West Siberian Plain The West Siberian Lowland is one of the largest low-lying accumulative plains in the world. It is located north of the low-hill plain of Kazakhstan and the Altai mountains, between the Urals in the west and the Central Siberian plateau in the east. Extending from north to south up to 2500 km, from W. to E. from 1000 to 1900 km; an area of about 2.6 million sq. km 2. The surface is flat, slightly dissected, with small height amplitudes. The heights of the lowlands of the northern and central regions do not exceed 50-150 m, low elevations (up to 220-300 m) are characteristic mainly of the western, southern, and eastern margins of the plain. A strip of hills also forms the so-called. Siberian Ridges, stretching in the middle part of the Z.-S. R. from the Ob almost to the Yenisei. Wide, flat spaces of interfluves predominate everywhere, with slight slopes of the surface, heavily waterlogged and in places complicated by moraine hills and ridges (in the north) or low sandy ridges (mainly in the south). Significant areas are occupied by flat ancient lake basins - woodlands. The river valleys form a relatively sparse network and in the upper reaches they are most often shallow hollows with poorly pronounced slopes. Only a few of the largest rivers flow in well-developed, deep (up to 50-80 m) valleys, with a steep right bank and a system of terraces on the left bank. Z.-S. R. formed within the epihercynian West Siberian plate, the basement of which is composed of intensely dislocated Paleozoic deposits. They are everywhere covered with a cover of loose marine and continental Meso-Cenozoic rocks (clays, sandstones, marls, etc.) with a total thickness of over 1000 m(in foundation depressions up to 3000-4000 m). The youngest Anthropogenic deposits in the south are alluvial and lacustrine, often covered by loess and loess-like loams; in the north - glacial, marine, and glacial-marine (capacity in places up to 200 m).
In the cover of loose deposits Z.-S. R. groundwater horizons are enclosed - fresh and mineralized (including brines), hot (up to 100-150 ° C) waters are also found (see West Siberian artesian basin). In the depths of Z.-S. R. the richest industrial deposits of oil and natural gas are enclosed (see the West Siberian oil and gas basin).
The climate is continental, quite severe. In winter, masses of cold continental air of temperate latitudes predominate over the plain, and in the warm season, an area of low pressure is formed and humid air masses from the North Atlantic often come here. The average annual temperatures are from -10.5°C in the north to 1-2°C in the south, the average temperatures in January are from -28 to -16°C, and in July from 4 to 22°C. The vegetation period in the extreme south reaches 175-180 days. The bulk of precipitation is brought by air masses from the west, mainly in July and August. Annual precipitation from 200-250 mm in tundra and steppe zones up to 500-600 mm in the forest zone. Snow cover thickness from 20-30 cm in the steppe up to 70-100 cm in the taiga of the Yenisei regions. The territory of the plain drains more than 2,000 rivers, the total length of which exceeds 250,000 km. km. The largest of them are the Ob, Yenisei, Irtysh. The main sources of river nutrition are melted snow water and summer-autumn rains; up to 70-80% of the annual runoff occurs in spring and summer. There are many lakes, the largest are Chany, Ubinskoye, and others. Some of the lakes in the southern regions are filled with salty and bitter-salty water. Large rivers are important navigable and rafting routes connecting the southern regions with the northern ones; The Yenisei, the Ob, the Irtysh, and the Tom have, in addition, large reserves of hydropower resources. The flatness of the relief Z. - S. r. determines a distinct latitudinal geographic zonality. A specific feature of most zones of Western Siberia is excessive soil moisture and, as a consequence, the wide distribution of marsh landscapes, which give way to solonetzes and solonchaks in the south. The north of the plain is a tundra zone, in which arctic, moss, and lichen landscapes form on arctic tundra and tundra gley soils, and in the south, shrub tundra. To the south there is a narrow strip of forest-tundra, where on peaty-gley, gley-podzolic and marsh soils complex landscape complexes of shrub tundra, spruce-larch woodlands, sphagnum and lowland bogs are developed. Most of the Z.-S. R. refers to the forest (forest-marsh) zone, within which coniferous taiga prevails on podzolic soils, consisting of spruce, fir, cedar, pine, Siberian larch; only in the extreme south of the zone are taiga massifs replaced by a strip of small-leaved birch and aspen forests. The total forest area exceeds 60 million hectares. ha, wood reserves 9 billion. m 3, and its annual growth is 100 million. m 3. The forest zone is distinguished by the wide development of raised ridge-hollow sphagnum bogs, which in some places account for more than 50% of the area. Of the animals of the forest zone, the following are typical: brown bear, lynx, wolverine, marten, otter, Siberian weasel, sable, elk, Siberian roe deer, squirrel, chipmunk, muskrat, and other representatives of the fauna of the European-Siberian subregion of the Palearctic. To the south of the subzone of small-leaved forests, there is a forest-steppe zone, where leached and ordinary chernozems, meadow-chernozem, dark gray forest and marsh soils, solonetzes, solods . The extreme southern part of the Z. - S. p. It occupies the steppe zone, in the north of which until recently forb feather grass steppes predominated, and in the south - feather grass-fescue steppes. Now these steppes, with their fertile chernozem and dark chestnut soils, have been plowed up, and only areas with saline soils in places have retained their virgin character. Lit.: West Siberian lowland. Essay on nature, M., 1963; Western Siberia, M., 1963. N. I. Mikhashov.
