mutualism. One of the most well-known tundra plants is lichens. Lichen is a composite organism that is usually made up of a fungus and a green alga or cyanobacterium. The alga is photosynthetic in nature and so, reduces carbon dioxide into sugars that feeds the fungus as well. The fungal counterpart in the meantime, helps provide protection to the alga by retaining water and helping in obtaining minerals from substrate. Thus, both the fungus and the green alga benefit from this relation.
An example of mutualism in the Arctic Tundra is lichen. The fungal hyphae surrounds the agal cells protecting it and providing it with water and salts. The algal cells in return provide the hyphae with sugars and oxygen.
An example of mutualism in the Arctic Tundra is lichen. The fungal hyphae surrounds the agal cells protecting it and providing it with water and salts. The algal cells in return provide the hyphae with sugars and oxygen.
Parasitism
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Parasitism is a relation between two organisms where one organism benefits whereas the other one is at a loss in the relation. One of the lesser known tundra facts is that even parasitism is seen in the tundra region. This is usually seen in cases of liver tapeworm cysts. The liver tapeworm cysts tend to stay and grow in the body of various animals like moose, caribou and even wolves. These tapeworms then feed on the food that is eaten by these animals, which leads to malnutrition in the host body, that is, in the animal.
An example of parsitism in tundra is tapeworm in caribou. The tape worm takes in the nutrients in the caribou. Soon the caribou dies and the tapeworm gets its food.
An example of parsitism in tundra is tapeworm in caribou. The tape worm takes in the nutrients in the caribou. Soon the caribou dies and the tapeworm gets its food.
Commensalism
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Needless to say, one of the tundra climate facts is that the harsh coldness isn't exactly one of the most friendly environment for vegetation growth. Hence, the options that animals in these regions have are very limited. The caribou or reindeers tend to feed on lichens when the weather is at its worst and coldest, as more often than not, this is the only food available to them which can provide them with carbohydrates and can give them energy and heat. So, when the caribou is on the lookout for food, the arctic fox follows it. Then, when the caribou digs the ground snow in a quest to find food, it digs up the soil and slightly exposes, or at least brings closer to the surface some of the subnivean mammals, with whom the arctic fox shares a predator prey relationships in the tundra. So, once the caribou is done with its hunting, the arctic fox then follows and digs further deep and gets its food in the form of the mammals. Hence, this is one of the best examples of commensalism in the tundra region, wherein the caribou remains unaffected but the arctic fox manages to get its food with some help from the caribou.
The barren ground caribou and the arctic fox have a commensalistic relationship. The fox follows the caribou who removes the snow covering to get at lichens under the soil. The fox then hunts the subnivean mammals that have been unearthed by the caribou
The barren ground caribou and the arctic fox have a commensalistic relationship. The fox follows the caribou who removes the snow covering to get at lichens under the soil. The fox then hunts the subnivean mammals that have been unearthed by the caribou
Predation
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The tundra may be a cold, harsh climate, but it is home to a variety of plant and animal life. The food chain ranges from lichens at the bottom to wolves at the top, and a thriving parasitism cycle exists for many organisms in between. These parasites include worms, ticks, and insects.
Wolf and caribou:A wolf is the predator of the caribou to transfer energy. The caribou eats plants and the wolf eats the caribou to obtain the energy from the plant that was eaten by the caribou. It doesn't obtain as much energy as it would by eating the plant directly but it still gets some energy.
Wolf and caribou:A wolf is the predator of the caribou to transfer energy. The caribou eats plants and the wolf eats the caribou to obtain the energy from the plant that was eaten by the caribou. It doesn't obtain as much energy as it would by eating the plant directly but it still gets some energy.
competition
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An example of competition could be between a musk ox and a caribou. A musk ox's diet consists of plants such as sedges and grasses, while a caribou's is made of berries, grass and sedge. When food is hard to find musk ox and caribou might have some competition trying to get something to eat. Might be hard to find a musk ox fighting for a sedge with a caribou, though.
Why is symbiosis important
Symbiosis is the close association between individuals of different species, occurring within a whole community. It is the interactions of different species and it is important to maintain a healthy ecosystem.
Top predators are the animals that occupy the position at the top of a food web. Examples of top predators include sharks and wolves. Top predators play an important role in maintaining the balance and biodiversity of an ecosystem. If the top predator is removed from the delicate balance of any particular ecosystem, there may be disastrous effects for the other plants and animals that inhabit the environment.
Another problem involving the loss of vegetation is the competition that is created between herbivorous species. Competition between species for the remaining plant life is high and weaker species lose out to stronger ones, leading to the potential loss of weaker animals, as well as plant species. Increased competition, therefore, leads to a lack of biodiversity. In contrast, top predators often have varied diets, which means they can pursue a new food source if one is running low, preventing the first source from being eradicated completely. This is one of the ways that top predators are able to maintain biodiversity and the balance of an ecosystem.
Predators are normally bigger so they need more food.Each predator has to kill many prey animals a year to survive and the prey animals have to be numerous enough to reproduce and survive. Too few prey animals and the predators starve to death. In a healthy ecosystem predators and prey reach a balance so that there are always enough prey animals to continue reproducing. This ensures a permanent supply of food for the predators. If the predators over hunt the prey animal, the population of prey will decline causing the predators to starve.The ecosystem will not also be balanced if there are more predators than preys.
Another problem involving the loss of vegetation is the competition that is created between herbivorous species. Competition between species for the remaining plant life is high and weaker species lose out to stronger ones, leading to the potential loss of weaker animals, as well as plant species. Increased competition, therefore, leads to a lack of biodiversity. In contrast, top predators often have varied diets, which means they can pursue a new food source if one is running low, preventing the first source from being eradicated completely. This is one of the ways that top predators are able to maintain biodiversity and the balance of an ecosystem.
Predators are normally bigger so they need more food.Each predator has to kill many prey animals a year to survive and the prey animals have to be numerous enough to reproduce and survive. Too few prey animals and the predators starve to death. In a healthy ecosystem predators and prey reach a balance so that there are always enough prey animals to continue reproducing. This ensures a permanent supply of food for the predators. If the predators over hunt the prey animal, the population of prey will decline causing the predators to starve.The ecosystem will not also be balanced if there are more predators than preys.