Ice desert. Arctic desert - typical animals, birds. The story of the animal world of the Arctic deserts: photos, pictures, videos Arctic desert soil plants animals

11.03.2020

Snow cover, lying all year round or thawing only for a short time, are the main conditions that determine life in the polar regions.

polar deserts

Zones of the Arctic and Antarctic deserts are also common in Antarctica. They formed during the long polar night and extremely low temperatures. Only 10-12 days a year the temperature rises above 0 C, and the topsoil has time to thaw for a short time.

Most of the territory is occupied by glaciers. Mosses and lichens grow on ice-free areas. There are only two species of flowering plants, and there are several more in the Arctic. Arctic species include polar poppy, snow buttercup, and saxifrage. There is almost no humus horizon in primitive arctic soils.

The animal world is poor. Only on the rocky coasts in summer the life of noisy bird colonies is in full swing, where guillemots and auks, gulls and guillemots nest. On the coasts there are large animals (walruses, seals) that feed on fish and crustaceans. In the Northern Hemisphere in the Arctic there are large mammals - polar bears. Their main food is fish and seals. In the southern hemisphere, in the harsh Antarctic, penguins nesting on the coasts in the Antarctic oases feel best, where the air temperature is higher than in the surrounding area.

tundra

Tundras are common in North America. In Russia, they occupy the second largest area after the taiga. Tundras are almost absent in the Southern Hemisphere.

A typical tundra is a treeless expanse with low and not always continuous vegetation cover. The main vegetation of the tundra is mosses and lichens. Dwarf birch, polar willow, partridge grass also grow here. They, as if clinging to the ground, form a kind of "pillow". Many shrubs - lingonberries, cloudberries, cranberries - are evergreen. In the short summer, the tundra blossoms. The soils of the tundra are often swampy and extremely poor in humus, but rich in semi-decomposed plant remains - peat.

The fauna of the tundra cannot be called diverse. Polar geese, swans, sandpipers nest along the shores of tundra lakes. Numerous inhabitants of the tundra - lemmings - are the main food for arctic foxes and snowy owls.

The largest animal of the tundra is the reindeer. It feeds on lichen moss. Many animals and almost all birds move to for the winter. It extends along the border of the tundra in a narrow strip. It is an alternation of tundra and forest areas.

The Arctic (translated from Greek, bear) is the edge of the northern land, where in summer the sun does not set beyond the sunset line. And in winter, severe frosts reign here, hurricane-force winds that cause strong snowstorms and a polar night that lasts from 98 to 127 days. At the North Pole itself, it lasts six months. And the only sources of light here in winter are the stars, the moon and the twinkling aurora. The Arctic is divided into arctic deserts of the earth, ice and polar. Simply put, on the territory of eternal snow and ice and patches of land with vegetation. The climate of the Arctic deserts, in view of their location in the natural zone, part of the geographical zone adjacent to the Arctic Ocean, is very cold and harsh. That is why they call this region of the Arctic deserts, the zone of eternal snow and ice. The arctic deserts of the earth are nothing but varieties of deserts, with very sparse and poor vegetation, among the ice and snow of the arctic belt of the earth.

