Lake Baikal is the most amazing lake in the world. Secrets of Lake Baikal

Baikal is a large lake in Russia, in the south Eastern Siberia, is located in a basin surrounded by mountain ranges. Administratively, it is located within the Irkutsk region and the Republic of Buryatia.

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This is the deepest lake in the world, its greatest depth reaches 1642 meters. It is also the world's largest natural reservoir of fresh water. The lake basin is of tectonic origin and is a rift.

Lake Baikal is one of the most interesting natural attractions in Russia. Since 1996 it has been a UNESCO World Heritage Site.

The size of this reservoir is truly impressive. The length of the lake from southwest to northeast is 620 km, and its width varies from 24 to 80 km. The area of ​​the reservoir is 31,722 square meters. km, and its length coastline– 2100 km.

Baikal is the deepest lake in the world with a greatest depth of 1642 meters. Moreover, the average depth of this unique reservoir reaches 744 meters. The volume of water is 23,615 cubic meters. km, which is approximately 19% of the total volume of fresh lake water in the world. The water surface is located at absolute levels of 456-457 m.

More than 300 different watercourses flow into Lake Baikal, the largest of which are the Selenga, Upper Angara, Barguzin, Turka, etc. The only river flowing from the lake is the Angara.

There are 27 islands on Lake Baikal, the largest of which is Olkhon. Its area is 729 square meters. km. The length of this island is more than 70 km, and the width is up to 15 km.

The water level in Baikal is subject to fluctuations. The difference between the highest and lowest annual levels usually does not exceed 23 centimeters. However, these seemingly small fluctuations lead to an increase or decrease in the volume of lake water by approximately 3 cubic kilometers. The level of Lake Baikal depends mainly on the amount of precipitation falling in its catchment area.

Baikal climate

During the cold period, it is always a little warmer near the lake, and during the warm period, it is cooler than in the surrounding area. In this respect, the Baikal climate is similar to the sea.

Mirror Baikal (Yuri Samoilov / flickr.com)

As in the case of the sea, such climate features are associated with the fact that in the summer a gigantic volume of lake water accumulates a huge amount of heat, and then, in autumn and winter, releases this heat back. This is how the softening effect of the lake manifests itself on sharply continental climate Eastern Siberia, characterized by strong contrast.

The warming effect of the lake extends approximately 50 km from its shores. In the cold season, the temperature on the coast of Lake Baikal can be 8-10 degrees higher than far from the lake, and in the warm season it can be just as much lower than the temperatures of the surrounding area. Typically, this difference is about 5 degrees. Baikal smoothes out not only annual, but also daily temperature fluctuations.

To a large extent, the climate of Baikal is determined by its inland location, as well as the altitude of the lake above sea level.

Average annual temperature and precipitation

The average annual temperature varies from 0.7 degrees below zero (in the south) to 3.6 degrees below zero (in the north). The tallest average temperature recorded in Peschanaya Bay in the west of the reservoir. It is 0.4 degrees above zero, which makes this bay the warmest place in all of Eastern Siberia.

The maximum amount of precipitation is characterized by the mountain slopes of the eastern and south-eastern coasts of Lake Baikal (1000 - 1200 mm), and the minimum - the western shore of the lake, Olkhon Island and the lower reaches of the Selenga (less than 200 mm).

Ice on Baikal

Baikal is under ice for about five months of the year. The timing of ice cover varies from the last week of October (shallow bays) to the beginning of January (deep water areas).

Winter evening on Lake Baikal, Siberia, Russia (Thomas Depenbusch / flickr.com)

Spring ice drift begins at the end of April, and the lake is completely free of ice only in the first half of June.

The ice thickness by the end of winter is about one meter, in the bays - up to two meters. The ice of Lake Baikal is interesting because, especially severe frosts it is broken by cracks into separate ice fields. The width of such cracks reaches 2-3 m, and their length is many kilometers.

The cracking of the ice cover is accompanied by loud, booming sounds. In addition, the Baikal ice is famous for its amazing transparency.

Wind

A characteristic feature of the Baikal climate is its winds, each of which has its own name. The most powerful wind of Lake Baikal is the sarma, whose speed reaches 40 m/s, and sometimes up to 60 m/s. This is a strong squally wind blowing in the central part of the lake, from the valley of the Sarma River. Other winds of Baikal: Barguzin, Verkhovik, Mountain, Kultuk and Shelonnik.

Another one interesting feature local climate - a very large number of clear days a year, the number of which is even greater than on Black Sea coast Caucasus.

Nature of Baikal: flora and fauna

The Baikal flora is very diverse and rich, it includes more than 1000 plant species. The slopes of the mountains located along the shores of the lake are usually covered with taiga.

Baikal cow, Siberia, Russia (Daniel Beilinson / flickr.com)

Siberian cedar and larch are found in abundance in the local forests. Birch, poplar, aspen, currant trees, etc. grow along the rivers. As for aquatic plants, then there are approximately 210 species of algae. The fauna of Baikal is represented by more than 2,600 species and subspecies, more than a thousand of which are endemic. The 27 species of fish that live in the lake do not live in any other body of water in the world.

There are many species of fish in Baikal. The most unusual thing is the viviparous fish golomyanka, which is endemic to Lake Baikal. The main commercial fish is the Baikal omul. More than 80% of the biomass of all zooplankton is made up of another endemic species - the epishura crustacean. This crustacean purifies water, playing the role of a filter, and also serves as an important part of the diet of the Baikal omul and other organisms.

Nerpa on Baikal (Sergey Gabdurakhmanov / flickr.com)

Another famous endemic of the lake is Baikal seal, which is the only freshwater seal in the world. The largest rookeries of this most interesting animal are located on the Ushkany Islands, in the central part of Lake Baikal.

There is still debate among scientists about how the Baikal seal entered the lake, which is so far from the oceans. It is assumed that it penetrated into Baikal from the Arctic Ocean along the Yenisei and Angara during the Ice Age. Of the animals that live in the Baikal forests, we can note brown bear, wolverine, musk deer, wapiti, elk, fox, squirrel, etc.

Baikal is home to 236 species of birds, of which 29 species are waterfowl. Ducks and seagulls are found here in large numbers. You can also see geese, screaming swans, gray heron, black-throated loon, golden eagle, etc.

