Video lesson “Western Siberia. Geographical location, main features of nature” will introduce you to the West Siberian economic region. From the lesson you will learn about the administrative-territorial composition of the district, its geographical and economic-geographical position. In addition, the teacher will tell in detail about the unique nature and resources of Western Siberia.

The population of the region is 16.7 million people;

The area of ​​the district is 2,427 thousand square meters. km.

Rice. 1. West Siberian economic region ()

Features of the economic and geographical position of the region:

1. Relative proximity to the developed regions of the European part of Russia

2. Proximity to resources

3. Transit position

4. Availability of access to the sea (and the Northern Sea Route)

The West Siberian economic region occupies a vast area to the east of the Ural Mountains, extending almost to the Yenisei. But the extension from north to south is especially great. In the west, the region borders on the Northern and Ural economic regions, in the south - on Kazakhstan, China and Mongolia, in the north - has access to the Kara Sea, in the east - the East Siberian economic region.

Climate and nature of Western Siberia.

Most of the territory of the region is occupied by the West Siberian Plain. In the southeast is the Altai mountain system - the highest part of Western Siberia (Belukha Mountain - 4506 meters). Most of Western Siberia is located within the continental climate of the temperate zone, and its northern part is located within the subarctic and arctic zones, so its climate is continental. Western Siberia covers five natural zones: tundra, forest-tundra, taiga, forest-steppe and steppe. Most of Western Siberia is swampy, here is the largest swamp area in the world.

Rice. 2. Swamps of Western Siberia (Vasyuganye) ()

In the south of the region there is the Trans-Siberian Railway, which crosses the largest Siberian rivers (Ob, Irtysh). The largest lake in the region is Chany. A significant part of the territory is within the permafrost.

Rice. 3. The Ob River in Barnaul

Natural resources of Western Siberia.

Western Siberia is rich in minerals - oil, gas, coal, and ores. The area of ​​promising oil and gas bearing territories is estimated at more than 1.7 million km 2 . the main deposits are confined to the Middle Ob (Samotlor, Megionskoye and others in the Nizhnevartovsk region; Ust-Balykskoe, Fedorovskoye and others in the Surgut region). Deposits of natural gas in the polar region - Medvezhye, Urengoy and others, in the Arctic - Yamburgskoye, Ivankovskoye and others. New fields discovered on the Yamal Peninsula. There are oil and gas resources in the Urals.

Rice. 4. Gas pipeline "Yamal-Europe" ()

Gas fields were discovered in the Vasyugansk region. In general, more than 300 oil and gas fields have been discovered in Western Siberia.

The area is also rich in coal. Its main resources are located in Kuzbass (Kemerovo Region), whose reserves are estimated at 600 billion tons. About 30% of Kuznetsk coals are coking. Coal seams are very thick and lie close to the surface, which makes it possible, along with the mine method, to conduct open-pit mining. The western wing of the Kansk-Achinsk brown coal basin is located in the northeast of the Kemerovo region.

The ore base of Western Siberia is also large. There are reserves of soda and other salts in Western Siberia in the lakes of the Kulunda steppe. Novosibirsk and Kemerovo regions are rich in limestone. Western Siberia has thermal iodine-bromine springs. Altai is rich in building materials.

The vast majority of the forest resources of the region are concentrated in the zone of the West Siberian taiga, and the rest is approximately equally distributed between the Altai Territory and the Kemerovo Region, where mountain forests predominate. In addition, Western Siberia is rich in water resources and chernozem soils.

Homework:

1. Name and find on the map the subjects of the Federation of the West Siberian economic region.

2. What is the peculiarity of the nature of Western Siberia? Give examples of natural areas of the region.

Bibliography

Main

1. Geography of Russia. population and economy. Grade 9: textbook for general education. uch. / V. P. Dronov, V. Ya. Rom. - M.: Bustard, 2011. - 285 p.

2. Geography. Grade 9: atlas. - 2nd ed., corrected. - M.: Bustard; DIK, 2011 - 56 p.

Additional

1. Economic and social geography of Russia: Textbook for universities / Ed. prof. A. T. Khrushchev. - M.: Bustard, 2001. - 672 p.: ill., cart.: tsv. incl.

Encyclopedias, dictionaries, reference books and statistical collections

1. Geography: a guide for high school students and university applicants. - 2nd ed., corrected. and dorab. - M.: AST-PRESS SCHOOL, 2008. - 656 p.

Literature for preparing for the GIA and the Unified State Examination

1. Control and measuring materials. Geography: Grade 9 / Comp. E. A. ZHIZHINA - M.: VAKO, 2012. - 112 p.

2. Thematic control. Geography. Nature of Russia. Grade 8 / N. E. Burgasova, S. V. Bannikov: textbook. - M.: Intellect-Centre, 2010. - 144 p.

3. Tests in geography: grades 8-9: to the textbook, ed. V. P. Dronova “Geography of Russia. Grades 8-9: a textbook for educational institutions ”/ V. I. Evdokimov. - M.: Exam, 2009. - 109 p.

Http://ru.wikipedia.org/wiki/%C7%E0%EF%E0%E4%ED%EE-%D1%E8%E1%E8%F0%F1%EA%E8%E9_%FD%EA% EE%ED%EE%EC%E8%F7%E5%F1%EA%E8%E9_%F0%E0%E9%EE%ED

The West Siberian Plain, which occupies about 3 million sq. km 2, is one of the greatest plains of the globe: in size it can only be compared with the Amazonian lowland.

The boundaries of the lowland are clearly defined natural boundaries: in the north - the coastline of the Kara Sea, in the south - the Turgai Tableland, the foothills of the Kazakh hills, Altai, Salair and Kuznetsk Alatau, in the west - the eastern foothills of the Urals, in the east - the valley of the river. Yenisei. The orographic boundaries of the lowland coincide with the geological ones, which are considered to be outcrops in some places along the edges of the lowland of dislocated Paleozoic and older rocks, for example, in the south, near the Kazakh hills. In the Turgai trough, which connects the West Siberian lowland with the plains of Central Asia, the boundary is drawn along the Kustanai swell, where the pre-Mesozoic basement lies at a depth of 50-150 m from the surface. The length of the plain from north to south - 2500 km. The largest width - 1500 km- it reaches in the southern part. In the north of the lowland, the distance between the western and eastern points is about 900-950 km. Almost the entire territory of the lowland is located within the RSFSR - the Yamalo-Nenets and Khanty-Mansiysk national districts, in the regions - Kurgan, Sverdlovsk, Tyumen, Omsk, Novosibirsk, Tomsk, Kemerovo; in the regions - Altai and Krasnoyarsk. The southern part belongs to the Kazakh SSR - to the regions of the Virgin Territory - Kustanai, North Kazakhstan, Kokchetav, Tselinograd, Pavlodar and Semipalatinsk.

Relief and geological structure. The relief of the West Siberian Plain is characterized by complexity and diversity. Over a long distance, the fluctuations in altitude are insignificant. Maximum marks (250-300 m) concentrated in the western part of the plain - in the Urals. The southern and eastern parts of the plain are also elevated compared to the central one. In the south, heights reach 200-300 m. In the central part of the plain, the absolute marks on the watersheds are about 50-150 m, and in the valleys - less than 50 m; For example, in the river valley Ob, at the mouth of the river. Wah, altitude 35 m, and near the city of Khanty-Mansiysk - 19m.

On the peninsulas, the surface rises: absolute marks on the Gydan Peninsula reach 150-183 m, and on Tazovsky - about 100m.

In general orographic terms, the West Siberian Plain has a concave shape with raised edges and a lowered central part. Along its outskirts there are hills, plateaus and sloping plains, descending towards its central parts. Among them, the largest are: the North Sosva, Tobolsk-Tavda, Ishim, Ishim-Irtysh and Pavlodar sloping plains, Vasyugan, Ob ​​and Chulym-Yenisei plateaus, Vakh-Ket and Srednetazovsky uplands, etc.

To the north of the latitudinal flow of the Ob, from the Urals to the Yenisei, one hill after another extends, forming a single orographic axis of the West Siberian Plain - the Siberian Uvals, along which the Ob-Taz and Ob-Pur watersheds pass. All large lowlands are concentrated in the central parts of the plain - Khanty-Mansiysk, Surgut woodland, Sredneobskaya, Purskaya, Khetskaya, Ust-Obskaya, Barabinskaya and Kulundinskaya.

The flatness of the territory was created by a long geological history in the pre-Quaternary time. The entire West Siberian Plain is located in the area of ​​Paleozoic folding and represents in tectonic terms the West Siberian plate of the Ural-Siberian epi-Hercynian platform. The folded structures that were on the site of the West Siberian Plain, as a result of tectonic movements, sank to different depths either at the end of the Paleozoic or at the very beginning of the Mesozoic (in the Triassic).

Deep boreholes in various parts of the plain penetrated Cenozoic and Mesozoic rocks and reached the surface of the base plate at various depths: at the Makushkino railway station (half the distance between Kurgan and Petropavlovsk) - at a depth of 693 m(550 m from sea level), at 70 km east of Petropavlovsk - at 920 m(745 m from sea level), and in the city of Turgay - by 325 m. In the region of the eastern slope of the Severo-Sosvinsky arch, the Paleozoic basement was lowered to a depth of 1700-2200 m, and in the central part of the Khanty-Mansiysk depression - 3500-3700 m.

The subsided sections of the foundation formed syneclises and troughs. In some of them, the thickness of Mesozoic and Cenozoic loose deposits reaches more than 3000m 3.

In the north of the West Siberian Plate, in the interfluve of the rivers of the lower Ob and Taz, the Ob-Taz syneclise stands out, and in the south, along the course of the middle Irtysh, the Irtysh syneclise and in the region of Kulunda Lake, the Kulunda depression. In the north, plates in syneclises, according to the latest data,

the foundation goes to a depth of 6000 m, and in places - by 10,000 m. In anteclises, the foundation lies at a depth of 3000-4000 m from the surface.

According to the geological structure, the basement of the West Siberian Plate is apparently heterogeneous. It is assumed that it consists of folded structures of the Hercynian, Caledonian, Baikal and older ages.

Some large geological structures of the West Siberian Plate - syneclises and anteclises - in the relief of the plain correspond to elevated and low-lying areas. For example, the syneclise lowlands: the Baraba lowland corresponds to the Omsk depression, the Khanty-Mansiysk lowland was formed on the site of the Khanty-Mansiysk depression. Examples of anteclise elevations are: Lyulinvor and Verkhnetazovskaya. In the marginal parts of the West Siberian Plate, sloping plains correspond to monoclinal morphological structures, in which the general lowering of the topographic surface follows the subsidence of the basement into plate syneclises. Such morphostructures include the Pavlodar, Tobolsk-Tavda sloping plains, etc.

During the Mesozoic, the entire territory was a mobile land area, which experienced only epeirogenic fluctuations with a general tendency to subside, as a result of which the continental regime was replaced by a marine one. Thick layers of sediments accumulated in the sea basins. It is known that in the Upper Jurassic the sea occupied the entire northern part of the plain. In the Cretaceous period, many parts of the plains turned into dry land. This is evidenced by findings of the weathering crust and continental deposits.

The Upper Cretaceous sea was replaced by the Tertiary. The deposits of the Paleogene seas smoothed out the pre-Tertiary relief and created the ideal flatness of the West Siberian Plain. The sea reached its maximum development in the Eocene era: at that time it covered almost the entire area of ​​the West Siberian Plain and the connection of the sea basins of the Aral-Caspian depression with the West Siberian Plain was carried out through the Turgai Strait. During the entire Paleogene, there was a gradual subsidence of the plate, which reached its greatest depth in the eastern regions. This is evidenced by the thickness and nature of the Paleogene deposits increasing to the east: in the west, in the Cis-Urals, near the Kazakh uplands, sands, conglomerates and pebbles predominate. Here they are highly elevated and come to the surface or lie at shallow depths. Their thickness in the west reaches 40-100 m. To the east and north, sediments subside under Neogene and Quaternary deposits. So, for example, in the Omsk region, Paleogene deposits were discovered by boreholes at a depth of more than 300 m from the surface, and even deeper they lie to the north of the station. Tatar. Here they become thinner (clays, flasks). At the confluence of the river Irtysh in the river. Ob and north along the river. The Ob Paleogene layers rise again and emerge along the river valleys in natural outcrops.

After a long maritime regime, the primary accumulative plain rose by the beginning of the Neogene, and a continental regime was established on it. Judging by the nature of the occurrence of the Paleogene deposits, it can be said that the primary accumulative marine plain had a bowl-shaped relief structure: it was all lowered most in the central part. This structure of the surface to the beginning of the Neogene predetermined mainly the modern features of the relief of the West Siberian Plain. The land was covered during this period by numerous lakes and lush subtropical vegetation. This is evidenced by the wide distribution of exclusively continental deposits, consisting of pebbles, sand, sandy loam, loams and clays of lacustrine and river origin. The best sections of these deposits are known along the Irtysh, Tavda, Tura, and Tobol rivers. Remains of flora (marsh cypress, sequoia, magnolia, linden, walnut) and fauna (giraffes, camels, mastodons) are well preserved in the sediments, which indicates warmer climatic conditions in the Neogene compared to modern ones.

In the Quaternary period, a cooling of the climate occurred, which led to the development of an ice sheet in the northern half of the plain. The West Siberian Plain has experienced three ice sheets (Samarovskoe, Tazovskoe and Zyryanskoe). Glaciers descended to the plain from two centers: from the mountains of Novaya Zemlya, the Polar Urals and from the mountains of Byrranga and Putorana. The existence of two centers of glaciation in the West Siberian Plain is proved by the distribution of boulders. Boulder glacial deposits cover vast expanses of the plain. However, in the western part of the plain - along the lower reaches of the Irtysh and Ob rivers - boulders consist mainly of Ural rocks (granites, granodiorites), and in the eastern part - along the valleys of the Vakha, Ob, Bolshoy Yugan and Salym rivers, fragments of traps predominate in the interfluves of the Gydan Peninsula, brought from the northeast from the Taimyr center. The ice cover descended during the Samarovsk glaciation along the leveled surface to the south, to approximately 58 ° N. sh.

The southern edge of the glacier stopped the flow of pre-glacial rivers that directed their waters to the Kara Sea basin. Part of the river waters apparently reached the Kara Sea. At the southern edge of the glacier, lake basins arose, powerful fluvioglacial flows formed, flowing southwest, towards the Turgai Strait.

In the south of the West Siberian Plain, from the foothills of the Urals to the Irtysh, and in some places further to the east (Prichulym plateau), loess-like loams are common; they lie on the surface of interfluve plateaus, overlapping their bedrocks. It is assumed that the formation of loess-like loams is associated with eolian or eluvial processes, and possibly these are deltaic and coastal deposits of ancient seas.

In the interglacial periods, the northern part of the West Siberian Lowland was flooded with waters of boreal transgression, which penetrated along the valleys of large rivers - the Ob, Tazu, Puru, Yenisei, etc. Yenisei - up to 63 ° N. sh. The central part of the Gydan Peninsula was an island in the marine boreal basin.

The boreal sea was much warmer than the modern one, as evidenced by marine sediments formed by fine sandy loams and loams with the inclusion of heat-loving molluscs. They lie at an altitude of 85-95 m above present sea level.

The last glaciation in Western Siberia did not have a cover character. Glaciers descending from the Urals, Taimyr and the Norilsk Mountains ended not far from their centers. This is indicated by the location of their terminal moraines and the absence of moraine deposits of the last glaciation in the northern part of the West Siberian Plain. So, for example, marine

deposits of boreal transgression in the north of the lowland are nowhere covered by moraine.

In the distribution of various genetic types of relief over the territory, a successive change is observed when moving from north to south, which makes it possible to distinguish geomorphological zones.

1. The zone of the Pre-Karsky marine stepped accumulative plains occupies the entire coastal strip of the Kara Sea, extending deep into the interior of the mainland along the Ob, Taz and Yenisei bays. The plain is composed of marine clays and sands during the boreal transgression; it rises to a height of 80 m. Toward the coastline, the heights decrease, forming several sea terraces.

2. The zone of the Ob-Yenisei accumulative hilly and plane-undulating water-glacial plains is located between 70 and 57 ° N. t., from the Urals to the Yenisei. On the Gydan and Yamal peninsulas, it occupies inland areas, extending north of 70 ° N. sh., and in the Cis-Urals it descends south of 60 ° N. sh., in the basin of the river. Tavda. In the central regions, up to the southern boundary of the Samarovsk glaciation, this territory was covered with ice sheets. It is composed of boulder clays, boulder sands, and loams.

Prevailing heights above sea level - 100-200 m. The surface of the plain is flat-undulating, with moraine hills 30-40 m, with ridges and shallow lacustrine depressions, ridged relief and ancient runoff hollows. Large areas are occupied by outwash lowlands. Especially many lakes are found among the vast interfluve swamps of the Ob-Taz plain.

3. The zone of near-glacial water-accumulation plains is located south of the boundary of maximum glaciation and extends from the river. Tavda, south of the latitudinal segment of the Irtysh valley, to the river. Yenisei.

4. The zone of non-glacial flat and wavy-ravine erosion-accumulative plains includes the Ishim Plain, located in the basin of the river. Ishim, Baraba and Kulunda steppes. The main landforms were created by powerful water flows, which formed wide hollows of the ancient runoff in a southwestern direction, filled with alluvial deposits. The watershed near-glacial regions have a ridged relief. Manes height 5-10 m elongated mainly in the same direction as the hollows of the ancient runoff. They are especially pronounced in the Kulunda and Baraba steppes.

