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The maximum depth of Baikal is in km. Where is Lake Baikal located? Geography of Lake Baikal

Olkhon Island on Lake Baikal (Jason Rogers / flickr.com) Olkhon Island, Baikal (Jason Rogers / flickr.com) Olkhon Island (Jason Rogers / flickr.com) Jason Rogers / flickr.com Sergey Gabdurakhmanov / flickr.com Martin Lopatka / flickr .com Konstantin Malanchev / flickr.com Lake Baikal (Konstantin Malanchev / flickr.com) Sergey Gabdurakhmanov / flickr.com Khoboy Cape, Olkhon (Konstantin Malanchev / flickr.com) Konstantin Malanchev / flickr.com White Sturgeon (Heaven Ice Day / flickr.com) Heaven Ice Day / flickr.com LA638 / flickr.com

There are many places on earth that amaze with their beauty and uniqueness. Lake Baikal is one of them. This richest reservoir embodied all ideas about primevalness. It can be calm when there is calm on its surface, or it can be ferocious and cruel when a storm breaks out.

Asking the question of what attracts the attention of Baikal, it is quite simple to answer it. Features of the geographical characteristics of the giant reservoir attract tourists thousands of kilometers away.

Lake Baikal (Konstantin Malanchev / flickr.com)

The greatest depth of Baikal is impressive. The maximum depth of the lake is from the surface of the water at a distance of 1642 meters.

This indicator brings Baikal to a leading position among the lakes on the planet. Following the Russian Baikal, African Tanganyika is far behind. The difference between the maximum depths of these majestic reservoirs is about 160 meters.

The average depth over the entire area of ​​the lake also deserves attention. Most of Baikal has a depth of about 730 meters. As for the area of ​​this reservoir, here, for understanding, we can cite the area of ​​Belgium or Denmark as an example. Equating the size of the lake to the territory of one of these countries, one can only imagine its boundless expanses.

Olkhon Island (Jason Rogers / flickr.com)

The reason for the incredible depth and length of Lake Baikal is the countless number of rivers and streams flowing into it. There are more than 300 of them: large and small streams and full-flowing powerful river flows. Despite the fact that only the Angara takes its source from the lake.

It is worth noting that Lake Baikal is considered the world's largest natural reservoir of clean fresh water. Its volumes exceed even the famous American Great Lakes. If we add up the volumes of Michigan, Erie, Huron, Ontario and Lake Superior, then their sum will still not reach equality with the capacity of Baikal, which is over 23,600 cubic kilometers.

The huge depth, impressive expanses of the reservoir, the length and width of the mirror surface caused the inhabitants to often call Baikal the sea. Located in the southeast of Eurasia, a powerful lake is famous for its storms and tides (similar to sea ones).

Why is the lake called Baikal?

The history of the name of the lake is associated with several legends known to the local people. According to the first version, in translation from Turkic it means "rich lake", and in the original language it sounds like Bai-Kul.

Khoboy Cape, Olkhon (Konstantin Malanchev / flickr.com)

The second variant of the origin of the name, according to historians, is associated with the Mongols - in their language, the reservoir was called Baigal (rich fire) or Baigal dalai (big sea). There is also a third version of the name, according to which the neighboring Chinese called the lake the "North Sea". In Chinese, it sounds like Bei-Hai.

Lake Baikal is one of the oldest water bodies on the earth's surface. This orographic unit went through a rather complex and long process of formation in the earth's crust.

More than 25 million years ago, the reservoir began its formation, which continues to this day. Recent geological studies prove that Baikal can rightly be considered the beginning of another ocean, which, of course, will not appear in the near future, but scientists look at the fact that it will happen, almost unequivocally.

The shores of the lake are expanding significantly every year, the body of water is growing before our eyes, so in the place of the lake in a few million years, according to researchers, there will be an ocean.

Lake research

A unique distinguishing feature of the Baikal waters is their amazing transparency. At a depth of up to forty meters, you can easily see every pebble at the bottom.

Olkhon Island, Baikal (Jason Rogers / flickr.com)

This is explained by simple chemical laws. The fact is that almost all rivers flowing into Baikal pass through crystals of sparingly soluble rocks.

Hence the low level of Baikal mineralization. It is about 100 milligrams per liter of lake water.

Due to the maximum depth of Baikal and the high coastline, exceeding the surface of the ocean by 450 meters, the bottom of the reservoir is rightfully considered the deepest depression not only on this continent, but also among other continents.

Due to the fact that scientists found out the exact location of the maximum depth of the lake, a dive was made to this point several years ago.

It is located within the island of Olkhon. A modern deep-sea instrument sank to the bottom for more than 1 hour. For some time, scientists have filmed and taken samples for a detailed study of the bottom composition of the water and the rocks present.

