Eurasia is the largest continent on our planet, for a long time remained the least explored. It is washed by the waters of four oceans, on its territory all climatic zones. The nature of Eurasia is so diverse that it is easy to find areas with completely opposite conditions. The contrasts of the continent are determined by its topography, extent and history of formation.
Features of the geographical location
The continent is washed by the Arctic, Atlantic, Pacific and Indian Oceans. Eurasia's closest neighbors are Africa and North America. The mainland is connected to the first through the Sinai Peninsula. North America and Eurasia are separated by the relatively small Bering Strait.
The continent is conventionally divided into two parts: Europe and Asia. The border between them runs along the eastern foot of the Ural Mountains, then along the riverbed along the northern coast of the Caspian Sea, the Kuma-Manych depression, along the line where the waters of the Black and Sea of Azov and, finally, along the straits connecting the Black and Mediterranean seas.
The coastline of the continent is quite indented. In the west, the Scandinavian Peninsula stands out, in the south - the Arabian and Hindustan. The east coast is also very shallow in places Pacific Ocean. Here you can find entire chains of islands: Kamchatka, Greater Sunda and so on. The north of the continent is less rugged. The areas of land that protrude into the ocean more than others are the Kola and Chukotka.
The nature of the Eurasian continent as a whole is determined by the influence of ocean waters only to a small extent. The reason for this is the considerable extent of the continent and the features of its relief. Vast areas of Eurasia remained poorly studied for a long time. A special contribution to the development of Asian territories was made by Pyotr Petrovich Semenov-Tyan-Shansky and Nikolai Mikhailovich Przhevalsky.
Relief
The natural wonders of Eurasia are, first of all, its contrast. It is largely due to the peculiarities of the continent's topography. Eurasia is higher than all other continents. There are mountain ranges here that are larger in size than similar formations in Africa, Australia and the Americas. The most famous peak of the mainland is Everest, or Chomolungma. This is the highest point on the planet - 8848 meters above sea level.
The plains of Eurasia occupy vast areas. There are much more of them than on other continents. The lowest point of the planet on land is also located here - this is a depression Dead Sea. The difference between it and Everest is approximately 9 kilometers.
Formation
The reason for such a variety of surface topography lies in the history of its formation. The continent is based on the Eurasian lithospheric plate, consisting of sections of different ages. The “oldest” areas are the South China, East European, Siberian and Sino-Korean platforms. They are connected by later rock formations. As the continent formed, fragments of ancient Gondwana were added to these platforms, which today underlie Hindustan and the Arabian Peninsula.
The southern edge of the Eurasian plate is a zone of increased seismic activity. Mountain building processes take place here. In the eastern part of the continent, the edge of the Pacific plate went under the Eurasian plate, resulting in the formation of deep depressions and extended island arcs. Earthquakes and related disasters are not uncommon in this area.
There are also a large number of volcanoes located in the so-called Ring of Fire of the Pacific Ocean. The highest one operating in Eurasia is (4750 m above sea level).
Glaciation, which in ancient times occupied the northern part of the continent, also made a significant contribution to the formation of the continent's topography.
Plains and mountains, old and young
The nature of Eurasia has undergone many changes. The vast West Siberian Plain, which occupies one of the largest areas in the world, was once the bottom of the sea. Today only reminders of the distant past big number sedimentary rocks found here.
The mainland's mountains were not always what they look like today. The most ancient of them are Altai, Ural, Tien Shan, Scandinavian. The process of mountain building here was completed long ago, and time has left its mark on them. The massifs are severely destroyed in places. In some areas, however, later uplifts also occurred.
“Young” mountain ranges form two belts in the southern and eastern parts of the continent. One of them, the Alpine-Himalayan, includes the Pamirs, the Caucasus, the Himalayas, the Alps, the Carpathians, and the Pyrenees. Some of the belt's ridges converge to form highlands. The largest of them is the Pamirs, and the highest is Tibet.
The second belt, the Pacific, extends from Kamchatka to the Greater Sunda Islands. Many of the mountain peaks located here are extinct or active volcanoes.
Riches of the Continent
The natural features of Eurasia include minerals that are unique in their diversity. On the mainland, tungsten and tin, which are necessary for industry but rarely found, are mined. Their deposit is located in the eastern part of the continent.
Gold, as well as diamonds, rubies and sapphires are also mined in Eurasia. The mainland is rich in iron ore deposits. Oil and gas are produced in large quantities here. In terms of reserves of these minerals, Eurasia is ahead of all other continents. The largest deposits are located in Western Siberia, on the Arabian Peninsula. Natural gas and oil have also been found at the bottom of the North Sea.
Eurasia is also famous for its coal deposits. Bauxite, table salt and potassium salt are also mined on the mainland.
Climate
The diversity of nature in Eurasia is largely due to the peculiarities of climatic conditions. The mainland is famous for its rather sharp changes, both from north to south and from east to west. The main features of the nature of Eurasia and Hindustan were formed under the influence of monsoons. Part of the year they blow from the ocean and bring huge amounts of precipitation. In winter, the monsoons come from the continent. In summer, a zone forms above the heated ground low blood pressure, and equatorial air masses come here from the ocean.
The natural features of Eurasia in the southern part of the continent are associated with high mountain ranges stretching from west to east. These are the Alps, the Caucasus, the Himalayas. They do not allow cold air from the north to pass through and at the same time do not interfere with the penetration of wet masses coming from Atlantic Ocean.
The wettest places on the continent are those where the ocean monsoons meet the mountain ranges. Thus, a large amount of precipitation falls on the southern slopes of the Western Caucasus. One of the wettest places on the planet is located in India, at the foot of the South-Eastern Himalayas. The city of Cherrapunji is located here.
Climate zones
The nature of Eurasia changes as you move both from north to south and from west to east. Climate zones play an important role in this. The northern and eastern parts of the mainland, including the Arctic islands, are arid and cold areas. Low temperatures prevail here; the air warms up somewhat only in the summer. In winter, the Arctic climate is characterized by severe frosts.
The next zone has less harsh conditions. The subarctic climate in Eurasia prevails over a small area stretching in a narrow strip from west to east. It also includes the island of Iceland.
The largest territory on the mainland is occupied by the northern temperate zone. It is characterized by a gradual change in climate types as you move from west to east. The areas of Eurasia bordering the Atlantic Ocean are characterized by warm and mild winters with frequent rain and fog (temperatures do not fall below 0º), cool cloudy summers (on average 10-18º) and high humidity (up to 1000 mm of precipitation falls here). Such features are typical for a marine temperate climate.
As you move away from the west coast, the influence of the Atlantic Ocean weakens. The temperate continental climate extends to the Ural Mountains. This territory is characterized warm summer And frosty winter. Beyond the Ural Mountains, the nature of the Eurasian continent is determined by the continental temperate climate. In Central and Central Asia it is very hot in summer and cold in winter. Temperatures may drop below 50º below zero. Due to the small amount of snow, the ground freezes to a fairly large depth.
Finally, in the east of the temperate zone the climate becomes monsoonal. Its main difference is the clear seasonal change in air masses.
It stretches from the Iberian Peninsula to the Pacific Ocean. It is also divided into zones. The subtropical Mediterranean climate is characterized by warm, rainy winters and hot, dry summers. As you move east, air humidity decreases. The central regions of the belt have a continental subtropical climate: hot summers, cold winters, low rainfall.
The east coast, washed by the waters of the Pacific Ocean, is characterized by high humidity. The air masses that come here in the summer pour down endless rains, causing rivers to overflow. In winter, the subtropical monsoon climate differs in temperatures up to 0º.
Diversity of nature in Eurasia: natural areas
The climatic zones of the continent provide unique diversity of flora and fauna. All natural areas found on the planet are represented here. Many of them are quite strongly modified by man. This is especially true for areas suitable for agriculture and areas comfortable for living. The wild nature of Eurasia, however, has been partially preserved, and today every possible effort is being made so that, even after a long time, people know what the area around them was originally like.
Natural wonders on the Eurasian continent are not uncommon. There are plants and animals here that are not found anywhere else. The diversity of the nature of Eurasia is created in some places by a smooth and sometimes quite abrupt change in climatic zones.
