What are the features of the relief of northeastern Siberia. Lesson topic: "Eastern Siberia: general features of nature." Vegetation and soils

It occupies an area of about 7 million square kilometers. Eastern Siberia is called the area located east of, to the mountains that form the watershed between and. It occupies the largest area. In the north and east there are two lowlands: North Siberian and Central Yakut. In the south and west there are mountains (, Yenisei Ridge). The length of this region from north to south is about 3 thousand kilometers. In the south there is a border with and, and the northernmost point is Cape Chelyuskin.

During the Mesozoic period, most of Central Siberia experienced uplift. It is no coincidence that the highest point of the Central Siberian Plateau is located in this area - (its height is 1700 meters above sea level). In the Cenozoic, surface uplift continued. At the same time, a river network was being created on the surface. In addition to the Putorana plateau, the Byrranga, Anabar and Yenisei massifs rose most intensively. Subsequently, active tectonic processes that took place in this territory led to a change in the river system. Traces of river systems that existed in ancient times have survived to our time. At the same time, river terraces and deep river valleys of the central part of Siberia were formed.

Cape Chelyuskin

The vast majority of river valleys in Central Siberia are canyon-like and asymmetrical. Their characteristic feature is also a large number of terraces (six to nine), which indicates repeated tectonic uplifts of the territory. The height of some terraces reaches 180-250 m. On and in the North Siberian lowland, the river valleys are younger, and the number of terraces is somewhat less. Even the largest rivers have here three or four terraces.

Four relief groups can be distinguished on the territory of the Central Siberian Plateau:

plateaus, ridgesplateaus, ridges, and mid-mountain massifs on ledges of the crystalline basement
bedded uplands and plateaus on sedimentary Paleozoic rocks;
plateau
and reservoir-accumulative

Most of the tectonic processes that took place in antiquity and in modern times, on the territory Eastern Siberia matched in direction. However, this did not happen throughout the entire territory of the Central Siberian Plateau. As a result of these discrepancies, depressions similar to the Tunguska were formed. There is no permafrost (the Lena-Angara and Lena-Aldan plateaus). But the main small relief forms on the territory of the Central Siberian plateau are still erosive and cryogenic.

Due to the strongest monsoons, sharply continental, characteristic of Eastern Siberia, here you can find a large number of stony placers and screes in mountain ranges, on the slopes of river valleys and on plateau surfaces.

Lesson 48 SPECIFICITY OF NATURE

Option 1

Option 2

1) Match: Natural Frontier

a) the Arctic Ocean;

b) Kazakh small hills. Part of the border

south;

north;

west;

East.

The foundation of the West Siberian platform, compared to the East European platform, was formed:

a) earlier;

b) at the same time;

c) later.

The territory of Western Siberia has a general slope:

a) to the north

b) south.

The lower flat relief of Western Siberia is associated with:

a) with a greater depth of foundation;

b) with the features of new movements of the earth's crust.

The increase in the continentality of the climate of Western Siberia is manifested:

a) in colder winters;

in colder winters and more rainfall

1) Match:

Part of the border

a) west

b) east.

natural frontier

Ural mountains;

Kazakh small hills;

Yenisei.

The foundation of the West Siberian platform compared to the East European one:

a) younger

b) the same age;

c) more ancient.

The relief of Western Siberia is:

a) the predominance of hills;

b) alternation of uplands and lowlands;

c) the predominance of lowlands.

The thickness of the sedimentary rock cover on the West Siberian platform compared to the East European one:

a) less

b) the same;

c) more.

main reason strengthening the degree of climate continentality in Western Siberia compared to the Russian Plain is: a) the impact of the Arctic Ocean;

decreasing influence of the Atlantic; c) weakening of the western transference

6) Permafrost in Western Siberia compared to the Russian Plain has:

a) wider distribution;

b) less widespread.

In Western Siberia, there is the following range of natural zones:

a) from arctic deserts to forest-steppes;

b) from tundra to steppes;

c) from forest-tundra to semi-deserts.

The predominant soil type in Western Siberia:

a) tundra-gley;

b) podzolic;

c) sod-podzolic

6) The boundary of the distribution of permafrost in Western Siberia compared to East European plain shifted:

a) to the west

b) to the north;

c) south.

The distribution of natural zones on the territory of Western Siberia is a manifestation of:

a) latitudinal zonality;

b) altitudinal zonation.

Main types natural resources Western Siberia are:

a) oil and gas;

b) oil, gas and forest resources;

c) oil, gas, forest and soil resources

Tasks: to form knowledge about the features geographical location Eastern and North-Eastern Siberia as a factor determining the natural features of this territory; to develop the ability of students to independently establish the relationship of the geological structure with the relief and minerals; to systematize students' knowledge about the reasons for the formation of a sharply continental climate in Eastern and North-Eastern Siberia; to consolidate the ability to independently determine quantitative climatic indicators for various regions of Siberia and to acquaint them with the peculiarities of the climate; to study the features of the regime and nature of the flow of rivers and their connection with the relief and climate of Siberia.

1. Testing knowledge and skills on the topic "West Siberian Plain".

It is advisable to check the level of assimilation of knowledge and skills in a compacted form. Factual knowledge can be checked frontally in the form of a small test by options

Answers:

Option I - 1 - 1 c, 2a, 2 - c; 3 - a; 4 - b; 5 - a; 6 - a; 7 - b; 8 - c.

II option - 1 - 1a, 2c; 2 - a; 3 - in; 4 - in; 5 - b, c; 6 - in; 7 - a; 8 - b.

II. Getting new knowledge.

The study of this topic is complicated by the lack of study time. In preparing for the lessons, the teacher first of all selects the main thing, prepares tasks for students to work independently. The ways of organizing cognitive activity can be varied: solving cognitive problems, heuristic conversation, a seminar on the problems of rational use natural conditions and resources, game, competition of characteristics of individual geographical objects, crossword puzzles, small travel games.

The teacher distributes teaching time at his own discretion. Traditionally, in the first lesson, natural components are considered, in the second, natural complexes are studied.