Such deserts are distributed almost throughout Greenland, the northern part, most of North America, falling on the Canadian Arctic Archipelago and on a significant part of the islands with complex mountainous terrain, located in the icy ocean and having their own unique climate of the Arctic deserts. The cold climate of the Arctic deserts makes it impossible for vegetation to grow in abundance. Since, in short summers, the air temperature does not rise above 0 ° +5 °, in winter its average weighted temperature ranges from 10-35 °, and in the Greenland and Asian North to -50 °, -60 ° Celsius. Precipitation does not exceed the fallen rate of 200 - 400 millimeters per year. The Arctic deserts of the earth, during a short-term snowmelt, have insignificant land areas isolated by snow and ice - polar oases, where lichens, scale mosses and herbaceous vegetation in the form of sedge and simple grasses grow predominantly, up to approximately five tons of green mass per hectare. This is very, very little. But no matter how severe arctic desert climate, nature decreed that during the short cold summer, insignificant stony and swampy areas of soil freed from snow cover with beautiful colors that grow here, some types of flowers, such as buttercup, saxifrage, foxtail, polar poppy. Many of these plants, the peoples inhabiting the Far North, are considered medicinal. And for most of the animals common here, sparse vegetation is the main source of food. The almost never changing climate of the Arctic deserts has adapted for itself a small number of animal species that have chosen the territories of the harsh Arctic deserts. Here in this land, you can meet such animals as the polar fox, the "owner" of these glacial places, the polar bear, the Greenland musk bull, the small rodent lemming (pied), often in the summer, you can also see the polar hare, which was initially considered by scientists to be a hare .
The climate of the Arctic deserts, with its severity, did not affect the families of birds living here. Waders, geese, eiders, guillemots, guillemots, glaucous gulls, which from year to year, arriving here, collect their multi-million bird colonies here. And for such mammals as beluga whales, seals, ringed seals, sea seals, walruses, only the climate of the Arctic deserts and their immediate habitat, the Laptev Sea and the Kara Sea, are suitable for living. In the cold, phytoplankton is found in abundance and in sufficient quantities, such fish as nelma, cod, arctic cod, vendace. The Arctic deserts of the land, which polar bears have chosen, have been declared reserves, one of these is called Wrangel Island, the surface area of which is a continuous glacier strewn with broken stone and rubble. The climate of the Arctic deserts owes its formation not only to the low temperature of high latitude, but also to thermal reflection (albedo) during the daytime, from the surface of ice and snow, which is held in the Arctic, all year round. In summer, when the air temperature rises above zero, the effect of thermal reflection leads to a significant evaporation of moisture from the surface of the glaciers, so the sky of the Arctic deserts is almost constantly covered with low-weight lead clouds. It rains constantly, often with snow. Evaporation of water from the ocean opened from the ice contributes to the formation of thick fogs. Not the last influential role on the climate of the Arctic deserts is exerted by the underwater East Greenland Current and the clockwise movement of the ice field in the ocean caused by it with the ongoing removal of drifting ice into the Atlantic Ocean. An exceptionally last and no less important role in the climate of the Arctic deserts is played by permafrost, which fetters the land and waters of the Arctic with centuries of ice. The thickness of the permafrost ice shell ranges from 100 - 150 meters in the area of Franz Josef Land in the northern regions of the Taimyr Peninsula to 500 - 550 meters and over 680 meters on Novaya Zemlya. In some mountainous and elevated places, ice from the mainland, breaking off, slides into the ocean, forming giant floating icebergs. In such a natural way, mother herself - nature supports and regulates the harsh climate of the Arctic deserts.

The Arctic Desert, the northernmost of all natural zones, is part of the Arctic geographical zone and is located in the latitudes of the Arctic, stretching from Wrangel Island to the Franz Josef Land archipelago. This zone, which consists of all the islands of the Arctic Basin, is mostly covered with glaciers and snow, as well as rock fragments and rubble.

Arctic desert: location, climate and soil

The arctic climate means long, harsh winters and short cold summer without transitional seasons and with frosty weathering. In summer, the air temperature barely reaches 0 ° C, it often rains with snow, the sky is overcast with gray clouds, and the formation of thick fogs is due to the strong evaporation of ocean water. Such a harsh climate is formed both in connection with the critically low temperature of high latitudes, and due to the reflection of heat from the surface of ice and snow. For this reason, animals inhabiting the zone of the Arctic deserts have fundamental differences from representatives of the fauna living in continental latitudes - they are much easier to adapt to survive in such harsh climatic conditions.

The glacier-free space of the Arctic is literally shrouded in permafrost, therefore, the process of soil formation is at the initial stage of development and is carried out in a poor layer, which is also characterized by the accumulation of manganese and iron oxides. On fragments of various rocks, characteristic iron-manganese films are formed, which determine the color of the polar desert soil, while solonchak soils form in coastal areas.

There are practically no large stones and boulders in the Arctic, but small flat cobblestones, sand and, of course, the famous spherical concretions of sandstone and silicon, in particular, spherulites, are found here.

Vegetation of the arctic desert

The main difference between the Arctic and the tundra is that in the tundra there is the possibility of existence for a wide range of living creatures that can feed on its gifts, and in the Arctic desert it is simply impossible to do this. It is for this reason that there is no indigenous population on the territory of the Arctic islands and very few representatives of flora and fauna.

The territory of the Arctic desert is devoid of shrubs and trees, there are only isolated from each other and small areas with lichens and mosses of rocks, as well as various rocky soil algae. These small islands of vegetation resemble an oasis among the endless expanses of snow and ice. The only representatives of herbaceous vegetation are sedge and grasses, and flowering plants are saxifrage, polar poppy, alpine foxtail, ranunculus, grains, bluegrass and arctic pike.

Wildlife of the Arctic Desert

The terrestrial fauna of the northern region is relatively poor due to very sparse vegetation. Almost the only representatives of the animal world of the ice deserts are birds and some mammals.