5. The zone of foothill denudation plains adjoins the mountain structures of the Urals, the Salair Ridge and the Kuznetsk Alatau. Piedmont plains are the most elevated parts of the territory of the West Siberian Plain; they are composed of deposits of the Mesozoic and Tertiary ages and are overlain by Quaternary loess-like eluvial-deluvial loams. The surfaces of the plains are dissected by wide erosional valleys. The watershed areas are flat, with closed basins, depressions, some of them contain lakes.

Thus, on the territory of the West Siberian Plain, geomorphological zoning is clearly revealed, which is due to the history of the development of the entire territory, especially during the Ice Age. Geomorphological zoning is predetermined by the activity of glaciers, Quaternary tectonic movements, and boreal transgression.

When comparing the geomorphological zones of the West Siberian and Russian plains, a general pattern is revealed, namely: both here and there

narrow strips of sea plains, an area of ​​glacial drift (located in the northwest and northeast), zones of glacial accumulation, stripes of woodlands and non-glacial zones are clearly visible. But on the Russian Plain, the non-glacial zone ends with sea plains, and on the West Siberian Plain, with a zone of foothill plains.

The valleys of the Ob and Irtysh rivers, reaching a width of 80-120 km, pass through all these geomorphological zones. Valleys cut through Quaternary and Tertiary deposits to a depth of 60-80 m. The floodplains of these rivers are 20-40 km have numerous meandering channels, oxbow lakes, coastal ridges. Terraces rise above the floodplains. Everywhere in the valleys there are two terraces of the accumulative-erosion type with a height of 10-15 and about 40 m. In the foothills, the valleys narrow, the number of terraces increases to six, their height increases to 120 m. The valleys have an asymmetric structure. On steep slopes, ravines and landslides are developed.

Minerals are concentrated in the primary and Quaternary deposits of the plain. The Jurassic deposits contain coal deposits explored in the southwestern part of the plain and in the Turgai plain. Brown coal deposits have been discovered in the Middle Ob basin. The Sredneobsky basin includes the Tomskoye, Prichulymskoye, Narymskoye and Tymskoye deposits. The Cretaceous deposits of the plain contain phosphorites and bauxites discovered in the northern part of the Turgai trough. Iron ore deposits have recently been discovered among the Cretaceous deposits in the south of the West Siberian Plain and in the northwestern part of the Turgai Trough, represented by oolitic iron ore. In recent years, on the territory of the West Siberian Plain, during deep drilling, iron ore deposits have been discovered on the left bank of the Ob, from the city of Kolpashevo to the village. Narym, and, moreover, in the basins of the Vasyugan, Keti and Tyma rivers. Iron ores contain iron - from 30 to 45%. Deposits of iron ore have been discovered in the Kulunda steppe (the region of Lake Kuchu k, Kulunda station, Klyuchi), they contain up to 22% iron. Large gas fields are known in the Tyumen region (Berezovskoye and Punginskoye). At the end of 1959, from a borehole laid on the bank of the river. Konda (near the village of Shaim), the first commercial oil in Western Siberia was obtained. In March 1961, a well was blocked in the center of the West Siberian Lowland, in the middle reaches of the river. Ob, near the village of Megion. Commercial oil is concentrated in the Lower Cretaceous deposits. Oil and gas fields are confined to the Jurassic and Cretaceous rocks. The Paleogene deposits of the southern part of the lowland and the Turgai trough have deposits of oolitic iron ores, lignites, and bauxites. Building materials are widespread throughout the territory - sands and clays of marine and continental origin (Mesozoic and Quaternary), peat bogs. The peat reserves are huge. The total volume of explored peatlands is more than 400 million hectares. m 2 air-dry peat. The average thickness of peat layers is 2.5-3 m. In some hollows of ancient runoff (Tym-Paiduginskaya and others), the thickness of peat layers reaches 5 - 6 m, In the lakes of the southern part there are large reserves of salts (table salt, mirabilite, soda).

Climate. The climate of the West Siberian Plain is formed as a result of the interaction of a number of factors, namely:

1) geographical location. The main part of the surface is located in temperate latitudes, and the peninsulas are located beyond the Arctic Circle.

The entire plain is thousands of kilometers away from the Pacific and Atlantic oceans. The large extent of the territory from north to south predetermines different amounts of total radiation, which significantly affects the distribution of air and ground temperatures. The total radiation increases when moving from north to south from 60 to 110 kcal / cm 2 per year and is distributed almost zonally. It reaches its greatest value at all latitudes in July (in Salekhard - 15.8 kcal / cm 2, in Pavlodar -16.7 kcal / cm 2). In addition, the position of the territory in temperate latitudes determines the inflow

air masses from the Atlantic Ocean under the influence of west-east transfer. The significant remoteness of the West Siberian Plain from the Atlantic and Pacific Oceans creates conditions above its surface for the formation of a continental climate;

2) pressure distribution. Areas of high (Asian anticyclone and Voeikov axis) and low pressure (over the Kara Sea and Central Asia) determine the strength of the wind, its direction and movement;

3) the relief of the marshy and concave plain, open to the Arctic Ocean, does not prevent the intrusion of cold arctic air masses. They freely penetrate to Kazakhstan, changing during their movement. The flatness of the territory contributes to the penetration of continental tropical air far to the north. Thus, meridional air circulation also occurs. The Ural Mountains have a significant impact on the amount and distribution of precipitation in the plain, since a significant part of it falls on the western slopes of the Urals? and the western air masses come to the West Siberian Plain already drier;

4) the properties of the underlying surface - a large forest cover, waterlogging and a significant number of lakes - have a significant impact on the distribution of a number of meteorological elements.

In winter, the entire area is very cold. To the east of the West Siberian Plain, a stable region of the Asian High is being formed. Its spur is the Voeikov axis, which stretches across the southern part of the plain from November to March. Above the Kara Sea, a depression of low pressure of the Icelandic Low extends: the pressure decreases from south to north - towards the Kara Sea. Therefore, south, southwest and southeast winds prevail.

Winter is characterized by stable negative temperatures. Absolute minima reach from -45 to -54°. January isotherms in the northern part of the plain have a meridional direction, but south of the Arctic Circle (about 63-65 Q with. sh.) - southeast.

The isotherm is -15° in the south, and -30° in the northeast. The western part of the plain is warmer than the eastern part by 10°. This is explained by the fact that the western parts of the territory are under the influence of western air masses, while in the east the territory is cooled by the action of the Asian anticyclone.

Snow cover in the north appears in the first decade of October and stays on the peninsulas for about 240-260 days. At the end of November, almost the entire territory is covered with snow. In the south, snow lasts up to 160 days and usually melts at the end of April, and in the north - at the end of June (20/VI).

In summer, over the whole of Asia, as well as over the territory of the West Siberian Plain, the pressure is lowered, therefore Arctic air freely penetrates into its territory. When moving south, it warms up and is additionally moistened due to local evaporation. But the air warms up faster than it gets humidified, which causes a decrease in its relative humidity. The warmer western air masses arriving on the West Siberian Plain are more transformed along the way than the Arctic ones. Intensive transformation of both Arctic and Atlantic air masses leads to the fact that the territory of the lowland is filled with dry continental temperate air, which has a high temperature. Cyclonic activity develops most intensively in the northern part of the plain, due to the intensification of temperature differences between cold arctic and warm continental air, i.e., on the arctic front line. In the middle and southern parts of the plain, cyclonic activity is weakened, but cyclones still penetrate here from the European territory of the USSR.

The average July isotherms run almost in the latitudinal direction. In the far north, through about. Bely, the isotherm + 5 ° passes, the isotherm + 15 ° goes south of the Arctic Circle, the isotherm + 20, + 22 ° stretches through the steppe regions with a deviation to the southeast - towards Altai. The absolute maximum in the north reaches +27°, and in the south +41°. Thus, when moving from north to south, changes in summer temperatures are more significant compared to winter ones. The growing season, due to the temperature regime, also changes when moving from north to south: in the north it reaches 100 days, and in the south - 175 days.

Precipitation is distributed unevenly over the territory and over the seasons. Most rainfall - 400 to 500 mm- drops out in the middle strip of the plain. To the north and south, the amount of precipitation decreases markedly (up to 257 mm - on Dixon Island and 207 mm- in Semipalatinsk). The greatest amount of precipitation falls throughout the plain from May to October. But the maximum precipitation gradually passes from south to north: in June it is in the steppe, in July - in the taiga, in August - in the tundra. Showers are observed during the passage of a cold front and during thermal convection.

In the middle and southern stripes of the plain, thunderstorms occur from May to August. So, for example, in the Baraba and Kulunda steppes, it is observed during the warm period from 15 to 20 days with thunderstorms. In Tobolsk, Tomsk, Tselinograd it was noted in July up to 7-8 days with thunderstorms. During thunderstorms, squalls, heavy showers, and hail are frequent.

The West Siberian Plain is crossed by three climatic zones: arctic, subarctic and temperate.

Rivers and lakes. The rivers of the West Siberian Plain belong to the basins of the Ob, Taz, Pur and Yenisei. The Ob basin covers an area of ​​about 3 million sq. km 2 and is one of the greatest river basins in the USSR.

Large rivers - the Ob, Irtysh, Ishim, Tobol - flow through several geographical zones, which determines the diversity of morphological and hydrological features of individual sections of the rivers and their valleys. All rivers of the West Siberian Plain are typically flat. They have small slopes: the average slope of the river. Ob - 0.000042, r. Irtysh from Omsk to the mouth - 0.000022.

The rivers flowing into the Ob and Irtysh have a flow velocity of 0.1-0.3 in the summer within the taiga region. m/s, and in the spring flood - 1.0 m/sec. All rivers flow in loose, mainly in Quaternary sediments, have a large sinuosity of the channel, wide valleys with well-defined floodplains and terraces.

The largest rivers - the Ob, Irtysh, Tobol - and many of their tributaries begin in the mountains. Therefore, they bring a large amount of detrital material to the West Siberian Plain and their hydrological regime depends in part on the melting of snow and ice in the mountains. The main course of the lowland rivers is directed to the north-north-west. The peculiarities of the ice regime are associated with this: on all rivers, ice formation begins in the lower reaches and

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gradually moves upstream. In the north, freeze-up lasts 219 days, and in the south - 162 days. The spring ice drift begins in the upper parts of the basins and gradually passes to the mouths of the rivers, as a result of which powerful ice jams form on large rivers and the water level in the rivers rises sharply. This creates strong floods and leads to vigorous development of lateral erosion in the valleys.

In the south, the rivers break up in April - May, in the north - from mid-May to mid-June. The duration of the spring ice drift is usually up to 25 days, but can reach up to 40 days. This is due to the following reasons: in the territory located in the lower reaches of the rivers, spring comes later; the ice on the rivers in the lower reaches reaches a large thickness, and therefore a large amount of heat is spent on its melting.

Rivers freeze from north to south in a much shorter period of time, about 10-15 days. The average duration of the navigation period in the upper reaches is 180-190 days (near Novosibirsk - 185 days, in the lower reaches - 155 days).

West Siberian rivers are fed mainly by snow, but, in addition, rain and soil. All rivers have a spring flood, and it can last quite a long time. The spring flood gradually turns into a summer flood, which depends on rains and groundwater.

River Ob. The Ob begins near the city of Biysk at the confluence of the Biya and Katun rivers. The length of the Ob, counting from the confluence of these rivers, is 3680 km, and if we take the source of the river as the beginning of the Ob. Katun, then its length will be 4345 km. The length of the Ob-Irtysh system from the sources of the Irtysh to the Kara Sea (including the Gulf of Ob) - 6370 km. According to the water content of the river The Ob occupies the third place among the rivers of the USSR, yielding the first two places to the Yenisei and Lena. Its average annual water consumption is 12,500 m 3 / sec.

The largest tributaries of the The Ob receives from the left (the Irtysh River with the Ishim and Tobol rivers), the right tributaries are much shorter, so the configuration of the river basin has an asymmetric shape: the right-bank part of the basin makes up 33% of the catchment area, and the left-bank part - 67%.

According to hydrographic and hydrological conditions and morphology of the valley of the river. The Ob is subdivided into three parts: The Upper Ob - from the confluence of the Biya and Katun rivers to the mouth of the river. Tom, Middle Ob - from the mouth of the river. Tom to the mouth of the river. Irtysh and Lower Ob - from the mouth of the river. Irtysh to the Gulf of Ob. The Upper Ob flows in the hilly foothills of the steppe Altai. The main tributaries of the Upper Ob are: on the right - the river. Chumysh and r. Inya, flowing through the Kuznetsk basin, on the left - the Charysh and Alei rivers, flowing from Altai.

The middle Ob flows through the marshy taiga plains, crossing the Vasyuganye-marshy plains. This area is characterized by excessive moisture, slight slopes of the surface and a dense network of slowly flowing rivers. In the middle reaches of the river The Ob receives many tributaries from both sides. The Lower Ob flows in a wide valley through the northern part of the taiga and forest-tundra.

Irtysh River - the largest tributary Obi. Its length is 4422 km, pool area - 1 595 680 km 2. The sources of the Irtysh are located at the edge of the glaciers and mountains of the Mongolian Altai.

The largest tributaries of the Irtysh on the right are the rivers Bukhtarma, Om, Tara, Demyanka, and on the left - Ishim, Tobol, Konda. The Irtysh flows through the steppe, forest-steppe and taiga zones. It receives large tributaries in the taiga zone, and the most stormy - from the Altai mountains; in the steppe - from

Semipalatinsk to Omsk, i.e. at a distance of over 1000 km, The Irtysh has almost no tributaries.

The narrowest section of the river valley. Irtysh - from the mouth of Bukhtarma to the city of Ust-Kamenogorsk. Here the river flows in a mountain gorge. Near the city of Semipalatinsk The Irtysh enters the West Siberian Plain and is already a typically flat river with a wide valley - up to 10-20 km width, and at the mouth - up to 30-35 km. The river bed is divided into branches by numerous sandy islands; the slopes of the channel are insignificant, the banks are composed of sandy-argillaceous deposits. Throughout the river The right side of the Irtysh is the highest bank.

Lakes. There are many lakes on the West Siberian Plain. They are found in all natural zones of the plain and are distributed both in river valleys and on watersheds. A large number of lakes is due to the flatness and poor drainage of the territory; activity of the ice cap and its melt waters; permafrost-failure phenomena; river activities; suffusion processes occurring in loose deposits of the southern part of the lowland; destruction of peatlands.

According to the origin of the basins, the lakes of the West Siberian Plain are divided into the following types: 1) lacustrine basins that have inherited the deepened sections of the hollows of the ancient runoff. Their formation is associated with the activity of water flows in the marginal zones of ancient glaciations and in the areas of flow of dammed waters of the Ob and Yenisei rivers during ice sheets. Lakes of this type are located in ancient runoff hollows. They are predominantly elongated or oval in shape and insignificant (0.4-0.8 m) depth: however, sometimes they reach a depth of 25 m; 2) lacustrine basins of depressions between ridges of outwash plains, most common in the south in the forest-steppe and steppe; 3) oxbow lakes of modern and ancient river valleys. The formation of such lakes is associated with abrupt changes in river channels in accumulative deposits. Their shapes and sizes are very diverse; 4) lake basins caused by thermokarst. They are common in the north of the plain in permafrost conditions and are found on all elements of the relief. Their sizes are varied, but not more than 2-3 km in diameter, depth - up to 10-15 m; 5) moraine lake basins formed in depressions of moraine deposits, especially in the marginal parts of ice sheets. An example of such lakes is the northern group of lakes on the Yenisei-Taz interfluve within the Siberian Uvals. In the south of the forest zone, ancient moraine lakes already have a transitional stage; 6) sory lakes formed in depressions in the mouth parts of tributaries in the lower reaches of the Ob and Irtysh rivers. During floods and spring floods, depressions are filled with water, forming huge reservoirs with an area of ​​​​several hundred square kilometers and a depth of 1-3 m, and in channels - 5-10 m. In summer, they gradually discharge water into the channels of the main river, and in the middle of summer, and sometimes by the end of it, flat areas covered with silt remain in place of the reservoirs. Lakes - sors - favorite places for feeding many species of fish, as they quickly heat up and are rich in food; 7) secondary lakes, the basins of which are formed due to the destruction of peat bogs. They are common in swamp forests on flat watersheds and river terraces. Their sizes reach from several square meters to several square kilometers at a depth of 1.5-2 m. There are no fish in them; 8) suffusion lake basins, common in the southern regions of the lowland. In loose deposits, from which silt particles are washed out under the action of groundwater, soil subsidence occurs. Depressions, funnels, saucers are formed on the surface. The emergence of the basins of many saline and bitter-salty lakes is apparently associated with suffusion processes.

Ground water. According to hydrogeological conditions, the West Siberian Plain is a huge artesian basin, which is called the West Siberian. The ground waters of Western Siberia are characterized by various conditions of occurrence, chemistry and regime. They lie at different depths in primary pre-Mesozoic, Meso-Cenozoic and Quaternary deposits. Aquifers are sands - marine and continental (alluvial and outwash), sandstones, loams, sandy loams, flasks, dense fractured rocks of a folded foundation.

