How are sandstorms caused (in detail)

Questions and answers about sandstorm knowledge

Sandstorm is a natural phenomenon. In recent years, it has intensified, and human factors are not excluded. Nomadic culture has been ruthlessly replaced, which is the fundamental reason why sandstorms are more and more harmful. The biggest victims are also grassland nomads and a large number of immigrants.

1, Q: What is a sandstorm?

A: Don't call the general dusty weather a sandstorm. When the wind blows enough dust into the sky and the air visibility reaches a certain level, it can be called a sandstorm. Sandstorms usually rarely occur.

2. Q: Is sandstorm unique to China?

A: Sandstorm is a global climate phenomenon. Mainly occurs in windy and dry areas. Such as Central Asia, arid areas of North America, Australia, North Africa and other places. The sandstorm in China belongs to the arid area of Central Asia. Include Central Asia, Mongolia and northwest China.

3. Q: Did the sandstorm only appear in recent years?

A: Sandstorms have existed since ancient times. The recorded sandstorms in China can be traced back to the Han Dynasty. In fact, it has a history of at least millions of years on earth. For example, tens of thousands of years ago, there was a period of desertification in the Dalinuoer area of Chifeng City. 35,000 years ago, the lake reached its lowest point, flying sand and stones, forming a desert.

4. Q: Is the sandstorm more serious in China?

A: China's sandstorm covers a large area, and there is often more than one dust source on the dust road site. If several sources appear at the same time and accelerate gradually, a large area of strong sandstorm may be formed. For example, the one in April this year was the strongest in China this year. However, compared with the US 1934 sandstorm, we are still willing to give up.

5. Q: Sandstorms in China affected Beijing and North China, and drifted to South Korea and Japan. Some people say it's also in America, right?

A: First of all, it should be explained that the most harmful area of sandstorm is the arid area in the center of sandstorm, and sandstorm weather is global. Dust knows no boundaries, it floats into the sky and with the wind. The dust in Beijing does not necessarily come from the northwest of China, but from the local area, and may also come from Inner Mongolia, Mongolia and Kazakhstan. It's hard to say where the dust that floated to America came from.

6. Q: Some people say that sandstorms in China have eased in the past 50 years, right?

That's not entirely correct. In the last 50 years, due to some meteorological factors, it may be weaker than some of the strongest in history. However, the frequency of occurrence increased obviously and the degree of harm increased. Especially in recent 1 0 years, it has become an environmental problem that everyone pays attention to. Has endangered the normal life of hundreds of millions of people. Limited to studying the historical reality of sandstorms in China, I doubt the comparability of data provided by relevant departments.

7. Q: What are the causes of sandstorms?

A: There are many reasons for the formation of sandstorms. The driving force of sandstorm is wind. The material basis is dust. Wind and dust have complex and diverse temporal and spatial changes. There is strong enough wind and enough dust. But blowing a lot of dust also requires many conditions. A strong northwest wind prevails in the arid area of northwest China. Due to the uplift of the ancient Mediterranean, a large number of soft dust deposits were formed. Drought, little rain and sparse vegetation, especially in spring, drought, strong wind and sparse vegetation all occur at the same time, so there are natural conditions for sandstorms in spring, and human activities destroy the vegetation on the ground, making sandstorms worse and worse.

8. Q: Is environmental damage the direct cause of frequent sandstorms in China in recent years?

A: As I said just now, there are many causes of sandstorms. The high frequency of sandstorms in China in recent years is largely a response to the overall deterioration of the ecological environment in northern China, especially in arid areas, which is correct. For example, the recent strong sandstorm in Ejina Banner, Inner Mongolia, which first attracted everyone's attention, is directly related to the cut-off of Heihe River, the large-scale death of Populus euphratica and Haloxylon ammodendron. In Hailar City, Inner Mongolia, dust weather rarely appeared in the past, but due to the large-scale land reclamation in the west this year, dust has become an important environmental problem in Hailar City. In recent years, sandstorms in grassland areas of China are not only high in frequency and intensity, but also cause the expansion of deserts and even form new deserts. This is directly related to the comprehensive destruction of grassland, which ecologists have long expected.

9. Q: Is desert the source of sandstorm?

A: The desert is not so much the result of sandstorm as the existing desert and sand are involved in the formation of sandstorm. Because the main particles in dusty weather, especially the dust flying to high altitude and affecting Beijing and other places, are not large particles of dust, but fine particles of soil, and dust only has a greater impact on the local area. Fine soil is constantly blown away, and the rest gradually becomes a desert.

10, q: where does the dust that affects Beijing and North China mainly come from?

A: As I said before, sandstorms are international in scope. The dust that directly affects Beijing, North China and other places mainly comes from grasslands and desert areas near the north. It often starts from the desert areas of Central Asia and southern Mongolia, and continues to accelerate through the grassland areas of the Mongolian Plateau, with a large number of sandstorms participating, eventually forming large-scale sandstorms affecting North China and other places. Therefore, the northern grassland area, especially the nearby Xilin Gol grassland, is the key area.

1 1, Q: So the deterioration of grassland environment in Inner Mongolia is the main cause of sandstorm weather in Beijing and North China?