When studying the nature of Central and North-Eastern Siberia, it is important to draw students' attention to understanding the features of nature, the manifestation of relationships, the characteristic features and integrity of landscapes. To do this, it is advisable to use a heuristic conversation with practical and independent work students with maps, textbook, visual aids.

1. Geographical position of a large natural area"Eastern and North-Eastern Siberia" students characterize independently, using the physical map of Russia and the map of large natural areas, placed in the atlas.

Questions and tasks:

1) What are the boundaries of Eastern and North-Eastern Siberia natural territory in the north, west, south and east.

2) Specify which landforms are part of Eastern and North-Eastern Siberia.

3) Describe the geographical location of this large natural area.

4) What is the peculiarity of its geographical position compared to the West Siberian Plain?

5) How does the Arctic Ocean affect the natural conditions of Eastern and North-Eastern Siberia?

6) How does the Atlantic Ocean affect the natural conditions of this part of Siberia?

7) Explain why the Pacific Ocean, relatively close to Eastern Siberia, has practically no effect on its natural conditions.

8) Make a generalizing conclusion about how the geographical location of Eastern and North-Eastern Siberia affects the natural conditions of the territory.

Summarizing the students' answers, the teacher talks about the size of this natural area and the reasons for close attention to the study of the natural conditions and resources of the Eastern and Northeast Siberia at present.

1) According to the tectonic map, establish on which geological structures East and North-Eastern Siberia is located.

2) What landforms are located in this area?

3) What is the peculiarity of the surface structure?

When characterizing the relief, students pay attention to the fact that the territory of the region is much higher than neighboring Western Siberia. Elevations rise to 500 m, plateaus - up to 1000 m, highlands - up to 1500 - 2000 m. The highest point is Pobeda peak in the ridge. Chersky with a height of 3147 m. Thus, a conclusion is formed about the diversity of the relief of Eastern and North-Eastern Siberia.

When analyzing a tectonic map, students are convinced that the Siberian Platform lies at the base of the Central Siberian Plateau. How to explain the structure of the surface and the differences in the relief on the plateau? If the students have difficulties, the teacher himself answers this question.

Teacher. The reason for the differences in the relief on the Central Siberian Plateau lies in the unevenness of the foundation of the platform. Where the foundation comes to the surface, the Anabar Plateau was formed. Separate blocks of the foundation are omitted, in the relief this is expressed by the lowlands - the North Siberian and Central Yakut. A feature of the relief of the region is the presence of volcanic plateaus. In the Mesozoic, a huge amount of lava poured out through cracks in the platform, which, solidifying, formed continuous covers. A lot of lava solidified among sedimentary rocks. Subsequently, loose rocks were destroyed, and igneous ones remained, forming a stepped relief - traps. Another feature of the relief is the abundance of kurums. They are formed as a result of intense frost weathering.

4) From the maps, determine which minerals are mined on the Central Siberian Plateau. Explain why minerals of both sedimentary and igneous origin are mined on the plateau.

5) What minerals are the mountains of Mesozoic folding rich in and explain why there are a lot of various minerals in these mountains?

The teacher only explains that deposits of ore minerals are associated with traps, and iron ore and diamonds are associated with kimberlite pipes.

Teacher. Interestingly, the discovery of diamonds on the territory of the Siberian platform is an example of a brilliant confirmation of a scientific forecast. Such a forecast was made by V.S. Sobolev in 1937 based on a comparison of the geology of the Siberian and African platforms. The search for diamonds began in 1940, and in 1947 the first diamonds were found in placers, and in 1954 the first kimberlite pipes were found. A feature of the development of the mountains of North-Eastern Siberia is the formation of placer gold deposits. Placers are located in terraces, valleys and riverbeds. They were formed due to the erosion of granitic igneous rocks. Gold is a common companion of deposits of tin, cobalt, arsenic and other ores.

3. The climatic features of Eastern and North-Eastern Siberia are studied using atlas maps. It is important that schoolchildren independently work out the factual material characterizing the features of the climate, and, relying on it, draw generalizing conclusions about the typical features of the climate of this territory. The teacher organizes the work using the following tasks:

1) For the cities of Norilsk, Irkutsk and Oymyakon, determine the average temperatures in July, January and the annual temperature range; calculate the maximum annual temperature amplitude; calculate the moisture coefficient; identify the types of air masses.

2) Based on the obtained climatic data, draw a conclusion about the typical features of the climate of Eastern and North-Eastern Siberia.

Students write down in a notebook the main features of a sharply continental climate:

large fluctuations in daily, monthly and annual temperatures;

low amount of precipitation;

great evaporation.

Oymyakon and Verkhoyansk are the cold poles of the northern hemisphere, where the average January temperature drops to -50 ° C, and the absolute minimum temperature is about -70 ° C.

3) Name the reasons that explain why on vast territory Eastern and North-Eastern Siberia, stretching from north to south for 2000 km and from west to east for more than 3000 km, has formed a sharply continental climate with very cold winters, the warmest summers and little precipitation compared to other regions of Russia in those same latitudes.

Complete the assignment in writing.

Climate-forming factors:

northern geographic location;

influence of the Arctic;

distance from the Atlantic Ocean;

significant absolute heights of the terrain;

strong cooling of the mainland in winter time, which contributes to the development of stable anticyclones.

4) Remember what kind of weather winter anticyclones are characterized by and what atmospheric processes are observed in them.

Teacher's explanations: The Siberian anticyclone is characterized by stable, very cold, clear, sunny, slightly cloudy, dry and calm weather in winter. The lowest air temperatures are observed in hinterland North-Eastern Siberia, in poorly ventilated intermountain basins, where cold air stagnates and cools down especially strongly. It is in such places that Verkhoyansk and Oymyakon are located. These intermontane basins are characterized by winter temperature inversions in the lower air layer. During inversions, an increase in air temperature with height by 2 degrees for every 100 m is observed. For this reason, it is less cold on the slopes of the mountains than in the basins, sometimes this difference is 15-20 °.