Harsh North
A narrow strip across the territory of Eurasia stretches a zone of arctic deserts, tundra and forest-tundra. Due to the harsh climate, there is little vegetation here. Vast areas of land remain “bare” all year round. Among the animals you can find here are polar bears, reindeer, and arctic foxes. The area is characterized by a large number of birds arriving in the warm season.
The tundra is particularly arid and has impressively deep permafrost. These features lead to the formation of swamps characteristic of the area.
Taiga
To the south of the tundra, swamps also occur in large numbers. The taiga located here is divided into European and Asian. The first is dominated by coniferous species such as pine and spruce. Birch, rowan and aspen trees are adjacent to them. As you move south, maples and oaks, as well as ash trees, become more common. The Asian taiga is the birthplace of cedar and fir. Larch, a coniferous tree that sheds its leaves for the winter, is also found in large numbers here.
The animals of the taiga are also very diverse. Brown bears, snowshoe hares, squirrels, moose, wolves, foxes and lynxes, as well as forest lemmings, martens, ferrets and weasels live here. Bird polyphony is a familiar background for these places. Here you can find woodpeckers, ptarmigan, black grouse, wood grouse, owls and hazel grouse.
Forest edge
The nature and animals of Eurasia change along with climatic conditions. The main part is concentrated on the vast territory of the East European Plain mixed forests mainland. As they move westward, they gradually disappear and reappear on the Pacific coast.
In mixed forests, coniferous, small-leaved and broad-leaved species grow together. There are much fewer swamps here, the soils are soddy-podzolic, and the grass cover is well defined. The broad-leaved forests of the Atlantic zones are characterized by beech and oak. As you go deeper to the east, the latter begins to predominate. Hornbeam, maple and linden trees are also found here. On the Pacific coast, due to the monsoon climate, the composition of forests is also very diverse.
The fauna is represented here by wild boars, roe deer, deer, as well as almost all the “residents” of the taiga. Brown bears are found in the Alps and Carpathians.
Changed zone
To the south lie forest-steppe and steppe. Both zones have been quite strongly altered by humans. Forest-steppe is alternating areas of forest and herbaceous vegetation. The steppe zone is mainly represented by cereals. Rodents, gophers, voles, and marmots are found here in large numbers. The natural vegetation of the area has been preserved today only on the territory of the reserves.
The eastern part of the Gobi Plateau is a zone of dry steppes. Low grasses grow here, and there are areas completely devoid of vegetation or saline.
Devoid of vegetation
Semi-desert and desert zones occupy a large part of the continent. They extend from the Caspian lowland across the plains of Central and Central Asia. The main features of the nature of Eurasia here are the almost complete absence of vegetation and poor fauna. Extremely low rainfall, dry air, clay and rocky soils do not even encourage the appearance of grass in this area. Quite sparse vegetation is found in sandy deserts. Wormwood, astragalus, saxaul, and solyanka “live” here.
The fauna of deserts is also scarce. However, here you can find quite rare representatives of the fauna, for example wild kulans and Przewalski's horse. Rodents and camels are common in this area.
Subtropics
Warm winters with high rainfall and hot, dry summers are good conditions for hard-leaved forests and shrubs that stretch along the coast Mediterranean Sea. Cork and cypress, pine, and wild olive trees are found here. The nature of Eurasia has undergone many changes due to human activity. Forests in the modern Mediterranean have been almost completely cut down. Their place was taken by low trees and shrubs.
The subtropics in southern China and the Japanese islands look somewhat different. Magnolias, palms, camellias, ficuses, camphor laurel and bamboo grow here.
In the interior of the continent there are subtropical and tropical deserts and semi-deserts. This zone is characterized by dry, hot weather and low rainfall. The flora is presented in the same way as in the deserts of the temperate zone. In addition, acacias are found here, and date palms grow in oases. The fauna is not numerous: Przewalski's horse, wild ass, jerboas, antelopes, jackals, hyenas, wild donkeys, onagers, gerbils.
Near the equator
The savannahs of Eurasia are a place where a large number of cereals grow, as well as teak and sal trees, acacias, and palm trees. Vast areas are covered by variable-humid subequatorial forests. They are located on the coasts of Hindustan and Indochina, in the lower reaches and Brahmaputra, as well as in the northern part of the Philippine Islands. Only some trees growing here shed their leaves during the dry season.
On Saturday equatorial forests The fauna is very diverse. A variety of ungulates, monkeys, lions and tigers, as well as wild elephants are found here.
Equatorial forests amaze with the diversity of palm trees. There are over three hundred species here, including coconut. There is also a lot of bamboo in this area.
Climatic zones of mountainous regions
Features of the nature of the Eurasian continent include a clearly noticeable change in the flora and fauna in the Alps and Himalayas. These mountain systems are the highest in Europe and Asia, respectively. The Alps reach a maximum of 4807 meters (Mont Blanc).
On the southern slopes there is the lower zone of the altitudinal zone. It extends up to 800 m and has features of a Mediterranean climate. In the western part of the Alps there are mainly mixed and beech forests. In the east, in the lower zone, the climate is drier. Pine and beech forests grow here, interspersed with steppe meadows. The second belt extends to 1800 m. There are oak and beech forests and coniferous trees. The next, subalpine, belt (up to 2300 m) is characterized by shrubs and meadow vegetation. Above that, only crustose lichens are found.
At the foot of the Eastern Himalayas are the Terai, wetlands. Palm trees, bamboo and sal grow here. The fauna of this area is quite diverse. Here you can find snakes, elephants, tigers, rhinoceroses, monkeys, leopards and so on. The territory from 1500 to 2000 m above sea level is occupied by evergreen subtropical forests. Higher up the number of deciduous and coniferous species. The belt of shrubs and meadow vegetation begins at 3500 m.
Due to the peculiarities of geography and the diversity of nature, Eurasia is a unique place on our planet. The contrasts of the continent contribute to the constant interest in it on the part of researchers and travelers. However, a description of the nature of Eurasia without mentioning traces of human activity seems somewhat ideal. As on any other continent, the territory here has undergone a lot of changes. A huge number of people living on the mainland need developed agriculture, constant mining. Therefore, the areas suitable for this are very different from the state in which they were at the dawn of mankind. Today Eurasia is vast fields, big cities and abandoned villages, huge industrial complexes. Preserving wildlife often fails. Nature reserves have been created to save rare species of animals and plants, but they do not fully cope with the task. However, the opinion about the need careful attitude to the outside world is increasingly finding support from government organizations. I would like to believe that thanks to this amazing nature Eurasia, photos of which are found on the pages of all thematic magazines, will be preserved in the future not only in photographs.
Eurasia is characterized by clearly defined geographical boundaries. This continent represents all existing zones, from equatorial forests to arctic deserts. Each of them has some characteristics, including unique flora and fauna.
As for mixed and deciduous forests, there are practically none left. In Europe, secondary plantings appeared in their place, and in Asia, arable lands were created. However, this zone is characterized by maple, oak, hornbeam, elm, and beech.
Steppes are nothing more than vast expanses of grassy vegetation. Unfortunately, they have been preserved in their original form only on the territory of nature reserves - only there you can study natural landscapes. The rest of the territory was allocated for agriculture. This zone is inhabited mainly by rodents.
Deserts and semi-deserts - these natural zones of Eurasia are located mainly in the central part of the continent (for example, the Gobi Desert). Conditions in these areas are far from optimal - low precipitation, cold winters and hot summers. Interestingly, there are places with so-called quicksand. As for the vegetation, here it is represented by solyanka, wormwood, sandy sedge and saxaul. This area is inhabited by rodents, some ungulates and representatives of reptiles.
The zone of hard-leaved forests and shrubs is located in the subtropical zone, or more precisely, in its western part. In the remaining forests you can see thickets of bamboo, as well as magnolia, camphor and laurel. But wild animals at one time were almost completely exterminated. Only in the highlands of Western Asia do hyenas, foxes and antelopes still live.
Savannas - these natural zones of Eurasia are represented mainly on the coasts of Indochina and Hindustan. The fauna here is very rich - tigers, elephants, buffalos, rhinoceroses, deer, antelopes, monkeys. These areas are mostly planted, but there are also real groves of Indian acacia. There are also valuable species, for example, sal and teak wood, from which expensive, rare types of wood are obtained.