The most common birds are:

In addition to the permanent inhabitants of the Arctic skies, migratory birds also appear here. When the day comes in the north, and the air temperature gets higher, birds from the taiga, tundra and continental latitudes arrive in the Arctic, therefore, black geese, white-tailed sandpipers, white geese, brown-winged plovers, ringed beetles, upland buzzards and dunlin periodically appear off the coast of the Arctic Ocean . With the onset of the cold seasons, the above species of birds return to the warmer climes of more southern latitudes.

Among the animals, one can distinguish the following representatives:

reindeer;
lemmings;
White bears;
hares;
seals;
walruses;
arctic wolves;
arctic foxes;
musk oxen;
beluga whales;
narwhals.

Polar bears have long been considered the main symbol of the Arctic, leading a semi-aquatic lifestyle, although the most diverse and numerous inhabitants of the harsh desert are sea birds that nest on cold rocky shores in summer, thereby forming "bird colonies".

Adaptation of animals to the arctic climate

All of the above animals forced to adapt to life in such harsh conditions, so they have unique adaptive features. Of course, the key problem of the Arctic region is the possibility of maintaining the thermal regime. To survive in such a harsh environment, it is with this task that animals must successfully cope. For example, arctic foxes and polar bears are saved from frost thanks to warm and thick fur, loose plumage helps birds, and for seals, their fat layer is saving.

An additional rescue of the animal world from the harsh Arctic climate is due to the characteristic color acquired immediately by the onset of the winter period. However, not all representatives of the fauna, depending on the season, can change the color given to them by nature, for example, polar bears remain the owners of snow-white fur throughout all seasons. The natural pigmentation of predators also has advantages - it allows them to successfully hunt and feed the whole family.

Interesting inhabitants of the icy depths of the Arctic

Arctic deserts (polar desert, ice desert), a kind of desert with extremely sparse sparse vegetation among the snows and glaciers of the Arctic and Antarctic belts of the Earth. It is distributed over most of Greenland and the Canadian Arctic Archipelago, as well as on other islands of the Arctic Ocean, on the northern coast of Eurasia and on islands near Antarctica.
In the Arctic desert grow small isolated areas with mainly scale mosses and lichens and herbaceous vegetation. They look like a kind of oases among the polar snows and glaciers. In the conditions of the Arctic desert, there are some types of flowering plants: polar poppy, foxtail, buttercup, saxifrage, etc.

Arctic soils are found in the area of polar deserts and semi-deserts under "spots" of vegetation on the islands of the Arctic Ocean and in a narrow strip along the Asian coast of the mainland. Soil processes are poorly developed, and the soil profile is practically not expressed. Rare mosses and lichens practically do not provide “material” for the formation of humus, their humus horizon is rarely thicker than 1 cm. 5 m. Due to insufficient moisture, gleying is absent in arctic soils, soils have a neutral acid reaction, sometimes carbonate or even saline. In places under algae spots, specific “soil-films” are distinguished with subtle signs of soil formation.

Typically, Arctic soils consist of a thin (1–3 cm) organogenic horizon and a mineral mass poorly differentiated into horizons, underlain at a depth of 40–50 cm by a permafrost layer. Gleying is weak or absent. Perhaps the presence of carbonates or easily soluble salts. Arctic soils are common on the islands of the Arctic Ocean.

Humus in the upper horizons usually contains a small amount (1-2%), but sometimes reaches large values (up to 6%). Its fall with depth is very sharp. Soil reaction is neutral (pHH2O 6.8-7.4). The sum of exchange bases does not exceed 10-15 meq per 100 g of soil, but the degree of saturation with bases is almost complete - 96-99%. In desert-arctic soils, mobile iron can accumulate in significant amounts.

Arctic soils can be divided into two subtypes: 1) arctic desert and 2) arctic typical humus. The current level of knowledge of these soils allows us to distinguish two types within the first subtype: a) saturated and b) carbonate and saline.
Arctic desert carbonate and saline soils are characteristic of the superarid (precipitation less than 100 mm) and cold parts of the Arctic and the oases of Antarctica. The American scientist J. Tedrow calls these soils polar desert. They are found in the north of Greenland, in the northernmost part of the Canadian Arctic archipelago. These arctic soils are neutral to slightly alkaline and have a salt crust on the surface. Arctic desert saturated soils differ from those described by the absence of new formations of readily soluble salts and carbonates in the upper part of the profile.

The following should be considered the most characteristic features of Arctic soils:

1) the complexity of the soil cover associated with the nature of the microrelief, polygonality;

2) shortening of the profile due to the low intensity of soil-forming processes and shallow seasonal thawing;

3) incompleteness and non-differentiation of the soil profile due to the low intensity of the movement of substances;

4) significant skeletal structure due to the predominance of physical weathering;

5) lack of gleying associated with a small amount of precipitation.

