Arctic deserts. Ice deserts and tundras Arctic desert ice zone

The Arctic Desert, the northernmost of all natural zones, is part of the Arctic geographic 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 in the Arctic Basin, is mainly covered with glaciers and snow, as well as debris and rubble.

Arctic desert: location, climate and soil

The arctic climate presupposes long, harsh winters and short cold summer without transient seasons and with frosty weathering. In summer, the air temperature barely reaches 0 ° C, it often rains and snows, the sky is covered 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 due to 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 Arctic desert zone have fundamental differences from representatives of the fauna living in continental latitudes - they are much easier to adapt to survival 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 initial stage development and is carried out in a lean layer, which is also characterized by the accumulation of manganese and iron oxides. On the fragments of various rocks, characteristic ferruginous-manganese films are formed, which determine the color of the polar-desert soil, while saline soils are formed in coastal areas.

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

Arctic desert vegetation

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 is very few representatives of flora and fauna.

The territory of the Arctic desert is devoid of shrubs and trees, there are only isolated and small areas with lichens and mosses of rocks, as well as various algae of stony ground. These small islands of vegetation resemble an oasis among endless expanses of snow and ice. The only representatives of herbaceous vegetation are sedges and grasses, and flowering plants are saxifrage, polar poppy, alpine foxtail, buttercup, croup, bluegrass and arctic pike.

Fauna of the arctic desert

The terrestrial fauna of the northern edge is relatively poor due to very sparse vegetation. Birds and some mammals are almost the only representatives of the fauna of the ice deserts.

Among birds, the most common:

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 becomes higher, birds from taiga, tundra and continental latitudes arrive in the Arctic, therefore black geese, white-tailed sandpipers, white geese, brown-winged plovers, tie-backs, black-footed buzzards and black-footed buzzards periodically appear near the shores of the Arctic Ocean ... With the onset of cold seasons, the above species of birds return to the warmer regions of more southern latitudes.

Among the animals can be distinguished the following representatives:

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

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

Adapting animals to the arctic climate

All of the above animals forced to adapt to live in such harsh conditions, so they have unique adaptive characteristics. 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 save themselves from frost thanks to their warm and thick fur, loose plumage helps birds, and for seals, their fat layer is saving them.

An additional rescue of the animal world from the harsh Arctic climate is due to the characteristic color acquired immediately before 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 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 entire family.

Interesting inhabitants of the icy depths of the Arctic

), the prevailing landscape of the northernmost (arctic) natural land area. Characteristic in the main. for coastal areas. Snow and ice cover these territories all year round... The areas of glaciers are very large - up to several tens of thousands of square kilometers. Sometimes they cover more than 80% of the North Islands. The Arctic Ocean (for example, on Franz Josef Land). In places they go down to the ocean, and huge debris break off from them - icebergs... The climate is harsh and cold. Long, severe winters give way to short (sometimes less than 2 weeks) cold summers. Wed the temperature of the coldest month is from –12 ° C in Svalbard to –38 ° C in northern Greenland; temperature of the warmest month 5 ° C. The amount of precipitation will be approx. 300 mm per year, mainly in the form of snow, which strong winds blown away into depressions in the relief, exposing lifeless rocks. Life in icy deserts is practically non-existent. Occasionally in the summer, multicolored colonies of microscopic algae develop on the melting snow.

Geography. Modern illustrated encyclopedia. - M .: Rosman. Edited by prof. A.P. Gorkina. 2006 .