During this experiment, the researchers managed to discover new microorganisms and identify the source of Baikal pollution with oil.

A story about Lake Baikal for children on the subject of the world will help prepare for the lesson.

Lake Baikal short message

Lake Baikal is the most mysterious and enigmatic. Tourists have admired its beauty for many years. 336 rivers and streams flow into the lake.

Depth of Lake Baikal an average of 730 m. The maximum depth of the lake is 1642 m. Even at a depth of 40 m, the bottom is perfectly visible.

Where is Lake Baikal located?

Baikal is located in the southern part of Eastern Siberia. The lake is located on the territory of the Republic of Buryatia, as well as the Irkutsk region.

How old is Baikal? It is difficult to give an exact number. Scientists traditionally determine the age of the lake at 25-35 million years.

Why is Baikal considered a unique natural phenomenon?

The main wealth of the lake is water, which makes up 90% of all fresh water reserves in Russia and 20% of global reserves. It is clean and transparent, and its oxygen saturation is 2 times higher than its content in ordinary reservoirs.
There are two reasons for this phenomenon:

  • The solubility of oxygen in water depends on its temperature. The lower the temperature, the more oxygen in the water. The water in Lake Baikal is very cold. At a depth of 100 m it is not more than 3-4 °C.
  • Algae also oxygenate the water.

Baikal water is also purified due to the activity of planktonic crustaceans. The crustaceans filter and absorb algae and bacteria cells. And clean water is returned to Baikal. Sponges, mollusks and worms contribute to water purification by eating various dying organisms.

Lake Baikal moderates the continental climate of these areas. Accumulating the heat received during the summer months, Baikal gives it back with the onset of winter cold.
Another inexplicable phenomenon is that the shores of the lake diverge at a rate of 1.5–2 cm per year.

Animals of Lake Baikal

More than 2600 species and subspecies of animals live in the lake, half of which live only in this reservoir. This lake is the only habitat for Baikal seals (seals).
The weight of Baikal seals can reach 130 kg and on land they become clumsy and defenseless.

In the waters of Baikal there are about 50 kinds of fish(omul, grayling, sturgeon, burbot).
Near Baikal live 200 bird species(ducks, herons, waders, representatives of the eagle family).

Problems of Baikal

In 1996, Baikal was included in the UNESCO World Heritage List. But human activities and tourists cause enormous damage to the environment. As a result, the swamping of the once crystal clear Baikal reservoir has taken on rampant proportions.

Besides:

  • pollute water by dumping waste from enterprises;
  • The Irkutsk hydroelectric power station, built on the main source of Baikal - the Angara, causes the lake to become shallow;
  • poaching leads to a decrease in the number of Baikal seals and omul, imperial eagles;
  • Predatory deforestation combined with forest fires are destroying this protected area.

Lake Baikal message for grade 4 you can write using this information.

Baikal has an elongated crescent shape. Its extreme points lie between 51°29" (Murino station) and 55°46" (the mouth of the Kichera River) north latitude and between 103°44" (Kultuk station) and 109°51" (Dagar Bay) east longitude.

The shortest line passing through the area of ​​the lake and connecting the most remote points of its shores, i.e. the length of the lake, equal to 636 km, the largest width of Baikal, equal to 79.4 km, is located between Ust-Barguzin and Onguren; the smallest, different 25 km, is located opposite the delta of the river. Selengi.

The area from which rivers currently collect water and bring it into Baikal, or its so-called catchment area, is 557,000 square meters. km *) . It is distributed in relation to the area of ​​the lake itself very unevenly (see the map of the basin). Along the entire western shore, the border of this area runs just a few kilometers from the lake shore. It is limited almost everywhere by the watershed of the mountains visible from the lake.

*) According to Yu.M. Shokalsky, the basin of Lake Baikal reaches 582,570 sq. km. - Approx. ed.

The basin of the Lena River approaches this watershed along the entire length of northern Baikal, and the Lena itself originates 7 km from the shore of Lake Baikal near Cape Pokoiniki. The catchment area of ​​Lake Baikal is most widespread to the south and southwest of the lake towards the Selenga river basin. The basin of this river, equal to 464,940 sq. km, is 83.4% of the total catchment area of ​​Lake Baikal. The next largest basin is the Barguzin River, whose basin is 20,025 sq. km and is 3.5% of the total catchment area of ​​Lake Baikal. The share of all other tributaries of Baikal accounts for a catchment area of ​​72,035 sq. km, equal to 13.1% of the total catchment area of ​​the lake.

Lake Baikal itself is located in a narrow basin, bordered by mountain ranges, spurs of the Sayan, cut in a number of places by relatively narrow valleys, along which its tributaries flow into the lake.