4. Describing permafrost, the teacher draws students' attention to cause-and-effect relationships in nature.

In one case, permafrost is a consequence of climatic conditions, a sharp continental climate. It is almost ubiquitous throughout the region. The thickness of the permafrost layer in many places exceeds hundreds of meters (600 m in the Vilyui basin). In summer, the upper horizon of the permafrost thaws in the north by 20-40 cm, and in the south - by several meters.

In another case, permafrost is the cause that determines the development of other components and natural phenomena. It causes swamping of the plains, has a great influence on the regime of inland waters, cools the soil and thus inhibits the soil-forming process. On permafrost, plants can grow only with a superficial root system, for example, larch.

5. In the final part of the lesson, in order to consolidate the students' skills to establish and characterize the connections of rivers with other components of nature, tasks of a partially search character are offered:

Explain why R. The Yenisei is the most abundant river in Russia, despite the fact that little precipitation falls in the basin.

Explain why there are many rapids and waterfalls on the Yenisei, Angara, Vilyui, but none on the Lena.

It is known that winters in Eastern Siberia are characterized by little snow, and in many places the snow is completely swept away. However, in spring, a high rise in water is observed on the rivers of Siberia, which reaches 10 m on the Lena, and even 20–25 m on the Lower Tunguska. Explain this natural phenomenon.

III. Summing up the lesson.

Homework: § 37, 38, put the nomenclature on the contour map.

a) The North-East of Russia is characterized by sharp orographic contrasts: medium-altitude mountain systems predominate, along with them there are plateaus, highlands and lowlands. North-Eastern Siberia is a predominantly mountainous country; lowlands occupy a little more than 20% of its area. The most important orographic elements - the marginal mountain systems of the Verkhoyansk Range and the Kolyma Highlands - form a 4000 km long arc convex to the south. Inside it are located the chains of the Chersky ridge, elongated parallel to the Verkhoyansk system, the ridges Tas-Khayakhtakh, Tas-Kystabyt (Sarycheva), Momsky, and others.

The mountains of the Verkhoyansk system are separated from the Chersky ridge by a lowered strip of the Yansky, Elginsky and Oymyakonsky plateaus. The Nera plateau and the Upper Kolyma highlands are located in the east, and in the southeast the Sette-Daban ridge and the Yudomo-Maysky highlands adjoin the Verkhoyansk ridge.

The highest mountains are located in the south of the country. Their average height is 1500-2000 m, however, in the Verkhoyansk, Tas-Kystabyt, Suntar-Khayat and Chersky ridges, many peaks rise above 2300-2800 m, and the highest of them - Mount Pobeda in the Ulakhan-Chistai ridge - reaches 3003 m.

In the northern half of the country, the mountain ranges are lower and many of them stretch in a direction close to meridional. Along with low ridges (Kharaulakhsky, Selennyakhsky), there are flat ridge-like uplands (Polousny Ridge, Ulakhan-Sis) and plateaus (Alazeysky, Yukagirsky). A wide strip of the coast of the Laptev Sea and the East Siberian Sea is occupied by the Yana-Indigirskaya lowland, from which, along the valleys of the Indigirka, Alazeya and Kolyma, the intermountain Sredneindigirskaya (Abyiskaya) and Kolyma lowlands protrude far to the south.

Thus, the North-East of Siberia is a huge amphitheater, inclined towards the Arctic Ocean;

b) The main plan of the modern relief of North-Eastern Siberia was determined by neotectonic movements. In the development of the relief of the Northeast after the Mesozoic mountain building, two periods are distinguished: the formation of widespread leveling surfaces (peneplains); and the development of intense newest tectonic processes that caused splits, deformation and displacement of ancient alignment surfaces, volcanism, violent erosion processes. At this time, the formation of the main types of morphostructures takes place: folded-block areas of ancient median massifs (Alazeya and Yukagagir plateaus, Suntar-Khayata, etc.); mountains revived by the latest arch-block uplifts and depressions of the rift zone (Moma-Selennyakh depression); folded mid-mountains of Mesozoic structures (mountains Verkhoyansk, Sette-Daban, Anyui, etc., the Yanskoye and Elga plateaus, the Oymyakon highlands); stratal-accumulative, sloping plains, created mainly by subsidence (Yano-Indigirskaya and Kolyma lowlands); fold-block ridges and plateaus on the sedimentary-volcanic complex (the Anadyr plateau, the Kolyma highlands, the ridges - Yudomsky, Dzhugdzhur, etc.);

c) The territory of the current North-Eastern Siberia in the Paleozoic and the first half of the Mesozoic was a site of the Verkhoyansk-Chukotka geosynclinal marine basin. This is evidenced by the large thickness of the Paleozoic and Mesozoic deposits, in some places reaching 20-22 thousand m, and the intense manifestation of tectonic movements that created the folded structures of the country in the second half of the Mesozoic. Especially typical are the deposits of the so-called Verkhoyansk complex, whose thickness reaches 12-15 thousand m. It includes Permian, Triassic and Jurassic sandstones and shale, usually intensively dislocated and broken through by young intrusions.

The most ancient structural elements are the Kolyma and Omolon median massifs. Their base is composed of Precambrian and Paleozoic deposits, and the Jurassic suites covering them, unlike other areas, consist of weakly dislocated carbonate rocks, occurring almost horizontally; effusives also play a prominent role.

The remaining tectonic elements of the country are of younger age, predominantly Upper Jurassic (in the west) and Cretaceous (in the east). These include the Verkhoyansk folded zone and the Sette-Dabansky anticlinorium, the Yana and Indigirsko-Kolyma synclinal zones, as well as the Tas-Khayakhtakhsky and Momsky anticlinoria. The extreme northeastern regions are part of the Anyui-Chukotka anticline, which is separated from the median massifs by the Oloy tectonic depression filled with volcanic and terrigenous Jurassic deposits;

d) The main types of relief of North-Eastern Siberia form several distinct geomorphological tiers. The most important features of each of them are associated, first of all, with the hypsometric position, due to the nature and intensity of the latest tectonic movements. However, the location of the country in high latitudes and its harsh, sharply continental climate cause other than in more southern countries, altitudinal limits of the distribution of the corresponding types of mountainous relief. In addition, the processes of nivation, solifluction, and frost weathering are of greater importance in their formation. The forms of permafrost relief formation also play a significant role here, and fresh traces of Quaternary glaciation are characteristic even of plateaus and areas with low mountain relief.