See what "ice desert" is in other dictionaries:

Noun, f., Uptr. often Morphology: (no) what? desert, what? desert, (see) what? desert than? desert, about what? about the desert; pl. what? desert, (no) what? deserts, what? deserts, (see) what? desert than? deserts, about what? about deserts 1. Desert ... Dictionary Dmitrieva

desert- I pu / freeze and; f .; see deserts II are empty / nya and; pl. genus. you / ny; f. see also. desert 1) a) A vast arid area with little precipitation, sharp fluctuations in air and soil, and sparse vegetation ... Dictionary of many expressions

DESERT, and, wives. 1. A large, unpopulated space, devoid of vegetation or with sparse vegetation. Anhydrous p. Ledyanaya, snow p. (Re: about large areas of ice, snow). 2. Deserted or sparsely populated area ... ... Ozhegov's Explanatory Dictionary

AND; pl. genus. tyn; f. 1. A vast arid area with little rainfall, sharp fluctuations in air and soil, and sparse vegetation. Boundless, sultry, red-hot, scorched p. Solonchakovaya p. P. Sahara. P. Karakum. Deserts ... ... encyclopedic Dictionary

- (polar desert, ice desert), a kind of desert (see DESERT) with extremely sparse sparse vegetation among the snows and glaciers of the Arctic and Antarctic belts of the Earth. Distributed over most of Greenland (see GREENLAND) ... encyclopedic Dictionary

The same as the ice desert. Geography. Modern illustrated encyclopedia. M .: Rosman. Edited by prof. A.P. Gorkin. 2006 ... Geographical encyclopedia

Marked in gray is the Arctic Desert ("Arktos" in translation from the Greek bear) is a natural zone, part of the Arctic geographic zone, the Arctic Ocean basin. This is ... Wikipedia

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http: //www..jpg "align = left> The Arctic Desert is part of the Arctic geographic zone, located in the high latitudes of the Arctic. The Arctic Desert Zone, the northernmost of the natural zones, is located in the high latitudes of the Arctic. Its southern border is located at about 71 parallels (Wrangel Island) The Arctic desert zone extends to approximately 81 ° 45 "N. sh. (islands of the Franz Josef Land archipelago). The Arctic Desert Zone includes all islands in the Arctic Basin: this is the island of Greenland,northern part of the Canadian archipelago,Svalbard archipelago, islands of Franz Josef Land archipelago, Severnaya Zemlya, Novaya Zemlya, New Siberian Islandsand a narrow strip along the coast of the Arctic Ocean within the Yamal, Gydansky, Taimyr, Chukotsky peninsulas). These spaces are covered with glaciers, snow, rubble and debris.

Arctic Desert Climate

http: //www..ru) .jpg "align = right> The climate is arctic, with long and harsh winters, summers are short and cold. There are no transitional seasons in the Arctic desert. During the polar night it is winter, and during the polar day - Summer The polar night lasts 98 days at 75 ° N lat., 127 days - at 80 ° N lat. Average winter temperatures are -10 to -35 ° C, dropping to -60 ° C. Frost weathering is very intense.

The air temperature in summer is slightly above 0 ° С. The sky is often covered with gray clouds it's raining(often with snow), due to the strong evaporation of water from the ocean surface, dense fogs are formed.

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. The wind changes to the north and winter comes overnight.

The Arctic climate is formed not only in connection with low temperatures high latitudes, but also due to the reflection of heat from snow and ice crust. Ice and snow cover lasts about 300 days a year.

Annual amount atmospheric precipitation up to 400 mm. The soils are saturated with snow and barely thawed ice.

Vegetation cover

http: //www..jpg "align = left> The main difference between the desert and the tundra is that it is possible to live in the tundra, feeding on its gifts, but it is impossible to do it in the Arctic desert. That is why there was no indigenous population 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 bushes. There are small isolated areas with lichen crust on rocks, mosses, various algae on rocky soils and herbaceous vegetation - sedges and grasses. In the conditions of the Arctic desert, there are some types of flowering plants: polar poppy, crumble, stellate, alpine foxtail, arctic pike, bluegrass, buttercup, saxifrage, etc. These islands of vegetation look like oases among endless ice and snow.

The soils are shallow, with an insular distribution, mainly under vegetation. Spaces free from glaciers are bound by permafrost, the thawing depth does not exceed 30-40 cm even under polar day conditions. The processes of soil formation 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. Ferruginous-manganese films are formed on the rock fragments, which determines the brown color of the polar desert soils. In coastal areas saline by the sea, polar desert saline soils are formed.