Eurasia is the largest continent on Earth, consisting of two parts of the world - Europe and Asia. Together with the islands, Eurasia occupies an area of about 53.4 million km2, of which the islands account for about 2.75 million km2. Extreme continental points of Eurasia:
in the north – Cape Chelyuskin (770 43’ N, 104018’ E);
in the south – Cape Piai (1°16’N, 103030’E);
in the west – Cape Roca (38048’ N, 90 31’ W);
in the east - Cape Dezhnev (660 05'N, 169°40" W)
A number of islands in southeastern Eurasia are located in Southern Hemisphere. Eurasia is washed by oceans: in the west - the Atlantic, in the north - the Arctic, in the south - the Indian, in the east - the Pacific, and their marginal seas. In the southeast, the Australasian seas separate Eurasia from Australia, in the northeast, the Bering Strait from North America, in the southwest, the Strait of Gibraltar, the Mediterranean and Red Seas from Africa, with which Eurasia is connected by the Suez Canal. The continuity of the landmass, the modern tectonic consolidation of the continent, the unity of many climatic processes, the significant commonality of the development of the organic world and other manifestations of natural historical unity, as well as the need to take into account the significance territorial integrity to assess socio-historical phenomena, there was a need for a name that unites the entire continent. The concept of “Eurasia” introduced into geology and geography by E. Suess in 1883 turned out to be most convenient.
Eurasia is the arena of ancient civilizations. Thousands of years of agricultural culture have transformed the natural landscape of the low-lying plains of South and East Asia, the oases of Central, Central and Western Asia, and the southern coasts of Europe. The territory of most of Europe underwent radical transformations, and a significant part of Asia was developed. The modern cultural landscape dominates the territory of most of Europe, the plains of Great China, the Indo-Gangetic plains, the Indochina Peninsula, the islands of Java and the Japanese archipelago.
Eurasia is distinguished by the significant complexity of its geological history and mosaic geological structure. The skeleton of Eurasia is fused from fragments of several ancient continents: in the north-west - Laurentia, the eastern part, which, after the Cenozoic subsidence in the Atlantic Ocean, separated from North America and formed the European ledge of Eurasia; in the northeast - the Angarides, which in the late Paleozoic was articulated with Laurentia by the folded structure of the Urals, resulting in the formation of Laurasia, which existed until the middle of the Mesozoic; in the south - Gondwana, after the collapse of which the Arabian and Indian platforms were attached to Eurasia.
The structural plan of the modern relief of Eurasia was laid down in the Mesozoic, but the formation of the main features of the surface is due to the latest tectonic movements that swept Eurasia in the Neogene-Anthropocene, and these movements manifested themselves here more intensely than anywhere else on Earth. These were vertical movements of large scale - arch-block uplifts of mountains and highlands, lowering of depressions with partial restructuring of many structures. The uplifts covered not only the Alpine folded structures, but also rejuvenated and often revived the mountainous relief in older structures that experienced leveling in the Cenozoic. Intensity newest movements determined the predominance of mountains in Eurasia (the average height of the continent is 840 m) with the formation of the highest mountain systems (Himalayas, Karakoram, Hindu Kush, Tien Shan) with peaks exceeding 7-8 thousand m. The massive Western Asian plateaus, Pamirs, Tibet were raised to significant heights . These uplifts are associated with the revival of mountains in the vast belt from Gissar-Alai to Chukotka, the Kunlun, Scandinavian and many others. Rejuvenation during the latest uplifts was experienced by the middle mountains of the Urals, Central Europe, etc. and, to a lesser extent, by extensive plateaus and plateaus (Central Siberian Plateau , Dean, etc.). From the east, the continent is bordered by marginal uplifts (Koryak Highlands, Sikhote-Alin Mountains, etc.) and is accompanied by mountain-island arcs, among which there are East Asian and Malay arcs. Rift structures also play a major role in the relief of Eurasia - the Rhine graben, the basins of Baikal, the Dead Sea, etc. Young folded belts and structures of revived mountains are characterized by particularly high seismicity - in terms of intensity and frequency of destructive earthquakes, only Eurasia can be compared South America. Volcanism often participated in the creation of the relief of young uplifts (lava sheets and volcanic cones of Iceland and the Armenian Highlands, active volcanoes of Italy, Kamchatka, island arcs in the east and southeast of Asia, extinct volcanoes of the Caucasus, Carpathians, Elbrus, etc.).
Recent subsidence has led to the flooding of many of the outskirts of the continent and the isolation of the archipelagos adjacent to Eurasia (the Far East, the British Isles, the Mediterranean Sea basin, etc.). The seas have repeatedly attacked different parts of Eurasia in the past. Their deposits formed the sea plains, which were subsequently dissected by glacial, river and lake waters. The most extensive plains of Eurasia are the East European (Russian), Central European, West Siberian, Turanian, Indo-Gangetic. In many areas of Eurasia, sloping and basement plains are common. Ancient glaciation had a significant impact on the relief of the northern and mountainous regions of Eurasia. Eurasia contains the world's largest area of Pleistocene glacial and aquiglacial deposits. Modern glaciation is developed in many highlands of Asia (Himalayas, Karakoram, Tibet, Kunlun, Pamir, Tien Shan, etc.), in the Alps and Scandinavia, and is especially powerful on the Arctic islands and Iceland. In Eurasia, underground glaciation - permafrost and ice wedges - is more widespread than anywhere else in the world. In areas where limestone and gypsum occur, karst processes are developed. The arid regions of Asia are characterized by desert forms and types of relief.
- The concept of natural areas and the reasons for their formation
Physical-geographical zones are natural land zones, large divisions of the geographical (landscape) shell of the Earth, naturally and in a certain order replacing each other depending on climatic factors, mainly on the ratio of heat and moisture. In this regard, a change of zones and belts occurs from the equator to the poles and from the oceans to the interior of the continents. They are usually elongated in the sublatitudinal direction and do not have clearly defined boundaries. Each zone has typical features of its constituent natural components and processes (climatic, hydrological, geochemical, geomorphological, soil nature, vegetation and fauna), its own type of historically established relationships between them and the dominant type of their combinations - zonal natural territorial complexes. Many physical-geographical zones are traditionally named according to the most striking indicator - the type of vegetation that reflects the most important features most natural components and processes (forest zones, steppe zones, savannah zones, etc.). The name of these zones is often assigned to individual components: tundra vegetation, tundra-gley soils, semi-desert and desert vegetation, desert soils, etc. Within the zones, which usually occupy vast strips, narrower divisions are distinguished - physical-geographical subzones. For example, the savannah zone as a whole is characterized by a seasonal rhythm of development of all natural components, determined by the seasonal supply of atmospheric precipitation. Depending on the amount of the latter and the duration of the rainy period, subzones of wet tall grass, typical dry and desert savannas are distinguished within the zone; in the steppe zone - dry and typical steppes; in the temperate forest zone - subzones of taiga (often considered an independent zone), mixed and deciduous forests, etc.
Natural zones, if they are formed under more or less similar geological and geomorphological (azonal) conditions, are repeated in general terms on different continents with a similar geographical location (latitude, position in relation to the oceans, etc.). Therefore, zone types are distinguished, which are typological units of the territorial classification of the geographical envelope (for example, tropical western oceanic deserts). At the same time, the local features of a particular territory (relief, rock composition, paleogeographical development, etc.) give individual features to each zone, and therefore specific natural zones are considered as regional units (for example, the Atacama Desert, the Himalayas, a desert Namib, West Siberian Plain.). In the physical-geographical atlas of the world for 1964, the distinction of 13 geographical zones was adopted, based on the climatic classification of B. P. Alisov: an equatorial zone and two (for both hemispheres) subequatorial, tropical, subtropical, temperate, subpolar and polar (supporters of the thermal factor, as the main one in the formation of zoning, are limited to identifying only five or even three zones). Inside the belts, it is possible to identify sub-belts or stripes.