Great Soviet Encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .
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Between the Urals in the west and the Central Siberian Plateau in the east. OK. 3 million km². The length from north to south is up to 2500 km, from west to east up to 1900 km. Height from 50 150 m in the northern and central parts to 300 m in the western, southern and ... ... Big Encyclopedic Dictionary
WESTERN SIBERIAN PLAIN, between the Urals in the west and the Central Siberian Plateau in the east. OK. 3 million km2. The length from north to south is up to 2500 km, from west to east up to 1900 km. Height from 50 150 m in the northern and central parts to 300 m in ... ... Russian history
One of the largest on earth. Takes b. h. Zap. Siberia, stretching from the coast of the Kara Sea in the north to the Kazakh uplands in the south, from the Urals in the west to the Central Siberian Plateau in the east. OK. 3 million km². Wide flat or ... Geographic Encyclopedia
Between the Urals in the west and the Central Siberian Plateau in the east About 3 million km2. The length from north to south is up to 2500 km, from west to east up to 1900 km. Height from 50 150 m in the northern and central parts to 300 m in the western, southern and eastern. ... ... encyclopedic Dictionary
West Siberian Plain- West Siberian Plain, West Siberian Lowland. One of the largest low-lying accumulative plains of the globe. It occupies most of Western Siberia, stretching from the coast of the Kara Sea in the north to the Kazakh uplands and ... Dictionary "Geography of Russia"
Features of the geographical position of Western Siberia
Remark 1
To the east of the Ural Mountains lie vast expanses of the Asian part of Russia. This territory has long been called Siberia. But due to the diversity of the tectonic structure, this territory was divided into several separate regions. One of them is Western Siberia.
The basis of Western Siberia is the West Siberian Plain. It is bounded in the west by the Ural Mountains, and in the east by the Yenisei River. In the north, the plain is washed by the waters of the seas of the Arctic Ocean. The southern borders approach the Kazakh uplands and the Turgai plateau. The total area of the plain is about $3$ million km$²$.
The characteristic features of the West Siberian Plain are the following features:
- insignificant fluctuation of heights in such a vast territory;
- the length from north to south and an almost flat relief led to a clear change in natural zones with latitude (classical latitudinal zonality);
- formation of the largest swamp areas in the taiga and salt accumulation landscapes in the steppe zone;
- a transitional climate is formed from the temperate continental of the Russian Plain to the sharply continental of Central Siberia.
The history of the formation of the plain
The West Siberian Lowland lies on the Upper Paleozoic Plate. Sometimes this tectonic structure is also called epihercynian. The crystalline basement of the slab contains metamorphosed rocks. The foundation sinks towards the center of the slab. The total thickness of the sedimentary cover exceeds $4$ km (up to $6-7$ km in some areas).
As already mentioned, the foundation of the slab was formed as a result of the Hercynian orogeny. Further there was a peneplenization (leveling of a relief by means of erosive processes) of the ancient mountainous country. In the Paleozoic and Mesozoic, troughs form in the center, and the foundation was flooded by the sea. Therefore, it is covered with a significant thickness of Mesozoic deposits.