Ecology

The unique nature of Baikal is distinguished by its fragility. All living organisms here react very sensitively to the slightest changes in environmental conditions. The process of decomposition of pollutants in the lake proceeds very slowly. The ever-increasing anthropogenic load cannot but affect this fragile ecosystem.

Boat on Baikal (-5m / flickr.com)

Of the enterprises located directly on the shores of the reservoir, the most famous is the Baikal Pulp and Paper Mill, founded back in the 1960s.

Bottom runoff from the Baikal pulp and paper mill spreads along the underwater slope of the Baikal depression. The area of ​​the pollution spot covers about 299 square meters. km. Due to the bottom runoff from the pulp and paper mill, the bottom ecosystems of Lake Baikal are degraded, and emissions from this enterprise into the atmosphere negatively affect the adjacent taiga.

Despite many protests by environmentalists and activists, the Baikal Pulp and Paper Mill continued to produce pulp until the end of 2013. Now the plant has ceased operations, however, it will take many more years to eliminate its waste and restore the environment.

The pollution of this unique reservoir did not end with the closure of the pulp and paper mill. A major source of pollution of the lake is its most important tributary, the Selenga River, in the basin of which there are such large cities as Ulaanbaatar and Ulan-Ude, as well as numerous industrial enterprises in Mongolia and Buryatia.

Partial pollutants come even from the territory Trans-Baikal Territory, from settlements located along the tributaries of the Selenga. Most of the treatment facilities in small settlements of Buryatia are not fully capable of handling wastewater treatment.

Poachers cause serious damage to the flora and fauna of the reservoir.

Tourism

Lake Baikal is one of the most popular tourist sites in Russia, recognized by UNESCO as a World Heritage Site. The starting points of most trips to the very deep lake in the world are Irkutsk (southwestern part of the reservoir), Ulan-Ude (east of the lake) and Severobaikalsk (northern tip). From these cities it is most convenient to start your route directly to the lake.

Old motorcycle against the backdrop of Lake Baikal (Vladislav Bezrukov / flickr.com)

South of Irkutsk, at the mouth of the Angara, is the village of Listvyanka, which is the most popular resort on Lake Baikal. There is a developed tourist infrastructure here, in addition, numerous excursions are organized from here. The cities of Slyudyanka and Baikalsk are also located on the southwestern coast of the reservoir. On the eastern coast there is the recreational zone Baikal Harbor.

Another well-known center of attraction for tourists is Olkhon Island, characterized by a variety of natural landscapes. You can get to Olkhon by ferry from the village of Sakhyurta; largest locality islands - the village of Khuzhir, where there is a fairly developed tourist infrastructure.

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

The shortest line running across the area of ​​the lake and connecting the most distant points of its shores, i.e. the length of the lake is 636 km, the greatest width of Baikal, equal to 79.4 km, is located between Ust-Barguzin and Ongureny; the smallest, different 25 km, is located opposite the river delta. Selenga.

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 very unevenly relative to the area of ​​the lake itself (see map of the basin). Along the entire western shore, the border of this area runs just a few kilometers from the shore of the lake. It is bordered almost everywhere by the watershed of the mountains visible from the lake.

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

The Lena River basin comes directly to this watershed throughout northern Baikal, and the Lena itself originates 7 km from the shore of Baikal near Cape Pokoiniki. Nai greater distribution has the Baikal drainage area to the south and southwest of the lake towards the Selenga River basin. The basin of this river, equal to 464,940 square meters. km, makes up 83.4% of the total catchment area of ​​Lake Baikal. The next largest basin is the Barguzin River, whose basin is 20,025 square meters. km and accounts for 3.5% of the total catchment area of ​​Lake Baikal. All other tributaries of Lake Baikal share a drainage area of ​​72,035 square meters. km, equal to 13.1% of the total drainage area of ​​the lake.

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

In the south, along its eastern shores, the snow-covered peaks of the Khamar-Daban ridge stretch almost all year round, with the highest altitudes up to 2000 m above sea level. This is exactly the chain of mountains that is visible to anyone passing along the shores of Lake Baikal by rail. These mountains are especially clearly visible on the stretch between the station. Baikal and Art. Kultuk. The Pribaikalsky ridge adjoins the western shores of southern Baikal. Its height along almost the 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 to the northernmost tip of the western shores of Baikal, the Baikal mountain range stretches, gradually rising north from Cape Ryty to Cape Kotelnikovsky. In this section, Mount Karpinsky reaches greatest height at 2176 m, Mount Sinaya - 2168 m, etc. Almost along the entire length of the peaks of the Baikal ridge are covered with snow that does not melt even in summer, and in many places traces of glaciers that recently descended from them are visible.

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

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

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

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

There are 19 permanent islands on Lake Baikal, the largest of which 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 the “Olkhon Gate”, elongated in a north-east direction, is a mountain range, with the highest point - Mount Izhimei, reaching a height of 1300 m and steeply plunging to the east shore. The northern part of the island is wooded, and the southern part is completely devoid of woody vegetation and is covered with meadows with traces of the steppe vegetation that was apparently once widespread here.

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

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

The remaining islands on Lake Baikal are all located near its shores, four of them are in the Chivyrkuisky Bay (Bol. and Mal. Kyltygei, Elena and Baklaniy), 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 Lake Baikal, such as Listvenichny, Boguchansky, Baklaniy (near Peschanaya Bay), etc.

All islands have a total area of ​​742.22 square meters. 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 Lake Baikal, which are completely hidden under water in high water and protrude above the surface only when the waters are low. These are the islands, elongated in the form of narrow strips, separating Proval Bay from Baikal (Chayachy Islands, Sakhalin), and these are the islands separating the Angarsky Sor from open Baikal - the so-called Yarki. The islands that separate Istoksky Sor from open Baikal also belong to the same type.

Bays and bays, so important for the settling of small ships, are a relatively rare phenomenon on Lake Baikal, and moreover, they are distributed very unevenly 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 gulf is the so-called Small Sea, separated from open Baikal by the island of Olkhon and Proval Bay, north of the Selenga delta.

Peschanaya and Babushka bays on the western shore of southern Baikal are famous for their picturesqueness. Further, a unique group of bays, or rather lagoons, called “sorov” on Baikal, are its former bays separated from the open lake by narrow sandy spits. These are the Posolsky and Istoksky soras, separated from Lake Baikal by narrow strips of land washed up 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 sand spits, sometimes completely hidden under the surface of the lake in high water.