The main areas of modern nutrition of the artesian basin are located in the southeast and south (Chulyshman, Irtysh and Tobolsk basins). The movement of water occurs from the southeast and south to north.

The groundwater of the foundation is concentrated in the cracks in the rocks. They are distributed in its peripheral part to a depth of approximately 200-300 m and at this depth they overflow into the loose strata of the Meso-Cenozoic. This is confirmed by the almost complete absence of water in deep wells in the central part of the basin.

In the Quaternary deposits, the waters are mostly free-flowing, except for those areas where they are concentrated in intermorainic fluvioglacial deposits and among the loamy strata of the Ob plateau.

In the Irtysh and Tobolsk artesian basins, the waters of the Quaternary deposits are fresh, saline, and brine in composition. In the rest of the West Siberian basin, the waters of the Quaternary deposits are fresh hydrocarbonate with a mineralization rarely exceeding 0.5g/l.

The rivers and lakes of the West Siberian Plain are widely used in the national economy. In flat wetlands, rivers are the most important means of communication. The Ob River and its major tributaries - the Irtysh, Tobol, Vasyugan, Parabel, Ket, Chulym, Tom, Charysh and others - are used for regular navigation. The total length of shipping routes within the West Siberian Plain is more than 20,000 km. The Ob River connects the Northern Sea Route with the railways of Siberia and Central Asia. The significant branching of the river systems of the West Siberian Plain makes it possible to use the tributaries of the Ob and Irtysh to transport goods from west to east and back over long distances. The most significant drawback of the Ob basin as a transport route is its isolation from neighboring river basins, despite the fact that the upper reaches of many tributaries of the river. The Obs come close to neighboring river basins; so, for example, the right tributaries of the Ob - the Ket and Vakh rivers - come close to the left tributaries of the river. Yenisei; left tributaries of the river. Ob and tributaries of the river. Tobol close to the river basin. Ural and to the river basin. Kama.

The rivers of the West Siberian Plain have huge energy resources: the Ob annually discharges 394 billion tons of electricity. m 3 waters in the Kara Sea. This corresponds approximately to the amount of water in 14 rivers such as the Don. On the Ob, above the city of Novosibirsk, the Novosibirsk hydroelectric power station was built. On the river Irtysh built a cascade of energy nodes. Rocky narrow valley Irtysh from the mouth of the river. Bukhtarma to the city of Ust-Kamenogorsk is the most favorable for the construction of hydroelectric power stations. Ust-Kamenogorsk HPP and Bukhtarma HPP were built.

Ichthyofauna of the river. Both are varied. In some parts of the river, various fish are of commercial importance. In the upper reaches, before the confluence of the river. Chulym, commercial fish are found: from sturgeons - sturgeon, sterlet; from salmon - nelma, cheese, muksun. Along the tributaries they catch Siberian roach (from cyprinids), crucian carp, pike, perch, burbot. In the middle reaches of the river Ob, where in winter the deadly phenomena are strongly developed, fish demanding oxygen leave. Fishes that live in rivers all the time are of commercial importance - roach (chebak), dace, ide, crucian carp, pike, perch. In summer, on the way to spawning or feeding, they come here: sturgeon, nelma, cheese, muksun. In the lower reaches of the river - up to the Gulf of Ob - there are: sturgeon, nelma, cheese, pizhyan, muksun, etc.

In the southern part of the West Siberian Plain there are many mineral lakes with large amounts of salt, soda, mirabilite and other chemical products.

Lakes are the most important source of water supply in many arid regions of the West Siberian Plain. But sharp fluctuations in the level of lakes, especially those with weak groundwater, affect their mineralization: in autumn, the volume of water in lakes usually decreases sharply, the water becomes bitter-salty and, therefore, cannot be used for drinking. In order to reduce evaporation and maintain a sufficient volume of water in lakes, they resort to embankment of lake basins, afforestation, snow retention in watersheds,

increasing catchment areas under favorable topographical conditions by connecting several isolated catchment basins.

Many lakes, especially Chany, Sartlan, Ubinskoye and others, are of fishing importance. In the lakes are found: perch, Siberian roach, pike, crucian carp, Balkhash carp, bream are bred. In the reed and sedge thickets of lakes from spring to autumn, a large number of waterfowl find refuge.

On the lakes of Baraba, large numbers of geese and ducks are harvested annually. In 1935, the muskrat was released into the lakes of the western part of Baraba. She acclimatized and settled widely.

geographic zones. On the vast West Siberian Plain, the latitudinal zonality of all components of nature that formed in the post-glacial period, namely, climate, soils, vegetation, waters, and wildlife, is exceptionally clearly manifested. Their combination, interconnection and interdependence create latitudinal geographical zones: tundra and forest-tundra, taiga, forest-steppe and steppe.

The natural zones of the West Siberian Plain but the area occupied are unequal (see Table 26).

The table shows that the dominant position is occupied by the forest zone, and the smallest area is occupied by the forest tundra.

The natural zones of the West Siberian Plain are part of the geographical zones stretching across the entire territory of the Soviet Union from west to east, and retain their common features. But due to the local West Siberian natural conditions (plains, widely developed clay-sand deposits with a horizontal occurrence, a climate with transitional features between the moderately continental Russian Plain and continental Siberia, severe swampiness, a special history of the development of the territory in pre-glacial and glacial times, etc.) zones of the West Siberian lowland have their own characteristics. So, for example, the subzone of mixed forests of the Russian Plain extends eastward only to the Urals. The oak forest-steppe of the Russian Plain does not cross the Urals. The West Siberian region is characterized by aspen-birch forest-steppe.

Tundra and forest tundra. From the shores of the Kara Sea and almost to the Arctic Circle, between the eastern slope of the Urals and the lower reaches of the river. Yenisei, tundra and forest-tundra stretch. They occupy all the northern peninsulas (Yamal, Tazovsky and Gydansky) and a narrow strip of the mainland part of the plain.

The southern border of the tundra near the Ob and Taz bays runs approximately at 67°N. sh.; R. It crosses the Yenisei to the north of the city of Dudinka. The forest-tundra stretches in a narrow strip: in the region of the Gulf of Ob, its southern border goes south of the Arctic Circle, and to the east of the Gulf of Ob, along the Arctic Circle; behind the river valley The Taza border runs north of the Arctic Circle.

The main rocks that make up the peninsulas and the islands adjacent to them - Bely, Sibiryakova, Oleniy and others - are Quaternary - glacial and marine. They lie on the uneven surface of the pre-Quaternary relief and consist of clay and sand with occasional boulders. The thickness of these deposits in depressions of the ancient relief reaches 70-80 m, and sometimes more.

A marine primary plain stretches along the coast with a width of 20-100 km. It is a series of sea terraces with different heights. There is an increase in the heights of the terraces to the south, which is apparently due to Quaternary uplifts. The surface of the terraces is flat, with scattered saucer-shaped lakes with a depth of 3-4 m. On the surface of sea terraces there are dunes 7-8 m, blowing pits. The formation of eolian forms is favored by: 1) the presence of loose sea sands not fixed by vegetation; 2) low moisture content of sands in spring and summer; 3) strong wind activity.

The inner parts of the peninsulas have a hilly moraine surface with numerous small lakes.

The formation of the modern relief of the peninsulas is greatly influenced by permafrost. The thickness of the active layer in many areas reaches only 0.5-0.3 m. Therefore, erosional activity, especially deep, is weakened. Erosive activity is hindered by prolonged drizzling rains and numerous lakes, which act as flow regulators throughout the warm season. Therefore, floods on the rivers do not occur. However, erosion activity is currently one of the main factors that transform the original relief of the moraine-hilly and marine plains: wide river valleys, many meanders, young ravines along ledges of terraces, valleys and lake basins. Slopes change as a result of deluvial washout, solifluction and landslides.

In areas of permafrost development, thermokarst phenomena are common, as a result of which sinkholes, funnels, saucers, and lakes are formed. The emergence of thermokarst forms is still taking place; this is evidenced by trunks and stumps immersed in lakes, flooded trees and shrubs, cracks in the ground. Spotted tundras form on even flat watersheds or on slightly sloping slopes. Spots devoid of vegetation reach in diameter from 1-2 to 30-50 m.

The harsh climate of the tundra is due to its northern position, the influence of the cold Kara Sea and the entire Arctic basin, as well as the lively cyclonic activity and cooling in the winter period of the neighboring territory - the region of the Asian anticyclone.

Winter in the West Siberian tundra is more severe than in Europe, but less frosty than east of the river. Yenisei. Average January temperatures are -20-30°. Winter types of weather prevail from mid-October to early May. The average monthly wind speed in the tundra is -7-9 m/s, maximum - 40 m/s, that at low temperatures, sometimes reaching -52 °, creates a great severity of the weather. The snow cover lies for about 9 months (from half of October to half of June). Under the influence of strong winds, snow is blown and therefore its thickness is uneven. The weather depends on the frequent passage of cyclones and on the intrusions of arctic air masses from the Kara Sea and polar continental air masses from Central Siberia.

In summer, Arctic air invades the entire territory, but the process of its transformation is still weakly expressed. Summer in the tundra is cool, with frosts and snowfalls. The average July temperature is about +4, +10°; maximum +20, +22° (Tombey), to the south it reaches +26, +30° (New Port); the temperature in summer drops to -3, -6°. In the forest-tundra, the average July temperatures are +12, +14°. The sum of temperatures above 10° on the southern border of the tundra is 700-750°.

Annual rainfall - from 230 mm in the northern part up to 300 mm in southern part. The maximum precipitation falls in summer, mainly in the form of long-term drizzling rains; showers with thunderstorms are rare. Due to the lack of heat, frequent precipitation, low evaporation and the presence of permafrost in places, the soil is heavily swamped, and the relative humidity of the air is very high. Evaporation on the coast - 150 mm, and on the southern border of the forest-tundra about 250 mm. The tundra and forest-tundra zone is characterized by an excessively humid climate.

Groundwater is shallow, which contributes to the waterlogging of the territory and the poor development of soil aeration. For most of the year, groundwater is frozen.

Soil formation occurs in the parent rocks of the Quaternary age - clayey-sandy deposits of glacial and marine origin. Soils are formed under conditions of low air and soil temperatures, low rainfall, insignificant drainage of the territory and lack of oxygen. All these conditions lead to the development of soils of the gley-bog type. However, the combination of local components of nature creates diversity in the formation of the soil cover. The most common are tundra gley and peat-bog soils, which form under conditions of strong moisture. On the sands, where there is no permafrost or it lies at great depths, there is no waterlogging and weakly podzolic soils develop. In the forest-tundra, the process of formation of podzolic soils is more pronounced: they are formed not only on sands, but also on loams. Therefore, the main types of forest-tundra soils are gley-podzolic.

When moving from north to south within the tundra, there is a change in climate, soil formation and vegetation cover.

BN Gorodkov identified the following subzones of the tundra: 1) the arctic tundra; 2) typical tundra; 3) southern tundra; 4) forest tundra.

The Arctic tundra occupies the northern parts of the Yamal and Gydan Peninsulas. The arctic tundra is dominated by patchy tundra. Its vegetation is very sparse and settles only in hollows and cracks surrounding bare patches of soil. Sphagnum mosses and shrubs are completely absent in the vegetation cover. The latter occasionally come from the south along the river valleys. The species composition is poor; the most typical species are: foxtail( Alopecurus alpinus), sedge ( carex rigida), moss ( Polytrichum strictum), sorrel ( Oxyria digyna), meadow grass ( Deschampsia arctica).

Typical tundra occupies the middle and southern parts of the Yamal and Gydan peninsulas and the northern part of the Tazovsky. The southern border of the tundra passes north of the Arctic Circle. The vegetation of a typical tundra is diverse. Mosses, lichens, forbs and shrubs are widespread: they are found not only along river valleys, but also on watersheds.

The vegetation of a typical tundra forms three tiers: the upper one is shrubby, consisting of birch( Betuladad), wild rosemary ( Ledumpalustre), shrub willow( Salix glauca, S. pulchra), blueberries ( Vaccinium uliginosum); medium - herbaceous - from sedges(Ca rex rigida), dropsy ( Empetrum nigrum), cranberries ( Oxycoccos microcarpa O. palustris), partridge grass (Dryas octopetala), bluegrass (Roa arctica), cotton grass ( Eriophorum vaginatum). Sedges predominate among other plants; the lower tier - lshpaynikovo-moss. It consists of lichens: alectoria( Alectoria), cetraria ( Cetraria), reindeer moss ( Cladonia rangiferina), mosses - hypnum and sphagnum( Sphagnum lenense).

Typical tundra is different in some areas: moss tundra is formed on moist clay soils. Lichen tundra develops on elevated loamy and sandy areas. In places of strong wind activity, there are small areas of patchy clay tundra. In spring and summer, moss tundras are good grazing grounds for deer, which eat cotton grass, shrub leaves, and various grasses. In the ravines, on the slopes of the southern exposure, tundra meadows develop, consisting of forbs. The meadows are used as summer pastures for deer.

Riverside thickets of willow bushes move north along the river valleys. Compared to other plant groups, shrubs develop under conditions of less waterlogging, thicker snow cover, and faster and deeper thawing of the active soil layer.

In the south of the typical tundra, shrubs begin to predominate in the vegetation cover. They form dense thickets of birch and willow up to 1.5-3 m not only along river valleys, but also on watersheds, among moss and lichen tundra. The wide development of shrub groups in the more southern parts of the tundra is explained by the weakened activity of the wind in winter, thicker snow cover and more precipitation.

The tundra is gradually replaced by the forest tundra. In the northern part of the forest-tundra, small areas of light forests and crooked forests appear, which increase in the south and pass into the taiga. In the forest-tundra, trees grow at some distance from each other; between them are areas of shrub, moss, lichen, and sometimes spotted tundra. The most favorable areas for woody vegetation are sandy areas, protected from wind activity and well warmed up. The forests consist of larch and spruce. Under the forest canopy, dwarf birch and shrub alder are often found. The ground cover consists of sphagnum mosses that form peat bogs with a hilly surface. In dry sandy places, where there is a fairly thick snow cover, the soil is covered with lichens, mainly reindeer moss. The main soil types are gley-podzolic.

The slopes of river valleys and terraces are covered in summer with juicy variegated meadows, consisting of ranunculus, wisps, valerian and berries. The meadows are an excellent pasture for deer in summer and autumn, and a habitat for many animals and birds.

For the tundra of the West Siberian Plain, the most typical of the animal world is the domestic reindeer. He gets his food all year round: reindeer moss, or reindeer moss, berries, mushrooms, leaves and grass. In the tundra, large reindeer-breeding state farms and collective farms have been created, provided with pastures and veterinary and zootechnical stations. The enemies of reindeer herds are wolves that live in the forest-tundra and tundra.

The polar fox, or polar fox, lives in the tundra and forest-tundra. It feeds on a variety of foods, but the main food is lemmings, or lemmings. In spring, it destroys bird nests, eating eggs and young chicks.

Lemming is a small tundra rodent. It feeds on the bark of willows and dwarf birches, plant foliage. It serves as food for many mammals and raptors. In the tundra of Western Siberia, there are two types of lemmings: Ob and hoofed.

Along the river valleys of the forest-tundra, in forests and thickets of bushes, forest animals are found: squirrel, hare, fox, wolverine, which penetrate far to the north - into the tundra.

There are especially many waterfowl in the tundra, of which geese, ducks, swans, and loons are the most typical of its landscape. The white partridge lives in the tundra all year round. The white owl in the tundra is a diurnal bird.

In winter, the tundra is poor in birds: few of them remain to live in difficult climatic conditions. Geese, ducks, swans, the red-throated goose fly south, nesting only in the tundra and forest-tundra, from the river. Ob to river Yenisei. The peregrine falcon is also a migratory bird, which feeds on waterfowl. Migratory birds spend no more than 2-4.5 months a year in the north.

For about 9 months the tundra is covered with snow. The thickness of the snow cover in some places reaches 90-100 cm. Arctic fox, ptarmigan, and lemmings burrow into loose, fine snow. Compacted snow contributes to the easy movement of tundra animals: for example, the arctic fox walks freely on the crust. In the white partridge, the claws lengthen and the fingers by autumn are covered with a dense cover of dense flexible feathers, forming a wide elastic surface. Because of this, the increased supporting surface of the paw allows it to run through the snow without sinking deep. With loose deep snow, the white partridge plunges into it up to the abdomen and can only wander around the bushes with great difficulty. Territories with little snow are the most favorable for deer, as they freely get reindeer moss from under the snow.

The most important economic problem in the development of the tundra is the development of vegetable growing. To do this, it is necessary to improve the soil by draining it, improving aeration, lowering the level of permafrost, protecting soil from freezing by accumulating snow in the fields, and introducing manure into the soil. Frost-resistant crops can grow in the tundra.

Forest zone. Most of the area of ​​the West Siberian Plain is covered with forests - taiga. The southern border of the forest zone approximately coincides with the parallel of 56°N. sh.

The relief of the taiga zone was created by the accumulative activity of continental glaciation, melted glacial and surface waters. The southern boundaries of the distribution of ice sheets passed within the forest zone. Therefore, to the north of them, the dominant type of relief is accumulative glacial plains, altered by the activity of melted glacial waters of the retreating maximum glacier and partially melted glacial waters of the last glaciations.

The area of ​​glacial plains is about 1/4 of the area of ​​the entire West Siberian Plain. The surface is composed of Quaternary deposits - glacial, water-glacial, alluvial, lacustrine. Their power reaches sometimes more than 100m.