Each belt and each of its large longitudinal segments - sectors (oceanic, continental and transitional between them) are characterized by their own zonal systems - their own set, a certain sequence and extent of horizontal zones and subzones on the plains, their own set (spectrum) altitude zones in the mountains. Thus, the forest-tundra zone is inherent only in the subpolar (subarctic) zone, the taiga subzone is characteristic of the temperate zone, the “Mediterranean” subzone is characteristic of the western oceanic sector of the subtropical zone, the monsoon mixed forest subzone is of its eastern oceanic sector, and forest-steppe zones exist only in the transition sectors. The forest-tundra spectrum of altitudinal zones is characteristic only of the temperate zone, and the hyleinoparamos spectrum is characteristic only of the equatorial zone. Depending on the position in a particular sector or on a particular morphostructural basis, smaller taxonomic units can be distinguished within zones and subzones - typological: Western-oceanic dark-coniferous taiga, continental light-coniferous taiga, etc., or regional: Western- Siberian taiga, Central Yakut taiga, West Siberian forest-steppe, etc.
Since natural zones are determined mainly by the ratio of heat and moisture, this ratio can be expressed quantitatively (the physical and quantitative basis of zonality was first formulated in 1956 by A. A. Grigoriev and M. I. Budyko). For this purpose, various hydrothermal indicators (most often moisture indicators) are used. The use of these indicators helps, first of all, to develop theoretical issues of zoning, identify general patterns, and objectively clarify the characteristics of zones and their boundaries. For example, with values of the radiation index of Budyko dryness less than 1 (excessive moisture), humid zones of forests, forest-tundra and tundra dominate, with values greater than 1 (insufficient moisture) - dry zones of steppes, semi-deserts and deserts, with values close to 1 (optimal moisture) , - zones and subzones of forest-steppes, deciduous and light forests and wet savannas. The definition and further refinement of quantitative indicators are also of great practical importance, for example, for the application of various agricultural activities in various sectors, zones, subzones. At the same time, it is very important to take into account not just the similarity of the final indicators, but also what exact quantities they are made up of under given conditions. Thus, establishing the “periodic law of zoning,” A. A. Grigoriev noted the periodic repetition identical values radiation index of dryness in zones of different zones (for example, in the tundra, subtropical hemihylea and equatorial forest swamps). However, despite the generality of the index, both the annual radiation balance and the annual amount of precipitation in these zones are sharply different, just as all natural processes and complexes in general.
Along with zonal factors, the formation and structure of zonal systems is greatly influenced by a number of azonal factors (in addition to the primary distribution of land and oceans, which largely determines circulation, currents and moisture transfer). First of all, there is a polar asymmetry of the landscape shell of the Earth, expressed not only in the greater oceanicity of the Southern Hemisphere, but also in the presence, for example, of the subtropical hemihyla subzone peculiar only to it and, on the contrary, in the absence of many zones and subzones of the Northern Hemisphere (tundra, forest-tundra, taiga, deciduous forests, etc.). In addition, the configuration and size of the land area in certain latitudes play a significant role (for example, the widespread distribution of tropical deserts in North Africa and Arabia or Australia and their limited territory in the smaller tropical zones of North America or South Africa). The nature of large relief features also greatly influences. The high meridional ridges of the Cordillera and Andes enhance continentality and determine the presence of corresponding semi-desert and desert zones on the internal plateaus of the subtropical and tropical zones. The Himalayas contribute to the immediate proximity of the high-mountain deserts of Tibet and the moist forest zonal spectrum of the southern slopes, and the Patagonian Andes are even the root cause of the presence of semi-desert zones in the temperate zone in the east. But usually the influence of regional factors only strengthens or weakens general zonal patterns.
Of course, zonal systems underwent significant changes in the process of paleogeographical development. Belt and sector differences have already been established for the end of the Paleozoic. Later, changes occurred in the distribution of land and sea, macroforms of relief, and climatic conditions, and therefore, in the emerging zonal systems, some zones disappeared and were replaced by others, and the extent of the zones varied. Modern zones are of different ages; Due to the enormous role that Pleistocene glaciation played in their formation, the youngest zones are the high latitude zones. In addition, the increased temperature contrast between the poles and the equator in the Pleistocene increased the number of physiographic zones and significantly complicated their system. Human influence also had a great influence, in particular on the boundaries of zones.
The map in the appendix clearly shows the distribution of zones by zones and sectors and the differences in the manifestation of zonality in the high and middle latitudes of the Northern and Southern Hemispheres. In the high latitude belts (polar, subpolar and northern part of the northern temperate zone - the boreal subbelt, absent on land in the Southern Hemisphere) relatively small changes in the ratios of heat and moisture and excess moisture are observed almost everywhere. Natural differentiation is associated mainly with changes in thermal conditions, that is, with an increase in the radiation balance with a decrease in latitude. Consequently, the zones of polar deserts, tundra, forest-tundra and taiga extend sublatitudinally, and sectoral differences are weakly expressed (ice deserts in the Atlantic sector of the Arctic are mainly due to regional characteristics). At the same time, the polar asymmetry of the zonal spectra, caused by contrasts in the distribution of land and oceans in different hemispheres, is most pronounced. In the subboreal subbelts, with an even greater increase in heat supply, the role of moisture also increases. Its increase is determined by the predominance of westerly winds, and in the east by extratropical monsoons. Humidity indices vary significantly both by latitude and longitude, which is associated with the diversity of zones and subzones and differences in their extent. Ocean sectors are occupied wet forests, transitional - forests, forest-steppes and steppes, continental - mainly semi-deserts and deserts. The most striking manifestation of these zonal features is observed in subtropical zones, within which latitudinal differences in radiation conditions are still large, and moisture comes from both the west (only in winter) and the east (mainly in summer). In low latitude belts (tropical, subequatorial and equatorial), the asymmetry of the hemispheres is smoothed out, the radiation balance reaches its maximum, and its differences by latitude are weakly expressed. The leading role in changes in the ratio of heat and moisture goes to the latter. In tropical (trade wind) zones, moisture enters only from the east. This explains the presence of relatively humid zones (tropical forests, savannas and woodlands) extending submeridionally in the eastern sectors, semi-deserts and deserts filling the continental and western sectors. Subequatorial belts receive moisture mainly from the equatorial monsoons, that is, its amount quickly decreases from the equator to the tropics.
- Natural areas of the Eurasian continent
- Location of natural zones on the Eurasian continent and their characteristics
Geographic zoning is a pattern of differentiation of the geographical (landscape) shell of the Earth, manifested in a consistent and definite change in geographical zones and zones, caused, first of all, by changes in the amount of radiant energy from the Sun falling on the surface of the Earth, depending on geographic latitude. Such zoning is inherent in most components and processes of natural territorial complexes - climatic, hydrological, geochemical and geomorphological processes, soil and plant cover and fauna, and partly the formation of sedimentary rocks. Reducing the angle of incidence sun rays from the equator to the poles causes the release of latitudinal radiation belts - hot, two moderate and two cold. The formation of similar thermal and, even more so, climatic and geographical zones is already associated with the properties and circulation of the atmosphere, which is greatly influenced by the distribution of land and oceans (the reasons for the latter are azonal). The differentiation of natural zones on land itself depends on the ratio of heat and moisture, which varies not only by latitude, but also from the coasts inland (sector pattern), therefore we can talk about horizontal zoning, a particular manifestation of which is latitudinal zoning, well expressed on the territory of the Eurasian continent .
Each geographical zone and sector has its own set (spectrum) of zones and their sequence. The distribution of natural zones is also manifested in the natural change of altitudinal zones, or belts, in the mountains, which is also initially determined by the azonal factor - relief, however, certain spectra of altitudinal zones are characteristic of certain belts and sectors. Zoning in Eurasia is characterized for the most part as horizontal, with the following zones identified (their name comes from the predominant type of vegetation cover):
- Arctic desert zone;
— zone of tundra and forest-tundra;
— taiga zone;
— zone of mixed and deciduous forests;
- zone of forest-steppes and steppes;
— zone of semi-deserts and deserts;
- zone of hard-leaved evergreen forests and shrubs (the so-called
"Mediterranean" zone);
— zone of variable-humid (including monsoon) forests;
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On the territory of Eurasia there are all types of natural areas of the Earth. The sublatitudinal extent of the zones is disrupted only in the oceanic sectors and mountainous regions.
Most of the Arctic islands and a narrow strip of coastline lie in Arctic desert zone, there are also cover glaciers (Spitsbergen, Franz Josef Land, New Earth and Severnaya Zemlya).