In the south, along its eastern shores, snow-covered peaks of the Khamar-Daban ridge stretch almost all year round with the highest heights up to 2000 m above sea level. This is exactly the chain of mountains that is visible to anyone traveling along the shores of Lake Baikal by rail. These mountains are especially clearly visible on the stretch between st. Baikal and st. Kultuk. The Pribaikalsky Range adjoins the western shores of southern Baikal. Its height almost along its entire length from Kultuk to the Small Sea does not exceed 1300-1200 m above sea level, but these mountains stand on the very shore of Lake Baikal.

Starting from the Small Sea and up to the northernmost tip of the western shores of Lake Baikal, the Baikal mountain range stretches, gradually rising to the north from Cape Rytoy to Cape Kotelnikovsky. In this area, Mount Karpinsky reaches its highest height of 2176 m, Mount Sinya - 2168 m, etc. Almost the entire length of the peaks of the Baikal Range is covered with snow that does not melt even in the middle of summer, and in many places traces of glaciers that descended from them until recently are visible.

This ridge is crossed by a series of deeply incised valleys along which mountain streams stretch. In terms of their picturesqueness, the eastern shores of the northern part of the lake are one of the most remarkable places on Baikal. To the eastern shores, starting from the Chivyrkuisky Bay and up to the northernmost tip of the lake, another ridge approaches - the Barguzinsky, reaching a considerable height - up to 2700 m. This ridge, however, is located at some distance from the shores, and relatively low foothills adjoin directly to the latter, in some places forming picturesque cliffs, and on the predominant part of the coast, gently descending to the waters of the lake.

The interval of the eastern shore of the lake between the Selenga and the Barguzin Bay is bordered by the Ulan-Burgasy ridge, which has a height of 1400-1500 m near Baikal.

The most pronounced bend of the coastline of Lake Baikal is the Svyatoy Nos peninsula, located between the two largest bays on Baikal - Barguzinsky and Chivyrkuisky.

This peninsula in the form of a massive block of stone, reaching a height of 1684 m, rises above Baikal, falling to the water with steep rocky cliffs. However, towards the mainland, it falls more gently and then passes into a narrow and swampy isthmus, merging with a vast lowland adjacent to the river valley. Barguzin. There is no doubt that until recently the Svyatoy Nos Peninsula was an island, and the waters of the Chivyrkuisky and Barguzinsky bays formed one vast strait, subsequently filled with drifts from the river. Barguzin.

Baikal has 19 permanent islands, the largest of them is Olkhon. It has a length of 71.7 km and an area of ​​729.4 sq. km. Olkhon Island, - separated from the continent by a strait less than a kilometer wide, called "Olkhon Gates", elongated in a northeasterly direction, is a mountain range, with the highest point - Mount Izhimey, reaching a height of 1300 m and abruptly breaking off to the east shore. The northern part of the island is wooded, while the southern part is completely devoid of tree vegetation and is covered with meadows with traces of steppe vegetation that was once, apparently, widespread here.

The shores of Olkhon facing the Small Sea are subjected to very strong destruction by the surf. Interesting both in its position and in its picturesqueness is the group of the Ushkany Islands, located opposite the Svyatoy Nos peninsula in the middle part of the lake. This group consists of four islands, of which Big Ushkany Island has an area of ​​9.41 sq. km, and the remaining three islands (Thin, Round and Long) do not exceed half a square kilometer. The large Ushkany Island reaches a height of 150 m, while the small ones are only a few meters above the average water level of Lake Baikal. All of them are rocky, with banks composed mainly of limestone and covered with dense forest. These islands are greatly destroyed and, as it were, cut off by the surf.

The time is not far off when the small Ushkany Islands will disappear under the surface of the waters of Lake Baikal.

The remaining islands on Baikal are all located near its shores, four of them are in the Chivyrkuisky Bay (Bol. and Small. Kyltygey, Elena and Baklany), six in the Small Sea (Khubyn, Zamugoy, Toinik, Ugungoy, Kharansa, Izokhoy, etc.) and the rest - in close proximity to the shores of other parts of Baikal, such as Listvenichny, Boguchansky, Baklany (near Peschanaya Bay), etc.

All islands have a total area of ​​742.22 sq. km, and most of them are large capes, separated from the continent under the influence of the destructive force of the surf. In addition, there are also several low sandy islands on Baikal, which in high water are completely hidden under water and protrude above the surface only when the water is low. Such are the islands elongated in the form of narrow strips that separate Proval Bay from Baikal (Chayachi Islands, Sakhalin), such are the islands that separate Angara Sor from open Baikal - the so-called Yarki. The islands separating the Istoksky Sor from the open Baikal belong to the same type.