Later, during the era of the Caledonian folding, the southeastern part of the plain rose from the bottom of the sea. In the Triassic and Jurassic, the processes of relief denudation and the formation of a sedimentary rock mass predominated. Sedimentation continued into the Cenozoic. During the Ice Age, the north of the plain was under the thickness of the glacier. After its melting, a significant area of Western Siberia was covered with moraine deposits.
Characteristics of the relief of Western Siberia
As already noted, the geological history determined the formation of a flat relief on the territory of the West Siberian Plain. But a more detailed study of the physical and geographical features of the region showed that the orography of the territory is complex and diverse.
Large relief elements on the territory of the plain are:
- lowlands;
- sloping plains;
- hills;
- plateau.
In general, the West Siberian Plain has the form of an amphitheater, open to the Arctic Ocean. Plateau and upland areas dominate in the western, southern and eastern periphery. Lowlands prevail in the central regions and in the north. The lowlands are represented by:
- Kandinsky;
- Nizhneobskaya;
- Nadymskaya;
- Purskoy.
Among the plateau, the Ob plateau stands out. And the elevations are presented:
- Severo-Sosvinskaya;
- Turin;
- Ishimskaya;
- Chulym-Yenisei and others.
In the relief, there are zones of glacial-marine and permafrost-solifluction processes (tundra and northern taiga), fluvioglacial forms of lacustrine-glacial plains (up to middle taiga), and a zone of semiarid structural-denudation plateaus with erosion processes.
Remark 2
Currently, human economic activity plays an important relief-forming role. The development of Western Siberia is accompanied by the development of minerals. This causes changes in the structure of rock layers and changes the course of physical and geographical processes. erosion processes are intensifying. In the south, during the development of agriculture, a large amount of minerals is introduced into the soil. Chemical erosion develops. It is necessary to take a balanced approach to the development of the nature of Siberia.
The West Siberian Plain is one of the largest flat areas in the world, covering approximately 80% of Western Siberia.
Features of nature
In terms of total area, the West Siberian Plain is surpassed only by the Amazonian. The plain stretches from the coast of the Kara Sea south to the north of Kazakhstan. The total area of the West Siberian Plain is about 3 million square kilometers. km 2. Predominantly wide gently sloping and flat interfluves, which separate terraced valleys, prevail here.
The altitude amplitudes of the plain range on average between 20 and 200 m above sea level, but even the highest points reach 250 m.
On the lands of the West Siberian Plain, a continental climate dominates, the level of precipitation here is different: in the tundra and steppe regions - about 200 mm per year, in the taiga area it increases to 700 mm. General average temperatures - - 16°C in winter, + 15°C in summer.
Large full-flowing rivers flow on the territory of the plain, in particular the Yenisei, Taz, Irtysh and Ob. There are also very large lakes (Ubinskoye, Chany), and many smaller ones, some of them are salty. Some regions of the West Siberian Plain are characterized by wetlands. The center of the northern part is continuous permafrost. Solonchaks and solonetzes are common in the extreme south of the plain. The western-northern territory in all respects corresponds to the temperate zone - forest-steppe, steppe, taiga, deciduous forests.
Flora of the West Siberian Plain
The flat relief significantly contributes to zoning in the distribution of vegetation cover. The zonality of this territory has significant differences in comparison with similar zones in Eastern Europe. Due to difficulties in runoff, lichens, mosses and shrubs grow predominantly in wetlands in the north of the plains. Southern landscapes are formed under the influence of groundwater with a high level of salinity.
About 30% of the area of the plain is occupied by massifs of coniferous trees, many of which are swampy. Smaller areas are covered with dark coniferous taiga - spruces, firs and cedars. Occasionally, broad-leaved tree species are found in the southern regions. In the southern part there are very common birch forests, many of which are secondary.
Fauna of the West Siberian Plain
More than 450 species of vertebrates live in the expanses of the West Siberian Plain, of which 80 species belong to mammals. Many species are protected by law, as they belong to the category of rare and endangered. Recently, the fauna of the plain has been significantly enriched with acclimatized species - muskrat, hare, teleutka squirrel, American mink.