Located further south tundra and forest-tundra, which from a narrow coastal strip in Europe gradually expand in the Asian part of the mainland. Moss-lichen covers, shrubs and shrubby forms of willow and birch on tundra-gley permafrost soils, numerous lakes and swamps, and animals adapted to the harsh northern conditions (lemmings, hares, arctic foxes, reindeer and many waterfowl) are common here.
South of 69°N.
in the west and 65° N. in the east within the temperate zone dominate coniferous forests(taiga). Up to the Urals, the main tree species are pine and spruce; in Western Siberia, fir and Siberian cedar (cedar pine) are added to them; in Eastern Siberia, larch already dominates - only it has been able to adapt to permafrost. Coniferous species are often mixed with small-leaved trees - birch, aspen, alder, especially in areas affected by forest fires and logging sites.
Under conditions of acidic pine litter and leaching regime, podzolic soils are formed, poor in humus, with a peculiar whitish horizon. The fauna of the taiga is rich and diverse - the number of species is dominated by rodents, there are many fur-bearing animals: sables, beavers, stoats, foxes, squirrels, martens, hares, which are of commercial importance; The most common large animals are moose, brown bears, and lynxes and wolverines.
Most birds feed on seeds, buds, and young shoots of plants (grouse grouse, hazel grouse, crossbills, nutcrackers, etc.); there are insectivores (finches, woodpeckers) and birds of prey (owls).
In Europe and East Asia, the taiga zone changes to the south zone of mixed coniferous-deciduous forests.
Thanks to leaf litter and grass cover, organic matter accumulates in the surface layer of soil in these forests and a humus (turf) horizon is formed. That is why such soils are called soddy-podzolic. In the mixed forests of Western Siberia, the place of broad-leaved species is taken by small-leaved species - aspen and birch.
In Europe, south of the taiga is located deciduous forest zone, which wedges out near the Ural Mountains.
In Western Europe, under conditions of sufficient heat and precipitation, beech forests on brown forest soils predominate; in Eastern Europe they are replaced by oak and linden on gray forest soils, since these species tolerate summer heat and dryness better.
The main tree species in this zone include hornbeam, elm, elm in the west, maple and ash in the east. The grass cover of these forests consists of plants with wide leaves - broad grasses (wort grass, capitula, hoofweed, lily of the valley, lungwort, ferns).
Foliage and grass, rotting, form a dark and rather powerful humus horizon. Indigenous broad-leaved forests in most areas have been replaced by birch and aspen.
In the Asian part of the mainland, broad-leaved forests are preserved only in the east, in the mountainous regions. They are very diverse in composition with a large number of conifers and relict species, vines, ferns and a dense shrub layer.
Mixed and deciduous forests are home to many animals characteristic of both the taiga (hares, foxes, squirrels, etc.) and more southern latitudes: roe deer, wild boars, red deer; A small population of tigers remains in the Amur basin.
In the continental part of the continent south of the forest zone they are common forest-steppe and steppe.
In the forest-steppe, herbaceous vegetation is combined with areas of broad-leaved (up to the Urals) or small-leaved (in Siberia) forests.
Steppes are treeless spaces where grasses with a dense and dense root system thrive. Under them, the most fertile chernozem soils in the world are formed, the thick humus horizon of which is formed due to the conservation of organic matter during the dry summer period. This is the most human-transformed natural zone in the interior of the continent.
Due to the exceptional fertility of chernozems, steppes and forest-steppes are almost completely plowed. Their flora and fauna (herds of ungulates) have been preserved only in the territories of several reserves.
Numerous rodents have adapted well to the new living conditions on agricultural lands: ground squirrels, marmots and field mice. Inland regions with continental and sharply continental climates are dominated by dry steppes with sparse vegetation and chestnut soils. In the central regions of Eurasia, semi-deserts and deserts are located in the internal basins.
They are characterized by cold winters with frosts, so there are no succulents here, but wormwood, solyanka, and saxaul grow. In general, the vegetation does not form a continuous cover, as do the brown and gray-brown soils that develop under them, which are saline.
The ungulates of the Asian semi-deserts and deserts (wild donkeys, wild Przewalski's horses, camels) have been almost completely exterminated, and rodents, which mostly hibernate in winter, and reptiles dominate among the animals.
The south of the oceanic sectors of the continent is located in subtropical and tropical forest zones.
In the west, in the Mediterranean, the indigenous vegetation is represented by hard-leaved evergreen forests and shrubs, the plants of which have adapted to hot and dry conditions. Beneath these forests, fertile brown soils formed. Typical woody plants are evergreen oaks, wild olive, noble laurel, southern pine - pine, cypress. Few wild animals remain. Rodents can be found, including wild rabbit, goats, mountain sheep and a peculiar predator - the genet.
As elsewhere in arid conditions, there are a lot of reptiles: snakes, lizards, chameleons. Among the birds there are birds of prey - vultures, eagles and rare species such as the blue magpie and the Spanish sparrow.
In the east of Eurasia, the subtropical climate has a different character: precipitation falls mainly in the hot summer.
Once upon a time in East Asia, forests occupied vast areas; now they are preserved only near temples and in inaccessible gorges. The forests are diverse in species, very dense, with a large number of vines. Among the trees there are both evergreen species: magnolias, camellias, camphor laurel, tung tree, and deciduous ones: oak, beech, hornbeam.
Southern coniferous species play a major role in these forests: pines and cypresses. Under these forests, fairly fertile red and yellow soils have formed, which are almost completely plowed. Various subtropical crops are grown on them. Deforestation radically affected the composition of the animal world. Wild animals are preserved only in the mountains.
These are the Himalayan black bear, the bamboo bear - panda, leopards, monkeys - macaques and gibbons. Among the feathered population there are many large and colorful species: parrots, pheasants, ducks.
The subequatorial belt is characterized by savannas and variable-humid forests. Many plants here shed their leaves during the dry and hot winter. Such forests are well developed in the monsoon region of Hindustan, Burma, and the Malay Peninsula. They are relatively simple in structure, the upper tree layer is often formed by one species, but these forests amaze with the variety of vines and ferns.
In the extreme south of South and South-East Asia common equatorial rainforests.
They are distinguished by a large number of species of palm trees (up to 300 species), bamboo, many of them play a large role in the life of the population: they provide food, building material, and raw materials for some types of industry.
In Eurasia, large areas are occupied areas with altitudinal zones. The structure of altitudinal zones is extremely diverse and depends on the geographical location of the mountains, slope exposure, and height. Conditions are unique on the high plains of the Pamirs, Central Asia, and the Western Asian highlands.
A textbook example of altitudinal zones are the world's greatest mountains, the Himalayas - almost all altitudinal zones are represented here.
|
Natural area |
Climate type |
Climate Features |
Vegetation |
The soil |
Animal world |
||
|
TJan. |
TJuly |
Total precipitation |
|||||
|
Subarctic |
Islands of small birches, willows, rowan trees |
Mountain-arctic, mountain-tundra |
Rodents, wolves, foxes, polar owls |
||||
|
Forest-tundra |
Moderately marine |
birch and alder |
Illuvial-humus podzols. |
Elk, partridge, arctic fox |
|||
|
Coniferous forest |
Temperate temperate continental |
Norway spruce, Scots pine |
Podzolic |
Leming, bear, wolf, lynx, capercaillie |
|||
|
Mixed forest |
Moderate Temperate continental |
Pine, oak, beech, birch |
Sod-podzolic |
Wild boar, beaver, mink, marten |
|||
|
broadleaf forest |
Temperate marine |
Oak, beech, heather |
Brown forest |
Roe deer, bison, muskrat |
|||
|
Coniferous forests |
Moderate monsoon |
Fir, esl, Far Eastern yew, small-leaved birch, alder, aspen, willow |
Brown forest broadleaf forest |
Antelope, leopard, Amur tiger, mandarin duck, white stork |
|||
|
Evergreen subtropical forests |
Subtropical |
Masson pine, sad cypress, Japanese cryptomeria, lianas |
Red soils and yellow soils |
Asian mouflon, marking goat, wolves, tigers, marmots, ground squirrels |
|||
|
Tropical rainforests |
Subequatorial |
Palm trees, lychee, ficus |
Red-yellow ferrallite |
Monkeys, rodents, sloths, peacocks |
|||
|
Moderate |
Cereals: feather grass, fescue, tonkonogo, bluegrass, sheep |
Chernozems |
gophers, marmots, steppe eagle, bustard, wolf |
||||
|
Temperate, subtropical, tropical |
tamarix, saltpeter, solyanka, juzgun |
Desert sandy and rocky |
Rodents, lizards, snakes |
Lecture added 03/07/2014 at 14:48:58
Natural areas of Russia.