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

Animal world

http: //www..jpg "align = right> Due to the sparse vegetation, the fauna of the Arctic deserts is relatively poor. Terrestrial fauna is poor: arctic wolf, arctic fox, lemming, New Zealand deer, in Greenland - a musk ox. On the coast you can find pinnipeds: walruses and seals.

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

http: //www..jpg "align = left> The most numerous inhabitants of the harsh northern region are birds. These are guillemots, puffins, eiders, rose gulls, snowy owls, etc. Seabirds nest on the rocky shores in summer, forming“ bird colonies ” The largest and most diverse seabird colony in the Arctic nests on Rubini Rock, located in the ice-free Tikhaya Bay off Hooker Island (FFI), with up to 18,000 guillemots, guillemots, kittiwakes and other seabirds.

The Antarctic Desert is the largest and coldest on Earth, characterized by large temperature drops 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 associate with heat, endless expanses of sand and small shrubs. However, there are also cold species on Earth - 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 the amount of precipitation, the objects we are considering resemble the southern hot ones, such as the Sahara, therefore 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 (Antarctic), belonging to the Arctic and Antarctic, respectively. climatic zones... They consist of glaciers and stones, 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 ice 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 shores 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 around it. There is also the Antarctic Peninsula, which juts into the depths of the ocean of the same name. On the territory of Antarctica lie dividing the continent into 2 parts: western and eastern.

The western half is located on the Antarctic Platform and is a mountainous area with a height of almost 5 km. In this part there are volcanoes, one of which - Erebus - active, is located on an island in the Ross Sea. There are oases in the coastal areas that are free of ice. These small plains and mountain peaks, called nunataks, have an area of 40 thousand square meters, located on the Pacific coast. There are lakes and rivers on the mainland that only appear in summer time... 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.

Mineral resources located in the bowels of the continent: ore of ferrous and non-ferrous metals, mica, graphite, coal, there is information about the reserves of uranium, gold and diamonds. According to the assumptions of scientists-geologists, there are deposits of oil and gas, however, due to the harsh climate, mining is not possible.

Antarctic deserts: climate

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

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 is due to natural phenomenon called "albedo" - the reflection of heat from the surface of the ice. 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, it consists only of snow. This is due to the extreme cold, which dries moisture, which makes the Antarctic desert the driest place on the planet.

The climate here is different: in the center of the continent there is less precipitation (50 mm), 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 accounts for 90% of the world's total fresh water supply.

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

In the direction from the center of the mainland to the coast, the ice shelf constantly moves, in summer months parts of the glaciers break off, forming icebergs that drift in the ocean.

Mainland population

Antarctica does not have a permanently resident population; 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 research scientists living at scientific stations increases to 4 thousand people in the summer, and only 1 thousand in the winter. According to historical data, the first settlers here were American, Norwegian and British whalers who lived on South Georgia, but with 1966 Whale hunting is banned.

The entire territory of the Antarctic Desert is an 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 islands;
oases located near the coast;
zone of nunataks (mountains near the station "Mirny", mountainous regions in Victoria Land, etc.);
ice sheet zone.

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

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

Vegetable world

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

On the territory of the peninsula and nearby islands, flowering plants were found, and in fresh water blue-green algae live in the oases, which form a crust and cover the bottom of water bodies.

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

Found only 2 species of flowering plants:

Colobantus quito related to This is a pillow-shaped herb, decorated with small flowers of white or light yellow shades, about 5 cm in size.
Antarctic meadow of cereals. 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 water-dwelling.

There are no flying insects, because because of the strong cold wind, they cannot rise into the air. However, small ticks, as well as wingless flies and springtails, are found in oases. Only in this area lives the wingless midge, which is the largest land animal of the Antarctic desert - it is 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.