Low summer temperatures, scarce flora and a layer of permafrost interfere with the normal soil-forming process. During the season, the thawed layer does not exceed 40 cm. The soil thaws only in the middle of summer, and by the beginning of autumn it freezes again. Waterlogging during the thawing period and summer drying lead to cracking of the soil cover. In the greater part of the Arctic, almost no formed soils are observed, but only coarse detrital material in the form of placers.

Antarctic and Arctic desert: soil, soil characteristics and features

Lowlands and their fine-earth soil are the basis of Arctic soils (very thin, without any signs of claying). Arctic ferruginous, slightly acidic, almost neutral soils are brown in color. These soils are complex, associated with microreliefs, soil compositions and vegetation. Scientific citation: "The main specific feature of the Arctic soils is that they are, as it were, a "complex" of soils with a normally developed profile under plant sods and with a reduced profile under algal soil films" gives a complete description of Arctic soils and explains the peculiarities of the flora of this region.

Characteristics of the Arctic Desert

The Arctic Desert is part of the Arctic geographical zone, located in the high latitudes of the Arctic. The zone of the Arctic deserts - the northernmost of the natural zones - is located in the high latitudes of the Arctic. Its southern border is located approximately at the 71st parallel (Wrangel Island). The Arctic desert zone extends to about 81° 45′ N. sh. (islands of the Franz Josef Land archipelago). The zone of the Arctic deserts includes all the islands in the Arctic basin: this is the island of Greenland, the northern part of the Canadian archipelago, the Svalbard archipelago, the islands of the archipelagos of Franz Josef Land, Severnaya Zemlya, Novaya Zemlya, the New Siberian Islands and a narrow strip along the coast of the Arctic Ocean within the Yamal Peninsulas, Gydan, Taimyr, Chukchi). These spaces are covered with glaciers, snow, rubble and rock fragments.

The climate of the Arctic desert

The climate is arctic, with long and severe winters, summers are short and cold. Transitional seasons in the Arctices which desert does not exist. During the polar night - winter, and during the polar day - summer. The polar night lasts 98 days at 75°N. sh., 127 days — by 80°C. sh. Average winter temperatures are -10 to -35°, dropping to -60°. Frost weathering is very intense.

The air temperature in summer is slightly above 0°C. The sky is often overcast with gray clouds, it rains (often with snow), due to the strong evaporation of water from the surface of the ocean, thick fogs form.

Even on the "southern" island of the Arctic desert - Wrangel Island - according to eyewitnesses, there is no autumn, winter comes immediately after the short Arctic summer.

Soils of the Arctic deserts

The wind changes to the north and winter comes overnight.

The Arctic climate is formed not only due to the low temperatures of high latitudes, but also in view of the reflection of heat from the snow and ice crust. And the ice and snow covers last about 300 days a year.

The annual amount of atmospheric precipitation is up to 400 mm. Soils are saturated with snow and barely thawed ice.

Vegetablecover

The main difference between the desert and the tundra is that you can live in the tundra, subsisting on its gifts, but this is impossible to do in the Arctic desert. That is why there were no indigenous people on the territory of the Arctic islands.

The territory of the Arctic deserts has open vegetation, which covers about half of the surface. The desert is devoid of trees and shrubs. There are small isolated areas with crustaceous lichens on rocks, mosses, various algae on stony soils and herbaceous vegetation - sedges and grasses. In the conditions of the Arctic desert, there are some types of flowering plants: polar poppy, grains, chickweed, alpine foxtail, arctic pike, bluegrass, buttercup, saxifrage, etc. These islands of vegetation look like oases among endless ice and snow.

The soils are thin, with insular distribution mainly under vegetation. The spaces free from glaciers are bound by permafrost, the thawing depth does not exceed 30-40 cm even under polar day conditions. Soil formation processes are carried out in a thin active layer and are at the initial stage of development.

The upper part of the soil profile is characterized by the accumulation of iron and manganese oxides. Iron-manganese films are formed on rock fragments, which determines the brown color of polar desert soils. In coastal areas saline by the sea, polar-desert solonchak soils are formed.

There are practically no large stones in the Arctic desert. Mostly sand and small flat cobblestones. There are spherical concretions, which consist of silicon and sandstone, from a few centimeters to several meters in diameter. The most famous concretions are spherulites on Champa Island (FJL). Every tourist considers it his duty to take a photo with these balloons.

