Why is there so much water in Lake Baikal? The super cisterns on earth are scary in comparison
Water is the source of life. It is because of the existence of water that various life forms are born on the earth. The abundance of water resources is one of the important factors for biological survival. The data shows that the total water storage of the earth is as high as 1.3 billion cubic meters, of which 97% is seawater, which cannot be directly drunk, and the remaining 3% is freshwater, but most of it is distributed in the poles of the earth and alpine glaciers, and the content of freshwater is less than that of earth water. 0.5% of the total resource. This kind of extremely uneven distribution of freshwater resources is rare in the country. There is a lake, one-fifth of the surface liquid freshwater resources in the world is obtained by its own power, which is the famous Lake Baikal.
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The former North Sea, also known as Lake Baikal, has the world's largest amount of fresh water. Why can it hold so much water?
There is a lake in Irkutsk, Siberia, Russia, which is Lake Baikal. The lake covers an area of 31,500 square kilometers, ranking sixth among the freshwater lakes in the world in terms of lake area. The top five are Lake Silio in North America (with an area of 82,000 square kilometers) and Lake Victoria in Africa (with an area of 69,000 square kilometers). square kilometers), Lake Huron in North America (with an area of 59,600 square kilometers), Lake Michigan in the United States (with an area of 58,000 square kilometers), and Lake Tanganika in Africa (with an area of 33,000 square kilometers).
However, the average depth of Lake Baikal is as high as 730 meters, with a maximum depth of more than 1,600 meters, which is the deepest lake on earth. Although the water area of Lake Baikal is relatively small, due to the influence of the depth of water filling, its water storage capacity has been greatly improved. Its freshwater storage volume reaches 23.6 trillion cubic meters, and the total fresh water of the world's surface rivers and lakes is about 120 trillion cubic meters. , of which nearly one-fifth of Lake Baikal's water volume is present.
If the concept of 2.3 trillion cubic meters is used to illustrate the water storage situation of Lake Baikal, it is very intuitive and can be compared with other more familiar lakes. First, take the Great Lakes in North America as an example. The Great Lakes are the largest freshwater waters in the world. The area of Lake Slior alone is nearly three times that of Lake Baikal. Among the 10 largest lakes in the world, 5 are the largest. 4 of them are on the list. However, such a huge group of freshwater lakes is less than 100 meters because of the small average water depth, and the total water storage capacity is only 22.8 trillion cubic meters, which is slightly lower than Lake Baikal.
Compare it with the largest lake in China, Qinghai Lake. Qinghai Lake is a salt lake with a total area of 4,330 square kilometers, an average water depth of only 21 meters, and a water storage of 74 billion cubic meters. The area of Lake Baikal is dozens of times that of Qinghai Lake. This number is indeed surprising. In addition, China has a large number of rivers and lakes, but the total water volume of these rivers and lakes is really insignificant compared to Lake Baikal. The total water volume of lakes and rivers (including salt lakes) in the country is 2.8 trillion cubic meters, accounting for only 12% of the total water volume of Lake Baikal. Now you know why Lake Baikal is the largest freshwater lake on earth.
Why does Lake Baikal hold so much water? The reason for this is because the depth of Lake Baikal is too great. If the water of Lake Baikal is pumped out, what will appear in front of us is a "Great Rift Valley" that is almost comparable to Africa. There is an inseparable connection between the geological structure and the results of geological movements in the region.
Located between the Asian European plate and the Amuya plate in eastern Asia is the area of Lake Baikal. Due to the continuous drifting motion of the earth's plates, the two plates are just separated, which is one of the most representative geological plates on the earth. Ground lakes are lakes formed by infiltration and silting of rivers, and there are many types of lakes, such as York Lake formed by diversion of rivers, dammed lakes formed by geological activities, and glacial lakes formed by melting glaciers. The tectonic lakes formed by cracks in the stratum, as well as the artificial lakes excavated by man, are undoubtedly lake structures from the background of the geological and historical evolution of Lake Baikal.
Due to the long-term geological action, the tectonic units on both sides of Lake Baikal gradually separated, causing the surface rock layers to collapse. The rivers around Lake Baikal, under the influence of the topography , gradually gathered here, and finally filled the entire crack. This is the deepest and most watery lake in the world, where geological fissures continue, with an area of about 5 mm a year, so the water storage of Lake Baikal is still increasing.
Moreover, the biological resources of Lake Baikal are very unique. According to geological survey, Lake Baikal has been formed for nearly 25 million years. After a long period of development, there have been many biological resources in Lake Baikal that are not found in other areas, such as sharks, sponges, conch, seals, etc. Just looking at the names of these animals, it seems that Lake Baikal is an ocean. However, from the research of scientists, this place has no relationship with the ocean in history, and it is completely different from the formation mechanism of the ocean. The Caspian Sea is a part of the ocean, but the edge is raised due to geological influences, causing part of the Caspian Sea to be separated from the ocean now, forming the Inner Sea. During the formation of Lake Baikal, it is believed that plate drift caused rock layers to break up, and that water from surrounding rivers pooled together due to the force of gravity.
Lake Baikal, which does not belong to the sea, exists like the sea. Why is this? Surveys have shown that the sharks in Lake Baikal are just a freshwater fish called dwarf fish, which are similar to sharks. The sponges and conch shells in Lake Baikal are also one of the species of freshwater sponges and conch shells.
Historically, the ancestors of the Baikal seals did come from the Arctic Ocean, but as the temperature of the Arctic sea increased, they eventually descended from the river south to Lake Baikal. Later, with the change of climate, the water volume of the river decreased and the river surface narrowed. The seals used it as a migration carrier, but they could never go back. Due to the deterioration of the living environment and lack of food, the seals went deep into the hinterland of Siberia, but not yet. The seals that reached Lake Baikal died one after another.
Part of Lake Baikal is a habitat for seals, where the waters are vast, the environment is pleasant, the food sources are abundant, and there are almost no natural enemies. In the evolutionary process of millions of years, due to the long-term isolation of geographical space, the appearance and reproduction of seals have gradually separated, forming the custom of "settling down", and finally forming a unique breed of Baikal seals.