In accordance with morphogenetic features, the following types of relief are distinguished within the country: accumulative plains, erosion-denudation plains, plateaus, low mountains, mid-mountain and high-mountain alpine relief.

Accumulative plains occupy areas of tectonic subsidence and accumulation of loose Quaternary deposits - alluvial, lacustrine, marine and glacial. They are characterized by slightly rugged topography and slight fluctuations in relative heights. Forms are widespread here, which owe their origin to permafrost processes, the large ice content of loose deposits and the presence of thick ground ice: thermokarst depressions, permafrost heaving mounds, frost cracks and polygons, and high ice cliffs intensively collapsing on sea coasts. Accumulative plains occupy vast areas of the Yana-Indigirskaya, Sredneindigirskaya and Kolyma lowlands, some islands of the seas of the Arctic Ocean (Faddeevsky, Lyakhovsky, Bunge Land, etc.). Small areas of them are also found in depressions in the mountainous part of the country (Momo-Selennyakhskaya and Seimchanskaya hollows, Yanskoye and Elga plateaus).

Erosion-denudation plains are located at the foot of some northern ridges (Anyuisky, Momsky, Kharaulakhsky, Kulara), on the peripheral sections of the Polousny ridge, the Ulakhan-Sis ridge, the Alazeysky and Yukagirsky plateaus, as well as on Kotelny Island. The height of their surface usually does not exceed 200 m, but near the slopes of some ridges it reaches 400-500 m. In contrast to the accumulative plains, these plains are composed of bedrock of various ages; the cover of loose sediments is usually thin. Therefore, rubble placers, sections of narrow valleys with rocky slopes, low hills prepared by denudation processes, as well as spots-medallions, solifluction terraces and other forms associated with the processes of permafrost relief formation are often found.

The plateau relief is most typically expressed in a wide strip separating the systems of the Verkhoyansk Range and the Chersky Range (Yanskoye, Elginskoye, Oymyakonskoye and Nerskoye plateaus). It is also characteristic of the Upper Kolyma Highlands, the Yukagir and Alazeya Plateaus, large areas of which are covered with Upper Mesozoic effusive rocks, which occur almost horizontally. However, most of the plateaus are composed of Mesozoic deposits folded into folds and represent denudation leveling surfaces, currently located at an altitude of 400 to 1200-1300 m. Upper Kolyma Highlands, where numerous granite batholiths appear in the form of high domed hills prepared by denudation. Many rivers in regions with a flat mountainous relief are mountainous in nature and flow in narrow rocky gorges.

The low mountains are occupied by areas subjected to uplifts of moderate amplitude (300-500 m) in the Quaternary. They are located mainly along the outskirts of high ridges and are dissected by a dense network of deep (up to 200-300 m) river valleys. The low mountains of North-Eastern Siberia are characterized by relief forms due to nival-solifluction and glacial processing, as well as an abundance of stony placers and rocky peaks.

The mid-mountain relief is especially characteristic of most massifs of the Verkhoyansk Range, the Yudomo-Maya Highlands, the Chersky Range, Tas-Khayakhtakh and Momsky. Significant areas are occupied by mid-mountain massifs also in the Kolyma Uplands and the Anyui Range. Modern medium-altitude mountains arose as a result of the latest uplifts of denudation plains of leveling surfaces, parts of which have been preserved here in places to this day. Then, in the Quaternary, the mountains were vigorously eroded by deep river valleys.

The height of the mid-mountain massifs is from 800-1000 to 2000-2200 m, and only at the bottom of deeply incised valleys the marks sometimes drop to 300-400 m. Relatively gentle relief forms prevail in the interfluve spaces, and fluctuations in relative heights usually do not exceed 200-300 m Forms created by Quaternary glaciers, as well as by permafrost and solifluction processes, are widespread everywhere. The development and preservation of these forms is facilitated by the harsh climate, since, unlike the more southern mountainous countries, many mid-mountain massifs of the Northeast are located above the upper limit of woody vegetation, in the mountain tundra. River valleys are quite diverse. Most often these are deep, sometimes canyon-like gorges (the depth of the Indigirka valley reaches, for example, 1500 m). However, the upper reaches of the valleys usually have a wide flat bottom and less high slopes.

The high-mountainous alpine relief is associated with areas of the most intense Quaternary uplifts, located at an altitude of more than 2000-2200 m. areas of the Verkhoyansk Range. Due to the fact that the most significant role in the formation of the Alpine relief was played by the activity of Quaternary and modern glaciers, it is characterized by deep dissection and large amplitudes of heights, the predominance of narrow rocky ridges, as well as cirques, cirques and other glacial landforms;

e) Among the minerals of this region, one can note numerous deposits of metals, in particular, tin, tungsten, gold, molybdenum, etc. These deposits are associated with Mesozoic-Cenozoic magmatism. Also in the region there are coal and brown coal basins (Zyryansky, Verkhoyansky).

Eastern Siberia is part of the Asian territory Russian Federation. Settled away from the borders Pacific Ocean to the Yenisei River. This zone is characterized by an extremely harsh climate and limited fauna and flora.

Geographic Description

Eastern and occupy almost two-thirds of the territory of Russia. They are located on the plateau. The eastern zone covers an area of about 7.2 million square meters. km. Its possessions extend up to the Sayan mountain ranges. Most of the territory is represented by the tundra lowland. The mountains of Transbaikalia play a significant role in the formation of the relief.

Despite the harsh climatic conditions, there are quite a lot of large cities in Eastern Siberia. The most attractive from an economic point of view are Norilsk, Irkutsk, Chita, Achinsk, Yakutsk, Ulan-Ude, and others. Within the zone are the Zabaikalsky and Krasnoyarsk Territories, the republics of Yakutia, Buryatia, Tuva and other administrative regions.

