When you hear the word "desert", what immediately comes to mind? For most people, the desert evokes images of endless sandy expanses, high temperatures and bushy vegetation. To some extent, this representation is accurate. Many deserts of the world are characterized by large amounts of sand and high temperatures (at least during daylight hours).
However, there are arctic deserts that are radically different from the rest of the deserts. There is no sand here, and temperatures are often far from hot, but on the contrary sub-zero.
If you know anything about the Arctic, you are probably wondering who came up with the idea of calling this region a desert. After all, the Arctic has the Arctic Ocean. However, Arctic temperatures are so low that the ocean is almost always covered in ice. Severe frost also means that the air is unable to retain moisture. Thus, the air is dry, like in a classic desert.
Another strong argument is the insignificant amount of precipitation in the form of rain or snow. In fact, the Arctic receives roughly the same amount of rainfall as the Sahara. All of the above factors led to the emergence of the concept of "arctic or cold desert".
Natural conditions of the arctic desert zone
To determine the natural conditions of the Arctic desert, below is a brief description and a table of the main factors ( geographical position, relief, soil, climate, Natural resources, flora and fauna), which have an impact on the life of the people of this natural area.
Geographical position
Arctic desert on the map of the main natural zones of the world
Legend: - Antarctic Desert.
The natural zone of the arctic desert is located above 75 ° north latitude and is adjacent to the North Pole of the Earth. It covers total area more than 100 thousand km². The Arctic desert covers Greenland, the North Pole and several islands, many of which are inhabited by humans and animals.
Relief
The relief of the Arctic desert consists of various physical features: mountains, glaciers and flat areas.
The mountains: the arctic desert contains mountainous regions where a cold and dry climate prevails. In appearance, some of the mountains in the region resemble those in Central America.
Glaciers: because of the extremely low temperatures, the arctic desert is replete with numerous glaciers of various shapes and sizes.
Flat areas: make up the bulk of the region's territory and have a distinct patterned texture, which is the result of cycles of melting and freezing of water.
If you've watched Game of Thrones, the Lands Beyond the Wall gives you an idea of what an Arctic desert looks like. These scenes were filmed in Iceland, which is not officially considered part of the Arctic desert, but bears a physical resemblance to it.
Soil
In the main part of the natural zone of the Arctic desert, the soils remain frozen for most of the year. Permafrost reaches 600-1000 m in depth, and makes it difficult to drain water. In summer, the surface of the Arctic desert is covered with lakes of melt water from the upper soil layer. Crushed stone and rocks, due to the movement of glaciers, are scattered throughout the natural zone.
The soil horizon of the arctic deserts is very thin, poor in nutrients, and also contains a lot of sand. In warmer regions, there are soil types containing little organic matter, and capable of supporting the growth of small shrubs, algae, fungi and mosses. Brown soils are one of these types of soils.
Climate
The climate of the natural zone of the Arctic desert is characterized by a long, very cold winter and short cool summers. During colder months (usually December to January), temperatures can drop to -50 ° C. During warmer months (usually July), temperatures can rise to + 10 ° C. However, for many months, average temperatures range from -20 ° to 0 ° C.
The Arctic desert receives very little rainfall. Average annual rainfall is below 250 mm. Precipitation, as a rule, falls in the form of snow and light drizzle, more often in the warm season.
During the summer months, the sun does not set in the Arctic desert at all. In fact, for 60 days, the sun is above the horizon around the clock.
Animals and plants
A total of about 700 plant species and about 120 animal species are found in the natural zone of the arctic deserts. Flora and fauna have adapted to survive and even thrive in such extreme conditions. Plants were able to adapt to nutrient-poor soils, low temperatures environment and low rainfall. usually have a thick layer of fat and a thick coat for protection from the cold. They reproduce during the period short summer and often hibernate or migrate in winter. Birds usually fly south during the cold winter months.
Only about 5% of the natural zone of the Arctic desert has a vegetation cover. Although this is not surprising given the status of the desert. Most of plant life consists of the following plants: lichens, mosses and algae, which can survive in the extreme conditions of the Arctic.
Every year (especially in the warm season), some types of low (from 5 to 100 cm) shrubs bloom. They typically include sedges, liverworts, grasses, and various types of flowers.
Animal life in the Arctic desert is very diverse. There are many mammals, birds, fish and insects. All of these animals are adapted to extremely low temperatures. Here are some examples of animals in the natural zone of arctic deserts:
- Mammals: Arctic foxes, polar bears, wolves, squirrels, hares, arctic voles, lemmings, reindeer, seals, walruses and whales.
- Birds: crows, falcons, loons, sandpipers, snipe, terns and various types of gulls. Most of these birds are migratory (i.e. spend only part of their life cycle in the arctic desert).
- Fishes: trout, salmon, flounder and cod.
