A large area of cooling in the northern region has brought about the Inner Mongolia section of the Yellow RiverSpectacle of Liuling, ice flowers dotted on the surface of the river, such a beautiful scene made the water conservancy departments along the line nervous. So how did the liuling come about, and why did it make the water conservancy department nervous?
Liuling is a unique winter landscape of the northern rivers, becauseThe drop in temperature makes the river flow from the ice, mainly before the rivers are frozen and unsealed. Take the Yellow River, for example, the entire basin is locatedBetween 32° and 42° north latitude, the difference between north and south10 degrees of latitudeBecause of this, the temperature difference between the north and south sections of the Yellow River is obvious, resulting in the staggered time of freezing and thawing.
For example, the area where the Yellow River first appeared this year was the Ningxia section, which appeared on December 17, and the length of the liuling was35 km, the density is10% to 20%.But if the temperature rises, the thickness and area of the melted lings will become largerIt will accumulate in the narrow embankment, exerting excessive pressure on the embankment, which will cause the river to rise and form flooding
In addition, Lingxun is also divided into:Ice plugswithIce damsBoth cases. Ice plugsYesIt is formed by the accumulation of ice flowers and a large number of small broken ice in the river channel, which narrows the surface of the river and raises the water level of the ice-jammed river section and the upper reaches, withThe flood peak is small, the volume is small, the range is small, and the duration is longand other features.
WhileIce damsYesBy the accumulation of a large number of drift ice blocks, squeezing and blocking the river channel, a huge ice accumulation will be formed, resulting in the flow capacity of the river channel will be reduced or even zero, once formed, it will cause a large water level difference between the upstream and downstream, and eventually lead to the flood of Lingxun, withLarge range, large peak height, long durationcharacteristics, which can cause serious disasters.
Then we all know that the lower reaches of the Yellow River are also known as yesHanging river on the groundIf a large amount of flood water flows downstream, it may cause the water level of the Yellow River to rise sharply, thus crossing the river embankment and endangering people's lives and propertyIt is not difficult to understand why the water conservancy departments along the route are nervous. In the face of such a serious situation, how did our country prevent and solve it?
As the saying goes: it is easy to grab the flood, but it is difficult to prevent the flood. So every year the water conservancy department will be in timeMonitor the changes in the river sectionand will alsoCarry out the inspection and defense of embankments, pontoon bridges and construction trestle dismantling, etc, When the temperature is ** in the spring of the following year, the river surface begins to thaw, that is, the opening period of the river, which is dividedWenkai RiverwithWukai River
Wenkai RiverThat's itThe upstream and downstream rivers melt synchronously, and there is almost no danger of flooding；WhileWukai RiverIt's more serious, it's generallyThe temperature in the upper reaches of the river rises quickly, and the ice begins to melt, but the downstream river has not had time to thaw before the ice is broken by the impact of a large amount of river water upstream, which leads to the occurrence of flooding.
As soon as there is a Wukai River, we will adopt itManual intervention allows the river to open downstream, for exampleBombers dropped iron bombs to blow up the ice in the downstream section of the river and force the river to open。On April 5, 2023, the Mohe section of Heilongjiang was adoptedExplosives blasting, the river surface instantly stirred up dozens of meters high icefall, very spectacular. Today, the Yellow River still passesDiversion into the sand projectThe Lingshui in the flood season is brought to the hinterland of the Kubuqi Desert, which not only prevents the Yellow River from flooding, but also improves the ecological environment of the desert, truly achieving a win-win situation.
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