Antarctica animals

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

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

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

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

The ecosystem of Antarctica and its conservation

The continental ice deserts and cold ocean waters that wash over Antarctica are an ecosystem inhabited by living organisms that have existed here for thousands of years. The main food of animals is phytoplankton.

As a result of warming, glaciers and snow masses in Antarctica are gradually receding, moving closer to the coast. The ice shelves are gradually thawing, the soil is gradually exposed, which contributes to the creation of a more favorable environment for plant settlement. However, the emergence of non-native plant species is not at all welcome on the continent.

The ecosystem of Antarctica and the Antarctic desert needs protection from the appearance of "alien" species of life, so every scientist or tourist who comes here undergoes mandatory processing. In the process, parts of plants or spores are washed off and destroyed.

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

Arctic deserts (polar desert, ice desert), a type of desert with extremely sparse sparse vegetation among the snows and glaciers of the Arctic and Antarctic belts of the Earth. Distributed in 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.
The Arctic desert is home to small isolated areas with mainly crustaceans and lichens and herbaceous vegetation. They look like a kind of oases among 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 vegetation spots on the islands of the Arctic Ocean and on a narrow strip along the Asian coast of the mainland. Soil processes are poorly developed, and the soil profile is practically not pronounced. Rare mosses and lichens practically do not provide "material" for the formation of humus, their humus horizon is rarely thicker than 1 cm. Permafrost has a great influence on the formation of Arctic soils, which thaws in a short summer period (1–2 months) by no more than 0, 5 m. Due to insufficient moisture in the Arctic soils, there is no gleying, the soils have a neutral acid reaction, sometimes carbonate or even saline. In some places, under the spots of algae, specific "film soils" are distinguished with subtle signs of soil formation

Usually, Arctic soils consist of a thin (1-3 cm) organogenic horizon and a mineral mass poorly differentiated into horizons, underlain by a permafrost layer at a depth of 40-50 cm. Little or no gelling. The presence of carbonates or readily soluble salts is possible. Arctic soils are common on the islands of the Arctic Ocean.

Humus in the upper horizons usually contains an insignificant amount (1-2%), but sometimes reaches large values (up to 6%). Its fall with depth is very sharp. The reaction of soils is neutral (pHH2O 6.8-7.4). The amount of exchangeable 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 quantities.

Arctic soils can be divided into two subtypes: 1) arctic desert and 2) arctic typical humus. The current level of knowledge of these soils makes it possible to distinguish two genera within the first subtype: a) saturated and b) carbonate and saline.
Arctic desert calcareous and saline soils are characteristic of the superrarid (precipitation less than 100 mm) and cold parts of the Arctic and the oases of Antarctica. American scientist J. Tedrow calls these soils polar desert. They are found in northern 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.

Most characteristic features arctic soils should be considered the following:

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

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

3) incompleteness and undifferentiation of the soil profile due to the low intensity of 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 permafrost layer 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 drying out in summer lead to cracking of the soil cover. In most of the Arctic, there are almost no formed soils, but only coarse detrital material in the form of placers.

Antarctic and arctic desert: soil, soil characteristics and features

Lowlands and their fine earthy 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 composition and vegetation. Scientific quote: "the main specific feature of the Arctic soils is that they are like a" complex "of soils with a normally developed profile under plant sod and with a reduced profile under algal soil films" gives full description 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 geographic zone, located in the high latitudes of the Arctic. The Arctic Desert Zone - the northernmost of the natural zones - is located in the high latitudes of the Arctic. Its southern border is approximately 71 parallel (Wrangel Island). The zone of arctic deserts extends up to about 81 ° 45 's. sh. (islands of the Franz Josef Land archipelago). The Arctic Desert Zone includes all the islands in the Arctic Basin: the island of Greenland, the northern part of the Canadian archipelago, the Spitsbergen archipelago, the islands of the Franz Josef Land archipelago, Severnaya Zemlya, Novaya Zemlya, the New Siberian Islands and a narrow strip along the coast of the Arctic Ocean within the Yamal Peninsulas, Gydansky, Taimyr, Chukotsky). These spaces are covered with glaciers, snow, rubble and debris.