- Insects:
Natural resources
The Arctic includes significant reserves (oil, gas, minerals, fresh water and commercial fish species). also in last years tourist interest in this region has grown significantly, which also provides additional economic benefits.
The pristine and endless deserts of the Arctic play an important role in the conservation of biodiversity due to the growing presence of humans, as well as the fragmentation of vital habitats. Arctic deserts especially susceptible to depletion of the soil cover and disturbance of the habitat of rare animals characteristic of the region. The Arctic also contains 20% of the world's fresh water.
Table of the natural zone of arctic deserts
| Geographical position | Terrain and soil |
Climate | Flora and fauna | Natural resources |
| Arctic regions located above 75 ° north latitude and receiving low precipitation (less than 250 mm per year). | The relief is mostly flat, but sometimes mountainous areas are found. The soils are very poor in organic nutrients and remain frozen for most of the year. |
The climate is dry and cold. Average temperatures range from 0 ° to -20 ° C. In winter, the air temperature can drop below -50 ° C, and in summer it can rise to + 10 ° C. | Animals
mammals: polar foxes, polar bears, wolf, reindeer, hares, squirrels, voles, lemmings, walruses, seals and whales; birds: crows, falcons, loons, sandpipers, snipe, terns and gulls; fishes: trout, salmon, flounder and cod; insects: grasshoppers, arctic bumblebees, mosquitoes, moths, midges and flies. Plants shrubs, grasses, lichens, mosses and algae. |
oil, gas, minerals, fresh water, commercial fish. |
Peoples and cultures
The most numerous inhabitants of the arctic deserts are the Inuit. If the word "Inuit" is not clear to you, then most likely you have heard about the Eskimos.
The Inuit have adapted their lives to the harsh conditions of the Arctic desert. As a rule, in the Arctic there is practically no building materials... Eskimos build snow huts called Igloos. In the summer, when Igloos are hidden, they live in tents made from animal skins and bones.
Considering extreme conditions deserts, Inuit do not grow crops and vegetable crops... They feed mainly on meat and fish. Thus, their main food sources are fishing, as well as hunting for seals, walruses and whales.
To get around, Inuit usually use dog sleds. The sled is made of hides and bones. They are pulled by strong, hardy, sled dogs (husky, Malmouth, Samoyed). When moving on water, they use kayaks or umiaki. Kayaks are small boats suitable for carrying one or two people. Umiakas are large enough to carry several people, dogs, and supplies.
Eskimo communities are found in various parts of the Arctic desert and. In Greenland, they are known as Iñupiat or Yupik. In Russia they are called Eskimos. Regardless of name or geographic location, Inuit speak the same Inuktitut language. They also have similar cultural traditions and everyday life.
Meaning for a person
In recent years, the Arctic desert has experienced an increase in tourism. Visitors cold desert come here for the unique ecosystem and mesmerizing snowy landscapes. Lakes, rivers, streams and mountains provide additional leisure activities for tourists from all over the world. Some recreational activities include sea cruises, boating, sport fishing, mountain climbing, hunting excursions, rafting, hiking, dog sledding, skiing, snowshoeing, and more. The non-setting sun during the Arctic summer is another reason for the interest of tourists who visit the Arctic desert for this surreal phenomenon. Visitors also experience Inuit culture and life by visiting their settlements. The Arctic desert, being the polar region of the planet, plays a key role in regulating the Earth's climate.
Environmental threats
The population of people in the natural zone of the Arctic desert and the surrounding areas is rather low. The most pronounced threat comes from the exploration of mineral deposits and their extraction. Global warming also has negative impact on the arctic desert environment, upsetting the delicate balance of this ecosystem. As the planet's temperature rises, it heats up and melts, as a result of which carbon is released from the soil into the atmosphere, which accelerates the processes of climate change. Because of global warming, they are polar ice, which contributes to sea level rise and increases the threat of flooding of the world's coastal regions. Melting ice caps are also threatening polar bears. They need ice for hunting, and melting ice shortens and divides their hunting grounds into fragments. In addition, orphaned cubs have even lower survival rates because they are left to fend for themselves.
Conservation of arctic deserts
To protect the natural zone of the Arctic deserts, it is necessary to provide assistance, cooperation, coordination and interaction between states with the participation of communities of the indigenous peoples of the Arctic on sustainable development and environmental protection of the region.
The main goals of protecting the Arctic deserts include:
- Conservation of the rich biodiversity of the region;
- Sustainable use of renewable natural resources;
- Reducing pollution and wasteful consumption.
To achieve the set goals, it is necessary to focus international attention on the following problematic aspects:
- Marine environment;
- Fresh water;
- Biodiversity;
- Changing of the climate;
- Pollution;
- Oil and gas.
Only political will and interaction between states can give positive result in the struggle for the preservation of both the natural zone of the Arctic desert and the nature of the world as a whole.