The forest zone is included in the West Siberian continental climatic region. Continental temperate air dominates all year round.

The winter type of weather is predominantly anticyclonic and is associated with the Asian anticyclone, but passing cyclones create unstable weather. Winters are long, with strong winds, frequent snowstorms and rare thaws. Average January temperature: -15° in the southwest and -26° in the east and northeast. Frosts reach -60° in some areas. With the arrival of a cyclone, temperatures can change dramatically. Snow cover lasts about 150 days in the south of the zone and 200 days in the northeast. The height of the snow cover by the end of February reaches 20-30 cm in the south and 80 cm in the north-east. Snow cover lies from mid-October to mid-May.

In summer, air from the north flows into the forest zone of the West Siberian Plain. On the way to the south, it transforms and, therefore, in the northern regions it is still quite humid, while in the southern regions it warms up and moves further and further away from the saturation point. Summer throughout the territory is relatively short, but warm. Average July temperatures are +17.8° (Tobolsk), +20.4° (Tselinograd) and +19° (Novosibirsk).

The amount of precipitation - 400-500 mm, maximum - in the summer. Over the entire territory, at the same latitudes, more precipitation falls in the European part of the Soviet Union than in Western Siberia.

Long winters with low temperatures in the northern part of the plain contribute to the existence of permafrost, the southern border runs from west to east approximately within 61-62 ° N. sh. Under the channels, the roof of frozen soil is much lower than on the watersheds, and under the Ob and Yenisei rivers, it was not found at all.

Groundwater is fresh and occurs close to the surface (at a depth of 3-5 to 12-15 m). Extensive sphagnum swamps are developed on the watersheds. The rivers have slight slopes, flow slowly in wide, strongly meandering channels. This is associated with weak mineralization of river waters (50-150 mg/l) and poor aeration of stagnant waters. There are dams in the rivers. The essence of zamora phenomena is as follows: groundwater and swamp water, containing a small amount of oxygen and a lot of organic substances, enters the Ob and its tributaries. With the formation of ice on the rivers, the access of oxygen from the air stops, and the swamp water continues to flow into the rivers and absorb oxygen. This leads to oxygen deficiency and causes mass death of fish. The Zamora zone occupies an area of ​​about 1,060,000 km 2. To the north, the dead zone advances to the lower reaches of the river. Ob and extends even to the Gulf of Ob.

Soils. The formation of soils occurs in a flat, heavily swampy terrain, covered with taiga vegetation. The parent rocks are diverse: glacial, fluvioglacial, lacustrine and eluvial-deluvial consist of sandy, sandy-argillaceous and boulderless deposits, as well as loess-like loams. The forest zone of the plain is characterized by podzolic, podzolic-bog and peat-bog soils.

Vegetation. Within the forest zone, when moving from north to south, the following subzones are distinguished.

1. Subzone of pre-tundra larch woodlands. This subzone stretches in a narrow strip from the Cis-Urals to the river. Yenisei, expanding in the east.

The strip of light forest consists of Siberian larch( Larix sibirica) spruce ( Picea obovata) and cedar ( Pinus sibirica), especially in the southern part of the subzone, but spruce is more common in the west than in the east. The forests are sparse, treeless areas are occupied by small swamps and tundra formations.

2. The subzone of the northern taiga is characterized by an open forest stand and a wide distribution of flat-hummocky sphagnum bogs. Forests consist of larch with an admixture of spruce, birch, and cedar. In the northern part of the subzone, in some places they are clean, without impurities. Larch forests are widespread along the sands, and to the south, pine forests settle on the sands along river valleys and watersheds. The ground cover of forests is formed by lichens and mosses. Of the shrubs and herbs are typical: bearberry, shiksha, lingonberry, sedge (Carex globularis ) , horsetail ( Equisetum sylvaticum, E. pratense); the undergrowth consists of dwarf birch, rosemary and blueberry. These forests occupy large areas closer to the Yenisei and Ob rivers. Swamps dominate in the middle part of the northern taiga.

3. Middle taiga subzone. Dark coniferous forests are formed by spruce and cedar with an admixture of larch and fir( Abies sibirica). Larch is found throughout the zone, but in small areas. Birch is more widespread than in the northern taiga, which often grows together with aspen, forming birch-aspen forests. The dark coniferous taiga is characterized by great closeness and gloominess. Dark coniferous forests are unevenly distributed within the subzone. The most significant arrays are concentrated in the middle and eastern parts. To the west of the Ob and Irtysh rivers, pine forests with sphagnum bogs predominate. Spruce and cedar forests are found mainly in river valleys. They have a diverse grass cover and dense thickets of bushes from Siberian svidina (Cornus tatarica ) , bird cherry, viburnum, honeysuckle ( Lonicera altaica).

4. Southern taiga. For the southern taiga, the dominant species is fir; birch and aspen forests are widespread. In the west, in the southern taiga forests, there is a linden( Tilia sibirica) with a herbal companion - sleepweed( Aegopodium podagraria). The middle and southern taiga are distinguished under the name Urmano-marshy.

5. The subzone of deciduous forests is formed mainly by downy birch( Betula pubescens) and warty (AT. verrucosa) and aspen ( Populus tremula), alternating with grass and sphagnum bogs, with meadows and pine forests. Spruce and fir enter the subzone of deciduous forests. Birch and aspen forests are confined to soddy-podzolic soils, leached chernozems and solods.

Pine forests grow on the sands; they occupy the largest area in the river basin. Tobol.

The subzone of deciduous forests gradually turns into forest-steppe. In the west (west of the Ishim River), the forest-steppe is more forested than in the east. This is apparently due to the high salinity of the soils of its central and eastern parts.

The fauna of the West Siberian taiga has many common species with the European taiga. Everywhere in the taiga live: brown bear, lynx, wolverine, squirrel, ermine. Of the birds - capercaillie, black grouse. The distribution of many animal species is limited to the Ob and Yenisei valleys. For example, the roller, the European hedgehog do not penetrate east further than the river. Obi; beyond the Yenisei, the great snipe and the corncrake do not pass from the birds.

Riverside taiga and secondary aspen-birch forests are rich in animals. Typical inhabitants of these forests are elk, white hare, ermine, Siberian weasel. Previously, the beaver was found in large numbers in Western Siberia, but at present it has been preserved only along the left tributaries of the Ob. A beaver reserve was organized here along the rivers Konda and Malaya Sosva. Muskrat (musk rat) is successfully bred in reservoirs. American mink was released in many places in the West Siberian taiga.

Birds nest in the taiga. Cedar forests are a favorite place for nutcrackers; in the larch forests, the Siberian crossbill is more common; in the spruce forests, the three-toed woodpecker taps. There are few songbirds in the taiga, so it is often said that the taiga is silent. The most diverse bird kingdom is on birch-aspen burnt areas and on the banks of rivers; here you can meet waxwing, finches, long-tailed bullfinch, rubythroat nightingale. On reservoirs - geese, ducks, sandpipers; in the moss swamps far to the south, almost to the forest-steppe, the white partridge comes. Some birds arrive in the West Siberian taiga from the southeast. Many of them winter in China, Indochina, on the Sunda Islands. Long-tailed bullfinch, rubythroat nightingale, etc. fly there for the winter.

Commercial value are: squirrel, fox, ermine, weasels. Of the birds - hazel grouse, black grouse, capercaillie and white partridge.

Forest-steppe and steppe The West Siberian Plain was formed in special physical and geographical conditions, namely: on a flat, poorly drained terrain, on saline parent rocks, at a considerable distance from the oceans, with a more continental climate. Therefore, their appearance differs sharply from the forest-steppe and steppe of the Russian Plain.

The West Siberian forest-steppe stretches in a narrow strip from the Urals to the foothills of the Salair Ridge and Altai.

This is the southern part of the Tertiary marine plain, covered with loose Quaternary deposits, ancient alluvial and fluvioglacial.

sands, deluvial loess-like loams, loess and modern lacustrine and alluvial sands and clays.

Bedrocks - tertiary clays, sands, loams - are exposed by river valleys and come out in natural outcrops in bedrock banks or at the base of terraces in the western, southern and southeastern parts of the steppe zone, where tertiary rocks are elevated and form plateaus or inclined plains.

The modern relief of the forest-steppe and steppe was greatly influenced by ancient streams, which formed wide runoff troughs crossing the Priobskoye plateau, the Kulunda, Baraba lowlands and other territories. Ancient hollows are directed from the northeast to the southwest. The bottoms of the hollows are flat, composed of loose deposits. The interfluves between the hollows of the runoff are elongated in the same direction as the hollows, and are called "manes". Modern rivers flow through the hollows, which flow either into the Ob and Irtysh or into lakes, or are lost in the steppe. All these landforms are clearly visible from an airplane, especially in early spring, when snow spots still remain in them, and the watershed areas have already been freed from snow. One of the features of the steppe and forest-steppe zones of Western Siberia is the abundance of lake basins. They are common on flat watersheds and in river valleys. The largest of them are the lakes of the Baraba steppe, where the largest shallow lake is located. Chany and Ubinskoye lake. Of the lakes of the Kulunda steppe, the largest is Kulunda. The lakes of the Ishim steppe are mostly shallow. The large lakes are Selettengiz. There are many small lakes on the Ishim-Irtysh sloping plain and the Ishim Upland.

Thousands of lakes occupy depressions in ancient hollows; they are the remains of former river channels. The shores of such lakes are low, often swampy or overgrown with pine forests. The lakes are fed by melt and rain water formed as a result of surface runoff. For many reservoirs, especially large ones, ground feeding is also essential.

Lakes periodically change their level, and, consequently, their outlines and their water supply: they dry up, then refill with water 1 . The change in the level of lakes is associated with fluctuations in climatic conditions: with the ratio of precipitation and evaporation. Some influence on the change in the level of lakes is also exerted by human activities during the construction of dams, laying ditches, burning birch chops, and mowing reed beds along the banks. So, for example, in the Baraba, Kulunda and Ishim steppes, after fires, new lakes arose up to 1.5-2 m. After mowing the coastal thickets of reeds and reeds, some of the freshwater lakes in the Kulunda steppe turned into saline ones, since in winter snowdrifts stopped accumulating on them, which led to a sharp reduction in one of their most important sources of nutrition.

Over the past 250 years (with XVII to the middle XXc.) seven complete cycles of fluctuations in the levels of steppe lakes have been established, usually lasting from 20 to 47 years. Based on the analysis of atmospheric precipitation and temperature regime, cycles of high and low activity of precipitation, warm and cold periods were revealed.

Thus, the dependence of fluctuations in the level of lakes on fluctuations in atmospheric precipitation and air temperature is outlined.

It is assumed that fluctuations in the levels of individual lakes are associated with neotectonic movements. Fluctuations in the levels of the lakes of the Chany group were repeatedly recorded.

The steppe and forest-steppe are dominated by lakes containing brackish water (Chany, Ubinskoye, and others). Lakes are divided according to their chemical composition into three types: hydrocarbonate (soda), chloride (actually salty) and sulfate (bitter-salty). In terms of reserves of salt, soda and mirabilite, the lakes of Western Siberia occupy one of the first places in the USSR. Kulunda lakes are especially rich in salts.

The climate of the forest-steppe and steppe of the West Siberian Plain differs from the climate of the forest-steppe and steppe of the Russian Plain by greater continentality, manifested in an increase in the annual amplitude of air temperature and in a decrease in the amount of precipitation and the number of days with precipitation.

Winter is long and cold: the average January temperature in the forest-steppe drops to -17, -20°, sometimes frosts reach -50°; in the steppes, the average January temperatures are -15, -16°, frosts also reach -45, -50°

The least amount of precipitation falls in winter. The first half of winter is characterized by snowfalls and strong winds, the speed of which in the open steppes reaches 15 m/sec. The second half of winter is dry, with weakened wind activity. The snow cover has a small (40-30 cm) power and is unevenly distributed over the surface of the forest-steppe and steppe.

In the spring, insolation and air temperature increase rapidly. The snow cover melts in April. Snow melts very quickly, in the steppe - sometimes in one week.

The average air temperature in the steppe in May reaches + 15°, and the highest - up to + 35°. However, in the first half of May there are severe frosts and snow storms. After the snow melts, the temperature rises very quickly: already in the first decade of May, the average daily temperature exceeds +10°C.

In the formation of dry spring weather, dry winds are of great importance, which are most frequent in May. During dry winds, the temperature

air reaches +30°, relative humidity below 15%. Dry winds are formed during the southern winds that occur on the western outskirts of the Siberian anticyclones.

Summer in the forest-steppe and steppe is hot and dry with frequent winds and dry weather types. In the forest-steppe, the average temperature is about +19°, in the steppe it rises to 22-24°. Relative humidity reaches 45-55% in the steppe, and up to 65-70% in the forest-steppe.

Droughts and dry winds are more common in the first half of summer. During summer dry winds, the air temperature can rise to +35, +40°, and the relative humidity reaches about 20%. Droughts and dry winds are caused by the penetration and intensive heating of the Arctic air masses and the intrusion of hot and dry air from Central Asia. Every year, especially in dry years, dust storms occur in the steppes from April to October. Most of them are in May and early June. More than half of the annual precipitation falls during the summer.

The first half of autumn is often warm. In September the air temperature can reach +30°; however, there are also frosts. A rapid drop in temperature is observed from October to November. Precipitation intensifies in October. Moisture accumulates in the soil in autumn, as evaporation is negligible at this time. In the northern part of the steppe, snow cover appears at the end of October. From November, persistent frosts set in.

The history of the formation of the forest-steppe and steppe of the West Siberian Plain in the Tertiary and Quaternary periods differed sharply from the history of the formation of the steppe and forest-steppe of the Russian Plain. Therefore, the modern appearance of the forest-steppe and steppe of Western Siberia has its own characteristics, which are most clearly manifested in the relief, soils and vegetation. The modern continental climate contributes to the development of the more arid steppes of the West Siberian Plain compared to the East European Plain and enhances their differences.

The forest-steppe and steppe of the West Siberian Plain is dominated by primary flat, poorly drained plains covered with extensive swamps, numerous fresh and salt lakes, saucers, wide hollows and manes.

The ravine-gully network is less developed than on the Russian Plain. However, the manifestation of ravine activity is observed in all natural zones of the West Siberian Plain, and especially on the sloping plains and plateaus adjacent to the Urals and Altai, and along the valleys of the Ob and Irtysh rivers. In the steppes, nivation ravines are widely developed, the formation of which is due to the accumulation of snow under the action of strong winds near various natural barriers, especially in gullies and ravines. Soil-forming processes occur in a geologically young, poorly drained area with saline soil, under conditions of insufficient moisture. The zonal soils of the forest-steppe of Western Siberia are meadow-chernozem, leached and podzolized chernozems.

Solonchaks, solonetzes and solods are widespread; their formation is associated with shallow groundwater, soil salinity, and increased evaporation. They are confined to depressions. Due to the increase in humidity, the process of soil leaching increased, which led to the destruction of solonetzes and the emergence of solods.

In the steppe zone, southern and ordinary chernozems are developed, which gradually turn into dark chestnut soils with a humus horizon of up to 50 m and with a humus content in the range of 3-4%. Dark chestnut soils have weak signs of alkalinity, an insignificant depth of effervescence and a large amount of gypsum at a depth of 1m.

The forest-steppe of the West Siberian Plain is called the birch forest-steppe. From the northern part of the forest-steppe, the forest cover of the territory is about 45-60%. Isolated birch forests are called birch groves. The pegs consist of downy birch with an admixture of aspen, warty birch and willow in the undergrowth. The grass cover in the pegs is formed by steppe and forest species. Bone is typical of the forest( Rubus saxatilis), bought ( Polygonatum officinale) ; from shrubs - currant ( Ribes nigrum). Of the conifers in the forest-steppe, pine is common. Pine forests occupy sandy and sandy loamy areas and go along the floodplain terraces of the valleys to the south to the steppe zone. Under the canopy of pines, taiga plant groups are moving south - satellites of pines: sphagnum bogs, on which wintergreens, lingonberries, blueberries, cranberries, sundews, cotton grass, sedges and orchids grow. On the most elevated, dry places, white moss forests with a ground cover of reindeer lichen (moss moss) are developed. The soil cover of pine forests is very diverse and consists of podzols, dark-colored solod peaty soils and solonchaks. But at the same time, steppe species (fescue and steppe timothy grass) are common in the grass cover of southern pine forests.

The steppe areas have a dense herbaceous cover, consisting of typical meadow rhizomatous grasses: reed grass, meadow bluegrass, steppe timothy grass. From legumes are often found: clover and peas, and from Compositae - meadowsweet( Filipendula hexapetala), solonchak forms appear on solonchaks.

When moving south, the grass cover of the steppes thins out, the species composition changes - steppe species begin to predominate, while meadow and forest species are noticeably reduced. Sod xerophytes predominate among cereals: fescue( Festuca sulcata) and thin-legged ( Koeleria gracilis), feather grasses appear( Stipa rubens, St. capillata). Of the herbs, alfalfa is the most typical( Medicago falcata) and sainfoin ( Onobrychis arenaria). Salt marsh plants begin to meet more often: licorice, saltwort, large plantain, astragalus. There are fewer birch groves, and the forest cover of the territory is only 20-45%.