Apart from these large bays, almost separated from Lake Baikal by its sediments, then all other bends of its coast largely depend on the direction of the Baikal coastline, since the tortuosity of its coast depends on whether the coast is directed along or across the dominant direction of the mountain ranges composing the shores.

Those sections of the shore of Lake Baikal that are directed across the main direction of the mountain ranges that limit its basin are characterized by significant ruggedness, such as the Olkhon Gate or the southern shore of the Barguzin Bay. The same sections of the coast, which in their direction coincide with the direction of the mountain ranges limiting the Baikal basin in this area, are characterized, on the contrary, by exceptional straightness, broken only by secondary accumulations of coastal sediments or the eroding action 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, this is the area that borders 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 very often almost sheer cliffs, many meters high, drop into the water. Particularly characteristic in this regard is the area between Sosnovka and the entrance to Chivyrkuisky Bay on the eastern shore of middle Baikal or the area from Onguren to Cape Kocherikovsky on the western shore of middle Baikal.

Based on the depth distribution or bottom topography, Baikal can be divided into three main deep depressions. The first of them is the southern one, occupies the entire southern Baikal to the confluence of the river. Selenga. The greatest depth of this depression is 1473 m, 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 on the opposite slopes.

Lake sediments at the bottom of the southern depression have not completely smoothed out the features of the original relief, at the bottom of which there is a series of hollows and irregularities adjacent to the Transbaikal coast and elongated in the northeast direction. These underwater ridges are especially pronounced in the part of the depression adjacent to the river delta. Selenga, and are hidden under its sediments. One of these ridges protrudes so significantly that it forms in the middle of the width of Lake Baikal on the line between the village. Goloustny and s. Posolsky shallow water, where depths of 94 m were discovered, and the depths in this shallow water have not yet been sufficiently explored and one cannot guarantee that even shallower depths will not be found there. This shallow water is, in all likelihood, the remnant of what was noted here on old maps Stolbovoy Island, partly destroyed by the waters of Lake Baikal, partly sank below its surface.

On the bridge separating the southern deep depression of Lake Baikal from its middle depression, 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, elongated in front of the Selenga delta, extending far in both the southwestern and northeastern directions and known among local residents called "manes". In its part adjacent to the Selenga, this bridge is gradually significantly modified by the Selenga outfalls.

To the east of the mane directed to the northeast, approximately opposite the channel of the Selenga delta, called Kolpinnaya, there is a bottom depression reaching 400 m and locally called the “abyss”. A legend is associated 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 area of ​​the depression there is a local whirlpool, clearly visible on quiet days, when all sorts of objects floating on the surface receive a rotational movement. This whirlpool, which gives the impression that water is being drawn into the hole below, as our research has shown, 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 depression of Baikal occupies the entire space between the bridge 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 Lake Baikal, reaching 1741 m. This depth is located at a distance of 10 km opposite Cape Ukhan on Olkhon. The average depth of the depression reaches 803 m. The area occupied by depths greater than 1500 m, not found in the other two deep depressions of Lake Baikal, is 2098 square meters. 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 areas adjacent to the eastern shore of the depression are flatter, and depths of 100 m in some places are located here several kilometers from the coast.

The Barguzinsky Bay, which forms part of the middle depression, has a very complex bottom topography. It is divided into two depressions by an underwater ridge. The part of the bay adjacent to the southern head of the Svyatoy Nos peninsula has depths of over 1300 m, which extend far into its northern part. The bottom topography of the entire eastern part of the bay is influenced by the river discharges. Barguzin, which covered the bedrock topography with a thick layer of sediment.

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

This ridge, on which depths do not exceed 400 m, stretches from the northern tip of Olkhon Island to Ushkany Islands and then, less sharply defined, to the north to Cape Valukan. Thus, the Ushkany Islands themselves are only the northern part of the Academic Range 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 depression of Baikal occupies the entire space located north of the Academichesky Ridge 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 exceptional flatness 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 descends more steeply into the depths than near the eastern shores, where there are significant shallows.

Most of the surface of the bottom of Lake Baikal at depths of over 100 m is covered with thick deposits of silt, which mainly consists of countless shells of dead algae that lived in the sea and fallen to the bottom. upper layers water. Only in a few places, such as the Academichesky Ridge, the bottom of Baikal consists of bedrock; there are also areas of the bottom where, at great depths, you can find rounded boulders and pebbles; apparently, these are the flooded beds of ancient rivers, not covered with silt deposits due to the bottom currents existing there.

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

However, Baikal did not always have those character traits bottom relief and the shape of its outline that it currently has. There is reason to assert the opposite, namely, that Baikal in its modern form was formed with geological point view, relatively recently - at the end of the Tertiary or even at the beginning of the so-called Quaternary time. According to modern views of geologists, the formation of the great depths of Baikal, as well as the formation of those mountain ranges that border the lake, date back to this time. There is little information about what the reservoir that was on the site of Baikal before this time was like.

Apparently, it was a complex system of lakes connected by straits and occupying a larger territory 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 present state is, to a certain extent, the remnant of reservoirs that once occupied a vast area and were repeatedly subjected to significant changes. How could this affect the composition of the animal and flora Baikal, we will look at it below in the corresponding chapter.

During 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 Lake Baikal only in isolated places. Piles 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 never completely covered the surface of Baikal.

Moraines left after the Ice Age had a significant influence on the formation of the shores of Northern Baikal. Some capes in the north of Lake Baikal are made of moraine materials, such as Cape Bolsodey. On the eastern shore of Northern Baikal, where many capes are also made of moraine material, they were subject 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 underwater rocks dangerous to 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 enormous depths was formed in its modern form.

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

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

There are other geologists who also connect 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, dates back to the second half of the Quaternary period, i.e. to the time of primitive man.

Finally, according to the latest views of E.V. Pavlovsky, the Baikal depressions and the ridges separating them are so-called synclines and anticlines, complicated by faults and developed gradually over many geological epochs, against the background of a general arched uplift of the Stanovoy 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 Tertiary time, the northern one - on the border of Tertiary and Quaternary time. The basins and the surrounding ridges are blocks into which the Baikal region was broken during the last eras of mountain building. The descending blocks turned into basins, and the rising ones - into ridges. We have a whole range of evidence that the formation Baikal basin continues to this day, and that the bottom of the basin continues to descend, and its edges in the form of limiting Baikal depressions of mountain ranges rise.