Natural zones of Eurasia
Arctic deserts
Tundra and forest-tundra
Taiga zone
Mixed and deciduous forests
Steppe and forest-steppe
Deserts and semi-deserts
Savannah and woodlands
Humid equatorial forests
Mountain areas
1. Arctic deserts
1. Arctic deserts
Geographic center of the image: 73 ° 24'N, 70 ° 38'E
Spectral channels: 1, 4, 7
Instrument: ETM +
Date: August 9, 2001
Source: http://glcf.umiacs.umd.edu/, http://www.iki.rssi.ru
Additional description: The image is synthesized in pseudo colors. The northern part of Bely Island (Yamalo-Nenets Autonomous District, Russia) is presented. Dark blue and blue colors have water bodies - water mirror of the Kara Sea and lakes. Green tones - mosses, lichens, undersized shrubs. Yellow tones - open areas areas with little presence of mosses and lichens. Pink tones - open areas of terrain without vegetation (mainly stones). White color- sand along the coast of the Kara Sea.
2. Tundra and forest-tundra
Spacecraft: Landsat
Spatial resolution (native): 28.5 m
Geographic center of the image: 64 ° 05'N, 69 ° 27'E
Spectral channels: 1, 4, 7
Instrument: ETM +
Date: July 21, 2000
Source: http://glcf.umiacs.umd.edu/, http://www.iki.rssi.ru
Additional description: The image is synthesized in pseudo colors. A section of the northeastern territory of the Nenets Autonomous District (Russia) is presented. Water bodies (lakes, sea, rivers) are displayed in dark blue, almost black, color. Pale green shades - tundra vegetation - low rare shrubs, lichens, mosses, low grasses. Green tones - shrubs, dwarf woody vegetation (dwarf birches and willows), grass. Red-brown, orange and yellowish tones are open areas with a low content of mosses and lichens.
3. Taiga zone
Spacecraft: Landsat
Spatial resolution (native): 28.5 m
Geographic center of the image: 62 ° 31'N, 59 ° 05'E
Spectral channels: 1, 4, 7
Instrument: ETM +
Date: September 12, 2001
Source: http://glcf.umiacs.umd.edu/, http://www.iki.rssi.ru
Additional description: The image is synthesized in pseudo colors. A plot of the territory of the Komi Republic in the middle reaches of the Ilych River is presented. Dark blue (almost black) color - the Ilych river and its tributaries (threadlike structures). Dark green-brown tones - dark coniferous taiga - dense spruce forests with an admixture of fir. Dark green tones - coniferous vegetation- spruce, pine, fir; somewhat lighter - mixed forests. Green shades- also mixed forests, but with a predominance of deciduous species (birch, aspen). Bright green - meadow areas (grasses, shrubs). Yellow shades - rare grasses and shrubs with a low chlorophyll content. Reddish and pink tones - open areas of the terrain, including those with a very rare vegetation cover, rock outcrops of the Ural Mountains.
4. Mixed and deciduous forests
Spacecraft: Landsat
Spatial resolution (native): 28.5 m
Geographic center of the image: 55 ° 46'N, 39 ° 07'E
Spectral channels: 3, 4, 5
Instrument: ETM +
Date and time: July 7, 2001
Source: http://glcf.umiacs.umd.edu/, http://www.iki.rssi.ru
Additional description: The image is synthesized in pseudo colors. Water bodies (rivers, lakes), as well as peat bogs are shown in dark blue and black. Dark green shades - taiga pine massifs. Green and dirty green shades of heterogeneous texture - southern taiga coniferous-deciduous forests (spruce, pine, birch, aspen). Bright green shades - young deciduous forests, shrubs in the field of forest felling (have clear boundaries), meadow vegetation in the floodplains of rivers. Lilac and pinkish shades - open soil. Purple tones - residential areas ( settlements, roads). Reddish shades - depleted peatlands.
5. Steppes and forest-steppes
Spacecraft: Landsat
Spatial resolution (native): 28.5 m
Geographic center of the image: 46 ° 43'N, 39 ° 45'E
Spectral channels: 1, 4, 7
Instrument: ETM +
Date: August 9, 2000
Source: http://glcf.umiacs.umd.edu/, http://www.iki.rssi.ru
Additional description: The image is synthesized in pseudo colors. The site of the territory is presented Krasnodar Territory... Almost all steppe zone plowed up for agricultural land (objects of the correct geometric shape with clear boundaries). The steppe and forest-steppe zones are characterized by a large number of gullies and small rivers. The color of fields without vegetation - dark pink or pink - is due to dark chernozem soils. Light green color - winter crops and herbaceous vegetation of ravines, brownish green color - weak soil cover with vegetation. There are many ponds, the color of the water is black.
6. Deserts and semi-deserts
Spacecraft: Landsat
Spatial resolution (native): 28.5 m
Geographic center of the image: 45 ° 57'N, 69 ° 59'E
Spectral channels: 1, 4, 7
Instrument: ETM +
Date: July 28, 2000
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Climate, natural zones of Eurasia.