In the West Siberian forest-steppe, as already noted, swampy areas, which are called borrowings, are widespread. Zaimishchas are covered with marsh vegetation: sedge, reeds, reeds, cattails. They occupy low interfluve spaces and are the final stage of overgrowing water bodies. Loans are especially plentiful in the Baraba steppe. In addition, in the West Siberian forest-steppe, moss-sphagnum bogs are common, overgrown with a rare, oppressed pine. They are called ryams. Pine forests, occupants and ryams in the conditions of the modern dry climate should be considered intrazonal plant groups, possibly formed during the Ice Age.

The steppes occupy the extreme south of the West Siberian Plain. Within the steppe zone of Western Siberia, two subzones are distinguished: the northern - feather grass-forb chernozem steppe and the southern - feather grass-fescue chestnut steppe. The composition of the northern steppes is dominated by xerophytic narrow-leaved grasses: reddish feather grass( Stipa rubens), hairy, fescue, thin-legged, desert sheep ( Auenastrum desertorum), timothy. Forbs are less abundant than in the steppes of the forest-steppe, and consist of yellow alfalfa, bedstraw, speedwell, sleep-grass, cinquefoil, wormwood.

In terms of species composition and aspect, the West Siberian steppes differ from the colorful European steppes of this subzone. In the Siberian steppes there are no sage, raven, blush, clovers( Trifolium montanum T. alpestre), but xerophytic forbs predominate.

Sod grasses dominate in the southern steppes of the West Siberian Plain: fescue, thin-legged and hairy feather grass. Abundant rhizomatous steppe sedge( Carex sypina). Of the forbs, xerophytic species predominate, for example: wormwood ( Artemisia glauca, Alatifolia), onion ( Allium lineare) , Adonis ( Adonis wolgensis), gerbils ( Arenaria graminifolia); many Siberian forms that do not enter the European steppe: iris ( Iris scariosa), goniolimon ( Goniolimon speciogum) and etc.

The grass cover is sparse, and the turfiness of the steppes reaches 60-40%. On the shores of lakes, on salt licks, solonetsous species grow, for example, sea wormwood. In depressions with close occurrence of groundwater and along the shores of salt lakes, solonchaks with typical halophyte vegetation predominate: soleros, solonchak barley, licorice.

In the steppes along the river valleys, hollows of the ancient runoff, ravines there are thickets of willow, birch, along the sands - patches of pine forests (green mosses, lingonberries and white mosses with a large number of steppe species). So, for example, in the valley of the river. On the sandy right-bank terrace of the Irtysh, extensive pine forests stretch from the city of Semipalatinsk to the city of Pavlodar.

The floodplains of large rivers are covered with meadow vegetation, which forms a dense succulent herbage of wheatgrass, steppe alfalfa, water-loving; closer to the water, marsh associations of reeds and sedges dominate. Wet floodplain meadows are an example of a sharp contrast with dry feather-grass-fescue steppes, which quickly burn out in summer.

The northern and southern steppes are used as pastures and hayfields. Most of their territory is plowed up.

The most significant natural difficulties for agriculture in the steppe zone of the West Siberian Plain are the dryness of its climate and the penetration of dry winds.

Forest plantations and belt pine forests contribute to an increase in the yield of grain crops, since the humidity of the air and soil near them increases, and the amount of precipitation increases compared to the treeless steppe. In ribbon pine forests and forest belts, in addition to the main species, pine, pedunculate oak, small-leaved linden, Amur larch, Amur velvet, and in the undergrowth - Amur acacia and bird cherry Maak are planted.

The fauna of the forest-steppe is more diverse than the fauna of the steppe, since the latter is characterized by the uniformity of ecological conditions over vast areas. The fauna of the forest-steppe includes forest and steppe species. Along the pegs and ribbon forests, the northern (taiga) elements penetrate to the south even into the feather grass-fescue steppes, and along the meadow-steppe areas, the steppe elements enter the northern part of the forest-steppe; so, for example, in the Kulunda pine forests live along with steppe species - garden oatmeal, field pipit, upland jerboa - taiga animal species: squirrel, flying squirrel, capercaillie.

In the forest-steppe and steppe there are animals that live in the tundra. They are relics of the Ice Age. The white partridge is found even in the steppes of Kazakhstan up to 50.5 ° N. sh., its nesting sites are known on the lake. Vats. It never penetrates as far to the south as in the West Siberian steppes. On the lakes of the forest-steppe and the steppe, there is a gull-gull, typical of the tundra zone of Taimyr.

The fauna of the forest-steppe and steppe has many features in common in terms of the composition of the fauna and its origin with the fauna of the European steppe and forest-steppe, but the geographical features of the West Siberian Plain predetermined its difference from neighboring territories.

Of the mammals in the forest-steppe and steppe, there are many rodents: voles, steppe pied, earth hare - the largest of the jerboas ( Allactaga gaculus); Djungarian hamster, red-cheeked ground squirrel are often found ( Citellus erythrogenus). The steppe is characterized by a small, or gray, ground squirrel, marmot (baybak).

Of the carnivores in the steppe and forest-steppe live: wolf, fox, steppe polecat. A small fox, a corsac fox, comes into the steppe from the south. In the forests of the forest-steppe, typical taiga species are found: Siberian weasel, weasel, ermine.

AT XIV- XIXcenturies in the steppes of the West Siberian Plain there were such animals that are currently distributed only in the forest zone. For example, in the valleys of the Tobol, Ishim and Irtysh rivers, south of the city of Petropavlovsk and Lake. Chany, there was a beaver, and a bear was found near the city of Kustanai and between the cities of Petropavlovsk and Tselinograd.

Among the birds of the forest-steppe there are many European forms (common bunting, oriole, chaffinch). In the steppe areas, the common and Siberian larks are numerous, and the little bustard and bustard are occasionally found. In the southern steppes there are more of them: there are four species of larks (the small, or gray, lark penetrates from the desert into the steppe). Demoiselle crane and steppe eagle are found. Black grouse, gray and white partridge are the subject of winter fishing.

The fauna of insects is abundant, consisting of small locust grasshoppers, which sometimes damage crops, and “gnats” - mosquitoes, midges, horseflies.

There are four physical-geographic regions on the West Siberian Plain. Their occurrence is due to the history of the development of the territory in the Quaternary period and modern geographical zonality. Physical-geographical regions are located in the following order when moving from north to south: 1. Marine and moraine plains of the tundra and forest-tundra zones. 2. Moraine and outwash plains of the forest zone. 3. Alluvial-lacustrine and alluvial plains of the forest and forest-steppe zones. 4. The area of ​​lacustrine-alluvial and erosion plains with a cover of loess-like rocks of the forest-steppe and steppe zones. Each of these areas has internal morphological, climatic and soil-vegetative differences, and therefore is divided into physiographic regions.

- Source-

Davydova, M.I. Physical geography of the USSR / M.I. Davydova [and d.b.]. - M .: Education, 1966. - 847 p.

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The West Siberian Lowland is a single physical-geographical region consisting of two flat bowl-shaped depressions, between which there are uplands elongated in the latitudinal direction (up to 175-200 m), orographically combined into Siberian ridges.

Almost from all sides the lowland is outlined by natural boundaries. In the west it is distinctly delimited by the eastern slopes of the Ural Mountains, in the north by the Kara Sea, in the east by the valley of the Yenisei River and the cliffs of the Central Siberian Plateau. Only in the south is the natural boundary less pronounced. Gradually rising, the plain passes here into the adjoining uplands of the Turgai plateau and the Kazakh hills.

The West Siberian lowland occupies about 2.25 million km 2 and has a length of 2500 km from north to south, and 1500 km from east to west (in the widest southern part). The exceptionally flat relief of this territory is explained by the alignment of the complex-folded basement of the West Siberian Platform with a thick cover of Meso-Cenozoic deposits. During the Holocene period, the territory experienced repeated subsidence and was an area of ​​accumulation of loose alluvial, lacustrine, and in the north - glacial and marine deposits, the thickness of which in the northern and central regions reaches 200-250 m. However, in the south, the thickness of Quaternary deposits drops to 5-10 m and in the modern relief, signs of the influence of neotectonic movements are clearly manifested.

The peculiarity of the paleogeographic situation lies in the strong watering of the territory inherited from the Holocene and the presence at present of a huge number of residual water bodies.

Large modern landforms of Western Siberia are morphostructures created by the latest movements of the earth's crust. Positive morphostructures: uplands, plateaus, ridges - have a more dissected relief and better drainage. Dominant for the relief of the territory are negative morphostructures - plains covered with a thickness of loose layered deposits, often gleyed to a great depth. These properties worsen the water permeability of the strata and slow down the ground runoff.

The flatness of the territory determined the special nature of the hydrographic network: low water flow rates and significant tortuosity of the channels. The rivers of Western Siberia have a mixed supply - snow, rain, ground, with a predominance of the first. All rivers are characterized by a long spring flood, often turning into summer, which is explained by the different opening times of the rivers in different parts of the watersheds. Flood waters, spilling over many kilometers, are an important factor in the extremely high watering of watersheds, and rivers practically do not play their draining role during this period.

Thus, the combination of physical and geographical factors that favorably influence the bog-forming process determined the intensity of the formation and accumulation of huge peat reserves and the widespread distribution of peat deposits throughout the entire territory of the West Siberian Plain.

The vegetation cover of peat deposits in the West Siberian Lowland has not been studied in sufficient detail. The tree layer of forested peatlands here is much richer in species composition due to the species characteristic of the taiga forests of Siberia, such as cedar, fir, and larch. Usually, together with birch, spruce, and pine, they make up the forest stand of swamps in various combinations and quantities. Almost pure plantations of birch on peatlands are quite frequent and, under appropriate conditions, are found in all peat-bog regions of the West Siberian Lowland. On the lowland peatlands of the floodplains, pure willow thickets are noted.

In the shrub layer of the vegetation cover of the West Siberian swamps, such a representative of the Siberian flora as Salix sibirica is found, but the European species Calluna vulgaris is not reflected in it. Representatives of the Siberian flora were also noted in the grass layer: Carex wiluica, Cacalia hastata, Ligularia sibirica. Carex globularis, found in the European part of the Union as part of the vegetation of swampy spruce forests, has expanded its habitat in Western Siberia and is found in large numbers on typical high-moor peat bogs. sp. rubellum and Sph. cuspi datum are typical inhabitants of raised peat bogs in the northwestern region of the European part of the Union; they are rarely found in the moss cover of peat bogs in the West Siberian Lowland. But in much greater numbers and in more southern latitudes, Sph. lindbergii and Sph. congstroemii, which are typical for the peatlands of the Arkhangelsk region and are rare in the peatlands of the middle zone. Sometimes Cladonia and Cetraria form continuous patches in the ridge-lake areas of the watershed peatlands of the Vasyugan region, and up to 12 species of Cladonia are found in this regenerative complex.

Of the plant phytocenoses of the West Siberian Lowland, it is necessary to note the grass-sedge phytocenosis, which covers large areas in the marginal areas of the lands (under conditions of some soil salinity). It includes reed grass (Scolochloa festucacea), reed grass (Calamagrostis neglecta), Carex omskiana, C. appropinquata and C. orthostachys. Peat bogs are characterized in the tree layer by birch (up to 15–20 m high) and conifers: spruce, cedar, pine, larch; in the undergrowth, along with willows (Salix sibirica, S. pentandra), blackcurrant, mountain ash, bird cherry; in the shrub layer - marsh myrtle, cranberries, blueberries, cloudberries. The herbage is rich in species and flourishes; C. caespitosa dominates in it, C. globularis, C. disperma are found among other sedges, and taiga plants (Equisetum silvaticum, Casalia hastata, Pyrola rolundifolia) grow in forbs along with marsh plants. Elements of the taiga flora are also noted in the moss cover: on hummocks of Sph. warnstorfii - Pleuroziumschreberi and Hylocomium splendens, in interhummock depressions - Thuidium recognitum, Helodium blandowii, on the slopes of hummocks - Climacium dendroides. Iron efflorescences can often be observed in the depressions between the bumps in the sogres.

Most often, the edge areas of low-lying marshy swamps of the floodplain terraces along the channels of the Ob, Irtysh, Chulym, Keti, and Tyma rivers are covered with sorams. From the outside, they gradually turn into swampy forests, towards the center of the peat bog - into a forest complex phytocenosis.

In the West Siberian Plain, borrowings predominate in the Ishim peat-bog region on the interfluve of the Ishim and Tobol in their middle reaches. Here they adjoin lakes or surround them with a continuous ring. Huge areas are sometimes occupied by borrowings in lowlands, no longer connected with lakes, but bearing the features of former channels between lakes.

Zaimishchno-ryam peatlands are often found in the eastern part of the South Baraba peat-bog region, where they are confined to lakes or flat depressions in which surface waters stagnate for a long time. Among the loans scattered raised raised peat bogs, occupying a small area compared to the loans. These are well-known "ryams". During the growing season, a variable water-mineral regime is created in the lands: in spring and in the first half of summer they are flooded with fresh deluvial meltwater, and often hollow rivers; in the second half of the growing season, the borrowings on a larger peripheral area dry up, and here favorable conditions arise for capillary rise to the surface of saline soil and groundwater, and efflorescences of salts (Ca, Cl and SO 3) are usually observed on the surface.

The area of ​​the loan can be subdivided into: a zone of constant moistening with relatively fresh waters (the central part of the loan, shores of lakes and river channels) and a zone of variable moistening, where both the degree of watering and the degree of salinity of feed waters are variable (peripheral parts of the loans).

The central parts of the lands are covered with reed phytocenosis, in which the main background plants are reed, reed (Scolochloa festucacea), reed grass, sedges (C. caespitosa and C. wiluica). As an admixture, the phytocenosis includes Carex omskiana, C. buxbaumii, watch, bedstraw (Galium uliginosum). Among the components of the reed phytocenosis, reed, reed grass, Carex caespitosa and C. buxbaumii are salt-tolerant plants.

In the zone of borrowings where constant moisture begins to give way to variable moisture, under conditions of some salinity of the substrate, gradual thinning of reed beds and the introduction of sedges (C. diandra, C. pseudocyperus), cattail and reed grass are observed. The sedge-reed phytocenosis is characterized by scattered scattered birch (B. pubescens) and willow (S. cinerea) bushes.

Along the periphery of the borrowings in the zone of variable moistening, reedweed (Scolochloa, festucacea), which under the conditions of Baraba is an indicator of mixed chloride-sulfate salinization, displaces reed grass from the vegetation cover, and here a grass-sedge phytocenosis arises mainly from reedweed, Carex omskiana, C. appropinquata and C. orthostachys with a small contribution of the same reed.

The formation and development of ryams (oligotrophic pine-shrub-sphagnum islands) occurs in isolation from saline soils in both horizontal and vertical directions. Isolation in the horizontal direction is the deposit of loans; isolation in the vertical direction is a layer of reed peat with an average degree of decomposition of 22-23%, underlying the upper ryam deposit. The thickness of the reed peat is 0.5-1.5 m, the thickness of the upper fallow is 0.5-1 m. The stumpiness of the sphagnum deposit is low and decreases from the upper layers to the lower ones.

The surface of the ryam is sharply convex with asymmetrical slopes. Under the pine tree layer, there is a shrub layer and a moss cover of Sph. fuscum with admixture of Sph. angustifolium and Sph. magellanicum.

The largest ryams up to 1000-1500 ha (Big Ubinsky and Nuskovsky) are found in the northern and middle parts of the forest-steppe zone. Usually the area of ​​ryams is 100-400 ha, sometimes 4-5 ha (small ryams of the Chulym region).

The peat deposits of Western Siberia are extremely diverse in terms of the conditions of formation and development, the qualitative and quantitative indicators of the deposit, vegetation cover, the nature of distribution and other factors, in the change of which there is a fairly clear pattern closely related to natural latitudinal zonality. According to this principle, 15 peat-bog areas have been identified on the territory of Western Siberia.

The extreme north of the West Siberian Lowland occupies area of ​​arctic mineral sedge bogs. It geographically corresponds to the West Siberian subzone of the Arctic tundra. The total swampiness of this territory is almost 50%, which is a consequence of the water-resistant frozen layer located close to the surface, the excess of precipitation over evaporation and the flatness of the country. The thickness of the peat layer does not exceed a few centimeters. Deeply deposited peatlands should be classified as relics of the Holocene climatic optimum. Polygonal and even moss-sedge bogs are common here.

Noteworthy is the wide distribution of eutrophic moss-sedge bogs with a flat surface (up to 20-25% of the total area). It is dominated by Carex stans or Eriophorum angustifolium with a mossy carpet of Calliergon sarmentosum and Drepanocladus revolvens.

In the river valleys among the sedge marshes there are mounds covered with Sph. warnstorfii, Sph. lenense, Dicranum elongatum and lichens. Of the flowering plants, thickets of Betula nana and Rubus chamaemorus are abundant.

Along the shores of the bays and the Kara Sea, there are maritime marshes, which are flooded with sea water during surge winds. These are largely brackish bogs with grasses (Dupontia fisonera), sedges (Carex rariflora, etc.) and Stellaria humifusa.

The moss tundra is especially characterized by the abundance of Eriophorum angustifolium on the moss cover of Aulacomnium turgidium, Camptothecium trichoides, Aulacomnium proliferum, Dicranum elongatum, Ptilium ciliare. Sometimes sedges (Carex stans, Carex rotundata) with a similar composition of moss cover and the participation of sphagnum mosses predominate in the swampy tundra.