Signs of bank subsidence, villages. Ust-Barguzin in 1932. Photo by G.Yu. Vereshchagina

The subsidence of the shores of Lake Baikal 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 Verkhnyaya Angara rivers, as well as in areas far beyond Baikal basin delta Selenga. In all these places, not only are there features of the coastline that indicate a gradual subsidence of the shore below the lake level, but there are also historical facts confirming this. So the village of Ust-Barguzin has already changed its location 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 still in a semi-flooded state. A similar phenomenon is observed in the village located at the mouth of the river. Kichery (Nizhneangarsk), where once was the center of the entire region, and now only a small number of houses remain. In the Selenga delta, the subsidence of the area is expressed in the fact that there is a gradual swamping of the meadows of the delta and the transformation of once dry meadows and even fields into a swamp.

But the most significant is the lowering of part of the bank in the river area. 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, and a strong vertical blow was felt, from which the soil on the steppe swelled up in mounds and sand, clay and water were thrown out of the resulting wide cracks. The steppe was flooded with water, gushing out in fountains more than two meters high. And the next day, the water of Baikal flooded the entire subsided space up to the Bortogoy steppe. According to eyewitnesses, water came out of the lake like a wall. In place of the steppe, Proval Bay currently stretches out with depths of up to three meters.

Secondary redistribution of sediment along the coast leads to a number of changes in the nature of the Baikal coastline, of which we will point out only the most important. 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 sloping shores to the water's edge, made of sand or small pebbles, which are usually good non-water sinks.

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 Lake Baikal connects, as already noted, the once rocky island of Svyatoy Nos with the continent, turning it into a peninsula. Typical bridges made of sediment are observed on some capes of the Small Sea, like Kurminsky, which was also once an island and only secondarily attached to the shore by sediment. 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 rampart near the mouth of the river. Yaxakan ( East Coast northern Baikal). Photo by L.N. Tyulina

The movement of sediment along the shore also leads to the detachment of its bays from the lake. It is this process that causes the formation of its so-called litters on Lake Baikal. Once upon a time these were just curves of the coast - bays. To the side of these bays along the shores, under the influence of the prevailing direction of the surf, the movement of sediments occurred, which, having reached the bay, were deposited on its bottom in a direction that was a continuation of the general direction of the coast in this area. This is how narrow sandy islands, elongated in the form of strips, arose, with which the sors are gradually separated from Baikal. In some cases, such bridges have already led to the almost complete disconnection of bays from the lake, such as Posolsky Sor. In other cases, this process is not completed, such as the Istoksky litter, or it is just beginning, which is the case in Proval Bay.

In the cases prevailing on Lake Baikal, coastal sediments accumulate weakly near its shores, and as a result, the very shores are exposed to the destructive action of the surf. Some sections of the coast are literally chewed up by the surf. Up to a height of 5 meters or more, the rocks have been destroyed, representing cliffs with an uneven, jagged surface, and in many places niches and caves have been carved into the rocks by the surf.

The destruction is especially severe 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 islands, as if cutting them off near the water's edge. It is in this state, very close to complete destruction, that the Malye 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 once was in the middle of Lake Baikal between Goloustnoye and Posolsky and marked on ancient maps, but 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 Yedor arose in this way.

Tremendous waves that cause strong surf, as well as the roughness of the lake, in which this wave is repeated very often, causes an exceptionally strong influence of the surf on the shores and leads to both their destruction and the movement of sediments and the formation of shore areas washed up by the lake. Baikal is a classic place for studying the work of a lake on its shores, which has not yet been adequately appreciated in this regard.

The shores of Lake Baikal diverge by 2 centimeters annually

Features of the lake

The lake is located in a seismological zone; several hundred earthquakes occur in its vicinity every year. Mostly with an intensity of 1–2 on the MSK-64 scale. The predominant part of tremors can be detected only by highly sensitive equipment. The transformation of Lake Baikal continues to this day.

The Baikal winds give the local climate distinct features. They often whip up a storm on the lake and have memorable names: barguzin, sarma, verkhovik and kultuk. Water mass affects the atmosphere of coastal areas. Spring here comes 10–15 days later than in neighboring areas. Autumn lasts for a long time. Summers are usually cool, and winters are not very frosty.

Two large lakes and many streams create the main stream flowing into Baikal. The Selenga River, originating in Mongolia, provides most of the inflow from the southeast side. The second large influx is from the eastern bank, from the Barguzin River. Angara – the only river, flowing from Lake Baikal.

The purest waters of Lake Baikal make up 19% of the world's fresh water reserves

The water contains a minimal amount of mineral salts and is abundantly saturated with oxygen to the very bottom. In winter and spring it is blue and becomes most transparent. In summer and autumn it acquires a blue-green hue and is maximally heated by the sun. IN warm water Many plant and animal species are formed, so its transparency decreases to 8–10 m.

In winter, the surface of the lake is covered with a thick layer of ice, riddled with multiple, many-kilometer-long cracks. Explosions occur with a piercing crack, similar to gun salvos or peals of thunder. They divide the ice surface into separate fields. The cracks help fish avoid dying due to lack of oxygen under the ice. The sun's rays penetrate through the transparent ice. This promotes the development of planktonic algae that produce oxygen. Baikal freezes almost completely, not counting the area at the headwaters of the Angara.

Baikal as an ecosystem

More than 3,500 species of animals and plants live in water and on land. Numerous studies New species are often discovered, and the list of inhabitants continues to grow. About 80% of the fauna are endemic, found exclusively in Lake Baikal and nowhere else on earth.

The banks are mountainous and covered with forests; All around there is impenetrable, hopeless game. An abundance of bears, sables, wild goats and all sorts of wild things...

Anton Pavlovich Chekhov

Baikal has a large amount of valuable fish: sturgeon, burbot, pike, grayling, taimen, whitefish, omul and others. 80% of the lake's zooplankton biomass is the epishura crustacean, which is endemic. It passes through itself and filters water. The golomyanka, a viviparous fish that lives on the bottom, looks unusual and contains more than 30% fat. Biologists are surprised by its constant movements from the depths to the shallows. Freshwater sponges grow at the bottom.