Climate.
The climatic features of Eurasia are determined by the enormous size of the continent, a great length from north to south, a variety of dominant air masses, as well as the specific features of the structure of the relief of its surface and the influence of the oceans.
Natural areas.
Arctic deserts ( ice zone), tundra and forest-tundra located in the west of the mainland beyond the Arctic Circle. In Northern Europe, tundra and forest-tundra occupy a narrow strip, which gradually expands as it moves eastward with an increase in the severity and continentality of the climate. Basically, poor low-growing vegetation, poor peat-gley soils and animals adapted to the harsh living conditions.
V temperate large areas are represented by zones coniferous forests(taiga), mixed conifers broadleaf forests, broadleaf forests, forest-steppes and steppes, semi-deserts and deserts.
Coniferous forests stretched from the Atlantic to the Pacific Ocean. Moving from west to east, the continentality of the climate increases. In the Asian part of the zone is widespread permafrost, as a consequence, the composition of the taiga tree species changes. Pine and spruce prevail in the European taiga, fir and Siberian cedar dominate beyond the Urals, and larch in Eastern Siberia. Animal world: sable, ermine, beaver, fox, squirrel, marten, hares, chipmunks, lynxes and wolves, elks, brown honey vedi, capercaillie, black grouse, hazel grouses, crossbills, nutcrackers.
Zone mixed coniferous-deciduous forests changes the taiga zone when moving south. Deciduous litter and grass cover of these forests contribute to the accumulation of a certain amount of organic matter in the soil horizon. Therefore, the podzolic soils of the taiga are replaced by sod-podzolic soils.
Zone broadleaf forests also does not form a continuous strip. In Europe, it stretches from the Atlantic to the Volga. As the continentality of the climate increases, when moving from west to east, beech forests are replaced by oak forests. In the east of the mainland, deciduous forests are mostly cut down.
Forest-steppe and steppe change forest zones when moving south in the inner - central continental sector of the mainland. Here the amount of precipitation decreases sharply and the amplitudes of summer and winter temperatures increase. V forest-steppe the alternation of open spaces with herbaceous vegetation on chernozem soils with areas of deciduous forests is characteristic. Steppe - treeless spaces with dense gramineous herbaceous vegetation and dense root system. In the eastern part of the continent, forest-steppe and steppe have survived in the relief basins of Northern Mongolia, Transbaikalia, and Northeastern China. They are far removed from the ocean, are in a sharp continental climate, weak moisture. Mongolian dry steppes are characterized by sparse grasses and chestnut soils.
Semi-deserts and deserts temperate zone occupy the lowlands of the Middle and inner basins Central Asia north of the Tibetan Plateau. There is very little rainfall, hot, long summers and Cold winter with noticeable frosts.
Zone tropical deserts - the deserts of Arabia, Mesopotamia, the south of the Iranian Highlands and the Indus basin. These deserts are similar in their natural conditions to African ones, since there are wide historical and modern ties between these territories and there are no obstacles to the exchange of species in flora and fauna. The oceanic sectors of the mainland are closed in the south by zones of subtropical (in Europe) and rainforest(in Asia).
Zone stiff-leaved evergreen forests and shrubs on the territory of the Mediterranean is distinguished by its special originality. Here are dry and hot summers, humid and warm winter... Plants are adapted to climatic conditions: waxy coating, thick or dense leathery bark. Many plants produce essential oils. Fertile brown soils are formed in this zone. On the plantations of the zone, olives, citrus fruits, grapes, tobacco, essential oil crops are grown.
Zone monsoon evergreen mixed forests expressed in the Pacific sector of the subtropical belt. There are other climatic conditions here: precipitation falls mainly in summer - during the growing season. The forests are ancient.
Subequatorial belt covers the Indian subcontinent, Indochina and the north of the Philippine Islands. In this belt different conditions humidification. Sub zone equatorial forests stretches along the western coasts of the peninsulas and receives up to 2000 mm of precipitation per year. The forests here are multi-tiered, distinguished by a variety of species composition (palms, ficuses, bamboos). Zonal soils are red-yellow ferralite. Zones seasonally wet monsoon forests, shrub savannas and woodlands presented where the amount of precipitation decreases.
Wet equatorial forests are represented mainly on the islands of Southeast Asia. In terms of climatic conditions, they are similar to forests. equatorial belt other continents. However, the equatorial forests of Asia have a number of specific features... In terms of flora composition, these are the richest forests in the world (over 45 thousand species). Species composition tree species- 5000 species (in Europe - only 200 species).