The bays and inlets, which are so important for the anchorage of small vessels, are a relatively rare phenomenon on Baikal, moreover, they are very unevenly distributed along the coast.

The largest bays, Chivyrkuisky and Barguzinsky, which we have already mentioned above, are formed by the Svyatoy Nos peninsula protruding from the lake. Almost a bay is the so-called Small Sea, separated from open Baikal by Olkhon Island and Proval Bay, to the north of the Selenga Delta.

Peschanaya and Babushka bays on the western shore of southern Baikal are famous for their picturesqueness. Further, a peculiar group of bays, or rather lagoons, bearing the name “sors” on Baikal, are its former bays separated from the open lake by narrow sandy spits. Such are the Posolsky and Istoksky sors, separated from Baikal by narrow strips of land washed by the action of the surf, such is the Angarsky sor in the very north and Rangatui in the depths of the Chivyrkuisky Bay. All of them are separated from Baikal by narrow strips of sediment, in the form of sandy spits, sometimes hiding under the surface of the lake into high water.

Except for these large bays, almost separated from Baikal by its sediments, all other bends of its coast depend to a large extent on the direction of the coastline of Baikal, since the sinuosity of its coast depends on whether the coast is directed along or across the dominant direction of the mountain ranges. that make up the coast.

Those sections of the Baikal coast that are directed across the main direction of the mountain ranges that limit its basin are characterized by significant indentation, such as, for example, the Olkhon Gates or the southern coast of the Barguzin Bay. Those sections of the coast, which in their direction coincide with the direction of the mountain ranges that limit the Baikal basin in this area, are characterized, on the contrary, by exceptional straightness, disturbed only by secondary accumulations of coastal sediments or the eroding effect of the surf. This is the entire section of the western shore of Lake Baikal from the mouth of the river. Sarma to Cape Kotelnikovsky, such is the area that limits the Svyatoy Nos peninsula from the west, and many others.

In many areas, the shore of Lake Baikal is completely straight for many kilometers, and almost sheer cliffs, many meters high, break into the water very often. Particularly characteristic in this regard is the section between Sosnovka and the entrance to the Chivyrkuisky Bay on the eastern shore of middle Baikal or the section from Onguren to Cape Kocherikovsky on the western shore of middle Baikal.

According to the distribution of depths or the topography of the bottom, Baikal can be divided into three main deep depressions. The first of them - southern, occupies the entire southern Baikal to the confluence of the river. Selenga. The greatest depth of this depression is 1473 m, while the average depth is 810 m. The depression of southern Baikal is characterized by an exceptionally steep bottom slope near the western and southwestern shores and a relatively gentle slope near the opposite slopes.

Lacustrine deposits at the bottom of the southern depression have not completely smoothed out the features of the original relief, at the bottom of which there are a number of hollows and irregularities adjoining the Trans-Baikal coast and elongated in a northeasterly direction. These underwater ridges are especially pronounced in the part of the depression adjacent to the delta of the river. Selenga, and hide under its deposits. One of these ridges stands out so much that it forms in the middle of the width of Baikal on the line between the village. Goloustny and s. Posolsky shallow water, where depths of 94 m have been discovered, and the depths in this shallow water have not yet been sufficiently explored and it cannot be vouched for that even smaller depths will not be found there. This shallow water is, in all likelihood, a remnant of Stolbovoy Island, marked here on ancient maps, partly destroyed by the waters of Lake Baikal, partly submerged under its surface.

On the bridge separating the southern deep basin of Baikal from its middle basin, the depth does not exceed 428 m, and this bridge basically reflects the structure of the bedrock. This view is supported by the presence of a longitudinal ridge stretching in front of the Selenga delta, extending far both in the southwestern and northeastern directions and known by the locals as "manes". In its part adjacent to the Selenga, this lintel is gradually and significantly modified by the offsets of the Selenga.

To the east of the ridge directed to the northeast, approximately opposite the channel of the Selenga delta, called Kolpinnaya, there is a deepening of the bottom, reaching 400 m and locally called the "deep". A legend is connected with this abyss that in this place in the bottom of Baikal there is a hole through which Baikal connects either with Lake Kosogol or with the North Polar Sea. The emergence of this legend was facilitated by the fact that in the region of the depression there is a local whirlpool, which is well observed on quiet days, when all objects floating on the surface receive rotational motion. This whirlpool, which gives the impression that water is drawn into the hole below, is caused by the meeting of currents in two directions, which mix the surface layers of water to a depth of about 25 m.