A: To a great extent. This year, sandstorms frequently occurred after the large-scale accelerated destruction of grasslands in Inner Mongolia 10 years. On the basis of degraded grassland accounting for one third, the grassland in Inner Mongolia increased by 65438 0.8% in the 1990s compared with the 1980s. In 10, another 6,000 square kilometers of sandy land were added in Ximeng grassland. It is meaningless to count the area of degraded grassland at present. The area of cultivated land in Inner Mongolia has expanded to 65.438+0.9 billion mu, with an average per capita of more than 8 mu. The farming-pastoral ecotone is getting wider and wider, close to the border between China and Mongolia. Panicum miliaceum and the degraded grassland with a large proportion of cryptophytes are easily blown away in spring, while the farmland is completely exposed in spring. So it is easy to cause wind erosion.

12, q: what are the reasons for the large-scale degradation of grassland?

A: Grassland is a fragile ecosystem with low productivity, which can only be used lightly, and it is also a potential desertification area, so high livestock carrying capacity will inevitably lead to degradation and desertification. Compared with the 1980s, the available grassland in Inner Mongolia decreased by 8.28 million hectares in the 1990s. And the number of livestock has increased by 30 million. In 1950s, the grassland area owned by each sheep was 3.3 hectares, 0.87 hectares in 1980s and 0 .42 hectares in 1990s. With the decrease of grassland area and grass yield per unit grass, livestock will increase endlessly, and the grass yield will still deteriorate faster.

13, q: in the history of inner Mongolia grassland, there is an imagination that the livestock carrying capacity is too high, and some areas are even as high as now. Why is grassland degradation not so serious?

A: ungulates are important members of grassland ecosystem. Antelopes, wild horses and houma on the grassland conform to the laws of nature and migrate on a large scale with the seasons. Grassland animal husbandry has also been nomadic for a long time. Facts have proved that nomadism is the best form of grassland utilization and the guarantee of grassland prosperity forever. Genghis Khan conquered half the world by nomadic animal husbandry.

14, q: Now that we have entered the information age, how can we let Mongolian herders live a primitive nomadic life?

A: This is a very complicated question. Some people say that human life has changed from flowing to fixed. From nomadic animal husbandry to agriculture, it is moving towards industrialization and urbanization. In fact, human development should be diversified. The ancestors of the Mongols used to have fixed fishing and hunting, agriculture and fixed whole sheep animal husbandry, and only after they arrived in the prairie and implemented nomadic animal husbandry did they develop further. Many modern inventions of human beings are conducive to mobility, such as transportation, communication and computers, so it can also be said that human beings will move towards mobility. Nomadic is the most advanced way to make light use of grasslands. Nomadic animal husbandry is the carrier of nomadic culture, and nomadic culture is the treasure of China culture and world culture. Nomadic culture takes aquatic plants as the first and livestock as the second. It is the ecological culture of harmony between man and nature, and the highest realm pursued by contemporary human beings.

15, q: How do nomads resist the increasingly serious natural disasters?

A: Nomadic is not to resist disasters, but to avoid disasters, adapt to nature and swim to suitable places. After settling down, people's life is temporarily comfortable, but livestock is better at most in one season, and the other three seasons are disasters. The grass around us has degraded, and we have to walk a long way to eat the grass in the distance every day. A few years later, due to the end of the grassland, the house had to be abandoned and moved farther away. At present, artificial grass planting on grassland can not meet the needs of livestock, and settlement itself means disaster. The loss is not only the ecological environment, but also the disappearance of nomadic culture. The settlement demonstration sites we set up in pastoral areas are a way to spend huge sums of money to sacrifice the ecological environment and turn swans into ducks.

16, q: when did the comprehensive improvement of grasslands in inner Mongolia begin?

A: The history and development of settled agriculture in Inner Mongolia is no less than that in the mainland. For thousands of years, agriculture has only been attached to nomadic animal husbandry. Since the Qing Dynasty, due to the increase of immigrants, pure agricultural areas have appeared in southern Inner Mongolia, and the farming-pastoral ecotone has emerged since then. After liberation, the pastoral areas in Inner Mongolia implemented a special policy of no distinction, no war and no class division. After the commune, they are still nomads, but the scope is very small. In the 1980s and 1990s, Inner Mongolia fully contracted livestock and grass, and fixed the right to use grasslands to households, ending the history of grassland nomadism.

17, Q: How did the cultivated land in Inner Mongolia increase?

A: Inner Mongolia has had agriculture since ancient times, and it has long been only a subsidiary industry of animal husbandry. There was large-scale agriculture in the Han dynasty, but a large number of land reclamation began in the Qing dynasty. After liberation, the population increased greatly, and animal husbandry alone could not support so many people. If more Han people enter Inner Mongolia, they will naturally engage in their familiar occupations.

18, q: it seems that population is the key. Isn't the population of Inner Mongolia large now?

A: At present, the total population of Inner Mongolia is 23 million, with 20 people per square kilometer. It is much less than Hebei and Shandong, but the latter belongs to warm temperate humid areas. Inner Mongolia is basically an arid area, with 0.5 people per square kilometer in Mongolia, 6.3 people in Kazakhstan and 0/0 people in Xinjiang. Some people say that the largest population in arid areas is 7 people per square kilometer, so there are at least 8.85 million more people in Inner Mongolia, more than three times. At present, millions of people in Ejina Banner, Wumeng, Yimeng, Ximeng and southern Zhejiang in Inner Mongolia have become or will soon become ecological refugees. Therefore, the population pressure in Inner Mongolia is not lower than that in other densely populated provinces and cities in China. In addition, because the migrant population is mainly bankrupt farmers with low education level, their overall quality is not high, and they can only carry out low-level destructive development. Increased the burden on the grassland. The greater harm of the population problem is that nomadic people will die out faster with the entry of a large number of agricultural people. This is the root of the growing sandstorm. In this sense, sinicization is desertification.

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