South is located area of ​​flat bogs. This zone geographically corresponds to the tundra. The swampiness of the zone is high (about 50%).

Flat-hilly peatlands represent a mosaic complex of hillocks and hollows. The height of the hillocks ranges from 30 to 50 cm, rarely reaches 70 cm. The area of ​​the hillocks is up to several tens, less often hundreds of square meters. The shape of the mounds is lobed, round, oval, elongated or ridge-like, the tops of the mounds are occupied by lichens, mainly Cladonia milis and Cladonia rangiferina. Less common are Cetraria nivalis, C. cucullata, Cladonia amanrocraea. The slopes of the mounds are covered with green mosses. Abundant are Aulacomnium turgidium, Polytrichum strictum, Dicranum elongatum. Of the flowering plants, strongly oppressed Ledum palustre and Rubus chamaemorus grow in clusters. Between them are fragments of dicrane-lichen associations. Hollows are heavily watered with a continuous carpet of sphagnum mosses from Sph. lindbergii, Sph. balticum, Sph. subsecundum, Sph. Jensenii. Less commonly, Drepanocladus vernicosus, Drepanocladus fluitans are found in the hollows; Along with marshes, swampy areas are widespread, which are swampy shrub tundra with Betula papa and willows, sometimes with Ledum palustre, swampy moss tundra with Betula papa and Ledum palustre, tussock tundra with Eriophorum vaginatum.

Area of ​​large-hilly swamps occupies the northern part of the forest zone and the southern forest-tundra. The swampiness of the zone is high. The hillocks are found singly, but more often they are located in groups or ridges 1-2 km long, up to 200 m wide. Single hillocks have a height of 2-2.5 m, soil hillocks 3-5 m, hillocks of the ridges reach a height of 8-10 m. Diameter bases of mounds 30-80 m, steep slopes (10-20°). Elongated depressions between hillocks are occupied by cottongrass-sphagnum and sedge-sphagnum oligotrophic or eutrophic hollows, sometimes with small lakes in the center. The surface of the largest mounds is broken by cracks up to 0.2-0.3 m deep. At the base of the mounds, sphagnum mosses grow and a layer of shrubs is developed, mainly Betula papa. Higher up the slope, lichens predominate. They are also characteristic of flat tops, which are often subjected to wind erosion.

Hilly peatlands are composed of peat up to 0.6 m thick on top, under which lies a highly ice-saturated mineral core, consisting of ice and loamy, silt-loamy, less often sandy material. The mineral core, in addition to ice-cement and its individual crystals, contains numerous ice interlayers, the thickness of which reaches several tens of centimeters and usually increases downwards, the number of interlayers also decreases downwards.

North Ob peat-bog region It is a poorly drained lacustrine-alluvial plain composed of medium- and fine-grained sands with a distinct horizontal layering.

The area is characterized by extremely high waterlogging. Peat deposits occupy more than 80% of the territory; form complex systems, covering flat interfluves and high river terraces. Raised convex heavily watered sphagnum peatlands dominate with ridge-lake complexes on flat tops and ridge-lake-hollow complexes on their slopes.

Areas with well-drained peatlands are insignificant and confined to the territory with the highest surface elevations. Fuscum and pine-sphagnum phytocenoses with a large number of various lichens are common here.

Lowland peat deposits are located mainly on the first floodplain terraces of large rivers.

The deposits of raised peatlands are shallow, on average about 2 m. slightly decomposed fuscum, complex, hollow types of structure predominate.

Kondinsky peat-bog area It is a vast alluvial and lacustrine-alluvial plain composed of layered sandy and clay deposits. For the left bank of the river The presence of a ridged relief is characteristic of the Konda and the right bank of its lower reaches. The area is characterized by extremely high watering. A significant part of the Kondinsky region is confined to the area of ​​intense tectonic subsidence and, therefore, is characterized by the predominance of accumulation processes and the dominance of poorly drained swamps. Only the western part of the region, where denudation processes predominate, is characterized by low waterlogging. The riverbeds are slightly incised. In the spring, the hollow waters of these rivers overflow widely and do not enter the banks for a long time. Therefore, the river valleys are swampy for a long distance; near-terrace swamps are strongly flooded during floods. For the river basin Konda is characterized by the predominance of raised ridge-lake, ridge-lake-hollow and ridge-hollow peat deposits.

Lowland, sedge, reed, reed grass, birch-reed grass peatlands are confined to river beds.

Transitional sedge-sphagnum, tree-sphagnum and sphagnum bogs are found along low terraces and in places where they are articulated into bog systems. There are also complexes that form along the lines of the surface intrafallow runoff of swamp waters.

The gradual tectonic subsidence of the surface affects the extremely high watering of the territory, which contributes to the intensive development of regressive phenomena in the swamps, the destruction of the sphagnum sod of ridges, hollows, an increase in the area of ​​hollows due to the degradation of ridges, etc.

Among the swamps there are a huge number of lakes. Some of them are completely covered with peat, but most of them have preserved an open water surface among peaty shores.

In the river basin Kondy, the main type of peat deposit is raised, which is dominated by a complex type of structure, which is due to the dominance of ridge-hollow complexes. Fuscum, Scheuchzerium-sphagnum and Magellanicum deposits are somewhat less common.

Transitional types of deposits compose peat bogs mainly of the second terrace of the river. Konda and its tributaries, and also occur along the edges of upland peat deposits, around mineral islands, or are confined to mesotrophic grass and moss swamps. The most common type of deposit is transitional fens.

Low-lying deposits are found in floodplains, forming narrow strips confined to the overgrown rivers of raised bogs.

The analysis of spore-pollen diagrams dates the Konda peatlands to the Early Holocene. The peat bogs have an ancient Holocene age, the deposit depth of which exceeds 6 m.

Middle Ob peat-bog region It is a lacustrine-alluvial and alluvial plain composed from the surface mainly of cover deposits underlain by either lacustrine layered clays or light loams, siltstone and sandy strata.

The territory is characterized by the development of progressive and predominant accumulation processes, which determines the predominant distribution of poorly drained swamps and constantly swampy forests. Only in the north of the region, where denudation processes predominate, are relatively drained swamps found.

The area is characterized by the dominance of raised sphagnum bogs with ridge-lake-hollow and ridge-hollow complexes. Marsh margins located at lower hypsometric levels (within the first floodplain terraces and floodplains of small lakes) are usually eutrophic or mesotrophic. The deposit of their central parts is represented by fuscum and complex types of structure and has a depth of 4-6 m.

Large peatlands on the watersheds of the first order are divided into three categories. On flat, level plateaus of watersheds, peatlands have a strongly convex surface with steep slopes and a flat central part. The difference in the levels of the center and edges is 4-6 m. The central main part of such peatlands is represented by a fuscum-deposit or complex upland and bears on the surface lake-denudation or ridge-lake vegetation complexes, and on the slopes - ridge-hollow.

On one-sidedly elevated watersheds with a gently concave asymmetric surface, high-moor peatlands show a drop in surface marks from an elevated slope to a lower one.

The thickness of the peat layer also decreases in the same direction. The deepest part of such peatlands is usually represented by a fuscum-type structure with a ridge-lake complex of vegetation on the surface. In the direction to the opposite slope of the watershed, the fallow passes into a complex upland one with a ridge-hollow complex in the vegetation cover. A shallow peripheral area with a transitional marsh deposit bears the vegetation of sphagnum marshes on the surface.

On symmetrical watersheds with a flat plateau, sometimes high-moor peatlands with a complex surface line are observed: two evenly elevated caps are separated by a trough up to 2-3 m deep. Such peatlands are composed mainly of high-moor fuscum or complex peat. Vegetation cover on the gangs is represented by a ridge-lake complex, in the area of ​​the trough - by sphagnum swamps, often giving rise to rivers. A. Ya. Bronzov explains the formation of such massifs by the confluence of two (sometimes several) peat bogs with separate swamping centers. In some cases, the formation of a trough could occur as a result of the breakthrough and outpouring of intradeposit waters and partially the most liquefied and plastic peats from the peat bog, followed by subsidence of the peat deposit.

On watersheds of the second order, peatlands occupy interfluves that have undergone significant dissection. The depth of the erosion incision here reaches 20-30 m. This is the nature of the watersheds between large rivers, flowing approximately parallel to each other in their middle reaches.

In upland conditions, on the watersheds of the occurrence, there are large peat deposits of the raised type with a predominance of fuscum deposits and with ridge-lake and ridge-hollow complexes of vegetation on the surface.

Basically, the Middle Ob region, as well as the Vasyugan region located to the south, are territories of almost continuous swampiness. The swamps here completely cover the watersheds of the first and second orders, terraces and floodplains. High-moor peatlands predominate, the total area of ​​which is about 90%.

Tym-Vakh peat-bog region occupies the Tym-Vakh interfluve and is composed of lacustrine-alluvial deposits. Geographically, it is confined to the Middle Vakh Plain and is characterized by high swampiness, which drops sharply in the northeastern part, where surface elevations reach 140 m.

Poorly drained raised sphagnum bogs with ridge-hollow-lake and ridge-hollow complexes dominate watersheds and fourth terraces. They are also found on low terraces and are confined to the hollows of the ancient runoff, where accumulation processes predominate. The deposit is characterized by great homogeneity and is composed of complex high-moor, Scheuchzerian and Fuscum peat.

The deposit of transitional swamps is represented by transitional marshes and forest-marsh types of structure. Lowland peatlands are rare and are confined mainly to floodplains and low terraces. The deposit of lowland bogs is composed of sedge peat.

Ket-Tymskaya peat-bog region occupies the interfluve of the Keti and Tym and extends east to the Yenisei. The watershed of the Ob and Yenisei has a clearly pronounced slope here with an increase in surface elevations to the east. The interfluves are composed of lacustrine-alluvial and deluvial deposits and are divided by a highly developed hydrographic network into a large number of small interfluves.

Due to the fact that the area is located within the contour of positive structures, the predominance of denudation processes causes the spread of well-drained swamps here. Regressive phenomena are less pronounced, there is a tendency for transgression of ridges, or ridges and hollows are in a state of dynamic equilibrium. The surface of the interfluve plateau has a clearly expressed crested relief. In some places, the dissected relief is leveled by a peat deposit 2-6 m deep fuscum - or a complex type of structure on the ridges, and in depressions - a transitional marsh or mixed marsh deposit with a lower horizon of lowland sedge peat 1.5 m thick. Some ridges are manes, towering above a peat deposit that fills depressions between ridges by 2-10 m. The width of ridges is up to 5 km. They are composed of sandy deposits and are usually overgrown with taiga forests of pine, fir, cedar, and birch. The peatlands of the depressions between ridges are represented by transitional marsh and mixed marsh types of structure. On the upper part of the slope of the watershed to the floodplain in the lower reaches of the Keti and Tyma rivers, there are frequent small rounded peatlands of suffusion depressions (from 10 to 100 ha, rarely more) with transitional and upland, less often with low-lying deposits.

The slopes of the watersheds are eroded, weakly dissected or almost undivided by ledges of terraces, covered with a cloak-like peat deposit, forming large peat bogs that stretch for long distances along the course of both rivers. Closer to the bottom of the watershed, these peatlands are composed of a low-lying deposit, higher up the slope - transitional, and in the upper parts of the slope - upland. Rather large lakes with sapropel deposits at the base are scattered on them, more often in the upper part of the slope, among the upper deposits.

In the upper reaches of the Keti and Tyma rivers, narrow terraces of both river valleys are covered with peat. Narrow peatlands stretched along the rivers are more often composed of transitional deposits. Raised slightly watered pine-shrub-sphagnum bogs are confined here to the watershed plain. The ridge-hollow complex is developed in the central parts of the largest peat bogs.

Lowland and transitional swamps are widespread on the first and partially on the second terraces of the river. Obi. Especially a lot of mesotrophic and eutrophic sedge, sedge-sphagnum, sedge-hypnum, tree-sedge bogs are found on the right-bank terraces of the river. Ob, between the rivers Ketyu and Tym. The average thickness of raised bogs is 3-5 m, lowland 2-4 m. Raised bogs are composed of fuscum, complex and Scheuchzeria-sphagnum types of structure. The deposit of mesotrophic swamps is represented by transitional marsh and forest-marsh types of structure. The deposit of lowland bogs is composed of sedge peat.

In the modern vegetation cover of swamps with a transitional deposit, one can observe an admixture of oligotrophic species, indicating the transition of peat formation to the stage of the oligotrophic type.

A feature of the Ket-Tym region is the significant distribution of transitional and low-lying peatlands in comparison with other peat-bog areas of the forest zone, where the dominants are exclusively raised bogs.

Tavda peat-bog region It is a flat, in some places gently undulating plain, composed of lacustrine-alluvial and alluvial sandy-loamy deposits.

Geographically, its central part is confined to the southern half of the Khanty-Mansiysk lowland, where accumulation processes predominate and the greatest swampiness takes place. In the northwestern outskirts, it enters the limits of the Tavdo-Konda Upland, and in the south - the Tobol-Ishim Plain. The swampiness of the area is high. A significant area is occupied by poorly drained lowland peat deposits, the deposit of which is composed mainly of sedge and sedge-hypnum types of structure with a small participation of deposits of forest-marsh and forest subtypes. The thickness of the deposits is small (2-4 m), occasionally there are peat deposits with a depth of 5 m. On flat watersheds, small raised-type peat bogs are common with deposits 6-7 m thick, often composed of peat of a low degree of decomposition almost to the mineral ground fuscum. There are many lakes on the surface of peat deposits, which at one time served as the centers of formation of the majority of peat deposits in the region.

Vasyugan peat-bog region is a vast, slightly elevated plain, experiencing tectonic uplift. It is composed of alluvial and subaerial sandy-loamy deposits. In the north and east of the region, lacustrine-alluvial deposits are widespread; in the south, subaerial loess-like loams enter its limits. The confinement of the area to the contours of positive structures determines the distribution of relatively drained swamps. Weakly drained swamps occupy the Demyan-Irtysh interfluve and depressions of the Ob-Irtysh watershed, where accumulation processes are developed.

In general, the area is characterized by high swampiness (up to 70%), especially its western part, where swampiness reaches 80% in some places.

Raised sphagnum bogs with ridge-hollow-lake and ridge-hollow complexes are confined to the flat tops of the watersheds. The slopes are less swampy. From the periphery, watershed raised sphagnum bogs are bordered by transitional sphagnum, grass-sphagnum areas of bogs. The deposit of raised bogs is composed of fuscum, complex, hollow and Scheuchzerian types of peat. The stratigraphy of lowland and transitional bogs is dominated by sedge and woody-herbal peat species.

In the middle part of the watersheds, low-lying slope deposits occur in very flat depressions. They are moistened by groundwater such as perched water from higher sections of the watersheds. At the base of the peat bogs lie deoxidized silty calcareous loams, enriching the deposit with a significant amount of mineral salts. The nature of the vegetation cover indicates that a hard water regime is currently taking place. The peatbog deposit is represented by sedge-hypnum and hypnum types of structure. The thickness of the deposit is from 1.5 to 4.5 m.

Their areas are small, and they alternate with areas of sedge and swamp type of structure with a deposit depth of 1 to 3.5 m. types of structure with a deposit thickness of 1 to 2.8 m.

Upland areas in the form of islands lie among the low-lying deposits. Their peat stratum is represented mainly by the fuscum type of structure and reaches a thickness of 6 m. The world's largest watershed heterogeneous peat deposit "Vasyuganskoye" with an area of ​​over 5 million hectares is located in the region. Low-lying peatlands do not form at all in large areas and, in addition to the slopes of watersheds, occupy mainly elongated areas in river valleys.

Low-lying sedge-hypnum bogs predominate on low terraces, which are heavily waterlogged, while low-lying and transitional woody-sphagnum, woody-herbaceous bogs develop in the terraced part. The floodplains are swamped mainly in the upper reaches of the rivers, where low-lying sedge, sedge-willow, tree-sedge and forest bogs are formed. In their canopy under birch canopy, Carex caespitosa and C. wiluica form high tussocks; there is a large amount of forbs in the depressions between tussocks.

Transitional type deposits are located either at the contact of upland deposits with wetland forests, or at the contact of upland and lowland areas. In both cases, these are most often heavily watered deposits with a thin peat layer (1.5–2 m) and vegetation cover of herbaceous plants (Carex lasiocarpa, C. rostrata, Scheuchzeria palustris) and hydrophilic sphagnum mosses (Sph obtusum, Sph. majus, Sph. fallax, Sph. jensenii), forming a smooth semi-submerged carpet.

The thickness of the peat layer in floodplain peatlands does not exceed 1.5-2 m. Their deposit of sedge, Scheuchzeria, wood-sedge or birch peat was in conditions of variable moisture with the participation of river waters, therefore its ash content is relatively increased.

Vasyugan region is characterized by intensive peat accumulation. The average thickness of peat deposits is 4-5 m. Their age dates back to the early Holocene. The areas of swamps up to 8 m deep have the Old Holocene age.

Ket-Chulym peat-bog area characterized by less peatiness compared to the Ket-Tymskaya, which finds its explanation in the geomorphological features of the area. The watershed Ket-Chulym plateau has a much greater degree of erosional dissection under the influence of the main water arteries. The rivers here cut deeply into the surface of the watersheds and have well-formed but narrow alluvial terraces. This caused a decrease in groundwater. Therefore, the total peat content in the Ket-Chulym region is reduced to 10%.