Altitudinal zonality in the mountains of Eurasia is diverse. The number of altitudinal zones in the mountains always depends on what natural zone is located on the plain at the foot of the mountains; from the height of the mountain system and from the exposure of the slopes. For example, the northern drier slopes of the Himalayas, facing the Tibetan Plateau, do not have forest belts. But on the southern slopes, which are better humidified and heated, there are several forest zones.
Along the shores of the Arctic Ocean, the tundra stretches in a wide strip - an area without a forest with swamps, rivers and streams.
The climate is so harsh that tall trees cannot grow. Long frosty winters lasting 9 months of the year give way to short and cool summers. Due to low temperatures, the ground freezes, in summer only the top layer of the soil has time to thaw, on which mosses, lichens, grasses, small shrubs - blueberries, cloudberries, lingonberries, as well as creeping dwarf willow and dwarf birch grow. Plants have adapted to such a harsh climate: as soon as summer comes, they begin to bloom hastily in order to have time to give fruits and seeds before the onset of cold weather. Ripe seeds wait out a long winter without freezing.
The tundra in the short northern summer is covered with a bright carpet of flowers, variegated moss and dwarf trees. Plants, hidden under the snow for nine months a year, strive to show their full beauty and enjoy the rays of the sun.
Tundra zones, natural zones of the continents, mainly Northern hemisphere(v Southern hemisphere are found in small areas on islands near Antarctica), in the Arctic and subarctic belts... In the Northern Hemisphere, the tundra zone is located between the arctic desert zones in the North, and the forest-tundra in the South. Stretched in a strip 300-500 wide km along the northern coasts of Eurasia and North America.
River in the Tundra.
Climatic conditions
The latitudes in which the Tundra zones are located have a low annual radiation balance. Winter lasts 8-9 month per year, with 60-80 days The polar night lasts, during which there is no radiation heat. In the tundra zone of the European part of Russia average temperature January from - 5 to - 10 ° С, in the North-East of Siberia and Of the Far East frosts were noted down to -50 ° C and below. Snow cover occurs from October to June, its capacity in the European part is 50-70 cm, in Eastern Siberia and Canada 20-40 cm, storms are frequent. Summer is short with long polar days.
Positive temperatures (sometimes up to 10-15 ° C) are noted within 2-3 month., however, frosts are possible on any day of summer. Duration of the growing season 50-100 days... Summer is characterized by high relative humidity, frequent fogs and drizzling rains. Little precipitation falls (150-350 mm per year on the plains, up to 500 mm in the mountains), however, their number almost everywhere exceeds the evaporation rate, which contributes to the development of swamps and the formation of waterlogged soils with bare processes.
Vegetable world
Distinctive features of the Tundra zone are treelessness, the predominance of a sparse moss and lichen cover, strong swampiness, widespread permafrost and the short growing season. The harsh climatic conditions of the Tundra zone determine the impoverishment of the organic world. The vegetation includes only 200-300 species of flowering plants, about 800 species of mosses and lichens.
Plants of the tundra.1. Blueberries.
2. Lingonberry.
3. Black crow.
4. Cloudberry.
5. Loydia is late.
6. Skoroda onion.
7. The prince.
8. Vaginal fluff.
9. Mechelistnaya sedge
10. Dwarf birch.
Most of the tundra zone of the Northern Hemisphere is occupied by subarctic tundras (northern and southern), on its northern outskirts giving way to Arctic tundras, where there are no thickets of bushes, along with mosses, lichens and grasses, arctoalpine shrubs play an important role.
In the East European part of Russia and in Western Siberia the southern Tundras are characterized by large-birch Tundras, with a well-defined layer of dwarf birch with an admixture of willows. Towards the North, the layer of shrubs thinns, they become more squat and, along with mosses, dwarf shrubs and semi-creeping shrubs, sedge acquires a large role in the vegetation cover, and there is an admixture of dryads. In Eastern Siberia, with an increase in the continentality of the climate, large-birch tundras are replaced by small-birch tundras with another species of birch. In Chukotka and Alaska, hummock tundra with cotton grass and sedge dominate, with the participation of hypnum and sphagnum mosses and an admixture of low-growing shrubs, which are decreasing towards the North. The subarctic Tundras of Canada and Greenland are dominated by Tundras dominated by ericoid shrubs. Tundras serve as pastures for deer, hunting grounds, and places for picking berries (cloudberries, blueberries, shiksha).
