Baikal

Lake Baikal is the largest freshwater lake in Asia and the seventh largest lake in the world. The water of the lake is clear and of high quality, which can be directly drunk without worrying about pathogens in the water, because the amphipod shrimp, a specialty of Lake Baikal, can filter the water 50 meters below the lake surface 7 to 8 times a day.

The lake is 680 kilometers long from north to south and 40 to 50 kilometers wide from east to west (the widest part can reach 80 kilometers). The basin area is 560,000 square kilometers, with more than 336 rivers flowing into it.

And it is also the deepest lake in the world, with a maximum depth of 1634-1741 meters and an average depth of 758 meters. Because of its deep depth, the water volume of Lake Baikal reaches 23.6 trillion cubic meters, accounting for 17% to 20% of the global freshwater resources, more than 8 times the total freshwater in China, and more than the entire Great Lakes of North America (22.56 trillion cubic meters). more water.

Since the water volume of Lake Baikal is so large and the water quality is good enough to drink directly, then, if other factors are not considered, is it feasible to introduce the lake water of Lake Baikal into China for use only from the technical point of view?

Can the "North-South Water Diversion" be realized?

Mongolia has thought about this issue. Because the climate is dry and cold for many years, even if it is warmer in the south, most of them are in desert and arid areas, which are not suitable for living. Therefore, the Mongolians have an idea of ​​"transferring water from the north to the south", transferring the fresh water resources of Lake Baikal to Inner Mongolia and even Inner Mongolia. It is the northern region of China, in order to meet the needs of domestic and industrial water.

Many people have high hopes for this idea, because there is only more than 2,000 kilometers from Lake Baikal to Beijing. If a transportation route is built, it will be connected to the Beijing-Hangzhou Grand Canal and flow south through the vast Mongolian Plateau. If possible, it will flow into the west, and it will also solve the problem of water management in the desert, so that the grasslands of Inner Mongolia can be basically maintained, and the problem of water shortage in the Beijing-Tianjin-Hebei region can be completely solved.

It's a good idea, but is it possible if you consider the technical aspects?

In fact, from a technical point of view, it is not difficult to transport the fresh water of Lake Baikal to China. If you want to allocate water resources across regions, of course, the first consideration is the issue of altitude. So what are the altitudes of Lake Baikal, Mongolia, and Beijing, China? We might as well learn from China's "South-to-North Water Transfer" project.

Lake Baikal is 456 meters above sea level, and the North China Plain, where Beijing is located, is 20-60 meters above sea level. Mongolia and China's Inner Mongolia share the Mongolian Plateau, with an average elevation of about 1,580 meters. That is to say, in order to realize the "North-South Water Transfer", one must first climb over the "big dirt bag" in the middle, which is more difficult than the South-to-North Water Transfer.

The South-to-North Water Diversion Project is divided into three routes: east, middle, and west, and terrain problems need to be overcome during this transportation process. China's terrain is high in the north and low in the south. The South-to-North Water Transfer Project is a counter-current to realize the idea of ​​water flowing to high places. The Yangtze River, Yellow River, Huai River and Haihe River are connected through three water transfer lines to form a national water supply network network.

For example, the East Route project, which was first started, draws water from the lower reaches of the Yangtze River, and uses the Beijing-Hangzhou Grand Canal and the rivers along the road to lift water step by step and transport it to the north. The method used is to use water pumps to pump water and transport the water to high altitude areas. It can be seen that it is not difficult to transport water from low to high.

Most of the conveying process adopts the method of open channel or aqueduct, so that the land along the way can be moistened during the conveying process, and the climate along the way will be improved to a certain extent with the arrival of the water source. Moreover, the cost is low, the engineering difficulty is small, and the maintenance work is relatively simple.

If the water of Lake Baikal is transported from Lake Baikal to the Mongolian Plateau by installing water pumps, and then flows naturally from Mongolia to China, it is not difficult for China today, but there is still one problem to be considered - the transportation The way is to choose an open channel or a pipe.