The main type of vegetation is the taiga. It will be washed from Mongolia to the borders of the forest-tundra. Occupies over 5 million sq. km. Most of the taiga is represented by coniferous forests, which make up 70% of the local vegetation. Soils develop unevenly relative to natural zones. In the taiga zone, the soil is favorable, stable, in the tundra - rocky, frozen.

Within the interfluve and lowlands, insignificant swamps are observed. However, they are much less than in the same Western Siberia. But in the eastern region, arctic deserts and deciduous plantations are often found.

Terrain characteristics

Eastern Siberia of Russia is located at a high level above the sea. All the fault of the plateau, which is located in the middle part of the zone. Here the height of the platform varies from 500 to 700 meters above sea level. The relative averageness of the region is noted. The highest points are the interfluve of the Lena and the Vilyui plateau - up to 1700 meters.

The base of the Siberian platform is represented by a crystalline folded basement, on which there are huge sedimentary layers up to 12 kilometers thick. The north of the zone is determined by the Aldan shield and the Anabar massif. The average thickness of the soil is about 30 kilometers.

To date, the Siberian platform contains several main types of rocks. These are marble, and schist, and charnockite, etc. The oldest deposits date back to 4 billion years. Igneous rocks were formed as a result of eruptions. Most of these deposits are located in and also in the Tunguska depression.

The modern relief is a combination of lowlands and uplands. Rivers flow in the valleys, swamps form, coniferous trees grow better on the hills.

Features of the water area

It is generally accepted that the Far East faces the Arctic Ocean with its "facade". Eastern region borders on such seas as the Kara, Siberian and Laptev. Of the largest lakes, it is worth highlighting Baikal, Lama, Taimyr, Pyasino and Khantayskoye.

Rivers flow in deep valleys. The most significant of them are the Yenisei, Vilyui, Lena, Angara, Selenga, Kolyma, Olekma, Indigirka, Aldan, Lower Tunguska, Vitim, Yana and Khatanga. The total length of the rivers is about 1 million km. Most of the inland basin of the region belongs to the Arctic Ocean. Other external water areas include such rivers as Ingoda, Argun, Shilka and Onon.

The main source of nutrition for the inner basin of Eastern Siberia is the snow cover, which melts in large volumes under the influence of sunlight from the beginning of summer. The next most important role in the formation of the continental water area is played by rains and groundwater. The highest level of the basin's runoff is observed in the summer.

The largest and most important river in the region is the Kolyma. Its water area occupies more than 640 thousand square meters. km. The length is about 2.1 thousand km. The river originates in the Upper Kolyma Highlands. Water consumption exceeds 120 cubic meters per year. km.

Eastern Siberia: climate

The formation of meteorological features of the region is determined by its territorial location. The climate of Eastern Siberia can be briefly described as continental, consistently severe. There are significant seasonal fluctuations in cloudiness, temperature, and precipitation levels. The Asian anticyclone forms vast areas of high pressure in the region, especially this phenomenon occurs in winter. On the other hand, severe frost makes air circulation changeable. Because of this, temperature fluctuations at different times of the day are more significant than in the west.

The climate of North-Eastern Siberia is represented by changeable air masses. It is characterized by increased precipitation and dense snow cover. This area is dominated by continental flows, which are rapidly cooling in the ground layer. That is why in January the temperature drops to a minimum. Arctic winds prevail at this time of the year. Often in winter, you can observe air temperatures down to -60 degrees. Basically, such minima are inherent in depressions and valleys. On the plateau, the indicators do not drop below -38 degrees.

Warming is observed with the arrival of air flows from China and Central Asia to the region.

winter time

No wonder it is believed that Eastern Siberia has the heaviest and most severe. The table of temperature indicators in winter is proof of this (see below). These indicators are presented as average values for the last 5 years.

Due to the increased dryness of the air, the constancy of the weather and the abundance of sunny days, such low rates are easier to tolerate than in a humid climate. One of the defining meteorological characteristics of winter in Eastern Siberia is the absence of wind. Most of the season there is a moderate calm, so there are practically no blizzards and snowstorms here.

Interestingly, in the middle part of Russia, a frost of -15 degrees is felt much stronger than in Siberia -35 C. Nevertheless, such low temperatures significantly worsen the living conditions and activities of local residents. All living quarters have thickened walls. Expensive fuel boilers are used to heat buildings. The weather begins to improve only with the onset of March.

warm seasons

In fact, spring in this region is short, as it comes late. The eastern one, which changes only with the arrival of warm Asian air currents, begins to wake up only by mid-April. It is then that the stability of positive temperatures during the daytime is noted. Warming comes in March, but it is insignificant. By the end of April, the weather begins to change in better side. In May, the snow cover completely melts, the vegetation blooms.

In summer, the weather becomes relatively hot in the south of the region. This is especially true for the steppe zone of Tuva, Khakassia and Transbaikalia. In July, the temperature here rises to +25 degrees. The highest rates are observed on flat terrain. It is still cool in the valleys and highlands. If we take the whole of Eastern Siberia, then the average summer temperature here is from +12 to +18 degrees.

Climate features in autumn

Already at the end of August, the first frosts begin to envelop the Far East. They are observed mainly in the northern part of the region at night. Shines during the day bright sun, there are rains with sleet, sometimes wind intensification. It is worth noting that the transition to winter is much faster than from spring to summer. In the taiga, this period takes about 50 days, and in the steppe area - up to 2.5 months. All these are characteristic features that distinguish Eastern Siberia from other northern zones.

The climate in autumn is also represented by an abundance of rains coming from the west. Moist Pacific winds blow most often from the east.

Precipitation level

Relief is responsible for atmospheric circulation in Eastern Siberia. Both the pressure and the speed of air mass flows depend on it. About 700 mm of precipitation falls annually in the region. The maximum indicator for the reporting period is 1000 mm, the minimum is 130 mm. The level of precipitation is not clearly defined.

On the plateau in the middle lane, it rains more often. Due to this, the amount of precipitation sometimes exceeds the mark of 1000 mm. The most arid region is Yakutsk. Here the amount of precipitation varies within 200 mm. The least rain falls between February and March - up to 20 mm. The optimal zones for vegetation in relation to precipitation are considered western areas Transbaikalia.