The middle deep basin of Baikal occupies the entire space between the barrier against the Selenga and the line connecting the northern tip of Olkhon Island through the Ushkany Islands with Cape Valukan on the eastern shore of Lake Baikal. In this depression are the greatest depths of Baikal, reaching 1741 m. This depth is located at a distance of 10 km from Cape Ukhan on Olkhon. The average depth of the basin reaches 803 m. The area occupied by depths over 1500 m, which are not found in the other two deep basins of Baikal, is 2098 sq. km. km. The bottom has a particularly steep drop near the eastern shores of Olkhon Island, as well as to the east of the Ushkany Islands, where in some areas of the bottom the slope angle reaches over 80 °.

The bottom sections adjacent to the eastern coast of the depression are more gentle, and depths of 100 m in some places are here several kilometers from the coast.

The Barguzinsky Bay, which is part of the middle basin, has a very complex bottom topography. It is divided into two depressions by an underwater ridge. In the part of the bay adjacent to the southern head of the Svyatoi Nos peninsula, depths of more than 1300 m enter, which go far into its northern part. The relief of the bottom of the entire eastern part of the bay is influenced by the drifts of the river. Barguzin, which covered the bedrock topography with a thick layer of sediments.

The basin of middle Baikal is separated from the northern basin by an underwater ridge discovered by the station in 1932 and named Akademichesky.

This ridge, on which the depths do not exceed 400 m, stretches from the northern tip of Olkhon Island to the Ushkany Islands and further, less pronounced, to the north to Cape Valukan. Thus, the Ushkany Islands themselves are only the northern part of the Academic Ridge protruding above the surface. This ridge has slopes that descend very steeply to the southeast towards the depression of middle Baikal, and gently to the northwest towards the northern depression, i.e. retains the same features as the profiles of Olkhon Island and Bolshoi Ushkany Island.

The northern deep basin of Baikal occupies the entire space located north of the Akademichesky Range and includes the Small Sea. This depression has the greatest depth of only 988 m, its average depth is 564 m. The northern depression is characterized by an exceptional evenness of the bottom topography with a gradual increase in depth from the southern end of the Small Sea to the Kotelnikovsky Cape area. In the northern depression near the western shores, the bottom slopes more steeply into the depths than near the eastern shores, where there are significant shallow waters.

Most of the surface of the bottom of Lake Baikal at depths of more than 100 m is covered with thick deposits of silt, which mainly consists of countless shells, dead and fallen to the bottom of algae that lived in the upper layers of water. Only in a few places, like the Akademichesky Ridge, does the bottom of Baikal consist of bedrock, there are also areas of the bottom where rounded boulders and pebbles can be found at great depths, obviously, these are flooded channels of ancient rivers that are not covered with silt deposits due to the bottom currents there.

As for the shallow depths of Baikal, many consist of vast areas, especially those adjacent to river deltas, of sand or sand mixed with silt. Even closer to the coast, the bottom is covered mainly with stones and more or less large pebbles. Only in a few areas the bottom to the very shores is composed of sand. Such areas are of great importance, as they are convenient for seine fishing.

Not always, however, Baikal had those characteristic features of the bottom topography and the shape of its outlines that it currently possesses. There is reason to assert the opposite, namely, that Baikal in its present form was formed, from a geological point of view, relatively recently - at the end of the Tertiary or even at the beginning of the so-called Quaternary time. By this time, according to modern views of geologists, the formation of great depths of Baikal, as well as the formation of those mountain ranges that border the lake, belongs. There is little information about what the reservoir that was on the site of Baikal before that time was.

Apparently, it was a complex system of lakes, interconnected by straits and occupying a larger area than modern Baikal. There is reason to believe that this multi-lake area extended to Transbaikalia, Mongolia, and possibly Manchuria and Northern China.

Thus, Baikal in its current state is, to a certain extent, a remnant of water bodies that once occupied a vast area and repeatedly underwent significant changes. How this could affect the composition of the fauna and flora of Baikal, we will consider below, in the corresponding chapter.

During the ice age, when powerful glaciers covered large areas in some regions of Siberia, there was no continuous glaciation in the Baikal region, and glaciers descended to the shores of Baikal only in some places. Heaps of stones and sand, brought by glaciers and called moraines, in northern Baikal in many places descend from the adjacent mountains to Baikal itself, but it can be argued that this ice has never completely covered the surface of Baikal.

The moraines left after the ice age had a significant impact on the formation of the shores of Northern Baikal. Some capes in the north of Baikal are made of moraine materials, such as, for example, Cape Bolsodey. On the eastern shore of Northern Baikal, where many capes are also made of moraine material, they were subjected to severe destruction by the surf. Smaller boulders and loose material were washed away by the waves, and large boulders, preserved in the area as dangerous pitfalls for navigation, are the remains of moraines that were in these places and indicate their much greater distribution in the past than is the case now.

Geologists have made different assumptions about how the Baikal basin with its vast depths was formed in its modern form.