Forget-me-not. Poppy polar
Animal world
The main occupations of the population are reindeer husbandry, fishing, hunting for fur and sea animals. Because of a large number Water in the tundra willingly spend the summer with various waterfowl - geese, ducks, loons, flying away to the south with the onset of winter. Animals have also adapted to difficult conditions: someone hibernates in winter, someone (for example, a lemming) is awake under the snow, someone leaves the tundra for the winter. Characteristics tundra fauna - extreme poverty associated with the severity of living conditions and the relative youth of the fauna, the presence of endemics, sometimes belonging to independent genera, as well as uniformity, determined by the circular distribution of most species, and the connection of many inhabitants with the sea (birds living in bird colonies, white bear, row of pinnipeds). Birds are characterized by a small number of passerine species, especially granivores, an abundance of waders and waterfowl, of which the white-fronted and black geese and the bean goose are especially abundant. white goose and snowy owl, snow buzzard and Lapland plantain, Upland buzzard, peregrine falcon is characteristic, white (living in the taiga) and tundra (found in the mountains) partridges, horned lark (found not only in the tundra, but also in the treeless highlands and steppes) are widespread ). There are no reptiles. From the amphibians from the south some frogs enter. Of the fish, salmonids predominate; Dallia lives in Chukotka and Alaska. Diptera predominate among insects (mosquitoes are abundant). Relatively numerous: Hymenoptera (especially sawflies, as well as bumblebees associated in their distribution with legumes), beetles, springtails, butterflies. Most of the vertebrate species leave the tundra for the winter (birds fly away, mammals migrate away), only a few, for example lemmings, stay awake under the snow. Permafrost and associated swampiness do not favor the existence of hibernating forms and burrowers.
Among the insectivores of the Tundra fauna, only the shrews are found; from rodents - species of common and ungulate lemmings are endemic, mainly in southern parts some voles are found on the tundra (for example, the root vole, Middendorf vole, red, red-gray, and some others); from the lagomorphs - the white hare; of the predatory fox, which migrates to the forest-tundra for the winter, partly to the northern taiga; ermine and weasel are widespread, foxes, wolves are found, polar bears come from the North and brown ones from the South; of ungulates, the musk ox is widespread, and the reindeer is characteristic.
Reindeer
Reindeer is a symbol of the tundra. It - sole representative ungulates, able to exist in the open northern tundra and on the islands of the Arctic Ocean. Big horns is present in both males and females. It feeds mainly on lichens (lichen), grass, buds and shrub shoots. In winter, it gets food from under the snow, breaking it with hooves.
Body length of males up to 220 cm, height at withers up to 140 cm, weigh up to 220 kg; females are smaller. Hairline in winter it is dense and long, with a strongly developed undercoat, in summer it is shorter and thinner. The color in summer is monochromatic, brownish or grayish-brown, in winter it is lighter, sometimes almost white. Horns are developed in males and females; in males they are larger. The head is small; bow covered with hair. The ears are short, with a rounded apex. The toes are able to move wide apart; the middle hooves are wide and flat, the lateral hooves are long (in a standing animal they touch the ground); as a result, reindeer hooves have a relatively large support area, which facilitates movement in deep snow and swampy places.
Reindeer is widespread in Europe, Asia and North America; inhabits polar islands, tundra, plain and mountain taiga. Herd polygamous animal. Reindeer commits seasonal migrations moving on winter months to places rich in reindeer pastures, sometimes located many hundreds of kilometers from summer habitats (from the tundra to the forest-tundra and the northern part of the taiga).
The reindeer herd is divided into several groups. In each such group there is one main male, who in fights proves his superiority to other males. These battles can last up to 30 minutes. Battles between male reindeer are not as aggressive as among other species of reindeer. They are usually of a ritual nature. The main weapon in such battles is horns. The antlers of reindeer are the largest in terms of body weight compared to the antlers of other deer. The horns have a complex structure. Therein lies the danger of fights between males. More often than in other species of deer, the antlers of reindeer are intertwined with each other, the animals cannot free themselves and die.
In May - June, females give birth to 1 fawn, less often 2; feed them milk 4-5 month Puberty at the 2nd year of life. Soon after the rut, the males shed their horns. New horns develop from April to August. Females shed their horns after calving; development of new ones ends in September. Molt once a year. Reindeer is a cautious, empathetic animal with good developed sense of smell... Swims freely across rivers and lakes.
TOPIC 2. EURASIA
LESSON 51. NATURAL ZONES OF EURASIA. ARCTIC DESERT. TUNDRA AND LESOTUNDRA. FORESTS OF THE MODERATE BELT. FOREST STEPPES AND STEPPES
Target:
· To form knowledge about the natural zones of Eurasia; to contribute to the understanding of the patterns of their distribution on the territory of the mainland; to improve practical skills and abilities to characterize the natural zones of the continent with thematic maps of the atlas;
Develop the ability to independently plan ways to achieve educational tasks, organize joint activities with peers, work in a group, find common decision; develop competencies in the use of ICT technologies;
· Foster the desire for self-organization, respect for the opinions of others.
Equipment: physical map of Eurasia, map of natural zones of the world, map climatic zones world, textbooks, atlases, computer, multimedia projector, student multimedia presentations.
Lesson type: combined.
Expected results: students will be able to characterize the patterns of placement of natural zones in Eurasia; identify features natural complexes Eurasia with thematic atlas maps and other sources of geographic knowledge.
