Baikal is one of the giant enclosed bodies of water on the planet. Not a single lake can compare with it in depth. Baikal has a significant share of the world's fresh water reserves. Its flora and fauna are extremely diverse. Baikal water is remarkable for its purity and transparency. The history of the study of the lake has been going on for more than three centuries, however, many mysteries remain related to its age and reasons for its origin.
Geographic location
Baikal is located in the southern part of Eastern Siberia, on the border dividing the territory of the Irkutsk region and the Republic of Buryatia. The lake is located in a crescent-shaped basin surrounded by rocks and hills. Its length is 620 km, the width varies from 24 to 79 km. The east coast is less rocky and steep than the west. The surface area is comparable with the territories of some European countries. It is 31722 km 2 . By this indicator, Baikal takes the seventh place on the planet. Only a few of the largest lakes of the American and African continents surpass it in the area of the water mirror.
Depth
The geological history of Lake Baikal has become the reason for its unique characteristics. Scientific studies confirm that this lake is the deepest in the world. It is worth considering that its water mirror is located at an altitude of 456 m above sea level. Hydrographic expeditions recorded and plotted the maximum value of the lake depth at 1642 m. Therefore, the bottom point extremely distant from the surface is located 1187 m below sea level. This record figure allows Baikal to be included in the list of the deepest depressions on the planet. Only Tanganyika Lake in Central Africa and the Caspian Sea can be compared with it, which is officially considered a closed reservoir, since it does not have access to the world ocean. Their depth exceeds 1000 m.
Water volume
The long history of the exploration of Baikal presented many surprises. It has been proven that it has the largest reserves of lake fresh water in the world. Its volume is 23615 km 3 . This is approximately 20% of global reserves. Only the volume of the Caspian Sea exceeds this value, but the water in it is salty, in contrast to Lake Baikal. The history of the appearance and development of special flora and fauna made the lake a unique ecological system. The fresh water of Baikal is of rare purity. The lake is a world record holder not only in its quantity, but also in quality.
Water characteristics
In the history of Baikal, a special place is occupied by the study of its flora and fauna. As it turned out, the lake water owes its unique purity to the local flora and fauna. All elements of the natural system are interconnected and influence each other. Baikal water is highly saturated with oxygen. It contains a negligible amount of dissolved minerals and organic impurities. Even pollution resulting from human activities does not lead to a significant deterioration in water quality. The development of industry and tourism industry does not pass without a trace for the ecological state of the lake. However, in its characteristics, water remains close to the distillation product obtained in laboratory conditions. One of the reasons for its amazing purity is the life of the microscopic crustacean. This representative of the fauna played an important role in the history of Lake Baikal. The crustacean multiplies in huge quantities and absorbs organic matter, naturally purifying the lake water.
Hypotheses of occurrence
The history of the origin of Lake Baikal causes some controversy. The lake is located in a large hollow that appeared at the site of the rupture of the earth's crust. The emergence of Lake Baikal is due to tectonic causes. Some researchers put forward the version that the depression was formed as a result of the interaction of two continental plates - Eurasian and Hindustan. Others claim that the lake is located in the transform fault zone. This type of rupture of the earth's crust occurs along the boundary of the lithospheric plate. In addition, there is a hypothesis that is poorly substantiated from a scientific point of view about the appearance of vacuum foci due to the release of volcanic rock onto the surface. In accordance with this version, this has led to a subsidence of the cavity.
Disputes about the history of the origin of Lake Baikal continue. However, increased seismic activity in this region leaves no doubt about the tectonic nature of the occurrence of the reservoir.
Age
Scientists differ greatly on the length of the history of Lake Baikal. The traditional version claims that the lake exists over 25 million years. This hypothesis raises certain doubts. Usually lakes are preserved in their original form no more than 10-15 thousand years. After that, due to the accumulation of a significant amount of silt at the bottom, they turn into swamps. A logical question arises: why, despite many millions of years of history, did Baikal not suffer the same fate?
There is an alternative version, indirectly confirmed by some studies. According to her, the lake is about 8 thousand years old. Of interest is the huge discrepancy between traditional and alternative theories. At present, the question of the age of Lake Baikal remains open.
Freezing
Even in summer, the water in the lake does not heat above 10 ° C. The maximum temperature recorded throughout the entire observation history is 23 ° C. In winter, the water mirror freezes almost completely. The thickness of the ice reaches 1 m, and in some places it can reach up to 2 m. In winter, fish in the lake does not suffer from a lack of oxygen. Due to severe frosts, cracks several meters wide are formed in the ice. Their length is 10-30 km. Through cracks, oxygen is saturated with water. This saves a large number of fish from death. The period of complete freezing of the lake usually lasts from January to May. Passenger and cargo navigation begins in June and ends in September.
Flora and fauna
About half of the species of living organisms living in Lake Baikal are not found anywhere else on the planet. This fact is explained by the isolation and antiquity of the ecological system of the lake. According to scientists, the fauna of Lake Baikal consists of 2600 species of animals. The reason for this diversity is the high concentration of oxygen in the water. This makes the lake a favorable habitat for all representatives of the animal world. The presence of a significant amount of oxygen persists even at great depths.
Of the fish that live in the reservoir, the most famous is the Baikal omul. He became in some way a symbol of the lake. The water column is inhabited by hundreds of species of flatworms, mollusks and crustaceans. At the bottom there are sponges that cover the stones with a solid outgrowth. They serve as a refuge for many living organisms.
Population
The history of the development of Lake Baikal began around the 2nd century BC. The first mention of the lake is contained in a Chinese manuscript of that era. According to archaeologists, 3 thousand years ago, the Baikal region was inhabited by Mongoloid tribes, the ancestors of modern Evenki. In the early Middle Ages, a nation appeared on the territory of southern Siberia, which in Chinese written sources was called "guligan." Its representatives were engaged in cattle breeding and agriculture, were able to smel metals. In the XVII century, the formation of the Buryat nationality from the Mongol-speaking tribes who migrated to southern Siberia from the west began.
The Russian history of the discovery of Lake Baikal is associated with the name of the Cossack Kurbat Ivanov. The expedition under his leadership reached the lake in 1643. Reports received by the tsarist government about the wealth of this region predetermined the further development of the history of Lake Baikal. Briefly described the lake in 1665, the famous Protopop Avvakum, who visited its shores on the way to exile.
Research
At the beginning of the 18th century, geographical maps of Baikal appeared. On the orders of Peter the Great, a scientific expedition led by physician Daniel Messerschmitt was sent to Siberia. She became the source of the first reliable information about the lake and its environs. Scientists who were part of the Great Northern Expedition led by Vitus Bering contributed to the study of Lake Baikal . They made a detailed description of the lake and collected extensive information about its flora and fauna.
The first hydrometeorological stations on Lake Baikal were founded in the second half of the 19th century. Their task was to conduct continuous monitoring of fluctuations in the temperature of the surface of the lake and changes in the water level in it. In those years, the foundation was also laid for studying the topography of the bottom.
Climate
In addition to many other unique features, Baikal is known for its unusual weather conditions. The rocky terrain and the presence of a giant mass of water in the lake soften the East Siberian continental climate. The air temperature in the vicinity of Lake Baikal is stable. Summer in the coastal zone is on average cooler than in the surrounding areas, and in winter there are no severe frosts. The Baikal climate is characterized by a long autumn and the late spring onset.