During the eighteenth and first half of the nineteenth centuries, geologists believed that Baikal was a deep sinkhole in the earth's crust, resulting from a major catastrophe that took place in this area of ​​​​the mainland. I.D. Chersky significantly changed these ideas. He considered Baikal not a failure, but a very ancient reservoir, preserved from the time of the Silurian Sea and gradually deepened due to the slow and smooth bowing of the earth's crust.

Later acad. V.A. Obruchev returned to the old ideas about the failure and explains the formation of the modern depths of Baikal by subsidence of the bottom of the graben, which this lake is. This subsidence occurred simultaneously with the uplift, which formed a mountainous country on the coast of Lake Baikal, and apparently continues to this day.

There are other geologists who also associate the formation of Baikal with the arched uplift of the Baikal region and subsidence - the collapse of the central part of this arch, but the time of this uplift, in their opinion, refers to the second half of the Quaternary period, i.e. to the time of the existence of primitive man.

Finally, according to the latest views of E.V. Pavlovsky, the Baikal depressions and the ridges separating them are the so-called synclines and anticlines, complicated by normal faults and developed gradually over many geological epochs, against the background of a general arched uplift of the Stanovoi ridge.

Finally, according to the views of N.V. Dumitrashko, Baikal is a complex system of three basins. The southern one arose during the Upper Jurassic, the middle one - in the Tertiary time, the northern one - at the border of the Tertiary and Quaternary time. The hollows and the ridges surrounding them are blocks into which the Baikal region was divided during the last epochs of mountain building. The slumped boulders turned into depressions, the rising ones turned into ridges. We have a number of evidence that the formation of the Baikal basin continues to this day, and that the bottom of the basin continues to sink, and its edges in the form of mountain ranges that limit the Baikal depressions rise.

Signs of the lowering of the coast, villages. Ust-Barguzin in 1932. Photo by G.Yu. Vereshchagin

The subsidence of the Baikal shores is especially pronounced in places where the basin continues beyond its shores, such as, for example, to the west of the area between Kultuk and Slyudyanka, in the Barguzin Bay, in the area between the Kichera and Upper Angara rivers, as well as on the far protruding basins of Baikal, the delta of the river. Selenga. In all these places, not only are the features of the coastline that indicate the gradual sinking of the coast under the lake level, but there are also historical facts confirming this. So the village of Ust-Barguzin has already changed its place twice, moving away from the shore of Lake Baikal, as the waters of the lake flood the place of its former location. This village is in a semi-flooded state at the present time. A similar phenomenon is observed in the village located at the mouth of the river. Kichery (Nizhnangarsk), where once was the center of the entire district, and now only a small number of houses remain. In the Selenga delta, the lowering of the terrain is expressed in the gradual swamping of the delta's meadows and the transformation into a swamp of once-dry mowings and even fields.

But the most significant is the lowering of part of the coast in the area of ​​the river. Selenga in December 1861, which led to the formation of Proval Bay. Then the northern part of the river delta disappeared under the waters of Lake Baikal. Selenga, the so-called Tsagan steppe with all the Buryat uluses, hayfields and other lands, with a total area of ​​​​about 190 square meters. km. This was preceded by an earthquake, while a strong vertical impact was felt, from which the soil on the steppe swelled with mounds and sand, clay and water were thrown out of the wide cracks formed. The steppe was flooded with water, which spouted fountains, more than two meters high. And the next day, the water of Baikal flooded the entire descended space to the Bortogoi steppe. According to eyewitnesses, the water came from the lake like a wall. In place of the steppe, Proval Bay is currently spreading with depths of up to three meters.

The secondary redistribution of sediments along the shores leads to a number of changes in the nature of the Baikal coastline, of which we will only point out the most important ones. Thus, the accumulation of these sediments in bays and other bends of the coast leads to their gradual straightening and the formation of shallow, gently descending to the water's edge banks, composed of sand or small pebbles, which are usually good non-aqueous tones.

The movement of sediment along the coast leads to other phenomena: for example, islands located near the coast are gradually attached to the coast by forming a bridge made of sediment connecting them to the coast. The largest of these bridges on Baikal connects, as already noted, the former rocky island of Svyatoy Nos with the continent, turning it into a peninsula. Typical dams made of sediments are observed on some capes of the Small Sea, such as Kurminsky, which was also once an island and only secondarily, by sediments, is attached to the coast. In the same way, some capes in the Chivyrkuisky Bay are attached to the coast, for example, Cape Monakhov, Cape Katun, etc.