* Geographical position.
* Vegetable world.
* Animal world.
* Rare and endangered animals.
GEOGRAPHICAL POSITION:
* The taiga zone is the largest natural zone in Russia.
It stretches in a wide continuous strip from the western borders almost to the Pacific coast. The zone reaches its greatest width in Central Siberia (more than 2000 km). Here the flat taiga meets the mountain taiga of the Sayan and Cis-Baikal regions. The Russian taiga could cover almost all of Europe - an entire part of the world.
CLIMATE:
The taiga is characterized by moderately warm summers and cold winters with snow cover, especially harsh in Siberia.
In Central Yakutia, even the average January temperature drops below - 40. The average July temperature varies from + 13 in the north to +19 in the south. The sum of temperatures during the warm period also increases in the same direction.
Taiga is characterized by sufficient and excessive moisture. There are many swamps, including upland swamps, and lakes. Surface runoff in the taiga is higher than in other natural zones.
The river network is very dense. Snow melt water plays an important role in feeding rivers. Due to this, spring floods are observed.
THE SOIL.
* Taiga is coniferous forests of uniform composition. Under them, to the west of the Yenisei, podzolic and sod-podzolic soils are formed, and to the east, permafrost-taiga soils.
VEGETABLE WORLD.
* Taiga forests are usually formed by one layer of trees, under which there is a moss carpet with lingonberry and blueberry bushes and rare herbs.
Sometimes the second tree layer forms the young generation of the forest. Young fir trees and fir trees in the forest feel like their mother, and the pines feel like their stepmother. In order not to die, they must fight all their lives for a place in the sun, and not only with their sisters, but also with their parents. After all, pine is a light-loving species. In lighter forests, in some places, shrubs - elderberry, brittle buckthorn, honeysuckle, rose hips, wild rosemary, juniper - can form their own layer.
ANIMAL
WORLD.
The animals inhabiting it are well adapted to life in the taiga.
Common in the taiga are brown bear, elk, squirrel, chipmunk, mountain hare, typical taiga birds: wood grouse, hazel grouse, various woodpeckers, nutcracker, crossbill. Predators are also typical for the taiga: wolf, lynx, wolverine, sable, marten, ermine, fox.
Rare and endangered
animals.
Central forest biosphere state reserve formed in 1931 to preserve the southern border of the taiga, located in the Tver region, 50 kilometers north of the city of Nelidovo.
Conclusion.
* The dominance of evergreen coniferous trees in the taiga zone is the plant’s response to the duration of the frosty winter. The needles reduce evaporation, the diversity of animals is associated with varied and fairly plentiful food, and plenty of shelters.
Materials used.
We used the booklet: “Central Forest Reserve,” a geography textbook. Electronic encyclopedia of Cyril and Methodius.
Download abstract
Steppes are common on all continents except Antarctica; in Eurasia, the largest areas of steppes are located in Russian Federation, Kazakhstan, Ukraine and Mongolia. In the mountains it forms an altitudinal belt (mountain steppe); on the plains - a natural zone located between the forest-steppe zone in the north and the semi-desert zone in the south.
Atmospheric precipitation is from 250 to 450 mm per year.
The climate of steppe regions typically ranges from temperate continental to continental and is characterized by very hot summers and cold winters.
A significant part of the steppe territories is plowed.
A characteristic feature of the steppe is the treelessness of vast plains covered with rich grassy vegetation. Herbs that form a closed or almost closed carpet: feather grass, fescue, tonkonogo, bluegrass, sheep grass, etc.
Both in terms of species composition and some ecological features, the animal world of the steppe has much in common with the animal world of the desert.
Of the ungulates, typical species are distinguished by acute vision and the ability to run quickly and for a long time (for example, antelopes); of rodents - those that build complex burrows (gophers, marmots, mole rats) and jumping species (jerboas, kangaroo rats). Most birds fly away for the winter. Common: steppe eagle, bustard, steppe harrier, steppe kestrel, larks. Reptiles and insects are numerous.
Forest-tundra and tundra.
Forest-tundra- a subarctic type of landscape, in which, in the interfluves, oppressed light forests alternate with shrubby or typical tundra.
Average air temperatures in July are 10-12°C, and in January, depending on the increasing continentality of the climate, from −10° to −40°C.
With the exception of rare taliks, the soils are everywhere permafrost.
Soils are peaty-gley, peat-bog
Shrub tundras and open forests change due to longitudinal zonation. In the eastern part of the North American forest-tundra, black and white spruce grow along with dwarf birches and polar willows, and in the west, balsam fir
The fauna of the forest-tundra is also dominated by lemmings of various species in different longitudinal zones, reindeer, arctic foxes, white and tundra partridges, polar owls and a wide variety of migratory, waterfowl and small birds that settle in bushes.
Forest-tundra is a valuable reindeer pasture and hunting grounds.
Tundra- a type of natural zones lying beyond the northern limits of forest vegetation, spaces with permafrost soil that is not flooded by sea or river waters.
The tundra is located north of the taiga zone. The nature of the surface of the tundra is swampy, peaty, rocky. The southern border of the tundra is taken to be the beginning of the Arctic.
The tundra has a very harsh climate (the climate is subarctic), only those plants and animals that can withstand the cold live here. The winter is long (5-6 months) and cold (up to −50 ° C).
Summer is also relatively cold, the average temperature in June is about 12°C, and with the arrival of summer all the vegetation comes to life. The summer and autumn tundra is rich in mushrooms and berries.
Tundra vegetation consists primarily of lichens and mosses; The angiosperms found are low grasses (especially from the Poaceae family), shrubs and dwarf shrubs.
Wild deer, foxes, bighorn sheep, wolves, lemmings and brown hares are typical inhabitants of the Russian tundra. But there are not so many birds: Lapland plantain, white-winged plover, red-breasted pipit, plover, snow bunting, snowy owl and ptarmigan.
There are no reptiles in the tundra, but a very large number of blood-sucking insects.
Rivers and lakes are rich in fish (nelma, whitefish, omul, vendace, etc.).
Antarctic ice desert zone.
The Antarctic belt is the southern natural geographical zone of the Earth, including Antarctica with the adjacent islands and the ocean waters washing it.
Usually the boundary of the Antarctic belt is drawn along the 5 degree isotherm from the warmest month (January or February).
The Antarctic belt is characterized by:
- negative or low positive values radiation balance;
— Antarctic climate with low air temperatures;
- long polar night;
— the predominance of ice deserts on land;
— significant ocean ice cover.
Zoning and azonality.
The most important geographical pattern is zoning– a natural change in components or complexes from the equator to the poles due to a change in the angle of incidence of the sun's rays.
The main reasons for zonation are the shape of the Earth and the position of the Earth relative to the Sun, and the prerequisite is the incidence of sunlight on the Earth's surface at an angle that gradually decreases on both sides of the equator.
The founder of the doctrine of zonation was the Russian soil scientist and geographer V.V.
Dokuchaev, who believed that zonation is a universal law of nature. Geographers share the concepts of component and complex zoning. Scientists distinguish horizontal, latitudinal and meridional zoning.
Due to the zonal distribution of solar radiant energy on Earth, the following are zonal: air, water and soil temperatures; evaporation and cloudiness; atmospheric precipitation, baric relief and wind systems, VM properties, climates; the nature of the hydrographic network and hydrological processes; features of geochemical processes and soil formation; types of vegetation and life forms of plants and animals; sculptural relief forms, to a certain extent types of sedimentary rocks, and finally, geographical landscapes, united in this regard into a system of natural zones.
The zones do not form continuous stripes everywhere.