The relief of the watershed Ket-Chulym plateau is characterized by small saucer-shaped depressions of suffusion origin. They predetermine here basically

location and type of peatlands. The most widespread in peat bogs of suffusion depressions is the transitional marsh deposit with a total thickness of the peat layer from 1 to 4.5 m. Raised deposits are less common in them, mainly fuscum, complex and Scheuchzeria-sphagnum with a depth of up to 3-6 m. 1-2 m deep are occupied by cottongrass-sphagnum or Magellanicum-deposit. Lowland deposits in suffusion depressions are rare and are represented by forest, tree-sedge, multilayer forest-marsh and sedge types of structure. They fill the deepest hollows, in which the thickness of the peat suite reaches 4-5 m.

In the Ket-Chulym region, there is a certain regularity in the placement of near-terrace peat deposits. In the middle part of the river Ulu-Yul peatlands are small and located on sharply defined terraces. Downstream the river, the terrace ledges are smoothed out, the surfaces of the terraces are expanding, and the areas of peat deposits are also increasing. The latter acquire an elongated shape and are extended parallel to the river. Near the mouth of the river Ulu-Yul terraces are even weaker and peat deposits merge with each other, covering the surface of several terraces.

On terraces and in the terraced parts of river valleys, peat bogs are smaller in size (compared to the peat bogs of the Ket-Tym region) and, without merging into massifs of great length, form on the terraces chains of disconnected deep-lying peat deposits extended parallel to the river, often of lowland type with forest, tree-sedge or sedge deposit.

Tura-Ishim peat-bog area is a lacustrine-alluvial plain composed of sandy-loamy deposits and is characterized by the predominance of denudation processes. The swampiness of the region is high. Lowland bogs dominate: sedge, sedge-hypnum, birch-sedge. Raised pine-sphagnum bogs occupy insignificant areas. The most waterlogged central parts of the interfluve are occupied by raised ridge-hollow bogs.

In general, this area is highly swampy, slightly dissected, gently flat, wide river valleys with large low-lying sedge-hypnum bogs at the foot of the terraces and along their slopes, and with medium-sized high-moor and transitional peat bogs on the watersheds. The total swampiness of the region is up to 40%.

An example of a peat deposit of the first floodplain terraces is Tarmanskoye, located in the valley of the river. Tours. It stretches along the river for up to 80 km and adjoins the ledge of the bedrock bank. Its deposit is almost entirely composed of sedge-hypnum and sedge peat, confirming the existence of subsoil nutrition.

The deposit includes within its boundaries a significant number of primary lakes of a rounded-elongated shape with an emerging orientation along the terrace. At the base of the lakes there are highly mineralized sapropels, which indicates the forest-steppe conditions during the formation of the lakes. In the lower horizons of the deposit or on the margins of the deposit, a high ash content of peat is observed as a result of clogging of the deposit with deluvial drifts.

North Baraba peat-bog region watershed sedge-hypnum bogs in the north borders on the Vasyugan peat-bog region, in the south on the South Baraba and is a gently undulating, slightly dissected plain. The region is composed of loess-like loams. The porosity is small. It is dominated by medium-sized low-lying peatlands of the type of borrowings with an area of ​​10 to 100 ha. The eastern margin, confined to the positive contours of the structures, is characterized by the development of relatively well-drained swamps. More than half of the peaty area is low-lying peatlands (54%) and about 27% is raised; the percentage of transitional peatlands is relatively high here (19%).

There are many lakes, depressions and peat deposits in the central part of the region. In the western part of the region, on the slopes of the Tara-Tartas interfluve, the main area of ​​sedge-hypnum bogs is concentrated. Hypnum swamps develop in low relief elements, mainly in the places where ground hard water flows emerge, along the slopes of watersheds or in the terraced parts of river valleys. Therefore, a slightly increased ash content (up to 8-12%) is inherent in hypnum peat and peat deposits. The ash content of some terraced hypnum peatlands averages 6-7%. The ash content of the sedge-hypnum peat bogs of the Tara-Tartas interfluve is also measured by the same percentage.

To the east, sedge-hypnum peatlands yield their leading position in the lowland type to forest-marsh and forest deposits. The latter are located here along the edges of peat deposits, in the central sections of which, as well as in areas with a more elevated bottom relief, there are islands of upland deposits. Moreover, the fuscum fallow is usually peripheral in relation to the complex upland, which is located in the center, carrying a ridge-lake complex of vegetation on the surface.

Despite the increased carbonate content of the underlying rocks, the relatively low occurrence of groundwater, atmospheric precipitation, and partial uplift of the territory create favorable conditions for the gradual transition of lowland bogs to the oligotrophic stage of development. In the river valleys immediately adjacent to the river ridges, the richest in floristic composition woody-grass bogs (sogry) are common. In that part of the valley where anoxic groundwater flows and deluvial waters do not penetrate, sedge-hypnum bogs are formed. In addition to typical moss, there are sedge and sedge-grass bogs, and in the east - reed bogs, characteristic of the grass bogs zone.

In the riverine parts of the watersheds, along the banks of the upper reaches of the rivers, in the depressions of the terraces, transitional forest swamps are widespread. Watershed lowland sedge-hypnum and hypnum bogs usually have a simple structure and are composed of sedge-hypnum and sedge peat species. The presence of ryams (upper sphagnum islands) is a characteristic feature of the sedge-hypnum bogs of the North Baraba region. The hypnum deposit is more characteristic of swamps of low terraces, where soluble calcium salts predominate in water and mineral nutrition. The bog deposit of the watershed plains differs from the peat bog deposit of low terraces in terms of high rates of decomposition and ash content, which has a more complex stratigraphy. There are grass-hypnum, cottongrass-sedge, reed-sedge, reed-sedge, sedge-sphagnum types of peat.

The bottom layers of the deposit are usually composed of reed or sedge-reed types of structure. Peat species of the woody group take a significant part in the structure of the deposit of lowland near-terrace and floodplain-terrace bogs. Transitional forest swamps are widespread. They are formed in the interfluves, in the terraces above the floodplains and in the terraced parts. The deposit of these swamps is represented by transitional forest and forest-marsh types of structure.

In the pits, the upper horizons of the deposit (up to 2-4 m) are represented by fuscum-peat with separate layers of magellanicum, angustifolium, cotton grass-sphagnum, pine-cotton grass and pine-shrub peat species. The bottom layers of the deposit are usually represented by peat of transitional and lowland types. The average depth of the peat deposit on the watersheds is 2-3 m; on low terraces, the peat thickness increases to 5 m compared to the Vasyugan region. The beginning of the peat-forming process dates back to the early Holocene.

Tobol-Ishim peat-bog area located west of the river. Irtysh and crosses the interfluve of Ishim and Tobol in the middle reaches. The surface of the territory is quite dissected and well-drained. The swampiness of the region does not exceed 3%. It is dominated by small low-lying swamps of the type of borrowings with an area of ​​10 to 100 hectares. The confinement to the positive contours of the structures determines the development of predominantly well-drained peat deposits here.

The hryvnia nature of the relief, a poorly developed hydrographic network, a waterproof horizon close to the surface, and a slow runoff of surface waters led to the formation of a huge number of lakes, usually rounded or oval, with shallow depths, a flat bottom and strong overgrowth, in the interhume spaces. The lakes are often adjoined or surrounded by small-sized shallow sedge-reed bogs-bogs. During the period of snowmelt, the lakes are flooded with melt water, turning into temporary shallow water bodies, often interconnected, and then the flow through such a chain of lakes connected by lakes has the character of a river. There are very few isolated lakes. According to the chemical composition of the waters of the lakes, sometimes located in close proximity to one another, they are distinguished by considerable diversity. Nearby lie salty, bitter and fresh lakes.

Relatively larger occupants typical of the northern part of the region are surrounded by lakes with fresh and brackish water. The thickness of these deposits is up to 1-1.5 m. It is composed of highly mineralized sedge, sedge-reed and reed peat with an average ash content of 20-30%. Their vegetation cover is dominated by reed, reed-sedge and sedge (C. caespitosa, C. omskiana) phytocenoses.

Less large-sized borrowings are common in the southern part of the region around salt lakes. They are very shallow, composed of reed peat with a high degree of decomposition and high ash content. The reed association, less often the sedge association, dominates in their vegetation cover.

On the sandy expanses of the Tobol region and in the northern part of the region on the right bank of the Ishim, low-lying peatlands (sedge and sedge-hypnum) have separate areas (such as ryams) with raised deposits composed of fuscum-peat of a low degree of decomposition, with a convex surface and a secondary vegetation cover of pine- shrub phytocenosis, formed as a result of repeated fires.

In small basins of suffosis of ionic origin, there are shallow "chopping" peat bogs of the lowland type. They developed in solonetz microrelief depressions - "saucers". Salinization and the subsequent process of bogging leads to the appearance in them of areas that are exclusively characteristic of this area of ​​marshy meadows with Carex intermedia, which are subsequently covered with thickets of shrubs, mainly Salix sibirica, and birch stands.

There are also treeless "choppy" swamps with sedge hummocks on the surface, surrounded by tall birch along the periphery. They formed in deeper and more humid depressions with diverse wetland vegetation, which varies greatly in composition in some cases: with tussocks of Carex omskiana, sometimes with Salix sibirica in the shrub layer. Such peatlands are never covered by birch over the entire area; the deposit in them is tree-sedge.

South Baraba peat-bog region large peat-ryam bogs are composed of alluvial-lacustrine and loess-like deposits. Its soil cover is dominated by peat-bog soils, solonetzes and solonchaks (up to 60%); a smaller area is occupied by chernozems, podzolic soils, etc.

The processes of salinization of soils (including peat ones) are widely manifested in the region. Their mineralization naturally increases from north to south. The general calm relief of the region is complicated by low ridges elongated in a southwestern direction in combination with depressions between ridges. The hydrographic network is quite dense. Both lakes and river beds are abundantly overgrown with aquatic and wetland vegetation and imperceptibly merge with wetlands. Very often, depressions between ridges are completely swamped. The relief of Baraba is characterized by suffusion depressions on various surface elements and a large number of lakes, different in size, origin and chemical composition of water.

The swampiness of the area is approximately 33%. Low-lying reed-sedge peatlands predominate here, accounting for up to 85% of the total wetland area. The remaining 15% is distributed between the upper deposits of the ryams and the transitional deposits of their peripheral areas.

Zaimishchno-ryam peat bogs are most common in the eastern half of the region, their area reaches several thousand hectares here, and the area of ​​ryams - high, rising up to 8-10 m above the level of the occupant - up to a thousand hectares. In the direction to the west, the areas of borrowings decrease, ryams are less common, their height decreases.

The occurrence of high-lying deposits of ryams among the low-lying deposits is associated with the supply of ryam sites with fresh and slightly saline lacustrine or surface stagnant waters. The lakes are still preserved as open reservoirs adjacent to the ryams, sometimes traces of them remain at the base of the ryam deposits in the form of a thin layer of sapropel.

The degree of decomposition of borrowing peat, as a rule, exceeds the species index (30-50%), the average ash content is 20%. The deposit of borrowings is composed of highly mineralized peats of the swamp group: reed, reed-sedge and herbaceous (with a predominance of remains of svetluka and reed grass in the fiber). The total thickness of the borrowing deposits reaches 1.5 m. In the vegetation cover, reed, sedge-reed and sedge (or grass-sedge) phytocenoses are successively replaced in the direction from the center to the periphery. The latter borders on solonchak meadow vegetation. The areas fed by lake waters did not feel any variability in moisture and salt regime. Protected from the influence of saline groundwater by the low-lying deposits surrounding them, they were overgrown with Sph. teres, water bodies passed into the stage of a peat bog, gradually, as the deposits grew, they got out of the influence of lake waters and continued to develop as peat bogs of atmospheric nutrition. The dominance of Sph. fuscum maintains a regime of high humidity and low temperature in the deposit. sp. fuscum created its own substrate and microclimate even in forest-steppe conditions, and over the course of millennia it deposited powerful deposits of high-moor peat.

The modern vegetation cover of the ryams is secondary and arose under the influence of man. The degree of decomposition of the Fuscum deposit is always low, which, in addition to high humidity and low temperature, apparently contributes to its increased acidity, which inhibits microbiological processes. At the contact of the ryams and the borrowing proper, there is usually a belt of transitional fallow with a mesotrophic vegetation cover.

In addition to large borrow-ryam peat bogs, the South Baraba region is characterized by numerous small peat bogs in saucer-shaped depressions and depressions of suffusion origin along interfluves and ridges.

Transitional and lowland forest swamps usually form a narrow belt around ryams or are confined to mesorelief depressions. In the latter case, forest swamps are genetically related to birch groves. Kolochny bogs with a predominance of Carex intermedia are typical of the southern part of the region. Birch-reed bogs here are confined to flat, highly mineralized lowlands and represent one of the initial phases of bogging. The total area of ​​the ryams is insignificant. They are found mainly in the northern half of the region.

According to the radiocarbon method, the absolute age of the 3.1 m thick ryam is dated to the Middle Holocene, and the 1.35 m deep deposits are dated to the Late Holocene. The swamping processes are promoted by the gradual tectonic uplift of the area, which causes the disintegration of rivers and lakes into separate reservoirs.

East of the river Yenisei within the Asian part of the Union, seven large natural geographical areas are distinguished.

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The West Siberian Lowland, which extends into Russia, in Western Siberia, is one of the three largest plains on our planet in terms of area. The natural wealth extracted in its regions is truly limitless.

The West Siberian Plain has a significant territory in Russia (here it occupies 2.6 million km 2 of the total area of ​​more than 3 million km 2) and is partially included in the Kazakh expanses. At the West Siberian Lowland (as the plain is also called), the length from the northern to the southern limits is about 2500 km, and from the western to the eastern borders - from 1 thousand km to 2 thousand km.

Its boundaries:

• in the south direction: with the Turgai dining country and Saryarka;
• in northern parts: with the Arctic Ocean;
• in the western direction: with the Urals;
• in the east: with the Central Siberian plateau along the Yenisei river valley;

Theory of education, the age of the plain

The plain is based on a young platform. It was formed in the Paleozoic (570-240 million years ago), while the Altai Ranges were formed during the Caledonian (490-360 million years ago) orogeny.

West Siberian Plain - characteristics and features.

Stages of formation of the West Siberian Plate:

1. It began to form in the Upper Jurassic period (152-157 million years ago). Then, during the breaking and rebirth of the plate, a giant territory (approximately between the Urals and the Siberian platform) sank, which led to the emergence of a sedimentation (in which sedimentation occurs) basin. In the course of its development, the West Siberian Plate was repeatedly captured by the sea advancing on land as a result of the subsidence of the earth's crust or the rise in sea level.
2. At the end of the Lower Oligocene (the period from 33.9 to 23.03 million years ago), the sea left the West Siberian plate, and it became a giant lacustrine-alluvial (alluvial) plain.
3. In the middle and late period of the Oligocene and in the Neogene (23.03 - 2.58 million years ago), the plate rose in the north, but at a later time (from 2.6 million years and later) it sank.

The plate developed during the subsidence of vast expanses, which indicates the likelihood of oceanization not completely completed, and this is emphasized by very strong waterlogging.

Relief and landscape

The West Siberian Plain has a very uniform relief. Its predominant part is below 100 m above sea level. Alluvial-lacustrine and accumulative (formed as a result of uneven accumulation of river, lacustrine, marine and other sediments, products of volcanic activity) reliefs are more common.

In the southern part, a denudation relief is observed (formed during the transfer of weathered rocks from elevated areas of the terrain to lower ones).

Extensive floodplains and huge swamps are characteristic, mainly in the north. The relief, formed by the influence of glaciers and the advance of the sea on land, is noted north of the Ob River. Severe soreness. Salt accumulation is observed mainly to the south. In the north, the uniform flat relief is disturbed by elevations up to 200-300 m.

The accumulation of peat is typical for swamps. Sandy upper layers are subject to deflation (fluttering and wind blowing of particles of loose rocks, snow, as well as their transfer and grinding during transfer). Permafrost (the thickness of the frozen layer is up to 600 m) is observed in Yamal and other peninsulas.

To the south, the area of ​​relief created by the activity of glaciers is adjacent to lacustrine and lacustrine-alluvial plains. Between the rivers Tobol and Irtysh is the sloping Ishim plain.

Natural areas are marked in the landscape:

Tectonic structure of the plain

The tectonic structure of the plain is based on the West Siberian young plate. Its foundation was formed from richly distributed Paleozoic deposits. On top they have loose continental and marine rocks of the Meso-Cenozoic with a thickness of more than 1 km.

The latest deposits are in the southern part, they are anthropogenic - lacustrine and alluvial, often hidden by loess (mountain loose porous rocks) and loess-like loams.

In the north of the deposit:

• glacial;
• marine;
• ice-sea (there are more than 4 km thick).

Climate

The West Siberian Lowland has a continental climate, typical of the interior regions of large continents. On the plain, zonality in latitudes is clearly manifested. The features of the weather regime are strongly affected by the Arctic Ocean.

The nature of the winter climate in the plain

Indicators observed:

	polar latitudes	central part	southern part
Duration winter months	Up to 8; around 3 - polar night	Around 7	5-6
Average t January, ᵒ С	– 23 – 30	–19 –22	–18 –22
Time of snow cover	8-9 months	Fluctuates between digit values ​​at other latitudes	5-6 months

Features of the summer climate

In summer, Atlantic air masses come from the west. At the same time, cold air comes from the Arctic, and from the southern regions, Central Asia - its warm and dry streams.