The advancing coastal shaft near the mouth of the river. Yaksakan (east coast of northern Baikal). Photo by L.N. Tyulina

The movement of sediments along the coast also leads to the lacing of its bays from the lake. It is this process that caused the formation of its so-called sors on Baikal. Once it was just the bends of the coast - bays. Away from these bays along the coast, under the influence of the prevailing direction of the surf, the movement of sediments, which, having reached the bay, was deposited on its bottom in a direction that is a continuation of the general direction of the coast in this area. Thus, narrow, striped sandy islands arose, with which the sors are gradually separated from Baikal. In some cases, such bridges have already led to the almost complete separation of bays from the lake, such as, for example, Posolsky sor. In other cases, this process is not completed, such as, for example, the Istoksky sor, or it is just beginning, which takes place in Proval Bay.

In the cases prevailing on Lake Baikal, coastal sediments are weakly accumulated near its shores, and as a result, the shores themselves are exposed to the destructive action of the surf. Some parts of the coast are literally gnawed away by the surf. Up to a height of 5 meters or more, the rocks are destroyed, representing cliffs with an uneven, porous surface, and in many places niches and caves are carved into the rocks by the surf.

The destruction is especially strong on the shore of the island facing the Small Sea. Olkhon and, in particular, on the capes of this coast, as well as on the capes of the Olkhon Gate Strait.

The surf can also lead to the complete destruction of the islands, as if cutting them near the water's edge. It is in this state, very close to complete destruction, that the Small Ushkany Islands are located, of which the long island is currently only a few meters wide.

Completely cut off by the surf of Lake Baikal, apparently, is the island of Stolbovoy, which was once in the middle of Baikal between Goloustnoye and Posolsky and marked on old maps, and now its trace has been preserved only in the form of a shoal in this place.

The surf leads to the separation of capes from the continent and their transformation into islands. This is observed in the Small Sea, where the islands of Kharansa and Edor arose in this way.

Enormous waves that cause strong surf, as well as the roughness of the lake, in which this excitement is repeated very often, cause an exceptionally strong influence of the surf on the shores and leads both to their destruction and to the movement of sediments and the formation of shore sections washed by the lake. Baikal is a classic place for studying the work of the lake on its shores, which is far from being appreciated in this regard to the proper degree.

In southeastern Siberia, on the border between Buryatia and the Irkutsk region, there is the deepest freshwater lake in the world - Baikal.

Geography and hydrography

Has the shape of a crescent. Its length is about 630 km, width varies from 24 to 80 km. The surface area of ​​the lake is just over 31.7 thousand square kilometers, which is comparable to the area of ​​countries such as Denmark, Belgium or the Netherlands.
The lake is located in a giant bowl-hollow, surrounded in the west by rocky ridges, in the east by gently sloping hills. The maximum depth of the lake is 1642 m, the average is 745 m.
Baikal is the largest reservoir in the world in terms of fresh water reserves - 23.6 thousand km3. Also, this lake is the oldest on Earth. Its age, according to scientists, ranges from 25-30 million years. The most amazing thing is that the shores of the lake gradually diverge, expanding at a rate of 2 cm per year.
The lake is fed by about 350 rivers and streams (data have not been specified since the end of the 19th century), the largest of which are Upper Angara, Selenga, Barguzin, Sarma, Snezhnaya and Turka. Only 1 river flows out of Baikal - the Angara.
The lake is located in a seismically active zone.

Water, flora and fauna

Baikal water, despite the difficult ecological situation in the region, remains by far the cleanest in the world. It has very few dissolved minerals, organics and a lot of oxygen. In its composition, it is almost distilled. This is the only reservoir on the planet from which today you can drink water without purification and boiling.
The water is so transparent that in spring, when the vegetation of the lake has not yet awakened, the bottom is clearly visible, as if through glass, at a depth of 40 m.
The lake owes its purity to a microscopic crustacean - the Baikal epishura. The maximum size of 1 crustacean is no more than 1.5 mm; they are endemic, living exclusively in the waters of Lake Baikal. They are the most important component of the lake ecosystem. Up to 10 times a year, they pass the entire giant mass of lake water through themselves, filtering and purifying it.
The water temperature in the lake ranges from 0 to +20 degrees.
More than 2,600 species of plants and animals live in the lake itself, almost all of them are endemic, i.e. are not found anywhere else in the world - seal, omul, golomyanka, Baikal sturgeon, whitefish, grayling, yellowfly and others.
The coastal zone is also extremely rich in various representatives of flora and fauna - Siberian cedar, stilted trees, relic spruces, Barguzin sable, Olkhon vole, musk deer, Asiatic godwit and many other unique inhabitants.

Mysteries of Lake Baikal

The lake is a unique natural area in its characteristics. Not only Russian, but also American, European and Japanese scientists are at a loss when faced with unusual phenomena:
ice hills in the form of hollow cones, characteristic only for Lake Baikal,
migrating huge dark rings formed under the thickness of the ice,
mirages are an optical illusion, which has not yet been able to find a satisfactory explanation.