DURING THE CLASSES
I. ORGANIZATIONAL MOMENT
II. UPDATING REFERENCE KNOWLEDGE AND SKILLS
Reception "Blitzopros"
· What is called a natural area?
· How is the change of natural zones in the plains? in the mountains?
III. MOTIVATION OF LEARNING AND COGNITIVE ACTIVITIES
Reception "Practicality of the theory"
Make an assumption about the features of the natural zones of Eurasia based on knowledge of its geographic location, climate, relief.
(Student responses.)
Indeed, the map of the natural zones of the mainland resembles a bright spotted carpet. On one of the studied continents, there is no such diversity of soils, plants and animals that is observed in Eurasia. On one of the studied continents, areas of altitudinal zonation do not occupy such large areas.
In order to identify and explain the patterns of distribution of natural zones of Eurasia and to study them natural ingredients, you will need knowledge of the geographical position, climate and relief of the continent, the ability to work with thematic maps of the atlas. "
IV. STUDYING NEW MATERIAL
1. Study of the patterns of location of natural zones
Working with the map " Natural areas Eurasia "
Tasks
1) Using a map of natural zones from north to south, list the natural zones of Europe along the meridian 30 ° east. d. and Asia along the meridian 100 ° sk. e. What differences do you notice?
2) Which natural zones of Eurasia stretch as a continuous strip and change from north to south, and which ones are located in separate areas and change from west to east?
Remember on which of the previously studied continents you have already encountered a vivid manifestation of such an arrangement of natural zones. What is causing this?
Conclusion 1... All natural zones are represented in Eurasia the globe, but only the zones of arctic deserts, tundra, forest-tundra and coniferous forests form continuous stripes that stretch from west to east across the entire continent, gradually replacing each other. Violation of latitudinal zoning in the distribution of natural zones is most clearly traced in the west and east of Eurasia.
2. Characteristics of natural areas
(Group performances. Sample.)
Arctic deserts
In the far north of Eurasia, there is a zone of arctic deserts. In the west, this zone covers individual islands in the Arctic Ocean, in the east - in addition to the islands, also part of the coast. Most of its surface is almost all year round covered with snow and ice. Only in some places in the summer does the snow melt, and then at a low-power soil cover sparse vegetation of lichens and mosses grows, sometimes polar poppy and saxifrage are found. Arctic foxes, lemmings are found here, largest inhabitant arctic deserts - polar bear. The polar bear is a large animal in the Arctic. A significant part of the year lives on ice floes, eats fish, hunts seals. Polar bears are on the verge of extinction, taken under protection. On the hard-to-reach rocks of numerous islands and coasts, polar birds nest, forming “bird colonies”.
Tundra and forest-tundra
To the south, along the coast of Eurasia and on the adjacent islands, a narrow strip of tundra stretches, which expands with an increase in the severity of the climate if it moves to the east. Excessive moisture in the summer in the tundra forms thousands of lakes and swamps. In summer, the tundra is brightly colored: purple saxifrage, golden arnica, red poppies. As in the North American tundra, lichens, mosses, marsh grasses, berry plants - cloudberries, blueberries, lingonberries grow here on peat bog soils. In the south of the zone, dwarf trees - birches and willows appear, which spread along the ground. The tundra is bordered in the south by the forest-tundra zone. Scandinavian, Kola Peninsula On the island of Iceland, it is characterized by thickets of twisted birches and alders; among the tundra vegetation to the east, coniferous trees - Siberian spruce and various types of larch appear.
The fauna of the tundra and forest-tundra is not rich, but peculiar. Reindeer, arctic foxes, wolves, lemmings, white-haired hares, birds - polar owls, white and tundra partridges are found here, swans, eiders, white-fronted geese, ducks, and seagulls fly in the summer.
Temperate forests
To the south of the forest-tundra tundra, there are temperate forests, which are characterized by a variety of forest vegetation.
The coniferous forest zone, or taiga, covers large areas from the Atlantic to the Pacific Ocean. European and Asian taiga have certain differences. In the west, pine and spruce prevail, beyond the Urals - fir, Siberian cedar, in Eastern Siberia - larch. Deciduous trees are mixed with conifers: birch, aspen, alder. Coniferous forests grow on podzolic soils with a low humus content. Plants of coniferous forests tolerate excess moisture and severe frosts well. The most a big tree taiga - Siberian cedar ( cedar pine). It reaches 35-40 m in height and 2 m in spread. Lives for about 500 years.
Permafrost is widespread in the Asian part. The taiga has a rich and varied animal world, many fur-bearing animals: sable, beaver, ermine, as well as foxes, squirrels, marten, hares, chipmunks, lynxes. Large animals include moose and bears. There are many different birds: wood grouses, hazel grouses, cones, nutcrackers, woodpeckers. Some of the birds are subject to fishing: hazel grouses, partridges, black grouse. The main wealth of taiga forests is valuable timber.