Arctic Desert Climate

The climate is arctic, with long and harsh winters; summers are short and cold. Transition seasons in Arctic 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 - at 80 ° N. 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 ° С. The sky is often covered with gray clouds, it is raining (often with snow), thick fogs are formed due to the strong evaporation of water from the ocean surface.

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.

Arctic desert soils

The wind changes to the north and winter comes overnight.

The Arctic climate is shaped not only by the low temperatures of high latitudes, but also by the reflection of heat from snow and ice crust. Ice and snow cover lasts about 300 days a year.

The annual amount of precipitation is up to 400 mm. The 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, feeding on its gifts, but in the Arctic desert this is impossible. That is why there was no indigenous population 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 bushes. There are small isolated areas with crusty 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, crumble, stellate, alpine foxtail, arctic pike, bluegrass, buttercup, saxifrage, etc. These islands of vegetation look like oases among endless ice and snow.

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, New Zealand deer, in Greenland - a musk ox. On the coast you can find pinnipeds: walruses and seals.

The most numerous inhabitants of the harsh northern region are birds. These are guillemots, puffins, eiders, rose gulls, snowy owls, etc. Seabirds nest on rocky shores in summer, forming “bird colonies”. The largest and most diverse seabird colony in the Arctic nests on Rubini Rock, located in the ice-free Tikhaya Bay off Hooker Island (FFI). The bird colony on this rock numbers up to 18 thousand guillemots, guillemots, kittiwakes and other seabirds.

What is the soil 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 ° С, average annual temperatures below -14 ° С to -18 ° С) under a lichen film and pods of mosses and flowering plants (higher plants occupy less than 25% of the surface or none at all) and are characterized by an underdeveloped shallow soil profile of the A-C type.

The type of Arctic soils was introduced into the taxonomy of soils in Russia 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 Antarctica, the vegetation cover is represented only by bale lichens and mosses; in cracks in rocks and on a fine earthy substrate, 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, a large role belongs to mosses, lichens, different types algae. The vegetation cover is confined to frost cracks, drying cracks and depressions of another genesis. There is practically no vegetation above 100 m above sea level. The main types of distribution of plant sod are curtain-pillow and polygonal-mesh. Bare ground covers 70 to 95%.

Soil thaws 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 highly waterlogged due to stagnant moisture formed during thawing. soil ice over the frozen horizon; in summer, the soil from the surface dries up and cracks due to round-the-clock insolation and strong winds.

Differentiation of Arctic soils by gross chemical composition very weak... It is possible to note only a slight accumulation of sesquioxides in the upper part of the profile and a fairly high background of the iron content, which is associated with the cryogenic pulling of iron, which is mobilized under the conditions of a seasonal change in aerobic and anaerobic conditions. Cryogenic pulling of iron in the soils of arctic deserts is better expressed than in any other permafrost soils.

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

The ratio of carbon of humic acids to carbon of fulvic acids is of the order of 0.4-0.5, often even less.

The generalized materials of I.S.Mikhailov indicate that the Arctic soils have, as a rule, a weakly 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 with almost complete saturation with bases (96-99%). Sometimes there is a weak removal of calcium, magnesium and sodium, but it is replenished by the impulse of sea salts. Typical Arctic soils, as a rule, do not contain free carbonates, except for those cases 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 makes it possible to distinguish two genera within the first subtype: a) saturated and b) carbonate and saline.

Arctic desert calcareous and saline soils are typical for the superrarid (precipitation less than 100 mm) and cold parts of the Arctic and the oases of Antarctica. 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 weakly acidic or neutral reaction, have slightly larger reserves of humus than soils of the first subtype, are formed under soddy areas of landfills, they do not have salt accumulations. This subtype of arctic soils prevails 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) shortened profile due to low intensity of soil-forming processes and shallow seasonal thawing; 3) incomplete and undifferentiated soil profile due to the low intensity of 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.