In reservoirs live mainly carp and bream. In the eastern part of the West Siberian Plain, some eastern species are found: chipmunk, Dzungarian hamster, etc. In most cases, the fauna of this territory is not much different from the animal world of the Russian Plain.
one of the largest on earth. Takes b. h. Zap. Siberia, stretching from the coast of the Kara Sea in the north to the Kazakh uplands in the south, from the Urals in the west to the Central Siberian Plateau in the east. OK. 3 million km². Wide flat or gently sloping interfluves, separated by terraced valleys, predominate. Height amplitudes from 20 to 200 m (max. up to 300 m). In the north, moraine hills and ridges are combined with young marine and alluvial (river) plains; in the south, lacustrine and lacustrine-alluvial plains are interspersed with ridges ( Barabinskaya, Kulunda Plain ). Z.-S. R. covers a thick cover of sedimentary rocks, which contain large accumulations of oil and gas. The climate is continental, precipitation from 200 (tundra, steppes) to 600 (taiga) mm per year. dense river network Ob , Irtysh , Yenisei , Taz and their tributaries). many large ( vats , Ubinskoe etc.) and countless small lakes, incl. salty. Extensive marshes and swampy forests. The north is continuous, with insular permafrost in the center. In the extreme south there are solonetzes and solonchaks. On W.-S. R. all zones and subzones of the temperate zone are represented: tundra, forest-tundra, taiga, deciduous forests, forest-steppe, steppe.
Dictionary of modern geographical names. - Yekaterinburg: U-Factoria. Under the general editorship of Acad. V. M. Kotlyakova. 2006 .
West Siberian Plain
(West Siberian lowland), in the north of Eurasia, between the Kazakh hills and Altai in the south, the Urals in the west, the coast of the Kara Sea in the north and the Central Siberian plateau in the east. Almost entirely within Russia, partly in Kazakhstan. One of the greatest low-lying plains of the globe. Length from north to south approx. 2500 km, from west to east up to 1900 km; sq. OK. 3 million km². At the base of the deep A folded Paleozoic basement occurs at 1000–4000 m. On it is a cover of loose sedimentary rocks of the Mesozoic and Cenozoic, which contain fresh and mineralized, including hot, groundwater. It also contains colossal reserves of oil and natural gas, which are being developed in West Siberian oil and gas province. Most of the plain does not rise above 150 m above sea level. m., max. high (more than 300 m) are confined to the foothills of the Urals and Altai. To the center. parts of the plain in latitude extend Siberian Ridges(height up to 285 m). Parts with their own names stand out: relatively elevated "continents" - Belogorsk, Tobolsk; relatively lowered steppes - Ishim, Baraba; plains - Vasyugan and others. Significant ter. has an almost perfectly flat relief, especially within wide interfluves. In the north it is complicated by moraine hills and ridges, in the south by low parallel ridges. The climate is continental, subarctic in the north. Wed January temperatures vary depending on latitude from -28 to -16 ° C, July - from 4 to 22 ° C. Precipitation falls from 200 to 600 mm per year. All in. permafrost is common in the districts. Ch. river Ob, its tributaries drain most of the plain. Other rivers include the Pur and Taz in the north, and the left tributaries of the Yenisei in the east. there is an empty area. Up to 70% ter. the plains are swampy. Associated with this is the formation of numerous small lakes in the north, including those of thermokarst origin. Relatively large lakes are concentrated in the south (Chany, Ubinskoye, and others). On the West Siberian Plain, the law of latitudinal geographical zonality is classically expressed. The north belongs to the subarctic zone, dominated by landscapes of moss, lichen and shrub tundra. To the south it is replaced by a narrow strip of forest-tundra, beyond which begins the taiga of spruce, fir, cedar, pine and larch, which occupies most of the plain. The taiga is replaced by small-leaved forests of birch and aspen, then the forest-steppe begins with copses (chops), turning into the steppe. Southern districts in the main. plowed up. Nature is protected in the reserves: Verkhne-Tazovsky, Visimsky, Gydansky, Malaya Sosva, Central Siberian and Yugansky.
Geography. Modern illustrated encyclopedia. - M.: Rosman. Under the editorship of prof. A. P. Gorkina. 2006 .