Animal world

Due to the sparse vegetation, the fauna of the Arctic deserts is relatively poor. Terrestrial fauna is poor: Arctic wolf, arctic fox, lemming, Novaya Zemlya deer, in Greenland - musk ox. On the coast you can meet pinnipeds: walruses and seals.

Polar bears are considered the main symbol of the Arctic. They lead a semi-aquatic lifestyle, the key land areas for breeding polar bears are the northern coast of Chukotka, Franz Josef Land, Cape Zhelaniya on Novaya Zemlya. On the territory of the reserve "Wrangel Island" there are about 400 ancestral dens, so it is called the "maternity hospital" of the bear.

The most numerous inhabitants of the harsh northern region are birds. These are guillemots, puffins, eiders, pink gulls, snowy owls, etc. Sea birds nest on the rocky shores in summer, forming "bird colonies". The largest and most diverse seabird colony in the Arctic nests on Rubini Rock, which is located in the ice-free Tikhaya Bay off Hooker Island (FJL). The bird market on this rock has up to 18 thousand guillemots, guillemots, kittiwakes and other sea birds.

What is the soil like in the Arctic deserts?

Arctic soils are well-drained soils of the high Arctic and Antarctic, formed in a polar cold dry climate (precipitation 50-200 mm, July temperature not higher than 5 ° C, average annual temperatures are negative - from -14 to -18 ° C) under a lichen film and cushions of mosses and flowering plants (higher plants on watersheds they occupy less than 25% of the surface or they are absent at all) and are characterized by an underdeveloped thin soil profile of the A-C type.

The type of arctic soils was introduced into the taxonomy of Russian soils by E. N. Ivanova. The basis for identifying a special type of soil in the high Arctic was the work of domestic and foreign researchers on the islands of the Arctic Ocean.

In the Antarctic, the vegetation cover is represented only by scale lichens and mosses; in rock crevices and on fine-earth substrates, green and blue-green algae play an important role in the accumulation of organic matter in primitive arctic soils. In the high-latitude Arctic, due to warmer summers and less severe winters, flowering plants appear. However, as in Antarctica, mosses, lichens, and various types of algae play a big role. Vegetation cover is confined to frost cracks, drying cracks and depressions of another genesis. Above 100 m above sea level, vegetation is practically absent. The main types of distribution of plant sod are curtain-cushion and polygonal-mesh. Bare soil occupies from 70 to 95%.

Soils thaw by only 30-40 cm and for a period of about one and a half months. In spring and early summer, the profile of Arctic soils is strongly waterlogged due to stagnant moisture formed during the melting of soil ice above the frozen horizon; in summer, the soil from the surface dries up and cracks due to round-the-clock insolation and strong winds.

The differentiation of Arctic soils in terms of gross chemical composition is very weak. Only some accumulation of sesquioxides in the upper part of the profile and a rather high background of iron content can be noted, which is associated with the cryogenic uptake of iron, which is mobilized under conditions of a seasonal change in aerobic and anaerobic conditions. The cryogenic uptake of iron in the soils of the Arctic deserts is better expressed than in any other permafrost soils.

Organic matter in soils in areas with vegetative sod contains from 1 to 4%.

The ratio of humic acid carbon to fulvic acid carbon is about 0.4-0.5, often even less.

The generalized materials of I. S. Mikhailov indicate that Arctic soils, as a rule, have a slightly acidic reaction (pH 6.4-6.8), with depth the acidity decreases even more, sometimes the reaction can even be slightly alkaline. The absorption capacity fluctuates around 12–15 mEq per 100 g of soil at almost complete saturation with bases (96–99%). Sometimes there is a weak removal of calcium, magnesium and sodium, but it is replenished by impulsation of sea salts. As a rule, typical arctic soils do not contain free carbonates, except when soils develop on carbonate rocks.

Arctic soils can be divided into two subtypes: 1) arctic desert and 2) arctic typical humus. The current level of knowledge of these soils allows us to distinguish two types within the first subtype: a) saturated and b) carbonate and saline.

Arctic desert carbonate and saline soils are characteristic of the superarid (precipitation less than 100 mm) and cold parts of the Arctic and the oases of Antarctica. The American scientist J. Tedrow calls these soils polar desert. They are found in the north of Greenland, in the northernmost part of the Canadian Arctic archipelago. These arctic soils are neutral to slightly alkaline and have a salt crust on the surface. Arctic desert saturated soils differ from those described by the absence of new formations of easily soluble salts and carbonates in the upper part of the profile.

Arctic typical humus soils are characterized by a slightly acidic or neutral reaction, have somewhat larger reserves of humus than the soils of the first subtype, are formed under soddy areas of polygons, they do not have salt accumulations. This subtype of arctic soils is predominant in the Soviet Arctic.