Most, most...

Baikal is the most
deep,
full-flowing,
old,
clean,
significant in terms of fresh water reserves
lake in the world.

Almost in the center of the huge continent of Eurasia is a narrow blue crescent - Lake Baikal. In the Baikal mountainous region, surrounded on all sides by high ridges, it stretches for 636 kilometers in length and up to 80 km in width. In terms of area, Baikal is equal to Belgium with its almost 10 million population, many cities and industrial centers, highways and railways.

AT Baikal 336 permanent rivers and streams flow into the lake, while half of the volume of water entering the lake comes from the Selenga. The only river that flows out of Baikal is the Angara.

The area of ​​the water surface of the lake is 31,470 square kilometers. The maximum depth reaches 1637 m, the average - 730 m.

In order to realize the immensity of the Baikal water body, imagine that the Angara, which annually takes out 60.9 km3 of water from the lake, would need 387 years of continuous work to drain its bowl. Provided, of course, that during this time not a liter of water gets into it and not a drop evaporates from its surface.

Undoubtedly, Baikal the deepest lake in the world. Not everyone knows that the world's second contender for this title, the African Lake Tanganyika, is behind the leader by as much as 200 meters. There are 30 islands on Baikal, the largest is Olkhon Island.

The question of the age of Baikal should be considered open. Usually, the literature gives a figure of 20-25 million years. However, the use of various methods for determining the age gives values ​​from 20-30 million to several tens of thousands of years. But, if we assume that the traditional point of view is correct, then Baikal can be considered the oldest lake on earth.

BAIKAL WATER

Baikal water unique and amazing, like Baikal itself. She is unusually
clear, pure and oxygenated. In not so ancient times, it was considered healing, with its help, diseases were treated.


In spring, the transparency of Baikal water is as much as 40 meters! This is explained by the fact that Baikal water, due to the activity of living organisms that live in it, is very
weakly mineralized and close to distilled.

The volume of water in Baikal reaches about 23 thousand cubic kilometers, which is 20% of the world and 90% of Russian fresh water reserves. There is more water in Baikal than in all five Great American Lakes combined - they only reached 22,725 km3 in total. Every year, the Baikal ecosystem reproduces about 60 cubic kilometers of clear, oxygenated water.

RESIDENTS OF BAIKAL

The exclusivity of many physical and geographical features of the lake was the reason
extraordinary diversity of its flora and fauna. And in this respect, it has no equal among the fresh waters of the world.

The lake is inhabited by 52 species of fish of several families:

  • sturgeons (Baikal sturgeon),
  • salmon (davatchan, taimen, lenok, Baikal omul - endemic fish, whitefish),
  • grayling (Siberian grayling),
  • pike,
  • carp,
  • loach,
  • catfish,
  • cod,
  • perch,
  • sculpins,
  • golomyanki.

The food pyramid of the lake ecosystem is crowned by a typical marine mammal - a seal,
or Baikal seal. The Baikal seal is the only representative of mammals in the lake. For almost the entire year
it lives in the water, and in autumn it forms mass haulouts on the rocky shores of the lake.


The life of many animals characteristic of Baikal is inextricably linked not only with the lake itself, but also with its coast. Seagulls, mergansers, goldeneyes, scoters, shelducks, white-tailed eagles, ospreys and many other bird species nest on the shores of the lake and on its islands.

Remarkable is such an integral part of the life of the great lake as the massive emergence of brown bears on the shores, which is entirely due to the peculiarities of the nature of Lake Baikal.

In the mountain taiga of the Baikal region, there is a musk deer - the smallest deer on the globe.

The diversity of the organic world of Baikal staggers the imagination, but its originality is no less phenomenal. Many animals and plants living in the lake are not found in any other body of water on the globe. There are 848 species of endemic animals (about 60%) and 133 species of endemic plants (15%) in Baikal.

BAIKAL FOR TOURISTS

Today, everything connected with Baikal arouses genuine interest not only in our country, but also abroad. Over the past decade, Baikal has become a magnet for many tourists. Relatively well-preserved nature
lake-seas, rapidly developing infrastructure - hotels, roads, proximity to transport interchanges - give reason to believe that in the future the tourist flow to the shores of Lake Baikal will only increase.

Come to Lake Baikal! Admire its beauty and purity of water, feel that almost mystical
energy that gives the sacred sea to everyone who comes to its shore.

Based on the article "The Unique Baikal", prepared by Valentina Ivanovna Galkina, Honored Worker of Culture of Russia, head of the exposition of the Baikal Museum of the Siberian Branch of the Russian Academy of Medical Sciences.