The territories of the Arctic and Antarctic lie outside the limits of human agricultural activities... In the Arctic, these areas can only be used as hunting grounds and reserves for the preservation and maintenance of numbers. rare species animals (polar bear, musk ox, white Canadian 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 even at this time. Permafrost (cryogenic) processes predominate - cracking, freezing, debate, due to which fracture polygons are formed on loose rocks and stone hills, rings, stripes on stone rocks. Physical weathering dominates, leading to the formation of a coarse-detrital, weakly biogenic, weakly leached weathering crust. Geochemical and biochemical weathering is very slow, and is absent from late August to early July. The soil cover on the watersheds is focal, and not continuous - some areas of the Arctic soils against the background of soil films under algae spots (1 ... 2 cm thick).

The soil cover is formed only in areas with fine earth, fragmentarily under vegetation, which develops selectively in accordance with the conditions of the relief, exposure, moisture, and the nature of the 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. The 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 low input of organic residues (0.6 t / ha), the absence of an acidic litter horizon Ao, an illuvial horizon, and the presence of strong stony on the surface. The soil horizons contain a lot of skeletal material. They lack gleying due to low moisture content and significant aeration. These soils are characterized by cryogenic accumulation of iron compounds, little or no movement of substances along the profile, high saturation (up to 90%) with bases, weakly acidic, neutral, sometimes slightly alkaline reaction.

In the Arctic zone, a type is distinguished - arctic desert soils, which includes two subtypes: desert-arctic and arctic typical soils.

Desert-arctic soils are widespread in the northern part of the arctic zone in leveled areas, more often with sandy loam and sandy-gravelly deposits under moss-lichen clumps with single specimens of flowering plants. Large areas are under sand, rubble, eluvial and deluvial deposits and stone mounds. Their surface is broken up 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 color, sandy loam or light loamy, with a fragile granular structure, uneven or noticeable transition to the next horizon; А1С - transitional horizon 20 ... 40 cm thick, brown or yellow-brown color, less often spotty, sandy loam, fragile-fine lumpy or structureless, transition along the thawing boundary; C - frozen soil-forming rock, light brown, sandy loam, dense, gravelly.

The A1 horizon contains only 1 ... 2% of humus. The reaction of soils is neutral and slightly alkaline (pH 6.8 ... 7.4). The amount 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). In early summer, when snows and glaciers melt, the soils become waterlogged, and in summer they dry out quickly due to round-the-clock insolation and strong winds.

In depressions with stagnant waters and in areas flooded with thawed running waters snowfields and glaciers, under the moss-grass vegetation, there are boggy arctic soils. In areas with stagnant waters, gleyed horizons with a heavy granulometric composition are clearly expressed, while in areas flooded by running waters, genetic horizons differ little and there is no gleying.

In the mouths of the rivers, marching salt marshes are developed, and biogenic accumulations are at the bird colonies.

Typical Arctic soils are formed on high plateaus, upland watershed heights, abrasion-accumulative sea terraces, mainly in the south of the Arctic zone, under moss-forb-cereal vegetation of frost cracks and drying cracks.

The soil profile is shallow - 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, fragile granular-lumpy structure, porous, with cracks, compacted, in the middle of the polygon the horizon wedges out; the transition is uneven and noticeable; A1C - transitional horizon (30 ... 40 cm) from light-brown to brown, loamy, lumpy-nutty, dense, fractured, transition along the thawing boundary; C - frozen soil-forming rock, light brown, often with rock debris.

The soils have discrete humus horizons. The profile is predominantly uneven in thickness of the A1 horizon, often with humus pockets. In horizon A1, the amount of humus sometimes reaches 4 ... 8% and gradually decreases down the profile. Fulvic acids dominate in humus (Cgc: Cfc = 0.3 ... 0.5). Inactive fulvates and calcium humates predominate, the content of non-hydrolyzable residue is significant. There are few silty particles; they consist mainly of hydromicas 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.