Permafrost

Today there is no place in the world that could compete in terms of continentality and meteorological anomalies with a region called Eastern Siberia. The climate in some areas is striking in its severity. In the immediate vicinity of the Arctic Circle lies the permafrost zone.

This area is characterized by low snow cover and low temperatures throughout the year. Because of this, mountain weather and the ground lose a huge amount of heat, freezing to whole meters in depth. The soils here are predominantly stony. Groundwater is underdeveloped and often freezes for decades.

Vegetation of the region

The nature of Eastern Siberia is mostly represented by taiga. Such vegetation extends for hundreds of kilometers from the Lena River to the Kolyma. In the south, the taiga borders on the local possessions are untouched by man. However, due to the arid climate, the threat of large-scale fires always hangs over them. In winter, the temperature in the taiga drops to -40 degrees, but in summer the figures often rise to +20. Rainfall is moderate.

Also, the nature of Eastern Siberia is represented by the tundra zone. This zone is adjacent to the Arctic Ocean. The soils here are bare, the temperature is low, and the humidity is excessive. Flowers such as cotton grass, gravel, poppy, saxifrage grow in mountainous areas. From the trees of the region, one can distinguish spruces, willows, poplars, birches, pines.

Animal world

Almost all regions of Eastern Siberia are not rich in fauna. The reasons for this are permafrost, lack of food and underdevelopment of deciduous flora.

The largest animals are the brown bear, lynx, elk and wolverine. Sometimes you can meet foxes, ferrets, stoats, badgers and weasels. Musk deer, sable, deer and bighorn sheep live in the central strip.

Because of the eternally frozen soil, only a few species of rodents are found here: squirrels, chipmunks, flying squirrels, beavers, marmots, etc. But the feathered world is extremely diverse: capercaillie, crossbill, hazel grouse, goose, crow, woodpecker, duck, nutcracker, sandpiper, etc. .

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federal state budgetary educational institution higher vocational education"National Mineral and Raw Materials University "Gorny"

Faculty of secondary vocational education

(College of Geodesy and Cartography)

TEST

by geography

Option number 8

Completed:

1st year student of PG-15z group

FULL NAME. Konyaev Artur Georgievich

Lecturer: Dashicheva A.V.

St. Petersburg-2015

TASK 1: Biogenic landforms. Relief-forming activity of animals and plants.

TASK 2: North-Eastern Siberia of Russia, physical and geographical characteristics

Relief is a collection of forms earth's surface, different in shape, size, origin, age and history of development. The relief influences the formation of the climate, the nature and direction of the flow of rivers depend on it, the features of the distribution of flora and fauna are associated with it. Relief significantly affects life and economic activity person.

The significance of organisms in the life of the Earth is great and varied. The processes of changing the surface of the Earth as a result of the activity of living organisms are called biogeomorphological, and the relief created with the participation of plants and animals is called biogenic. These are mainly nano-, micro- and mesoforms of relief.

A grandiose process, carried out largely due to organisms, is the formation of sediments (for example, limestones, caustobioliths and other rocks).

Plants and animals are also involved in a complex universal process - the weathering of rocks, both as a result of direct impact on rocks, and due to their metabolic products. Not without reason, sometimes, along with physical and chemical weathering, biological weathering is distinguished.

Plants and animals have a significant impact on various natural processes, such as erosion. The destruction of vegetation on steep slopes, the trampling of plants by animals (the so-called "slaughter trails"), the loosening of soils by burrowing animals - all this increases erosion. This is especially dangerous on the mountain slopes, where distant pasture cattle breeding is carried out. There, due to excessive pasture load, various large-scale slope processes often come to life, the results of which are felt even in the foothills. Grassing of slopes (sowing meadow perennial long-rhizome grasses) holds soil together and reduces erosion.

Abundant aquatic vegetation in the rivers, as well as the inhabitants of water bodies, influence the channel processes. Beaver dams change the hydrological regime of rivers and geomorphological processes in the riverbed. Due to the damming of the rivers, swampy, hummocky floodplains are formed in the areas above the beaver dams.

Vegetation contributes to the overgrowth of lakes, filling them organic mass. As a result, leveled hummocky surfaces of marshes appear on the site of lake basins. In the tundra, peat mounds are very characteristic.

Plants and animals are actively involved in the creation of some types of accumulative shores. In the equatorial-tropical latitudes, mangrove shores are formed, growing towards the sea due to the death of the plant mass. In temperate latitudes, along the shores of seas and lakes, reed shores similar to them appear.

On the coasts of the seas, shell beaches are created from animal shells with the participation of wave activity. Such accumulative landforms as coral structures are also widely known: coastal, barrier (for example, the Great Barrier Reef off the coast of Australia), ring atolls, which are numerous in the Pacific and Indian Oceans.

Burrowing animals also contribute to the formation of a biogenic relief. As a result of earth emissions, they create molehills, marmots, bobbins - mounds up to a meter high. Termite hills reach up to 4-5 m in height with a diameter of 15-20 m and create a kind of small-hilly relief in the Australian and African savannahs.

Animals and plants perform destructive work, which is often much more diverse and complex than the similar activity of various agents of inanimate nature (wind, water, etc.).

The accumulative activity of animals and plants causes a wide variety of positive landforms. You can, for example, point to marmot bumps, which are ejections of soil from holes. However, the largest positive landforms are formed due to the accumulation of plant residues in the form of peat. Ridges composed of peat are often found on the surface of raised bogs. Together with the depressions separating them (hollows), they create a kind of ridge-hollow surface of the marshes. The height of the ridges above the surface of the hollows ranges from 15 to 30 cm and rarely reaches 50-70 cm.

As a result of the vital activity of animals and plants, various forms of relief arise, which can be divided into the following main groups:

landforms due to their destructive activity;

landforms due to their accumulative activity.

