Drought in the middle and lower reaches of the Yangtze River: Some people accuse that "the Three Gorges Project itself is the cause of drought". Why? Reason.

Since the beginning of this year, the middle and lower reaches of the Yangtze River have suffered a rare drought. Although the Three Gorges Reservoir continues to "release water" to support drought relief, there are many arguments accusing the Three Gorges Project itself of causing drought, which once again pushes the Three Gorges Project to the forefront of public opinion.

On June 3rd, China Academy of Sciences held a media forum on the scientific view of climate and hydropower development. Wang Guangqian, an academician of China Academy of Sciences and director of the State Key Laboratory of Water and Sediment Science and Water Conservancy and Hydropower Engineering in Tsinghua University, told Nanfang Daily that the Three Gorges Project has nothing to do with drought, because it doesn't rain.

When many remarks pointed out that the Three Gorges Project changed the climate environment of the Yangtze River basin, resulting in "water storage in dry season and flood discharge in wet season", Academician Wang Guangqian said that although the Three Gorges Project has advantages and disadvantages, the advantages far outweigh the disadvantages.

"This is just a dam built in the river."

The dam is about 2 kilometers long and 185 meters high. When there is no dam, the water level is about 60 meters.

What do people think of when they mention the Three Gorges Project? Academician Wang Guangqian pointed out that to understand the Three Gorges Project, a comprehensive water conservancy project, we must understand "What is it? What did you bring? " He said that the Three Gorges Project has brought at least four major benefits: flood control, shipping, power generation and water transfer.

For the definition of the Three Gorges Project, Wang Guangqian has a very simple description: "It is a dam built in a river."

The dam is about 2 kilometers long and 185 meters high. When there was no Three Gorges Dam, the water level was about 60 meters, and the normal water level after elevation was 175 meters. The water level in summer is 1 45m, forming a river with a width of1km and a length of 600km, with a storage capacity of 39.3 billion cubic meters.

Due to the serious flood disaster in the Yangtze River, the most important function of the Three Gorges Project is flood control.

"The Yangtze River 1840 calculates the flood flow as 1 16000 cubic meters per second. If such a flood will sweep across the plain south of the Yangtze River, and the flood in 1998 will reach 60,000 cubic meters per second, then we should take precautions at that time. " Wang Guangqian analyzed that with the Three Gorges Project, there is not much problem in resisting the once-in-a-century flood.

"If the Three Gorges Project can be used in 1998, then many people will not die. Last year, the flood was 70,000 tons, more than 1.998. Because the flood is stored in the Three Gorges Reservoir, there is no problem. " Wang Guangqian said.

The second benefit brought by the Three Gorges Project is shipping. "It used to be a boat sailing on the Yangtze River, and people pulled the boat naked where they couldn't pass. I remember that one year I had to transport 30 tons of equipment from Wuhan to Chongqing via Yichang, which cost a lot of money. It used to take only one month to arrive, but now it can be delivered in one night. " Wang Guangqian said that in the case of high logistics cost, the benefits brought by the Three Gorges Project are greater than people think.

"The third benefit is to generate electricity and support the development of the national economy. In addition, in terms of water resources utilization, water can be transferred from Danjiangkou. " Wang Guangqian said.

Four Disadvantages and the First Harm of Three Gorges' Impact on Ecology

The living environment has not improved and there is no hope of getting rid of poverty. The impact is not a matter of two or three days

When talking about the negative impact of the Three Gorges Project, Wang Guangqian first thought of 6,543,800+300,000 immigrants.

"In order to ensure the construction of the Three Gorges Project, engineering resettlement is necessary. However, as far as the relationship between project immigrants and demolition immigrants is concerned, most of our country has not handled it well. If I am allowed to score, I should fail. " Wang Guangqian told reporters that some Three Gorges migrants have moved away, but many people are unwilling to leave their homes. There are too many people who need to be resettled, so they can only be placed on the top of the mountain, where it is steep and geological disasters are also a problem. The living environment has not improved and there is no hope of getting rid of poverty. The impact is not a matter of two or three days.

"The second is the ecological environment, and the most direct impact is the rare fish. I read a piece of information that a fish is ready to lay eggs when the water temperature is 18℃, and the laid eggs will be washed away by running water. If the reservoir is flooded at this time, the eggs will fall to the bottom of the reservoir and die. " Wang Guangqian said that the original design and planning of the Three Gorges Project did not consider the ecological function. Twenty years ago, the concept of ecological environmental protection was almost zero, and the importance of ecological function was gradually realized more than ten years ago.

In addition, after the completion of the Three Gorges Dam, the flood summit will bring sediment erosion, which will also have a certain impact on the ecological environment.

"The fourth problem is geological disasters. Because the water level of the Three Gorges Reservoir rises and falls rapidly, and this place was originally a geological disaster-prone area with many landslides. If the dam is soaked again, it will easily collapse. " Wang Guangqian told reporters that the Three Gorges Project will trigger a low-magnitude earthquake. After the completion of the project, the number of earthquakes has increased a lot, and the maximum magnitude is 6.4.

In fact, as early as April 2007, the Yangtze River Water Conservancy Commission of China Academy of Sciences issued the Report on the Protection and Development of the Yangtze River. The report shows that since the impoundment of the Three Gorges Reservoir in 2003, the frequency of microseismic activities in the Three Gorges area has increased significantly, and bank collapse and local slip will endanger the safety of some residential areas. According to statistics, there are 47 19 landslides in the reservoir area, of which 627 are affected by reservoir impoundment and 863 are resettlement areas.

The Three Gorges Project only affected the local climate.

The Three Gorges has nothing to do with drought, because it doesn't rain. This drought must be a natural disaster.

"I can clearly say that the advantages of the Three Gorges Project far outweigh the disadvantages. The Three Gorges has nothing to do with drought, because it doesn't rain. This drought must be a natural disaster. " Despite Wang Guangqian's words about hit the floor, there are still many questions about "fighting floods in previous years and fighting drought this year".

A few days ago, the Ministry of Environmental Protection responded to the question of the Three Gorges Dam at the press conference of the State Council Office, saying that the continuous lack of rain was the main cause of the drought.

Wang Donghai, executive deputy director of the Key Laboratory of Severe Weather of China Academy of Meteorological Sciences, said that drought is related to the balance of water system and an energy problem, and less precipitation does not mean drought.

"Drought is a natural normal. In the context of global warming, the weather and climate may change. Just like there are many tornadoes in the United States in spring, are more than 1000 tornadoes caused by Americans burning too much gasoline? People don't think so. Man-made reasons cannot be said to have no impact, but the impact is very small. "