The most characteristic features of arctic soils the following should be considered: 1) the complexity of the soil cover associated with the nature of the microrelief, polygonality; 2) shortening of the profile due to the low intensity of soil-forming processes and shallow seasonal thawing; 3) incompleteness and non-differentiation of the soil profile due to the low intensity of the movement of substances; 4) significant skeletal structure due to the predominance of physical weathering; 5) the absence of gleying associated with a small amount of precipitation.

The territories of the Arctic and Antarctic lie outside the limits of human agricultural activity. In the Arctic, these areas can only be used as hunting grounds and reserves for the conservation and maintenance of the number of rare animal species (polar bear, musk ox, Canadian white goose, etc.).

arctic desert

Karavaeva.

The development of Arctic soils is influenced by permafrost and permafrost, which thaws only in a short summer period (1.5 ... 2.0 months) to a depth of 30 ... 50 cm, and the temperature of the active layer is close to zero at this time. Permafrost (cryogenic) processes predominate - cracking, freezing, wrestling, due to which fissure polygons are formed on loose rocks and stone hills, rings, bands on stone rocks. Physical weathering dominates, leading to the formation of a coarse clastic, weakly biogenic, weakly leached weathering crust. Geochemical and biochemical weathering is very slow, and from the end of August to the beginning of July it is absent. The soil cover on the watersheds is focal, not continuous - separate areas of Arctic soils against the background of soil films under algae patches (1 ... 2 cm thick).

The soil cover is formed only in areas with fine earth fragmentarily under vegetation that develops selectively in accordance with the conditions of relief, exposure, moisture, and the nature of parent rocks. The soils are characterized by a peculiar polygonality: the soils are broken by vertical frost cracks. The soil profile is shortened (up to 40...50 cm), but its thickness often changes, sometimes with wedging out of individual horizons. Soils (up to 40 cm) are poorly differentiated into horizons, the humus horizon is less than 10 cm. In addition to permafrost phenomena, they are characterized by a small supply of organic residues (0.6 t/ha), the absence of an Ao acid litter horizon, an illuvial horizon, and the presence of strong stonyness on the surface. The soil horizons contain a lot of skeletal material. They lack gleying due to low moisture and significant aeration. These soils are characterized by cryogenic accumulation of iron compounds, weak movement of substances along the profile or their absence, high saturation (up to 90%) with bases, weakly acidic, neutral, sometimes slightly alkaline reaction.

In the Arctic zone, a type has been identified - arctic desert soils, which includes two subtypes: desert-arctic and arctic typical soils.

Desert-Arctic soils are common in the northern part of the Arctic zone on leveled areas, often with sandy loam and sandy-rubbly deposits under moss-lichen clumps with single specimens of flowering plants. Large areas are under sands, rubble, eluvial and deluvial deposits and stone embankments. Their surface is broken by a system of polygons with cracks up to 20 m.

The thickness of the soil profile is on average up to 40 cm. It has the following structure: A1 - humus horizon 1 ... 2 cm thick, less often up to 4 cm, from dark brown to yellowish-brown in color, sandy or light loamy, with a fragile granular structure, uneven or noticeable transition to the next horizon; A1C - transitional horizon 20 ... 40 cm thick, brown or yellow-brown in color, less often spotty, sandy loam, fragile-small-cloddy or structureless, transition along the thawing boundary; C - frozen soil-forming rock, light brown, sandy loam, dense, gravel.

Humus in horizon A1 contains only 1 ... 2%. Soil reaction is neutral and slightly alkaline (рН 6.8…7.4). The sum of exchangeable bases ranges from 5...10 to 15 mg equiv/100 g of soil. The degree of saturation with bases is 95 ... 100%. The water regime is stagnant (permafrost). At the beginning of summer, when snow and glaciers melt, the soils become waterlogged, and in summer they quickly dry out due to round-the-clock insolation and strong winds.

In depressions with stagnant waters and in areas flooded by the melting flowing waters of snowfields and glaciers, arctic marsh soils are found under moss-grass vegetation. In areas with stagnant waters, gleyed horizons with a heavy granulometric composition are clearly expressed, while in areas flooded by flowing waters, the genetic horizons differ slightly and gleying is absent.

In the mouths of the rivers, marsh solonchaks are developed, and in bird rookeries - biogenic accumulations.

Arctic typical soils are formed on high plateaus, upland watershed elevations, abrasion-accumulative marine terraces, mainly in the south of the Arctic zone, under moss-forb-grass vegetation of frost cracks and drying cracks.