Seven-Eastern Siberia is located in the extreme northeast of Eurasia at the junction of three lithospheric plates - Eurasian, North American and Pacific, which determined the extremely complex relief of the territory. In addition, over the course of a long geological history, cardinal rearrangements of tecto- and morphogenesis have repeatedly occurred here.

If we accept that the territory of North-Eastern Siberia corresponds to the Late Mesozoic Verkhoyansk-Chukotka fold-cover region, then its boundaries are: in the west - the Lena valley and the lower reaches of the Aldan, from where, crossing the Dzhugdzhur, the border goes to Sea of Okhotsk; in the southeast, the border runs along the lowland from the mouth of the Anadyr to the mouth of the Penzhina; in the north - the seas of the Arctic Ocean; in the south and east - the seas of the Pacific Ocean. Some geographers do not include the Pacific coast in North-Eastern Siberia, drawing the boundary along the watershed of the rivers of the basins of the Arctic and Pacific Oceans.

In the Precambrian and Paleozoic, median massifs appeared in this area in the form of individual microcontinents (Kolyma-Omolon and others), which during the Mesozoic folding were woven into the lace of folded mountains. At the end of the Mesozoic, the territory experienced peneplanization. At that time, there was an even warm climate with coniferous-broad-leaved forests, and North American flora penetrated here by land on the site of the Bering Strait. During the Alpine folding, the Mesozoic structures were split into separate blocks, some of which rose and others sank. The median massifs rose entirely, and where they split, lava came out. At the same time, the shelf of the Arctic Ocean sank and the relief of North-Eastern Siberia acquired the appearance of an amphitheater. Its highest steps run along the western, southern, and eastern borders of the territory (Verkhoyansk Range, Suntar-Khayata, and the Kolyma Highlands). A step below are numerous plateaus on the site of the median massifs (Yanskoye, Elginskoye, Yukagirskoye, etc.) and the Chersky Range with the highest point of North-Eastern Siberia - Mount Pobeda (3003 m). The lowest step is the marshy Yano-Indigirskaya and Kolyma lowlands.

Arctic desert zone.

Tundra zone.

Taiga zone.

The Arctic Desert is part of the Arctic geographic zone, the Arctic Ocean basin. This is the northernmost of the natural zones, characterized by an arctic climate. The spaces are covered with glaciers, rubble and stone fragments.

It has low air temperatures in winter up to? 60 ° C, on average - 30 ° C in January and +3 ° C in July. It is formed not only due to the low temperatures of high latitudes, but also due to the reflection of heat (albedo) in the daytime from the snow and under the ice crust. The annual amount of atmospheric precipitation is up to 400 mm. In winter, the soil is saturated with layers of snow and barely thawed ice, the level of which is 75-300 mm. [Source not specified 76 days]

The climate in the Arctic is very harsh. Ice and snow cover lasts almost the whole year. In winter, there is a long polar night (at 75 ° N - 98 days; at 80 ° N - 127 days; in the region of the pole - half a year). This is a very harsh time of the year. The temperature drops to −40 °C and below, strong gale-force winds blow, snowstorms are frequent. In summer, there is round-the-clock lighting, but there is little heat, the soil does not have time to completely thaw. The air temperature is slightly above 0 °C. The sky is often overcast with gray clouds, it rains (often with snow), due to the strong evaporation of water from the surface of the ocean, thick fogs form.

Flora and fauna

The Arctic desert is practically devoid of vegetation: there are no shrubs, lichens and mosses do not form a continuous cover. The soils are thin, with patchy (island) distribution mainly only under vegetation, which consists mainly of sedges, some grasses, lichens and mosses. Extremely slow recovery of vegetation. The fauna is predominantly marine: walrus, seal, in summer there are bird colonies. Terrestrial fauna is poor: arctic fox, polar bear, lemming.

Tumndra is a type of natural areas lying beyond the northern limits of forest vegetation, spaces with permafrost soil that is not flooded by sea or river waters. The tundra is located north of the taiga zone. By the nature of the surface of the tundra are swampy, peaty, rocky. The southern border of the tundra is taken as the beginning of the Arctic. From the north, the tundra is limited by the zone of arctic deserts. Sometimes the term "tundra" is applied to similar natural areas of Antarctica.

Tundra in Alaska in July

The tundra is characterized by a very harsh climate (the climate is subarctic), only those plants and animals that can endure cold and strong winds live here. In the tundra, large fauna is quite rare.

Winter in the tundra is extremely long. Since most of the tundra is located beyond the Arctic Circle, the tundra experiences a polar night in winter. The severity of winter depends on the continentality of the climate.

The tundra, as a rule, is deprived of climatic summer (or it comes for a very short time). The average temperature of the warmest month (July or August) in the tundra is 5-10 °C. With the advent of summer, all vegetation comes to life, as the polar day comes (or white nights in those areas of the tundra where the polar day does not occur).

May and September are the spring and autumn of the tundra. It is in May that the snow cover melts, and already in early October it usually sets again.

In winter, the average temperature is up to? 30 ° C

There can be 8-9 winter months in the tundra.

Animal and plant world

The vegetation of the tundra is primarily lichens and mosses; the angiosperms encountered are low grasses (especially from the Grass family), shrubs and shrubs (for example, some dwarf species of birch and willow, berry bushes, princess, blueberry).

Typical inhabitants of the Russian tundra are reindeer, foxes, bighorn sheep, wolves, lemmings and hare. There are few birds: Lapland plantain, white-winged plover, red-throated pipit, plover, snow bunting, snowy owl and ptarmigan.

Rivers and lakes are rich in fish (nelma, broad whitefish, omul, vendace and others).

The swampiness of the tundra allows the development of a large number of blood-sucking insects that are active in the summer. Due to the cold summer, there are practically no reptiles in the tundra: low temperatures limit the ability of cold-blooded animals to live.

Taigam is a biome characterized by the predominance of coniferous forests (boreal species of spruce, fir, larch, pine, including cedar).

Pinezhsky forest.

The taiga is characterized by the absence or weak development of undergrowth (since there is little light in the forest), as well as the monotony of the grass-shrub layer and moss cover (green mosses). Shrub species (juniper, honeysuckle, currant, etc.), dwarf shrubs (blueberries, lingonberries, etc.) and herbs (oxalis, wintergreen) are not numerous both in Eurasia and in North America.

