Baikal

Lake Baikal is the largest freshwater lake in Asia and the seventh largest lake in the world. The lake water is clear and of high quality, which can be drunk directly, and there is no need to worry about pathogens in the water, because the amphipod shrimp, a specialty of Lake Baikal, can filter the lake water at a depth of 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 place can reach 80 kilometers). The basin covers an area of ​​560,000 square kilometers, and more than 336 rivers flow into it.

Moreover, it is also the deepest lake in the world, with a maximum water depth of 1634-1741 meters and an average depth of 758 meters. Because of its deep depth, the water volume of Lake Baikal has reached 23.6 trillion cubic meters, accounting for 17% to 20% of global freshwater resources, more than eight 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 so good that it can be directly drunk, then, if no other factors are considered, is it feasible to introduce the water of Lake Baikal into China for use only from the technical level?

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

Mongolia once thought about this issue. Because the climate is dry and cold all year round, even if it is warmer in the south, most of them are in the arid desert area, which is not suitable for living. Therefore, the Mongolians have an idea of ​​​​"diverting water from the north to the south" to transfer the fresh water resources of Lake Baikal to Inner Mongolia or even It is the northern part of China to meet domestic and industrial water needs.

Many people have high hopes for this idea, because it is only more than 2,000 kilometers from Lake Baikal to Beijing. If the 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 to the west, and it will also solve the problem of water management in the desert, basically maintain the grasslands of Inner Mongolia, and completely solve the water shortage problem in Beijing, Tianjin and Hebei, and then go south to Xinjiang to turn Junggar and the Tarim Basin into oases.

Although the idea is better, is it possible if we consider the technical aspects?

In fact, from a technical point of view, it is not difficult to transport fresh water from Lake Baikal to China. If you want to allocate water resources across regions, the first consideration is of course the 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 Diversion" project.

The surface of Lake Baikal is 456 meters above sea level, and the North China Plain where Beijing is located is 20-60 meters above sea level. The two places are 1,500 kilometers apart, with Mongolia in the middle. Mongolia and China's Inner Mongolia are both located on the Mongolian Plateau, with an average altitude of about 1,580 meters. In other words, if you want to realize the "North-to-South Water Diversion", you must first climb through the "big soil bag" in the middle, which is more difficult than the South-to-North Water Diversion.

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, and the south-to-north water diversion project is to go upstream against the current and realize the idea of ​​water flowing to higher places. The Yangtze River, the Yellow River, the Huaihe River and the Haihe River are connected through three water diversion lines to form a national water supply line network.

For example, the Eastern Route project, which was first started, draws water from the lower reaches of the Yangtze River, uses the Beijing-Hangzhou Grand Canal and the rivers along the road to lift water step by step and transports it to the north, and passes through the lakes along the way to play a role in regulating and storing, and transports it to Yantai and Weihai. 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 a low place to a high place.

During the transportation process, most of them use open channels or aqueducts, so that the land along the way can be moistened during the transportation process, and the climate along the way will be improved to a certain extent with the arrival of water sources. Moreover, the cost is low, the engineering difficulty is small, and the maintenance work is relatively simple.

If the water from 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 now, but there is another problem that needs to be considered-the transportation The way is to choose open channel or pipeline.

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

However, if you choose pipeline transportation, the pipeline will be prone to aging and cracking after a long time, and a series of problems such as repair and maintenance may occur. Moreover, because of the large differences in terrain between the two countries, 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 turn this idea into reality, the harsh surrounding environment will inevitably make the later cross-border maintenance a complicated problem. In addition to requiring a large amount of investment, various approval procedures will be extremely cumbersome Not as cost-effective as China's own South-to-North Water Diversion Project.

No matter how good the water resources of Lake Baikal are, we can just look at them. 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 is really possible, Lake Baikal will inevitably be polluted to a certain extent during the process, which will affect the living organisms in and around the lake and affect the local ecological environment.

Because there are 1,200 kinds of animals and more than 600 kinds of plants growing around the lake area, two-thirds of which are special creatures that are hardly found on the earth, and there are still many creatures that can only be found in far-reaching tropical or subtropical places. Find the same species or close relatives. For example, there is a kind of water daughter-in-law, which can only be seen in lakes in the south of China; there is also a kind of long-armed shrimp that can only be seen in lakes in North America.

However, the most puzzling thing is that as a freshwater lake, Lake Baikal is home to many creatures that should have lived in the ocean, such as seals, conch olmu and so on. And there are also sponges that grow only in Lake Baikal on the bottom of the lake.

Why can so many marine life live in the fresh water of Lake Baikal?

In response to this question, some scientists from the former Soviet Union speculated that during the Jurassic period of the Mesozoic Era, there was a Transbaikal Sea to the east of Lake Baikal, but due to the subsequent crustal movement, an inland lake, Lake Baikal, was left behind. With the continuous addition of rainwater and river water, the sea water became thinner, and the marine animals in the lake are 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 from the Middle Ages, only Mesozoic sedimentary rocks. It has always been land, so the above conclusion has been overturned.

Academicians of the former Soviet Union and some scientists believe that among the animals in Lake Baikal, only seals and Omur fish are marine animals. Other creatures may be because Lake Baikal has conditions similar to the ocean, so the animals gradually developed similar to marine animals. symbols of.

This statement is still controversial, and the specific situation remains to be further studied. But it is undeniable that Lake Baikal has survived from the Mesozoic Era to the present, and it has 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 by Chinese companies near Lake Baikal before, so that the local drinking water plants were permanently suspended.

Not only that, they also complained that a paper mill was closed, the oil pipeline from Siberia to the Pacific Ocean also died because of their opposition, and the hydropower plant built by Mongolia on the upper reaches of Lake Baikal, etc., all ended without a problem under their stop. They believe that it is their responsibility to protect Lake Baikal and not allow anyone to destroy it, because Lake Baikal has suffered damage before.

During the Soviet period, the local forests were cut down on a large scale, 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 were drastically reduced. In the end, Russia formulated relevant laws. The situation was alleviated.