If you choose an open channel, a large part of the water resources will be consumed during the transportation. Because of the severe sandstorm in Mongolia, it has caused problems such as large-scale desertification, soil erosion and air pollution. The water quality sent in the process cannot be obtained. Assure.

However, if pipeline transportation is selected, the pipeline is prone to aging and rupture after a long time, and a series of problems such as repair and maintenance may occur. Moreover, because the topography of the two countries is quite different, pipeline transportation will increase the investment of project funds, prolong the construction period, and consume a lot of manpower and material resources.

Therefore, even if the technology is mature enough to make this idea a reality, the harsh surrounding environment will inevitably make the later cross-border maintenance a complicated problem. In addition to the need to invest a lot of money, various approval procedures will be extremely cumbersome and far away. There is no such thing as China's own South-to-North Water Diversion Project.

No matter how good the water resources of Lake Baikal are, we can just take a look. After all, China's South-to-North Water Diversion Project has now solved most of the water problems in the north.

Moreover, if the construction can really be carried out, then Lake Baikal will inevitably be polluted to a certain extent in the process, which will affect the living creatures in the lake and nearby, and affect the local ecological environment.

Because there are 1200 kinds of animals and more than 600 kinds of plants growing in the vicinity of the lake area, two-thirds of them are special creatures that are hardly found on the earth, and many other creatures have to go to places like a far-reaching tropical or subtropical tropics. found the same species or close relatives. For example, there is a kind of water daughter, which can only be seen in the southern lakes of China; there is also a kind of long-arm shrimp that can only be found in the lakes of North America.

However, what is most puzzling is that Lake Baikal, as a freshwater lake, is home to many creatures that should have lived in the ocean, such as seals, conch olmo fish, etc. And there are sponges that grow only in Baikal on the bottom of the lake.

Why is the fresh water of Lake Baikal able to survive so many marine life?

In response to this question, some scientists in the former Soviet Union speculated that during the Jurassic period of the Mesozoic Era, there was a Trans-Baikal Sea to the east of Lake Baikal, but due to the subsequent crustal movement, an inland lake, Lake Baikal, was left. With the continuous addition of rain and river water, the sea water has become thinner, and the marine animals in the lake are now left during that period.

This conclusion was later overturned, because with the improvement of drilling technology, scientists took core samples on the shore of Lake Baikal for inspection, but did not find sedimentary rocks in the Middle Ages, only Mesozoic sedimentary rocks, and other data show that the Baikal area has a long time. It has always been land, so the above conclusion is overturned.

Academicians of the former Soviet Union and some scientists believe that only seals and Omur fish are marine animals among the animals in Lake Baikal. symbols of.

This statement is still controversial, and the specific situation needs further research. But it is undeniable that Lake Baikal has survived from the Mesozoic to the present, with a history of about 30 million years.

What is the status of Lake Baikal?

Today, 30 million years later, Lake Baikal still maintains a good ecosystem. Although tourism has also been developed, in order to maintain the local ecology, the aborigines have been limiting the number of foreign tourists. Moreover, they opposed the construction of drinking water plants near Lake Baikal by Chinese companies before, so that the local construction of drinking water plants was permanently suspended.

Not only that, they also complained about the closure of a paper mill, the oil pipeline from Siberia to the Pacific Ocean died because of their opposition, and the hydropower plant built by Mongolia on the upper reaches of Lake Baikal, etc., all died without a hitch. They believe that it is their duty to protect Lake Baikal and do not allow anyone to destroy it because Lake Baikal has suffered damage in the past.

During the Soviet period, the local forests were cut down on a large scale, and a large amount of sewage was discharged into Lake Baikal. The ecosystem around the lake was disordered, and the seals and many aquatic organisms in the lake decreased sharply. Finally, Russia formulated relevant laws. The situation was alleviated.