In the north of Europe (Finland, Sweden, Norway, Russia) spruce forests predominate, in North America (Canada) - spruce forests with an admixture of Canadian larch. The taiga of the Urals is characterized by light coniferous forests of Scots pine. in Siberia and Far East sparse larch taiga dominates with an undergrowth of elfin cedar, Daurian rhododendron, and more.

The fauna of the taiga is richer and more diverse than that of the tundra. Numerous and widespread: lynx, wolverine, chipmunk, sable, squirrel, etc. Of the ungulates, there are reindeer and red deer, elk, roe deer; hares, shrews, rodents are numerous: mice, voles, squirrels and flying squirrels. Of the birds are common: capercaillie, common hazel grouse, nutcracker, crossbills, etc. For the taiga North America American species of the same genera are typical as in Eurasia.

In the taiga forest, in comparison with the forest-tundra, the conditions for the life of animals are more favorable. There are more settled animals here. Nowhere in the world, except for the taiga, there are so many fur-bearing animals.

In winter, the vast majority of invertebrate species, all amphibians and reptiles, as well as some mammalian species, plunge into suspended animation and hibernation, and the activity of a number of other animals decreases.

Taiga types

According to the species composition, light coniferous (Scots pine, some American species of pine, Siberian and Dahurian larch) and more characteristic and widespread dark coniferous taiga (spruce, fir, stone pine, Korean cedar) are distinguished. Tree species can form pure (spruce, larch) and mixed (spruce-fir) forest stands.

The soil is usually sod-podzolic. Humidity is sufficient. 1-6% humus.

Evaporation 545 mm, precipitation 550 mm, average temperature in July 17°-20 °C, in winter the average temperature in January in the west? 6 °C, and in the east? 13 °C

A sharply continental climate operates on the territory of North-Eastern Siberia. Almost all of North-Eastern Siberia lies within the Arctic and subarctic climatic zones. The temperature is on average below? 10 °.

North-Eastern Siberia can be divided into 3 climatic zones.

Hydrography

Northeastern Siberia is dissected by a network of many rivers flowing to the Laptev and East Siberian seas. The largest on them - Yana, Indigirka and Kolyma - flow almost in a meridional direction from south to north. Cutting through mountain ranges in narrow deep valleys and receiving numerous tributaries here, they, already in the form of high-water streams, go to the northern lowlands, where they acquire the character of flat rivers.

Most rivers are fed mainly by the melting of snow cover in early summer and summer rains. Groundwater, melting of snow and glaciers in high mountains, as well as icings, play a certain role in feeding the rivers. More than 70% of the annual river flow falls on three calendar summer months.

The largest river in North-Eastern Siberia - Kolyma (basin area - 643 thousand km2, length - 2129 km) - begins in the Upper Kolyma Highlands. Somewhat below the mouth of the Korkodon River, the Kolyma enters the Kolyma Lowland; its valley widens sharply here, the fall and speed of the current decrease, and the river gradually acquires a flat appearance. Near Nizhnekolymsk, the width of the river reaches 2-3 km, and the average annual discharge is 3900 m3/sec (flow of about 123 km3 of water).

Origins of the second major river- Indigirka (length - 1980 km, basin area - 360 thousand km2) - located in the Oymyakon Plateau. Crossing the Chersky Range, it flows in a deep and narrow valley with almost steep slopes; rapids are often found here in the channel of the Indigirka. Then the river enters the plain of the Sredneindigirskaya lowland, where it breaks into branches separated by sandy islands. Below the village of Chokurdakh, the delta begins, with an area of 7700 km2. Indigirka has a runoff of more than 57 km3 per year (an average annual flow is 1800 m3/sec).

The western regions of the country are drained by Yana (length - 1490 km2, basin area - 238 thousand km2). Its sources - the Dulgalakh and Sartang rivers - flow down from the northern slope of the Verkhoyansk Range. After their confluence within the Yan Plateau, the river flows in a wide valley with well-developed terraces. In the middle part of the current, where the Yana crosses the spurs of the mountain ranges, its valley narrows, and rapids appear in the channel. The lower reaches of the Yana are located on the territory of the coastal lowland; when it flows into the Laptev Sea, the river forms a large delta (about 5200 km2 in area).

Yana is characterized by long summer floods, which is due to the gradual melting of snow cover in the mountainous regions of its basin and the abundance of summer rains. Most high levels waters are observed in July and August. The average annual discharge is 1000 m3/s, and the runoff per year is over 31 km3.

Most of the lakes of North-Eastern Siberia are located on the northern plains, in the basins of the Indigirka and Alazeya. Here there are places where the area of the lakes is not less than the area of the land separating them. The abundance of lakes, of which there are several tens of thousands, is due to the small ruggedness of the lowland relief, difficult runoff conditions, and the widespread permafrost. Most often, lakes occupy thermokarst basins or depressions in floodplains and on river islands. All of them are distinguished by their small size, flat banks, shallow depths (up to 4-7 m). For seven to eight months, the lakes are bound by a powerful ice cover; very many of them freeze to the bottom in the middle of winter.

On the territory of North-Eastern Siberia there is: gold, tin, polymetals, tungsten, mercury, molybdenum, antimony, cobalt, arsenic, coal.

Unlike other parts of Siberia, the amount of high-quality timber here is relatively small.

relief siberia russia

Literature

1. Lyubushkina S.G. General geography: Proc. allowance for university students enrolled in special. "Geography" / S.G. Lyubushkina, K.V. pashkang, A.V. Chernov; Ed. A.V. Chernov. - M. : Education, 2004. - 288 p.

2. N. A. Gvozdetsky and N. I. Mikhailov, Physical Geography of the USSR. Asian part. - 3rd ed., Rev. and additional Textbook for students geogr. fak. Univ. - M.: "Thought", 1978. 512 p.

3. Davydova M.I., Rakovskaya E.M. Physical geography of the USSR. - M.: Enlightenment, 1990.- 304 p.

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