The boundaries of many zones deviate from parallels, and great contrasts in nature are observed within the same zones. Therefore, along with zonality, another geographical pattern is distinguished - azonality. Azonality– changes in components and complexes associated with the manifestation of endogenous processes.
The reason for azonality is heterogeneity earth's surface, the presence of continents and oceans, mountains and plains on the continents, the uniqueness of local factors: rock composition, relief, moisture conditions, etc. Endogenous relief is azonal, i.e. placement of volcanoes and tectonic mountains, structure of continents and oceans.
There are two main forms of manifestation of azonality - sectorality geographical zones and altitudinal zone.
Within geographic zones, three sectors are distinguished: continental and two oceanic. The sectorality is expressed most clearly in the temperate and subtropical geographical zones, and weakest in the equatorial and subarctic.
Altitudinal zonation is a natural change in zones from the foot to the top of a mountain.
Altitudinal zones are not copies, but analogues of latitudinal zones; their identification is based on a decrease in temperature with height, and not on a change in the angle of incidence of sunlight.
However, altitudinal zonality has much in common with horizontal zonality: the change of zones when ascending mountains occurs in the same sequence as on the plains when moving from the equator to the poles.
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All natural zones of the Northern Hemisphere are represented in Eurasia. In the western part of the continent, the dominant influence of the Atlantic Ocean led to a change in natural areas from northwest to southeast. In the eastern part of Eurasia, natural zones should be plotted meridionally, which is a consequence of the massive mass transfer of monsoons in the Pripihochanovsk region. Natural areas of the continent's interior vary in width due to changes in temperature and humidity from north to south.
The Arctic desert with very harsh natural and climatic conditions occupies the Arctic islands.
There is no continuous floor covering, and poor vegetation is a heat-resistant species that survives in constant cold conditions. Here are the common animals, polar bears, wet ones, seals, reindeer.
Due to the moderating influence of the North Atlantic flow, tundra and forest-tundra differ in their western and eastern regions.
Near the European coast of the continent, the climate is moderately cold, and the tundra extends to the north as anywhere on the planet. As you move eastward, natural and climatic conditions become more severe, and tundra and forest tundra occupy large areas. In the highlands of Siberia, tundra vegetation extends far to the south.
Among the plants, mosses and lichens predominate, which grow on the tundra and see the ground. Due to long-term frost, the humidity does not deepen, so there are a lot of swamps. Main animals: reindeer, arctic fox, some bird species
There is land to the south of the forested tundra. In warmer and more humid climates, huge areas of coniferous trees were created on podzolic soils from spruce, pine and larch (the only conifers, the needles settle in winter.
The latter predominate in the Asian Taiga, in a coldly harsh continental climate. In places where the taiga is very rich, there are many peat bogs and swamps.
The animal kingdom here is extremely diverse (brown bear, moose, black grouse, wolf, wood grouse).
Areas of mixed and deciduous forests are most common in western Eurasia. Here, under conditions of significant moisture, spruce-podzolic soil grows spruce-oak and pine oak forests of Western Siberia - coniferous and unpaved forests.
In addition to the east, mixed forests disappear and reappear only on the Pacific coast. Broad forests consist mainly of oak and beech, as well as hornbeam, maple, and lime
For the forest-steppe and steppe regions, there are certain differences in the ozone distance caused by significant climate change with progress from west to east of the continent.
In conditions of a warm climate and inadequate moisture, fertile black soils, as well as gray forest soil, were created south of the Russian Plain. The vegetation here contains small areas of forest (oak, birch, linden, maple). In the eastern part of the continent, if there is a temperature range and a dry climate increase, soil is often a physiological solution.
Here the flora is poorer and is mainly represented by grass and shrubs. The most typical representatives of the animal world are steppe and forest-steppe wolves, foxes, civet squirrels, voles, shrimp and steppe birds. Forested steppes and steppes are almost completely nourished, and natural vegetation is maintained only in protected areas and places that are not suitable for plowing
In large areas of the central and southwestern parts of the continent they occupy half of the desert and desert.
The desert zone extends into three geographical zones. The common denominator for all deserts is low rainfall, poor soil, and vegetation well adapted to difficult conditions.
The deserts of the Arabian Peninsula are characterized by high temperatures throughout the year, insignificant (up to 100 mm per year) precipitation and mostly flat surfaces. Deserts of subtropical plants (Iranian plateau, Central Asia, part of the Gobi Desert) are characterized by large temperature differences, richer vegetation, and a significant number of species. Covered with sand or rocks, the desert of the temperate Karakum zone, Taklamakan, part of the Gobi is characterized by very hot summers and severe frosts in winter
All natural areas are represented in Eurasia. In the north of the continent the zones stretch solid stripe, and to the south the taiga changes not only from north to south, but also from west to east, which is explained by differences in the amount of precipitation, which decreases from the outskirts of the continent to the interior regions.
The nature of the arctic desert, tundra and forest-tundra zones in Eurasia has much in common with similar zones in North America. However, in Eurasia these zones do not extend as far south as in North America. The natural zones of the temperate zone are quite diverse. The coniferous forest zone (taiga) stretches from the Atlantic to the Pacific Ocean. Climatic conditions in the zone change with movements from west to east, so the species composition of trees is different. In the west, pine and spruce predominate on podzolic soils; in Western Siberia, fir and Siberian cedar (cedar pine) grow in heavily swampy conditions; in eastern Siberia, larch is common on permafrost-taiga soils; and on the Pacific coast, there is dark coniferous taiga of Daurian larch, fir, Korean cedar. In the taiga there are many valuable fur-bearing animals (sable, ermine, marten), and large animals include moose, brown bears, lynxes, and many birds. The zone of mixed and deciduous forests is located only in the west and east of the temperate zone.
Mixed forests grow on soddy-podzolic, as well as brown and gray forest soils. For Europeans, broad-leaved forests are most characterized by oak and beech, maple and linden, hornbeam and elm. In the east of the zone, under monsoon climate conditions, Manchurian walnut, Amur velvet, oak, linden grow; there are many evergreen shrubs in the undergrowth, and there are thickets of bamboo. Very few natural forests remain. In Europe they gave way to secondary forests and artificial plantings, dominated by coniferous trees, and in Asia to arable lands. Many animals have been exterminated or become rare and are protected. Forest-steppes and steppes are located in the central parts of the continent, where precipitation decreases and evaporation increases.
Steppes are treeless spaces with herbaceous vegetation, under which fertile chernozem soils are formed; rodents predominate among animals. Steppes and forest-steppes are almost completely plowed, and only in nature reserves their natural landscapes are presented. In the Gobi, areas of dry steppes used for pastures have been preserved. Semi-deserts and temperate deserts lie in the central parts of the continent, where there is very little rainfall, hot summers and cold winters. The vegetation (wormwood, solyanka, saxaul, sandy sedge) is sparse, and there are desert areas with shifting sand. Soils contain a lot of mineral salts and little organic matter. Among the animals, reptiles, rodents and ungulates predominate.
In the western part of the subtropical zone there is a zone of hard-leaved forests and shrubs. Thanks to the mild and wet winter, plants grow here all year round, but the lack of moisture during the period of the most intense solar radiation has led to the appearance of adaptations in plants that reduce evaporation. In the past, forests of evergreen holm oak, laurel, myrtle, wild olives, and strawberry trees grew here. This vegetation has been destroyed almost everywhere, since farming has long been practiced here. The zone is characterized by brown and red soils, which are fertile and suitable for cultivating subtropical crops. In the east of the belt there is a zone of subtropical monsoon forests. The forests consist of laurel-leaved trees, camphor trees, magnolias, and bamboo thickets growing on yellow earth and red earth soils. There are almost no wild animals left. In the subtropical deserts on the highlands of Western Asia there are especially many ephemerals, which during the period of short spring rains manage to go through the entire development cycle. Among the animals that live here are antelopes, hyenas, fennec foxes and others. The nature of the tropical desert zone is in many ways reminiscent of the nature of the deserts of North Africa.