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Between the Urals in the west and the Central Siberian Plateau in the east. OK. 3 million km². The length from north to south is up to 2500 km, from west to east up to 1900 km. Height from 50 150 m in the northern and central parts to 300 m in the western, southern and ... ... Big Encyclopedic Dictionary
WESTERN SIBERIAN PLAIN, between the Urals in the west and the Central Siberian Plateau in the east. OK. 3 million km2. The length from north to south is up to 2500 km, from west to east up to 1900 km. Height from 50 150 m in the northern and central parts to 300 m in ... ... Russian history
Between the Urals in the west and the Central Siberian Plateau in the east About 3 million km2. The length from north to south is up to 2500 km, from west to east up to 1900 km. Height from 50 150 m in the northern and central parts to 300 m in the western, southern and eastern. ... ... encyclopedic Dictionary
The West Siberian Lowland is one of the largest low-lying accumulative plains in the world. It is located to the north of the low-hill plain of Kazakhstan and the Altai mountains, between the Urals in the west and the Central Siberian plateau in the east. Extending from N ... Great Soviet Encyclopedia
West Siberian Plain, West Siberian Lowland. One of the largest low-lying accumulative plains of the globe. It occupies most of Western Siberia, stretching from the coast of the Kara Sea in the north to the Kazakh uplands and ... Dictionary "Geography of Russia"
WESTERN SIBERIAN PLAIN, The West Siberian Lowland, one of the largest plains in the world (the third largest after the Amazonian and East European plains), in northern Asia, in Russia and Kazakhstan. It occupies the whole of Western Siberia, stretching from the coast of the Arctic Ocean in the north to the Turgai plateau and the Kazakh uplands in the south, from the Urals in the west to the Central Siberian plateau in the east. The length from north to south is up to 2500 km, from west to east from 900 km in (north) to 2000 (in south). The area is about 3 million km 2, including 2.6 million km 2 in Russia. The prevailing heights do not exceed 150 m. The lowest parts of the plain (50–100 m) are located mainly in its central (Kondinskaya and Sredneobskaya lowlands) and northern (Nizhneobskaya, Nadymskaya and Purskaya lowlands) parts. The highest point of the West Siberian Plain - up to 317 m - is located on the Priobsky Plateau.
At the base of the West Siberian Plain lies West Siberian platform. To the east it borders on Siberian platform, in the south - with Paleozoic structures of Central Kazakhstan, the Altai-Sayan region, in the west - with the folded system of the Urals.
Relief
The surface is a low accumulative plain with a rather uniform relief (more uniform than that of the East European Plain), the main elements of which are wide flat interfluves and river valleys; various forms of manifestation of permafrost (common to 59 ° N), increased waterlogging, and developed (mainly in the south in loose rocks and soils) ancient and modern salt accumulation are characteristic. In the north, in the area of distribution of marine accumulative and moraine plains (Nadymskaya and Purskaya lowlands), the general flatness of the territory is disturbed by moraine gently sloping and hilly-sloping (North Sosvinskaya, Lyulimvor, Verkhne-, Srednetazovsky, etc.) uplands 200–300 m high, the southern boundary of which runs around 61–62 ° N. sh.; they are horseshoe-shaped covered from the south by flat-topped uplands, among which are the Poluyskaya Upland, Belogorsky Mainland, Tobolsky Mainland, Siberian Uvaly (245 m), etc. In the north, permafrost exogenous processes (thermal erosion, heaving of soils, solifluction) are widespread, deflation is common on sandy surfaces, in swamps - peat accumulation. Permafrost is ubiquitous on the Yamal, Tazovsky, and Gydansky peninsulas; the thickness of the frozen layer is very significant (up to 300–600 m).
To the south, the area of moraine relief is adjoined by flat lacustrine and lacustrine-alluvial lowlands, the lowest (40–80 m high) and swampy of which are the Konda lowland and the Sredneobskaya lowland with the Surgut lowland (105 m high). This territory, not covered by Quaternary glaciation (to the south of the line Ivdel - Ishim - Novosibirsk - Tomsk - Krasnoyarsk), is a poorly dissected denudation plain, rising up to 250 m to the west, to the foothills of the Urals. In the interfluve of the Tobol and the Irtysh, there is an inclined, in places with ridges, lacustrine-alluvial Ishim Plain(120–220 m) with a thin cover of loess-like loams and loess occurring on salt-bearing clays. It is adjacent to alluvial Baraba lowland, Vasyugan Plain and Kulunda Plain, where the processes of deflation and modern salt accumulation are developed. In the foothills of Altai - the Ob plateau and the Chulym plain.