The nature of summer in the plains:

• northern: short, cool, with an abundance of precipitation;
• central: warm and moderately humid;
• southern: arid, with lack of moisture; characterized by dry winds, dust storms.

The air in the middle of summer usually warms up to values: from +5 ᵒС in the north to +22 ᵒС - to the south. Precipitation occurs mainly in summer, with the greatest amount of up to 600 mm per year. This is seen in the forests. In other zones, to the south and north, the amount of precipitation becomes less, reaching up to 250 mm during the year.

Rivers

More than 2 thousand rivers drain the plain. Their total length is over 250 thousand km. The total flow of water is 1200 km3 per year. The rivers are fed by melted snow and rainwater. Therefore, the water runoff is most voluminous in the summer and spring months (70-80% of the annual amount). In winter, the rivers freeze, at this time the annual flow is about 10% of the total volume.

Large rivers of the plain are navigable. They have significant reserves of hydropower resources.

All rivers of the plain are characterized by a low flow rate and slight slopes.

Ob

This is a very significant, high-water river, one of the greatest water arteries of the earth. The length of the Ob is 3676 km. The area of ​​the basin is approximately 3 million km2. After joining the Irtysh River, the Ob's water flow acquires a width of up to 3-4 km. Near the mouth it reaches 10 km, the depth reaches 40 km.

The main tributaries of the Ob:

• Irtysh;
• Vasyugan;
• Northern Sosva;
• Chumysh;
• Ket;
• Big Yugan;

other.

Irtysh

This is the most significant tributary of the Ob. Its length is 4248 km. The area of ​​the basin is 1643 km2. It starts in the mountains of Mongolia. For a long period, the Irtysh has practically no tributaries. Then, in the taiga area, the Tobol, Ishim and other large rivers flow into it.

Yenisei

It flows near the eastern border of the West Siberian Lowland. This water artery is the most abundant in Russia. The length is 4091 km. The area of ​​the basin is about 2.6 km2. The river begins in the Tuvan Republic. There are rapids in the middle and upper currents. Below, when the Lower Tunguska flows into the Yenisei, the speed of water movement weakens. Islands of sand loomed in the riverbed.

The Yenisei River flows into the bay of the Kara Sea, called the Yenisei Bay. In the lower reaches, the depth of the river reaches 50 km. Therefore, seagoing vessels can rise through the waters further than 700 km without interference.

The main tributaries of the Yenisei:

• Angara;
• Lower Tunguska;
• Stony Tunguska.

The Krasnoyarsk and Sayano-Shushenskaya hydroelectric power stations were built on the river.

Taz

Flows in the Yamalo-Nenets Autonomous Okrug. It starts on the Siberian Ridges from the raised bog. It flows into the Taz Bay, while forming a multi-branched delta. Length - 1401 km. The area of ​​the basin is 150 thousand km2. The width of the channel in the lower reaches reaches 1000 m, the depth is up to 14.5 m.

lakes

The West Siberian Plain is unusually rich in lakes, there are approximately 1 million of them. Their total area exceeds 100,000 km 2.

The largest lakes:

• Vats;
• Small Chans;
• Kulunda;
• Sartlan

other.

There are many salty, bitter-salty and self-sustaining lakes (with a very high salt content). In the north of the lowland, there are often lakes with thermokarst origin. There are many small lakes, the area of ​​each does not reach 1 km2.

Flora

Due to the vast area of ​​the West Siberian Plain, many types of vegetation can be distinguished that grow in various natural zones.

Some are listed in the table:

polar desert	grains are yellow; poppies; forget-me-not blue
Tundra	orange lights; blueberry; underline; mytniki purple; prince; white bells; alder; marsh wild rosemary; buttercups; cloudberry; valerian rose; cowberry
Forest-tundra of Siberia	bearberry; a huge amount of green moss; dwarf birch; shrub centra; underline; lichens; klyadoniy shrub
woodlands	stunted trees; cloudberry; cranberry; blueberry
Mountain forest belt	Siberian fir (predominant); pine; larch; aspen; Birch; kurai willow; myricaria; sea ​​​​buckthorn; shrub cinquefoil; Rowan; currant
Aspen-birch forests	aspen; warty birch; orchids; violets; cyanosis; meadowsweet; burnet; tansy; strawberry
Taiga	pine; Birch; cedar; larch; juniper; poplar; hemlock; alder; rose hip; blooming Sally; cowberry; cranberry; wild rosemary; cere; lichens;
Steppe	alfalfa; sagebrush; thyme; bloodroot; bird cherry; cane; tape burs; irga; Birch

Fauna

The animal world is also very diverse.

About 500 species of vertebrates have been identified here, of which the species are:

• mammals - 80;
• birds - 350;
• amphibians - 7;
• fish - 60.

You can roughly describe the fauna in the table:

polar desert	Because of the permafrost, the fauna of this zone is limited. Meet: lemming; arctic fox; polar bear; owl; duck; gull; deer
Tundra	The same animals are found as in the polar desert, and others: wolf; killer whale; wolverine; sea ​​lion; white hare; seal; ermine; musk ox; white partridge; white whale; tundra swan; loon; oatmeal crumb; White Crane; peregrine falcon; lark;
Forest-tundra of Siberia	Animals of the polar desert live and such: sable; capercaillie; woodpecker; sandpiper; Elk; marten; caress; ermine; fox; wolf; partridge; otter; lynx; goose; swan; great snipe; crane; thrush
woodlands	Many inhabitants of the forest-tundra are noted (the first 5 in the table) and: squirrel; Brown bear; nutcracker; grouse;
Mountain forest belt	There are inhabitants of woodlands, as well as: roe; Mountain goat; deer; mink; lynx; wolverine; otter; chipmunk; crossbill; jay
Aspen-birch forests	water rat; white hare; hare-hare; squirrel; Elk; badger; Brown bear
Taiga	Replete with previously listed representatives of the fauna - rodents, predators, birds
forest-steppe zone	There are different types of rodents, also: flying squirrel; Elk; caress; boar; ermine; ferret; fox; muskrat; boar; badger; roe; duck; swan; black grouse;

The ichthyofauna is extremely rich.

Here are just a few types of fish:

The groundwater

The West Siberian artesian megabasin is a huge reservoir of fresh groundwater with an area of ​​almost 3 million km3. The geological reserves of fresh groundwater for household and drinking purposes are over 65 thousand km 3.

2 hydrogeological levels of the inner basin are distinguished, separated by a thick layer of marine sediments of a clay character.

In the upper floor in the central areas of the basin and to the north, the waters are mostly fresh, which can be used for water supply. In the south direction of the reservoir, the waters have a more diverse chemical composition. They are mineralized up to 10-15 g/l, which is associated with ongoing continental salinization.

In the lower floor of the artesian basin, the water-bearing layers are saturated, flowing to the surface along the edges of the basin, in the Ob-Yenisei interfluve. In this place, up to several hundred meters deep, there are fresh waters suitable for human drinking and household needs.

From the edges to the central part of the basin, there is an increase in the clay component of sediments, the process of water exchange worsens, and the mineral component of groundwater increases (80 g/l). Hot (reach 150 °C) waters come across at a distance of 2,500-3 km inland.

natural areas

The West Siberian Plain is so large that it includes 5 natural zones plus mountainous and low-mountain regions.

All of them have specific features and are quite clearly separated:

Zones	Peculiarities
Tundra	Celebrated in the north of the Tyumen region Area - approximately 160,000 km 2 No forests There are moss, lichen-sphagnum, lichen and other tundras.
Forest-tundra	It is located in a southerly direction relative to the tundra with an area of ​​​​about 100-150 km, representing an adjacent zone with signs of both taiga and tundra Combines swamps, light forests, shrub thickets
Forest (also can be called taiga or forest swamp)	The strip is about 1000 km long. Territorially includes up to 62% of all Western Siberia It is divided into subzones of the taiga according to the cardinal points: northern, southern, middle The predominant forests of this zone are dark coniferous An important element is swamps, here are the greatest wetlands in the world
Forest-steppe	There are forest and steppe plant communities There are meadows and marshes Solonchaks marked Birch and mixed forests grow (aspens with birches) Forbs observed
steppe	In the west of the Altai Territory, in the south of Omsk, in the Novosibirsk Region Characteristic: flat terrain, grassy vegetation, a minimum of trees
Altitudinal zonality	It is due to the significant height of the mountains. This includes lowland and mountainous areas: Kuznetsk Alatau, in the mountainous region of the Sayan and Altai; Mountain Shoria in the south of the Kemerovo region; the city of Salair, Kemerovo region; AltaiThe presence of a black taiga is typical, as well as a "lime island" about 150 km 2

Minerals

The West Siberian Plain is replete with all sorts of minerals. 140 very large deposits have been discovered within its limits.

Found in the bowels:

• gold;
• platinum;
• titanium;
• iridium;
• chromium;
• zirconium;
• bronze;
• molybdenum;
• silver;
• barium;
• mercury;
• manganese;
• coal;
• natural gas;
• peat;
• limestone;
• cesium;
• brown coal;
• strontium;
• calcium;
• tungsten;
• scandium;
• oil;
• ores.

Oil is produced everywhere in Western Siberia; in 2017, 340 wells were in operation. Marshes provide good ground for maintaining natural gas reserves, storing coal deposits and other valuable hydrocarbons. Very large reserves of shale, oil, and gas have been explored in the open spaces of the Middle Ob Lowland.

The Tazovo-Purskaya lowland is a significant region for the production and processing of natural gas and oil. The Yamal Peninsula is fraught with colossal reserves of "black gold", polymetallic and gas sources. Brown coal, potash salts, and iron ore are also mined here.

Dominant Heights

For the most part, they are not higher than 150 m. The lowest areas of the plain reach 50-100 m. They can be observed mainly in a northerly direction. Such lowlands as the Purskaya, Nizhneobskaya and Nadymskaya with the Kondinskaya and Sredneobskaya hiding in its central part are the lowest in the described geographical area.

The highest point of the plain is determined on the Priobsky plateau. It is located at an elevation of 317 m.

Regions

The Yamalo-Nenets and Khanty-Mansi Autonomous Regions, as well as several regions, are located on the plains:

• Tomsk;
• Tyumenskaya;
• Kemerovo;
• Omsk;
• Novosibirsk.

In these regions, industry is actively operating, enterprises for the extraction and processing of minerals have been set up. Regions often have large areas, often - abundant waterlogging. Partially, the Russian regions of Kurgan, Chelyabinsk, Sverdlovsk, as well as Kazakhstani: Akmola, Pavlodar, Kustanai and others are also located here.

Large cities located on the plain and their features

The largest city is Novosibirsk (about 1 million 500 thousand inhabitants). This is a major transport hub of the country, one of the centers of scientific and cultural life.

Other significant cities of the West Siberian Lowland:

There is industry, engineering. There is an international airport.

Ecological situation and specially protected natural areas

Environmental problems did not bypass the West Siberian Plain:

In the regions of oil production	Due to violations of the integrity of pipelines, oil and products of its processing enter the water and soil
In forestry areas	excessive deforestation; Forest fires; silkworm sabotage; turning land into swamps
In agricultural landscapes	fresh water shortage; violation of the structure of soils and the disappearance of their fertility as a result of plowing, drought, the influence of dust storms secondary soil salinization
In the north	Degradation of reindeer vegetative pastures due to overgrazing

Also topical is the problem of preserving spaces for hunting and habitats for the existence of fauna in nature.

For the purposes of conservation and study of natural landscapes, natural parks, reserves and similar objects have been established, for example:

• nature reserves: Malaya Sosva, Verkhnetazovsky, Gydansky;
• natural parks: Kondinsky lakes, Deer streams, Siberian Uvaly;
• National parks: Pripyshminsky Bory and others.

The value of the plain in Russia and the world

The West Siberian Plain is one of the largest plains on the planet Earth. Here, countless deposits of minerals are stored in the bowels of the earth. Gigantic water resources are concentrated here. The area of ​​swamps in total exceeds 600 thousand km 2, which is much more than the territories of France, Spain or Switzerland.

More than 60% of the oil treasures of this region are concentrated in the swamps, they are also the richest source of fresh water. The colossal reserves of bog peat are capable of sequestering carbon, while hindering the development of the greenhouse effect.

Most of the lowland area is covered by taiga. The forest potential of the West Siberian Lowland is very valuable for the development of the forest industry. Every year these resources are more and more intensively involved in the sphere of economic development. The export of wood and lumber from Russia to other countries is increasing.

There is reason to believe that Western Siberia for Russia is the most prosperous region in terms of natural resources. The region's mineral resources are of commercial value and extremely important to the global economy. They are transported by rail and pipelines to the European part of Russia and further to other countries.

The landscapes of nature in Russia are magnificent and unique. The beautiful West Siberian lowland, which has taken over almost the entire space of Western Siberia, is a plain with the richest mineral, water and forest resources. It is a very valuable region for the Russian Federation and other countries of the world.

Article formatting: Lozinsky Oleg

Video about the West Siberian Plain

Features of the nature of the West Siberian Plain:

The eastern territories of Russian Asia open from the Ural Mountains with a view of the West Siberian Plain. Its settlement by Russians began in the 16th century, from the time of Yermak's campaign. The path of the expedition ran from the south of the plain.

These areas are still the most densely populated. However, it must be remembered that already in the 11th century Novgorodians established trade relations with the population on the lower reaches of the Ob.

Geographical position

The West Siberian Plain is washed by the harsh Kara Sea from the north. In the east, along the border of the Yenisei River basin, it is adjacent to the Central Siberian Plateau. The southeast is guarded by the snowy foothills of Altai. In the south, the Kazakh uplands became the boundary of the flat territories. The western border, as mentioned above, are the oldest mountains of Eurasia - the Urals.

Relief and landscape of the plain: features

The unique feature of the plain is that all the heights on it are very weakly expressed, both in absolute and in relative terms. The terrain of the West Siberian Plain is very low-lying, with many river channels, swampy over 70 percent of the territory.

The lowland stretches from the shores of the Arctic Ocean to the southern steppes of Kazakhstan, and almost all of it is located within the territory of our country. The plain provides a unique opportunity to see five natural zones at once with their characteristic landscape and climate conditions.

The relief is typical for low-lying river basins. Small hills alternating with swamps occupy the interfluve areas. The area with saline groundwater dominates in the south.

Natural areas, cities and plain regions

Western Siberia is represented by five natural zones.

(Swampy area in the tundra of the Vasyugan swamps, Tomsk region)

The tundra occupies a narrow strip of the north of the Tyumen region and almost immediately passes into the forest tundra. In the extreme northern areas, one can find arrays of a combination of lichens, mosses of Western Siberia. The swampy terrain prevails, turning into light forest forest-tundra. The vegetation here is larch and thickets of shrubs.

The taiga of Western Siberia is characterized by dark coniferous zones with a variety of cedar, northern spruce and fir. Occasionally, pine forests can be found, occupying areas between swamps. Most of the lowland landscape is occupied by endless swamps. One way or another, the whole of Western Siberia is characterized by swampiness, but there is also a unique natural massif here - the largest swamp in the world, Vasyuganskoye. It occupied large territories in the southern taiga.

(forest-steppe)

Closer to the south, nature changes - the taiga brightens, turning into a forest-steppe. Aspen-birch forests and meadows with copses appear. The Ob basin is adorned with natural island pine forests.

The steppe zone occupies the south of the Omsk and the southwestern part of the Novosibirsk regions. Also, the steppe distribution area reaches the western part of the Altai Territory, which includes the Kulundinskaya, Aleiskaya and Biyskaya steppes. The territory of ancient water drains is occupied by pine forests

(Fields in the taiga of the Tyumen region, Yugra)

The West Siberian Plain provides an opportunity for active land use. It is very rich in oil and almost all lined with mining towers. The developed economy of the region attracts new residents. Large cities of the northern and central parts of the West Siberian Plain are well known: Urengoy, Nefteyugansk, Nizhnevartovsk. In the south of the city of Tomsk, Tyumen, Kurgan, Omsk.

Rivers and lakes of the plains

(The Yenisei River in hilly-flat terrain)

Rivers flowing through the territory of the West Siberian Lowland flow into the Kara Sea. The Ob is not only the longest river of the plain, but together with the Irtysh tributary, it is the longest waterway in Russia. However, there are rivers on the plain that do not belong to the Ob basin - Nadym, Pur, Taz and Tobol.

The area is rich in lakes. They are divided into two groups according to the nature of their occurrence: part was formed in pits dug by a glacier that passed through the lowland, part - in places of ancient swamps. The area holds the world record for wetlands.

Plain climate

Western Siberia in its north is covered with permafrost. A continental climate is observed throughout the plain. Most of the territory of the plain is very susceptible to the influence of its formidable neighbor - the Arctic Ocean, whose air masses freely dominate the lowland region. Its cyclones dictate the regime of precipitation and temperatures. In the plains, where the arctic, subarctic and temperate zones converge, cyclones often occur, leading to rain. In winter, cyclones generated at the junctions of the temperate and arctic zones soften the frosts in the north of the plains.

More precipitation falls in the north of the plain - up to 600 ml per year. The temperature in the north in January, on average, does not rise above 22 ° C of frost, in the south at the same time frost reaches 16 ° C. In July, in the north and south of the plain, respectively, 4 ° C and 22 ° C.