The soil profile is thin - up to 40 ... 50 cm: Ao - moss-lichen litter up to 3 cm thick; A1 - humus horizon up to 10 cm thick, brown-brown, often loamy, unstable granular-cloddy structure, porous, with cracks, compacted, the horizon wedges out in the middle of the polygon; the transition is uneven and noticeable; A1C - transitional horizon (30 ... 40 cm) from light brown to brown, loamy, lumpy-nutty, dense, fissured, transition along the thaw boundary; C - frozen soil-forming rock, light brown, often with rock fragments.

Soils have discrete humus horizons. The profile is predominantly uneven in thickness of the A1 horizon, often with humus pockets. In the A1 horizon, the amount of humus sometimes reaches 4–8% and gradually decreases down the profile. The composition of humus is dominated by fulvic acids (Cgc: Cfc = 0.3…0.5). Inactive calcium fulvates and humates predominate, the content of non-hydrolyzable residue is significant. There are few silty particles; they consist mainly of hydromica and amorphous iron compounds. The absorption capacity is less than 20 mg eq/100 g of soil, the soil absorbing complex is saturated with bases. The degree of saturation with bases is high - 90 ... 100%. Mobile iron contains up to 1000 mg equiv/100 g of soil and more, especially on basalts and dolerites.

The Antarctic Desert is the largest and coldest desert on Earth, characterized by large temperature fluctuations and an almost complete absence of precipitation. It is located in the very south of the planet, completely occupying the sixth continent - Antarctica.

Cold deserts of the Earth

Deserts in all people cause associations with heat, endless expanses of sand and small bushes. However, on Earth there are also cold types of them - these are the Arctic and Antarctic deserts. They are called so because of the continuous ice cover and due to the low temperature, the air cannot retain moisture, so it is very dry.

In terms of precipitation, the objects we are considering resemble southern sultry ones, such as the Sahara, which is why scientists gave them the name “cold deserts”.

The zones of the Arctic and Antarctic deserts are the territories of the continents and adjacent islands at the North Pole (Arctic) and South Pole (Antarctic), related, respectively, to the Arctic and Antarctic climatic zones. They consist of glaciers and stones, they are practically lifeless, but under the ice, scientists find microorganisms.

Antarctica

The territory of the Antarctic desert is 13.8 million square meters, which is the area of the icy continent, which is located in the southern polar part of the world. From different sides it is washed by several oceans: the Pacific, Atlantic and Indian, the coasts consist of glaciers.

The geographical position of the Antarctic deserts that occupy Antarctica is determined not only by the continental zone, but also by the islands located near it. There is also the Antarctic Peninsula, which goes into the depths of the ocean of the same name. On the territory of Antarctica lie dividing the mainland into 2 parts: western and eastern.

The western half is located on the Antarctic platform and is a mountainous area almost 5 km high. Volcanoes are located in this part, one of which - Erebus - active, is located on an island in the Ross Sea. In coastal areas there are oases that do not have ice. These small plains and mountain peaks, called nunataks, have an area of 40 thousand square meters, located on the Pacific coast. On the mainland there are lakes and rivers that appear only in the summer. In total, scientists have discovered 140 subglacial lakes. Only one of them does not freeze - Lake Vostok. The eastern part is the largest in terms of territory and the coldest.

Minerals located in the bowels of the mainland: ferrous and non-ferrous metal ore, mica, graphite, coal, there is information about the reserves of uranium, gold and diamonds. According to the assumptions of geologists, there are deposits of oil and gas, but due to the harsh climate, mining is not possible.

Antarctic deserts: climate

The southern mainland has a very harsh and cold climate, which is due to the formation of cold and dry air currents. Antarctica is located in the Earth's belt.

In winter, the temperature can reach -80 ºС, in summer -20 ºС. More comfortable is the coastal zone, where in summer the thermometer reaches -10 ºС, which occurs due to a natural phenomenon called "albedo" - the reflection of heat from the ice surface. The record for the lowest temperature was recorded here in 1983 and amounted to -89.2 ºС.

The amount of precipitation is minimal, about 200 mm for the whole year, they consist only of snow. This is due to the intense cold that dries out moisture, making the Antarctic desert the driest place on the planet.

The climate here is different: in the center of the mainland there is less precipitation (50 mm), it is colder, on the coast the wind is less intense (up to 90 m / s), and precipitation is already 300 mm per year. Scientists have calculated that the amount of frozen water in the form of ice and snow in Antarctica is 90% of the world's fresh water.

One of the obligatory signs of the desert is storms. Here they also happen, only snowy, and the wind speed during the elements is 320 km / h.