On the geological structure and minerals, see Art. West Siberian platform ,
Climate
The West Siberian Plain is dominated by a harsh continental climate. The significant length of the territory from north to south determines the well-defined latitudinal zonality of the climate and noticeable differences in the climatic conditions of the northern and southern parts of the plain. The nature of the climate is significantly influenced by the Arctic Ocean, as well as the flat relief, which contributes to the unhindered exchange of air masses between north and south. Winter in the polar latitudes is severe and lasts up to 8 months (the polar night lasts almost 3 months); the average January temperature is from -23 to -30 °C. In the central part of the plain, winter lasts almost 7 months; the average January temperature is from -20 to -22 °C. In the southern part of the plain, where the influence of the Asian anticyclone is increasing, at the same average monthly temperatures, winter is shorter - 5–6 months. Minimum air temperature -56 °C. The duration of snow cover in the northern regions reaches 240–270 days, and in the southern regions - 160–170 days. The thickness of the snow cover in the tundra and steppe zones is 20–40 cm; in the forest zone, from 50–60 cm in the west to 70–100 cm in the east. In summer, the western transfer of Atlantic air masses predominates with intrusions of cold Arctic air in the north, and dry warm air masses from Kazakhstan and Central Asia in the south. In the north of the plain, summer, which occurs under polar day conditions, is short, cool, and humid; in the central part - moderately warm and humid, in the south - arid and dry with dry winds and dust storms. The average July temperature rises from 5°C in the Far North to 21–22°C in the south. The duration of the growing season in the south is 175–180 days. Atmospheric precipitation falls mainly in summer (from May to October - up to 80% of precipitation). Most precipitation - up to 600 mm per year - falls in the forest zone; the wettest are the Kondinskaya and Sredneobskaya lowlands. To the north and south, in the tundra and steppe zone, the annual precipitation gradually decreases to 250 mm.
surface water
On the territory of the West Siberian Plain, more than 2,000 rivers flow, belonging to the basin of the Arctic Ocean. Their total flow is about 1200 km 3 of water per year; up to 80% of the annual runoff occurs in spring and summer. The largest rivers - the Ob, Yenisei, Irtysh, Taz and their tributaries - flow in well developed deep (up to 50–80 m) valleys with a steep right bank and a system of low terraces on the left bank. The feeding of the rivers is mixed (snow and rain), the spring flood is extended, the low water is long summer-autumn and winter. All rivers are characterized by slight slopes and low flow rates. The ice cover on the rivers lasts up to 8 months in the north, up to 5 months in the south. Large rivers are navigable, are important rafting and transportation routes, and, in addition, have large reserves of hydropower resources.
There are about 1 million lakes on the West Siberian Plain, the total area of which is more than 100 thousand km2. The largest lakes are Chany, Ubinskoye, Kulundinskoye, and others. Lakes of thermokarst and moraine-glacial origin are widespread in the north. There are many small lakes in suffusion depressions (less than 1 km 2): on the interfluve of the Tobol and Irtysh - more than 1500, on the Baraba lowland - 2500, among them there are many fresh, salty and bitter-salty ones; there are self-sustaining lakes. The West Siberian Plain is distinguished by a record number of swamps per unit area (the area of the wetland is about 800 thousand km 2).
Landscape types
The uniformity of the relief of the vast West Siberian Plain determines the clearly pronounced latitudinal zonality of landscapes, although, compared with the East European Plain, the natural zones here are shifted to the north; landscape differences within the zones are less noticeable than on the East European Plain, and the zone of broad-leaved forests is absent. Due to the poor drainage of the territory, hydromorphic complexes play a prominent role: swamps and swampy forests occupy about 128 million hectares here, and in the steppe and forest-steppe zones there are many solonetzes, solods and solonchaks.