According to the stories of local residents, until the 12th–13th centuries the Baikal region was inhabited by the Mongol-speaking Bargut people. Then the Buryats began to actively settle on the western coast of the lake and in Transbaikalia. The Russian discoverer of Baikal was the Cossack Kurbat Ivanov. The first Russian-speaking settlements appeared at the end of the 17th – beginning of the 18th centuries.

Mysteries of Lake Baikal

The crystal waters of Lake Baikal are fraught with many mysteries. Often legends and stories about the lake maneuver on the verge of mysticism and real stories. Researchers have discovered a lot of meteorite debris and inexplicable linear arrangements of underwater rocks at the bottom of Lake Baikal. Some believe that the waters of the lake contain Pandora's casket and the magic crystal of Kali-Ma. Others claim that Kolchak’s gold reserves and Genghis Khan’s gold reserves are hidden here. There are witnesses who claim that a UFO route passes over the lake.

The ice cover hides many secrets, forcing scientists to make speculative conclusions. Unique forms of ice cover, unique to Lake Baikal, were found by specialists from the Baikal Limnological Station. Among them: “juice”, “kolobovnik”, “autumn”. The ice hills are shaped like tents and have an opening on the back side of the shore. Dark rings were discovered on satellite imagery. Scientists believe that they are formed due to the rise of deep waters and an increase in the temperature of the water surface.

There is still scientific debate about the origin of Baikal. According to one version put forward by Doctor of Geological and Mineralogical Sciences A.V. Tatarinov in 2009, after the second stage of the “Mirov” expedition, the lake is considered young. Scientists have studied the activity of mud volcanoes on the bottom surface. After this, they made an assumption: the age of the deep-sea part is 150 thousand years, and the modern coastline is only 8 thousand years old. The oldest lake on earth does not show any signs of aging, like other similar reservoirs. According to the results of recent research, some experts are inclined to conclude that Baikal can become a new ocean.

Recreation and tourism on Baikal

Favorable time for a holiday on Lake Baikal is from mid-July to mid-August. At other times, it becomes cold on the coastal area, and the conditions are more suitable for fans of extreme recreation. But even in the summer, sometimes a cyclone comes with a cold wind and sharp temperature changes between day and night. An important condition safe holiday is a detailed study of the travel route.

The most visited vacation spots are the Circum-Baikal Railway, Sandy Bay, the village of Listvyanka, the coast of the Small Sea, Sandy Bay, the western coast of Olkhon, the coast near the city of Severobaikalsk. Other places that can be reached by SUV are also popular.

Baikal, it would seem, should suppress a person with its grandeur and size - everything in it is large, everything is wide, free and mysterious - but on the contrary, it elevates him. You experience a rare feeling of elation and spirituality on Baikal, as if, in view of eternity and perfection, you were touched by the secret seal of these magical concepts, and you were doused with the close breath of an omnipotent presence, and a share of the magical secret of all things entered into you. You are already, it seems, marked and highlighted by the fact that you stand on this shore, breathe this air and drink this water. Nowhere else will you have such a complete and so desired feeling of unity with nature and penetration into it: you will be intoxicated by this air, whirled and carried away over this water so quickly that you will not have time to come to your senses; you will visit such protected areas that we never dreamed of; and you will return with tenfold hope: there, ahead, is the promised life...

Valentin Grigorievich Rasputin

Numerous scientific studies have been devoted to the problem of the origin of the word “Baikal,” which indicates a lack of clarity on this issue. There are about a dozen possible explanations for the origin of the name. Among them, the most probable version is considered to be the origin of the name of the lake from the Turkic-speaking Bai-Kul - rich lake.

Of the other versions, two more can be noted: from the Mongolian Baigal - rich fire and Baigal Dalai - large lake. The peoples who lived on the shores of the lake called Baikal in their own way. Evenks, for example, - Lamu, Buryats - Baigal-Nuur, even the Chinese had a name for Baikal - Beihai - North Sea.

The Evenki name Lamu - Sea was used for several years by the first Russian explorers in the 17th century, then they switched to the Buryat Baigal, slightly softening the letter “g” by phonetic replacement. Quite often Baikal is called the sea, simply out of respect, for its violent temper, because the distant opposite shore is often hidden somewhere in the haze... At the same time, a distinction is made between the Small Sea and the Big Sea. The Small Sea is what is located between the northern coast of Olkhon and the mainland, everything else is the Big Sea.

Baikal water

Baikal water is unique and amazing, like Baikal itself. It is unusually transparent, clean and saturated with oxygen. In not so ancient times, it was considered healing, and diseases were treated with its help. In spring, the transparency of Baikal water, measured using a Secchi disk (a white disk with a diameter of 30 cm), is 40 m (for comparison, in the Sargasso Sea, which is considered the standard of transparency, this value is 65 m). Later, when massive algae blooms begin, the transparency of the water decreases, but in calm weather the bottom can be seen from a boat at a fairly decent depth. Such high transparency is explained by the fact that Baikal water, thanks to the activity of living organisms living in it, is very weakly mineralized and close to distilled.

The volume of water in Baikal is about 23 thousand cubic kilometers, which is 20% of the world's and 90% of Russian fresh water reserves. Every year, the Baikal ecosystem reproduces about 60 cubic kilometers of clear, oxygenated water.

Age of Lake Baikal

Usually in the literature the age of the lake is given as 20-25 million years. In fact, the question of the age of Baikal should be considered open, since the use of various methods for determining age gives values ​​from 20-30 million to several tens of thousands of years. Apparently, the first assessment is closer to the truth - Baikal is indeed a very ancient lake. If we assume that Baikal is actually several tens of millions of years old, then it is the oldest lake on Earth.

It is believed that Baikal arose as a result of tectonic forces. Tectonic processes are still ongoing, which is manifested in increased seismicity in the Baikal region.

Climate in the area of ​​Lake Baikal.

The climate in Eastern Siberia is sharply continental, but the huge mass of water contained in Baikal and its mountainous surroundings create an extraordinary microclimate. Baikal works as a large thermal stabilizer - in winter it is warmer on Baikal, and in summer it is a little cooler than, for example, in Irkutsk, which is located 70 km from the lake. The temperature difference is usually about 10 degrees. A significant contribution to this effect is made by forests growing almost along the entire coast of Lake Baikal.