In the direction from the center of the mainland to the coast, there is a constant movement of shelf ice; in the summer months, parts of the glaciers break off, forming massifs of icebergs that drift in the ocean.

Mainland population

There is no permanently resident population in Antarctica; according to its international status, it does not belong to any state. On the territory of the Antarctic desert zone there are only scientific stations where scientists are engaged in research. Sometimes there are tourist or sports expeditions.

The number of scientists-researchers living at scientific stations in the summer increases to 4 thousand people, in the winter - only 1 thousand. According to historical data, the first settlers here were American, Norwegian and British whalers who lived on the island of South Georgia, but with 1966 Whale hunting is banned.

The entire territory of the Antarctic desert is icy silence surrounded by endless expanses of ice and snow.

Biosphere of the southernmost continent

The biosphere in Antarctica is divided into several zones:

the coast of the mainland and the island;
oases located near the coast;
nunatak zone (mountains near Mirny station, mountainous regions on Victoria Land, etc.);
ice sheet zone.

The richest in flora and fauna is the coastal zone, which is home to many Antarctic animals. They feed on zooplankton from sea water (krill). There are no land mammals on the mainland at all.

In nunataks and coastal oases, only bacteria, lichens and algae, worms can live, and birds can occasionally fly in. The most favorable climate zone is the Antarctic Peninsula.

Vegetable world

The plants of the Antarctic deserts are those that appeared millions of years ago, even during the existence of the Gondwana continent. Now they are limited to a few types of mosses and lichens, which, according to scientists, are more than 5 thousand years old.

Flowering plants have been found on the territory of the peninsula and nearby islands, and blue-green algae live in fresh water in oases, which form a crust and cover the bottom of reservoirs.

The number of lichen species is 200, and there are about 70 mosses. Algae usually settle in summer when snow melts and small reservoirs form, and they can be of various colors, creating bright multi-colored spots that resemble lawns from a distance.

Only 2 species of flowering plants have been found:

Colobanthus kito, referring to This is a cushion-shaped herb, decorated with small flowers of white or light yellow shades, about 5 cm in size.
Antarctic meadow grass from the grass family. It grows in sunny areas, tolerates frost well, grows up to 20 cm.

Ice Desert Animals

The fauna of Antarctica is very poor due to the cold climate and lack of food. Animals live only in places where there are plants or zooplankton in the ocean, and are divided into 2 groups: terrestrial and living in the water.

There are no flying insects, because due to the strong cold wind they cannot rise into the air. However, in the oases there are small ticks, as well as wingless flies and springtails. Only in this area lives the wingless midge, which is the largest terrestrial animal of the Antarctic desert - this Belgica Antarctica size 10-11 mm (photo below).

In freshwater reservoirs in the summer, you can find the simplest representatives of the fauna, as well as rotifers, nematodes and lower crustaceans.

Animals of Antarctica

The fauna of Antarctica is also quite limited and is present mainly in the coastal zone:

penguins of 17 species: Adelie, emperor, etc.;
seals: Weddell (up to 3 m long), crabeater and predatory leopard seal (reaches the skin is colored with spots), sea lion, Ross seals (endowed with vocal abilities);
whales that feed on small crustaceans and icefish live in the ocean;
huge jellyfish, reaching 150 kg of weight;
some birds settle here in the summer, creating nests and raising chicks: gulls, albatrosses, white plover, cormorants, big pipit, petrels, pintail.

The most representative animal species is the penguins, of which the emperor penguins are the most common, living on the coast of the mainland. The growth of these beauties can reach a human (160 cm), and weight - 60 kg.

Another numerous representative of birds is the Adélie penguins, the smallest, growing up to 50 cm and weighing no more than 3 kg.

Ecosystem of Antarctica and its conservation

The continental ice deserts and cold waters of the oceans washing Antarctica are an ecosystem inhabited by living organisms that have existed here for thousands of years. The main animal food is phytoplankton.

Due to warming, glaciers and masses of snow in Antarctica are gradually receding, moving closer to the coast. The ice shelves are gradually melting, the soil is gradually exposed, which contributes to creating a more favorable environment for the settlement of plants. However, the appearance of non-native plant species is not at all welcomed on the continent.

The ecosystem of Antarctica and the Antarctic desert needs to be protected from the emergence of "alien" species of life, so every scientist or tourist who comes here undergoes mandatory processing. In the process, it is washed away and destroyed parts of plants or spores.

In accordance with the Treaty, signed by 44 countries of the world, military operations and tests, including nuclear tests, and the disposal of radioactive waste are prohibited on the territory of Antarctica. Only scientific research is allowed.