The most resistant tree in the taiga is larch. She is not afraid of the most severe frosts, it grows even in the area of the cold pole. Larch wood is extremely durable.
Nowadays, forests have been changed by man and require immediate measures for their restoration and rational use.
Mixed forests are located in Eurasia not in a continuous strip, but only in Europe and East Asia.
In the west, mixed forests begin in the south of the Scandinavian Peninsula and extend to the foothills South Urals... In these forests, in addition to conifers, oak, linden, ash, elm, hornbeam grow. The soils are predominantly soddy-podzolic. The eastern part of the mixed forest zone is located in the basin of the middle reaches of the Amur and along the Sea of Japan and the Yellow Seas - in the area of monsoon action. The vegetation here is dense and varied. Along with Siberian species of coniferous trees, Mongolian oak, Amur linden, Manchurian walnut, maple are widespread here. The soils are brown, forest. In addition to the animals characteristic of the taiga, the Ussuri tiger is found, Amur cat, raccoon dog, black Ussuri bear, wild boar, sika deer.
The broadleaf forests of Eurasia also do not form a continuous strip. In western Europe, they stretch from the southern shores of the Baltic and North Seas, gradually stretching out on the East European Plain. Here on the brown forest soils oak and beech forests grow with an admixture of hornbeam, and in the Atlantic region - noble chestnut. In deciduous forests are found Noble deer, roe deer, wild boar, forest cat. Large areas of forests in Europe have been cut down and replaced by cultivated vegetation. In the east of the mainland, deciduous forests have declined only in mountainous areas. Towards the south, due to a decrease in precipitation and an increase in evaporation in central parts continent, forests are replaced by forest-steppe and steppe.
Forest-steppe and steppe
The forest-steppe stretches in a narrow strip from the Central Danube lowland to the Yenisei River.
Separate areas of the forest-steppe are found among forests and mountains in eastern Asia. In this zone, on gray forest and chernozem soils, steppes alternate with individual groves and copses. In the European forest-steppe, oak prevails among tree species, and birch prevails in the Western Siberia. The fauna is represented by both forest and steppe species: marten, roe deer, fox, badger, jerboa, birds - eagle, golden eagle.
The steppes are treeless spaces where cereal vegetation reigns. The steppe zone stretches with confusion from the lower reaches of the Danube and the banks of the Black and Azov seas, skirting the Ural Mountains from the south, to Altai, continuing on the elevated plains East Asia... Fertile chernozem soils are formed under the grassy cover of the steppes.
In our time, the steppes and forest-steppe are the most plowed up and modified by man natural zones. Rodents have survived from the animal kingdom in the steppes - field mice, marmots, ground squirrels, steppe eagles, sometimes bustard, are found from birds. Among the predators in the steppe there are foxes and steppe ferrets.
Conclusion 2. Largest area the mainland is occupied by natural zones of the temperate zone.
V. ASSIGNMENT OF THE STUDIED MATERIAL
Reception "Microphone"
Discussion of group performances (reviewing and opposing)
Reception "Cartographic workshop"
Tasks... Designate on a contour map the natural zones of the arctic deserts, tundra and forest-tundra, taiga, mixed and deciduous forests, forest-steppes and steppes.
Reception "Blitzopros"
· In the location of which natural zones of Eurasia the latitudinal zonal is most clearly traced. What are the reasons for violating the latitudinal strike of natural zones?
· How did the flora and fauna of the arctic deserts, tundra and forest-tundra adapt to the harsh climatic conditions?
· What is the reason for the variety of natural zones of the temperate climatic zone?
· What is the difference between the European taiga and the Asian one?
· Within which natural zones is the territory of Ukraine located?
· What natural area do you live in? How did the natural conditions of this area affect economic activity population in your area?
Vi. LESSON OUTCOME, REFLEXION
The teacher reminds the students of their assumptions about the peculiarity natural landscapes Eurasia. Did your assumptions come true? What types of research were conducted in the lesson?
Vii. HOMEWORK
1. Work out the corresponding paragraph of the textbook.
2. Leading (for the following groups of students): prepare a description-presentation of natural zones of semi-deserts and deserts, subtropical forests, savannas, subequatorial and equatorial forests, vertical zoning in the Alps and the Himalayas.
Additional description: The image is synthesized in pseudo colors. The site of the Betpak-Dala sandy-saline desert (Northern Hungry Steppe) is presented. Located in Kazakhstan between the lower reaches of the Sarysu River, the Chu River and Lake Balkhash. Gray and brown shades are sand. Aquamarine and white tones are salt marshes. Yellow and yellow-green shades - rare shrubs and herbaceous vegetation in poor condition (dry). Green tones - shrubs, woody vegetation (in ravines and hills). Bright green tones - reeds and grass in lowlands (lakes) with a close location of groundwater.
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