The influence of Baikal is not limited to temperature regulation. Due to the fact that evaporation cold water from the surface of the lake is very insignificant; clouds cannot form over Baikal. In addition, the air masses that bring clouds from land heat up when they pass over the coastal mountains, and the clouds dissipate. As a result, the sky over Lake Baikal is clear most of the time. This is also evidenced by the numbers: the number of hours of sunshine in the area of ​​Olkhon Island is 2277 hours (for comparison - on the Riga seaside 1839, in Abastumani (Caucasus) - 1994). You should not think that the sun always shines over the lake - if you are unlucky, you can end up with one or even two weeks of disgusting rainy weather even in the sunniest place of Lake Baikal - on Olkhon, but this happens extremely rarely.

Average annual temperature water on the surface of the lake +4°C. Near the coast in summer the temperature reaches +16-17°C, in shallow bays up to +22-23°C.

Wind and waves on Baikal.

The wind almost always blows on Lake Baikal. More than thirty local names of winds are known. This does not mean that there are so many different winds on Baikal, just that many of them have several names. The peculiarity of the Baikal winds is that they almost always blow along the coast and there are not as many shelters from them as we would like.

Prevailing winds: northwestern, often called mountain, northeastern (barguzin and verkhovik, also known as angara), southwestern (kultuk), southeastern (shelonnik). Maximum speed wind recorded on Lake Baikal is 40 m/s. In the literature there are also higher values ​​- up to 60 m/s, but there is no reliable evidence for this.

Where there is wind, there are, as you know, waves. Let me immediately note that the opposite is not true - a wave can occur even with complete calm. Waves on Baikal can reach a height of 4 meters. Sometimes values ​​of 5 and even 6 meters are given, but this is most likely an estimate “by eye”, which has a large error, usually towards overestimation. The height of 4 meters was obtained using instrumental measurements in the open sea. The excitement is strongest in autumn and spring. Summer on Baikal strong excitement happens rarely, and calm often occurs.

Ichthyofauna of Baikal.

Depending on their habitat conditions, fish can be divided into several groups. Sturgeon, pike, burbot, ide, roach, dace, perch, and minnow occupy the coastal shallows and river deltas of Lake Baikal. Fish of Siberian mountain rivers: grayling, taimen, lenok inhabit small tributaries of the lake and its coastal zone. Omul, since ancient times considered a symbol of Baikal, inhabits its open and coastal part, whitefish, another famous resident of Baikal, inhabits only the coastal part.

The most remarkable group of Baikal fish are gobies, of which there are 25 species. The most interesting of them are the golomyankas. This miracle of Baikal is not found anywhere else in the world. Golomyanka is incredibly beautiful, shimmers blue and pink in the light, and if you leave it in the sun it will melt, leaving only bones and a greasy stain. It is the main and most numerous inhabitant of Lake Baikal, but rarely gets caught in fishermen’s nets. Its only enemy is the seal, for which it is the main food.

To preserve rare and endangered animals, there is a strict and complete ban on hunting, maximum conservation of the habitat, the creation of special nurseries, national parks, nature reserves and sanctuaries

Lake Baikal and its drainage basin belong to the unique geosystems of the world. Baikal is located in the central part of Eastern Siberia, not far from the conventional geographical center of Asia. The mountain basin of the lake represents the most important natural boundary of Siberia. In this area, the boundaries of various floristic and faunal habitats converge, creating biogeocenoses that have no analogues.

Baikal is one of the greatest lakes on the planet, a lake of “superlatives”: the deepest (1637 m) and the oldest (about 25 million years old), containing the largest number of endemics (more than 1000 species) and representatives of flora and fauna (more than 2600 species ), living in fresh water bodies of the Earth. The lake has a unique reserve of fresh water in terms of volume (23.6 thousand cubic km) and quality (20% of the world). The Baikal depression is the central link of the Baikal rift zone, which arose and is developing simultaneously with the world rift system. A number of factors suggest that the lake is an emerging ocean. The climate of the Baikal coasts is unusually mild for Siberia - the number of sunny days here is higher than in many Black Sea resorts. 336 rivers flow into Baikal (Selenga, Barguzin, Verkh. Angara, etc.), and one flows out - Angara.

The entire basin of the lake (the total catchment area is 557 thousand sq. km, of which 332 are in Russia) is a unique and very fragile natural geosystem, the basis of which is the system of the lake itself with its natural process of formation of the purest waters of drinking quality.

Baikal is the greatest lake on the planet

Baikal is one of the greatest lakes globe, the largest freshwater lake in Russia. Its length is 636 kilometers, its water surface area is 31,500 square kilometers. Baikal is 1.7 times larger than Lake Ladoga, the largest in Europe. Among the freshwater lakes of the world, it ranks sixth. There are two larger African lakes - Victoria and Tanganyika - and three of the five Great American Lakes - Superior, Huron and Michigan.

Baikal is not only one of the largest lakes, but also the deepest lake on the planet. As already mentioned, its greatest depth is 1637 meters.

The maximum depth of Tanganyika is 1435 meters, Issyk-Kul - 702. On Earth, only 8 lakes have a depth exceeding 500 meters (L. Rossolimo).

Tanganyika - fresh water, but its water contains a high content of magnesium salts. The entire thickness of fresh water deeper than 800 meters can only be studied in Baikal.

The average depth of the lake is also very large - 730 meters. It exceeds the maximum depths of many very deep lakes. This is what determines the water reserves in Lake Baikal.

Baikal is the largest freshwater lake on Earth in terms of water resources. Its volume is 23,600 cubic meters. kilometers, which is about 20% of the planet’s fresh lake waters - much more than in all the fresh lakes in the world. The volume of the latter is estimated at 123 thousand cubic kilometers of water. Baikal has more water than all five Great American Lakes combined. The Baikal volume of water is almost twice as much as in Lake Tanganyika, 90 times more than in the Sea of ​​Azov, 23 times more than in Lake Ladoga. Based on the current need of people for water, equal to 500 liters per person per day, Baikal water can provide the entire population of the Earth for approximately 40 years (G.N. Galaziy, 1984).