IN subequatorial belt Savannahs form on the plains and in intermountain basins, and variable-humid forests form on the coasts of Hindustan, Indochina and on the slopes of mountains facing the ocean. In savannas, among the grasses grow acacia, palm, Indian banana (ficus genus), one tree can imitate a whole grove). In the forests, along with deciduous trees, there are evergreen species. Plants that produce valuable wood (teak and sal trees) are common; palm trees and bamboo grow. The fauna is also rich: monkeys, elephants, tigers, buffaloes, rhinoceroses, antelopes, deer, etc. The equatorial forest zone is located mainly on islands and has not yet been as strongly altered by anthropogenic activities as other zones. Along with the common features characteristic of these forests located on other continents, there are many trees with valuable wood (iron, ebony, mahogany), plants that produce spices: cloves, pepper, cinnamon. One of the species lives in the forests great apes– orangutan, numerous hibons, loris prosimians, rhinoceros, wild ox. Areas of altitudinal zonation occupy a significant part of Eurasia. The Himalayas are a classic example of altitudinal zones; all altitudinal zones are represented here. In the mountains of Eurasia lies the upper limit of the distribution of vegetation on Earth - 6218 meters.
Since Eurasia lies in all climatic zones of the northern hemisphere, all natural zones of the globe are represented here.
Arctic deserts, tundra and forest-tundra
Zones of arctic deserts, tundra and forest-tundra stretch in a narrow continuous strip across the entire continent. The climate of the Arctic deserts is very strict. The vegetation is very poor. Large areas have no vegetation cover.
Here we meet the arctic fox, polar bear, reindeer. In summer, many waterfowl arrive; they settle on high rocky shores, forming bird colonies.
In the tundra there is little precipitation, temperatures are low, and permafrost is characteristic, which contributes to the formation of swamps.
Taiga
There are many peat and sedge bogs here. The European taiga is dominated by pine and spruce. They are mixed with small-leaved species - birch, aspen, rowan. South of 60°N. w. broad-leaved species appear in the forests - maple, ash, oak. In the Asian taiga, fir, Siberian pine or cedar grow, as well as larch - the only coniferous tree that sheds its needles for the winter.
The fauna of coniferous forests is very rich. It is home to elk, squirrel, mountain hare and forest lemming. The most common predators are wolf, fox, lynx, pine marten, ferret, weasel and brown bear. Otters live in ponds. Among the birds, the most numerous are crossbills, woodpeckers, ptarmigan, wood grouse, black grouse, hazel grouse and owls.
Mixed forests
The main part of mixed forests in Europe is located on the East European Plain and gradually disappears in a western direction. In these forests, broad-leaved species grow alongside coniferous and small-leaved species. There is already abundant grass cover on soddy-podzolic soils, and swamps are less common. In Asia there is also a zone of mixed forests, but it appears only in the Pacific sector of the temperate zone, where forests grow in a monsoon climate and their composition is more diverse.
Western, Atlantic broad-leaved forests are characterized by beech and oak. As we move east and the amount of precipitation decreases, beech forests are replaced by lighter oak forests.
Hornbeam, linden, and maple grow in broad-leaved forests. In addition to animals living in the taiga, there are wild boar, roe deer, and deer. The brown bear is found in the Carpathians and Alps.
Forest-steppe and steppe
In the forest-steppe, islands of forests on gray forest soils alternate with steppe areas. The steppes are dominated by herbaceous vegetation. Various grasses are most common in the grass cover.
Among the animals, rodents predominate - gophers, marmots, and field mice. Natural vegetation has been preserved only in nature reserves.
In the eastern part of the Gobi Plateau there are dry steppes: the grass is low or the soil surface is completely devoid of grass cover, and there are saline areas.
Semi-deserts and temperate deserts
These zones extend from the Caspian lowland across the plains of Central and Central Asia. Brown semi-desert soils and brown and gray-brown desert soils are developed here.
In deserts, conditions are unfavorable for plant development: little rainfall and dry air. In clayey and rocky deserts there is no soil cover of vegetation. In the sandy deserts of the temperate zone, saxaul, wormwood, solyanka, and astragalus grow.
The fauna of these zones is also poor. In semi-deserts and deserts the Przewalski's horse, wild kulan donkeys, camels, and various and numerous rodents are still preserved.
Subtropical forests and shrubs
A zone of hard-leaved evergreen forests and shrubs stretches along the Mediterranean coast. The climatic conditions of the zone are characterized by dry and hot summers, rainy and warm winters.
Holm and cork oaks, wild olive, Mediterranean pine, and cypress grow on chestnut soils. The forests on the shores of the Mediterranean Sea are now almost completely cut down. Now there are thickets of evergreen bushes and low trees growing here.
In the south of China and the Japanese islands there is a zone of variable-humid (monsoon) forests. Summers here are humid, winters are relatively dry and cool. In the forests on red soils and yellow soils, magnolias, palm trees, ficuses, camellias, camphor laurel grow, and bamboo is found.
Subtropical and tropical semi-deserts and deserts
Inland deserts feature hot and dry climates throughout Eurasia. The average July temperature can reach +30 °C. It rains extremely rarely.
The plants in these zones are the same as those in temperate deserts. Acacias grow along dry riverbeds, and date palms are grown in oases.
The fauna of deserts is relatively poor. In Arabia there are wild Przewalski's horses, wild ass, fleet-footed antelopes, and wild donkeys and onagers. There are also predators - striped hyena, jackal. Lots of rodents - jerboas, gerbils.
Savannas and subequatorial forests
In the savannas of Eurasia, palm trees, acacias, teak and sal trees grow among tall grasses. There are areas of sparse forests. Subequatorial humid variable-humid forests cover the western coast of Hindustan, the region of the lower reaches of the Ganges and Brahmaputra, the coast of the Indochina Peninsula and the northern part of the Philippine Islands. The vegetation of the zone resembles southern equatorial rainforests, but some trees shed their leaves during the dry season.
The fauna of savannas and subequatorial forests is diverse. Many ungulates, especially antelopes, many monkeys. Tigers and leopards hunt along the rivers of Hindustan. Wild elephants still live in Hindustan and on the island of Sri Lanka.
Equatorial rainforests
In Eurasia they occupy quite large areas and are diverse. There are more than 300 species of palm trees alone. It grows on the coast of the Philippine Islands and the Malay Archipelago. coconut palm. Numerous species of bamboos grow in equatorial forests.
Altitudinal zone
Brighter altitudinal zonations were found in the Alps and Himalayas - the highest mountain systems in Europe and Asia. The highest mountains of Europe are the Alps. Their highest point, Mont Blanc, reaches an altitude of 4807 m. In addition, this mountain system is an important climate for Europe. Glaciers and eternal snow decrease in the Alps to 2500-3200 m.
The highest mountain system in Asia and the entire globe is the Himalayas. Their highest point is the city of Chomolungma. The Himalayas are the natural boundary between the mountainous deserts of Central Asia and the tropical landscapes of South Asia.
At the foot of the Eastern Himalayas are the Terai. Tall bamboo, various palm trees, and sal tree grow in them. Elephants, rhinoceroses, buffaloes live here, among the predators are tigers, spotted and black leopards, many monkeys, and snakes. Above 1500 m and up to 2000 m there is a belt of evergreen subtropical forests. At an altitude of 2000 m, these forests give way to forests of deciduous species with an admixture of conifers. Above 3500 m the belt of bushes and alpine meadows begins.
On the southern slopes of the Alps, the landscapes of the lower altitudinal zone up to an altitude of 800 m have Mediterranean features. In the northern regions of the Western Alps, beech and mixed forests predominate in the lower belt; in the drier eastern Alps, oak and pine forests alternate with steppe meadows. Up to an altitude of 1800 m, a second zone with oak and beech forests with the participation of coniferous trees is common.
The subalpine belt extends to an altitude of 2300 m - shrub and tall grass meadow vegetation predominates. In the alpine belt, most of the mountain surface is devoid of vegetation or covered with crustose lichens. The upper zone is a belt of high-mountain rocky and glacial deserts, in which higher plants and animals are practically absent. The Alps are one of the most important recreational areas in Europe.
Changing nature by man
Over the course of historical time, the natural conditions of the continent have been changed by man. In many areas, natural vegetation has been almost completely destroyed and replaced by cultivated vegetation. The steppe and forest-steppe zones were especially affected.
In many cases, irreversible changes have occurred in nature, many species of plants and animals have been destroyed, and soils have been depleted. National parks, reserves and other protected areas were created to preserve nature.