On the Yamal, Tazovsky and Gydansky peninsulas, in conditions of continuous permafrost, landscapes of arctic and subarctic tundra with moss, lichen and shrubs (dwarf birch, willow, alder) vegetation have formed on gleyzems, peat-gleyzems, peat-podburs and soddy soils. Polygonal grass-hypnum swamps are widespread. The share of primary landscapes is extremely insignificant. To the south, tundra landscapes and swamps (mostly flat-hummocky) are combined with larch and spruce-larch light forests on podzolic-gley and peat-podzolic-gley soils, forming a narrow forest-tundra zone, transitional to the forest (forest-bog) zone of the temperate zone, represented by subzones of the northern, middle and southern taiga. Swampiness is common to all subzones: over 50% of the area of the northern taiga, about 70% of the middle taiga, and about 50% of the southern taiga. The northern taiga is characterized by flat and large-hummocky raised bogs, the middle taiga is characterized by ridge-hollow and ridge-lake bogs, the southern taiga is characterized by ridge-hollow, pine-shrub-sphagnum, transitional sedge-sphagnum and lowland tree-sedge bogs. The largest swamp Vasyugan Plain. The forest complexes of different subzones, formed on slopes with different degrees of drainage, are peculiar.
Northern taiga forests on permafrost are represented by sparse, low-growing, heavily waterlogged, pine, pine-spruce and spruce-fir forests on gley-podzolic and podzolic-gley soils. The indigenous landscapes of the northern taiga occupy 11% of the plain area. Indigenous landscapes in the middle taiga occupy 6% of the area of the West Siberian Plain, in the southern - 4%. Common to the forest landscapes of the middle and southern taiga is the wide distribution of lichen and shrub-sphagnum pine forests on sandy and sandy loamy illuvial-ferruginous and illuvial-humus podzols. On loams in the middle taiga, along with extensive swamps, spruce-cedar forests with larch and birch forests are developed on podzolic, podzolic-gley, peat-podzolic-gley and gley peat-podzols.
In the southern taiga subzone on loams - spruce-fir and fir-cedar (including urman - dense dark coniferous forests with a predominance of fir) small-grass forests and birch forests with aspen on sod-podzolic and sod-podzolic-gley (including with a second humus horizon) and peat-podzolic-gley soils.
The subtaiga zone is represented by park pine, birch and birch-aspen forests on gray, gray gley and soddy-podzolic soils (including those with a second humus horizon) in combination with steppe meadows on cryptogley chernozems, solonetsous in places. Indigenous forest and meadow landscapes are practically not preserved. Boggy forests turn into lowland sedge-hypnum (with ryams) and sedge-reed bogs (about 40% of the zone). For forest-steppe landscapes, inclined plains with lusk-shaped and lusse covers on saline tertiary clay are typical of birch and aspen-blessed heaps on gray soils and malt in a complex with multi-grass-green spanteen meadows on leafered and crypto-warmed blacksmanships, south-with meadow steps mi on ordinary chernozems, in places solonetzic and saline. On the sands are pine forests. Up to 20% of the zone is occupied by eutrophic reed-sedge bogs. In the steppe zone, the primary landscapes have not been preserved; in the past, these were forb-feather grass steppe meadows on ordinary and southern chernozems, sometimes saline, and in the drier southern regions - fescue-feather grass steppes on chestnut and cryptogley soils, gley solonetzes and solonchaks.
Environmental issues and protected natural areas
In areas of oil production due to pipeline breaks, water and soil are polluted with oil and oil products. In forestry areas - overcutting, waterlogging, the spread of silkworms, fires. In agricultural landscapes, there is an acute problem of lack of fresh water, secondary salinization of soils, destruction of soil structure and loss of soil fertility during plowing, drought and dust storms. In the north, there is degradation of reindeer pastures, in particular due to overgrazing, which leads to a sharp reduction in their biodiversity. No less important is the problem of preserving hunting grounds and habitats of fauna.
Numerous reserves, national and natural parks have been created to study and protect typical and rare natural landscapes. Among the largest reserves: in the tundra - the Gydansky reserve, in the northern taiga - the Verkhnetazovsky reserve, in the middle taiga - the Yugansky reserve and Malaya Sosva, etc. The national park Pripyshminsky Bory was created in the subtaiga. Natural parks are also organized: in the tundra - Deer streams, in the north. taiga - Numto, Siberian Ridges, in the middle taiga - Kondinsky lakes, in the forest-steppe - Bird's harbor.
The first acquaintance of Russians with Western Siberia took place, probably, as early as the 11th century, when the Novgorodians visited the lower reaches of the Ob River. With the campaign of Yermak (1582–85), a period of discoveries began in Siberia and the development of its territory.