Geological features of the structure of Lake Baikal

The most remarkable feature of Baikal is its antiquity. Considering the deep relict endemism of the lake’s fauna, most researchers estimate its age at 20-30 million years. The vast majority of lakes, especially those of glacial and oxbow origin, live for 10-15 thousand years, then fill with sediment, become covered with rafts and sooner or later turn into swamps and then dry up. Research recent years allowed geophysicists to hypothesize that Baikal, on the contrary, is an incipient ocean. This is confirmed by the fact that its shores diverge at a speed of up to 2 cm per year, just as the continents of Africa and South America, the shores of the Mediterranean and Red Seas, etc. diverge. Along with active movements of the earth’s crust, significant magnetic anomalies along its axes. These anomalies are comparable in scale to similar anomalies in the Mid-Atlantic Rift region. The lake has many features inherent in the ocean - abyssal depths, a huge mass of water, internal waves and seiches, tides, strong storms, high waves, expansion of the basin due to the sliding of the shores, large magnitudes of magnetic anomalies, etc.

The lake lies in the Baikal depression - a bottomless stone bowl, surrounded on all sides by mountains. The depression is framed by the medium-high mountain ranges Primorsky and Baikalsky on the western side, Barguzinsky (with a maximum height of 2840 m) and Khamar-Daban on the eastern and southeastern sides. The depth of the depression is determined by the height of the mountains above it, the depth of the lake and the thickness of the loose sediment lining its bottom. The layer of these lake sediments in some places reaches 6,000 meters, and their volume is twice the volume of the lake and reaches 46,000 cubic kilometers. It is not difficult to calculate that the depth of the crystalline bed of Baikal reaches 8 - 9 kilometers.

The most deep point Baikal's bedrock lies approximately 7,000 meters below sea level. The Baikal depression is the deepest basin on earth's land. Its “roots” cut through the entire earth’s crust and go into the upper mantle to a depth of 50-60 kilometers.

Hydrology of Lake Baikal

Every year, Baikal produces about 60 cubic kilometers of excellent and unique quality water, which in some cases can be used instead of distilled water. The rare purity of the water is ensured by the vital activity of its unique flora and fauna. The main properties of Baikal water are characterized as follows: it contains very few dissolved and suspended minerals, negligible organic impurities, and a lot of oxygen. The total mineralization of water in Baikal is 120 milligrams per liter, while in many other lakes it reaches 400 or more milligrams per liter. The total content of ions in the lake water is 96.7 milligrams per liter.

Its transparency depends on the purity of the water. Baikal is not only extremely clean, but also the most transparent lake in the world. In the spring, after being freed from ice, the transparency of its water reaches 40 meters - tens of times more than in many other lakes. The standard of the highest transparency is the water of the Sargasso Sea, approaching the transparency of distilled water. Here the Secchi disk disappears from view at a record depth of 65 meters. Recent studies have shown that at depths of 250 - 1200 meters, the transparency of Baikal water is no less than in the Sargasso Sea.

Climatic characteristics

In terms of the number of hours of sunshine, Baikal is richer than the neighboring territories of Siberia and even some western and southern regions of the country - in the north of the Baikal depression (Nizhneangarsk) 1948 hours per year, in the south of the lake (Babushkin) and in the middle part (Khuzhir) 2100 and 2277, and on the Riga seaside, located at the same latitude - an average of 1839 hours per year, in Abastumani in the Caucasus - 1994. The average annual air temperature in the depressions of the lake is distributed as follows: in the southern basin -0.7 C, in the middle -1.6 C , in the north -3.6 C.

The water temperature in the surface layer varies from +14, +15 C (in August) to 0 C (in December-January). In coastal areas, during surges, the temperature can reach +16, +17 C, mainly under the eastern coast. In shallow bays and sora it rises in summer to +22, +23 C. On average, the freezing of Lake Baikal begins on December 21 and ends on January 16 - it takes about a month for complete freezing. From the beginning of the destruction of the ice cover in the southern basin, which occurs in April, to the complete cleansing of the entire reservoir in May-June, it also takes about a month or more. The most precipitation falls on the Khamar-Daban coast - about 800 mm/year or more, as well as in the mountains - from 1200 to 1400 mm; least of all - on the islands of Olkhon and Ushkany, on the Malomorsk coast of the lake and on the middle section of the western and eastern coasts. On average, precipitation falls here from 160 to 300 mm per year.

Flora and fauna

The exclusivity of many physical and geographical features of the lake was the reason for the extraordinary diversity of its flora and fauna. And in this regard, it has no equal among the fresh water bodies of the world. Almost half of all species of freshwater mollusks live in Baikal, as well as more than half of all species of oligochaetes, barnacles, etc. Of more than 2630 species and varieties (1550) of animals and plants (1085) found to date in the lake, almost 2 /3 are endemic, originated in it and are not found anywhere else in the world. Of the algae, the most numerous are diatoms - 509 species, tetrasporous and chlorococcal - 99, blue-green - 90, conjugates - 48, ulotrix - 45, golden - 28, volvox - 13 species, etc. Among animals, the most common amphipods (gammarids) - 255 species; shell crustaceans, or ostracods, - more than 100 species, gastropods - 83, oligochaetes - more than 100, planarians - about 50, harpacticids - 56, protozoans - more than 300. The lake is home to 52 species of fish belonging to 12 families: sturgeon, Acipenseridae, (1 species - Baikal sturgeon); salmonids, Salmonidae, (5 species - davatchan, taimen, lenok, Baikal omul, Coregonus autumnalis migratorius Georgy, whitefish); grayling, Thimallidae, (1 species - Siberian grayling); pike, Esocidae, (1 species); Cyprinidae, Ciprinidae, (13 species); loaches, Cobitidae, (2 species); catfish, Sibiridae, (1 species); codfish, Gadidae, (1 species); perciformes, Percidae, (1 species); sculpin gobies, Cottidae, (7 species); Abissocottidae, (20 species); golomyanka, Comephoridae, (2 species). 29 species - very diverse in body shape, color and lifestyle of sculpin gobies, or broadheads. Two species - viviparous fish, large and small golomyanka - are known to ichthyologists around the world.

The food pyramid of the lake ecosystem is crowned by a typical marine mammal - the seal, or Baikal seal, Pusa sibirica Gmel.

In Baikal there are 848 species of endemic animals - about 60% and 133 species of endemic plants - 15%. 11 families and subfamilies, 96 genera, uniting about 1000 species are completely endemic in Baikal. All this allows us to allocate the lake to the Baikal subregion of the Holarctic, equivalent in area to the enormous European-Siberian subregion.

Angara River

Angara is the “daughter of Baikal”, the only river flowing from the lake, its length is about 1860 km. Every year the Angara carries 60.9 cubic km of water from Baikal, and all its tributaries bring 58.75 cubic km per year. It is noteworthy that the Angara at the mouth, at the confluence with the Yenisei, brings 120 cubic km of water per year, and the Yenisei before the confluence of the Angara has a water flow of only about 100 cubic km. The source of the river is located at the level of Lake Baikal, i.e. at an altitude of 456 m above sea level, and the mouth is at an altitude of 76 m. The difference is 380 m, which is used by a cascade of hydroelectric power stations built on the Angara. The width of the Angara at the source is about 1 km, the depth varies in the range of 0.5 - 6 m, the flow speed along the fairway is 1-2 m/sec.

Baikal omul

The Baikal omul (Coregonus autumnalis migratorius Georgy) is an endemic fish that came to Baikal relatively recently (during the glacial or post-glacial period), presumably from the estuarine areas of rivers flowing into the Arctic Ocean. The omul has adapted well to its new ecological niche, undergone significant changes and acquired the biological characteristics of the subspecies. There are four populations of omul in Baikal: Selenga, Chivyrkui, Severobaikalsk and Posolsk. The most numerous population is Selenga. It spawns mainly in Selenga and in a number of tributaries of the lake. Inhabits the southern basin of Lake Baikal and the southern part of the middle basin. The omul spawns in rivers from the end of August - beginning of September until the end of November. The number of spawning herds ranges from one and a half to two to six to eight million individuals.

The total biomass of all age groups of omul in Baikal is about 25 - 30 thousand tons. The lifespan of the omul is up to 20 - 25 years, it spawns up to 6 times during its life at the age of 5 - 6 to 14 - 15 years. The average size and weight of each population is different. Size 30 - 35 cm, weight from 300 to 600 g. The largest specimen found in the Selenga population weighed up to 5 kg and was about 50 cm long.

Baikal seal

The Baikal seal (Pusa sibirica Gmel.) is the only representative of mammals in the lake. According to the classification, the seal belongs to the family of true seals (Phocidae), genus Pusa. Researchers believe that the Baikal seal descended from a common ancestor with the ringed northern seal. It is believed that the seal penetrated from the Arctic Ocean along the Yenisei and Angara during the Ice Age, when the rivers were dammed by ice advancing from the north. In the mid-80s, there were about 70 thousand seals in Baikal. The maximum age of the Baikal seal (according to V.D. Pastukhov) is 56 years for females and 52 years for males. Childbearing age lasts from 4-7 to 40 years, pregnancy lasts 11 months. During her life, a female can give birth to more than 20 cubs. The average weight of seals in Baikal is about 50 kg, the maximum weight of males is 130-150 kg, length 1.7-1.8 m. Females are smaller in size - 1.3-1.6 m and up to 110 kg. (+ video fragment - Baikal seal on the ice of the lake, 5-10 sec) (Based on materials from O.K. Gusev and G.N. Galaziy)

The nature of anthropogenic impact in the lake basin. Baikal.

Based on materials from TERKSOP Lake Baikal and " National report USSR to the 1992 UN Conference on Environment and Development" in the Lake Baikal basin there are 4 main areas of harmful anthropogenic impact on the ecosystems of the region.

1. The basin of the Selenga River in its lower reaches with 3 large industrial centers: Gusinoozerskaya State District Power Plant, Selenginsky Central Control Plant and Ulan-Ude. Ulan-Ude is the largest polluter of the Selenga, accounting for 53% of all wastewater discharged into the largest river in the Baikal basin. Above the city, the total concentration of impurities in the waters of the Selenga is 0.76 conventional units, below - increases to 62 conventional units. In 1988, the city's emissions of harmful substances into the atmosphere amounted to 152.2 thousand tons, of which 58.2 thousand tons came from industrial enterprises, 94 thousand tons from vehicles.

In the same year, the Selenga Central Control Plant emitted 44.1 thousand tons of pollutants into the atmosphere. The plant discharged 11.9 thousand tons of mineral substances, 3.4 thousand tons of organic substances and 135 tons of suspended matter into the waters of the Selenga. Air emissions from the Gusinoozerskaya State District Power Plant exceeded 63 thousand tons/year.

2. The southern end of the lake, where the main polluter is the Baikal Pulp and Paper Mill. In 1988, the plant's emissions into the atmosphere amounted to 30.4 thousand tons. harmful substances into the water of Baikal - 51.9 thousand tons of mineral substances, 4.7 thousand tons of organic substances and 532 tons of suspended substances. The maximum permissible concentrations (MPC) of petroleum products and phenols were exceeded 3-4 times, and the maximum permissible concentrations of sulfates and chlorides were exceeded. As a result of the plant's activities, a vast pollution zone was formed. The area of ​​bottom sediment contamination is 20 sq. km. Over the past 10 years, the number of benthic species of living organisms has decreased here from 27 to 10, and the biomass of zoobenthos has decreased by 3 times.

3. The valley of the Barguzin River in the middle and lower reaches. Here, the cut-down areas of the estimated logging area are significantly exceeded; 67% of the arable land is covered by erosion processes. Unregulated use of mineral fertilizers in this agricultural area may contribute to eutrophication of the lake.

4. Severobaikalsky area - a section of the coast between the cities of Severobaikalsk and Nizhneangarsk. The commissioning of the Baikal-Amur Railway significantly increased the anthropogenic load here. Atmospheric emissions of harmful substances in Severobaykalsk amounted to 15 thousand tons in 1988. The content of petroleum products in the water near Severobaikalsk is 3-5 MPC, the coli index is 238 tons. An additional source of pollution of Lake Baikal is the bank protection work carried out in this area.

The current influence of local anthropogenic sources in the lake basin is local in nature, but if we consider the characteristics of the atmosphere, it covers large parts of the lake, mainly its southern basin. This influence, in addition to local sources, is due to the transfer of air masses from the Irkutsk territorial complex, especially the Novo-Irkutsk Thermal Power Plant.