Geographical survey of the Yellow River

Geographical survey and prospect forecast of the Yellow River

The Yellow River is the second longest river in China. Originated in the Moon Valley at the northern foot of Bayankala in Qinghai Plateau.

Zonglie Basin winds eastward, crosses the Loess Plateau and Huanghuaihai Plain, and flows into Bohai Sea.

Sea. The total length of the main stream is 5464 kilometers, and the water level drop is 4480 meters. The total basin area is 795,000.

Square kilometers (including the inflow area of 42,000 square kilometers).

The Yellow River basin starts from Bayan Kara in the west, reaches Yinshan Mountain in the north, Qinling Mountain in the south and Bohai Sea in the east.

The inland potential in the basin is high in the west and low in the east, with great height difference, forming from west to east and from high to low.

Ladder. The highest step is the Qinghai Plateau where the source area of the Yellow River is located.

The famous "roof of the world"-the northeast of Qinghai-Tibet Plateau, with an average elevation of 4,000 meters.

In fact, a series of northwest-southeast mountains stand, such as Qilian Mountain in the north and south.

Anima Castle Peak and Bayan Kara in the Ministry. The Yellow River twists and turns between mountains and plains in an "S" shape.

A big bend. The mountains on both sides of the valley are 5500 ~ 6000 meters above sea level, and the relative height difference can reach.

1500 ~ 2000m. Daily elevation of Maqinggang, the main peak of Qingshan Mountain in Anima on the left bank of the Yellow River.

6282 meters, the highest point in the Yellow River Basin, is covered with snow all year round, and the ice peaks fluctuate.

Thousands.

The sunshine conditions in the Yellow River basin are relatively adequate in the whole country, with sunshine all year round.

Hours are generally 2000 ~ 3300 hours; The annual sunshine percentage is mostly 50% ~ 75%.

Between; The sunshine is the most abundant, second only to the Qaidam Basin, but it exceeds the Yangtze River south of the Yellow River.

The vast area of the river basin is generally about 1 times.

The total solar radiation in the Yellow River basin is in the middle of the country, north of 37 north latitude.

East longitude 103o west area and plateau area, namely 130 ~ 160kcal/cm2?

Year; Most of the rest areas are 1 10 ~ 130 kcal/cm2? Years, although not as good as.

The southwest of China, especially the Qinghai-Tibet Plateau, is strong, but generally exceeds the northeast and

The area south of the Yellow River is a strong radiation area in eastern China.

The flood in the lower reaches of the Yellow River mainly comes from the third section of the middle reaches, namely Hekou Town to Longmen.

(referred to as Long Jian); Longmen to Sanmenxia (referred to as dragon three); From Sanmenxia to

Huayuankou Room (referred to as Sanhuajian). The floods generated in these three periods constitute the downstream floods.

Water body. The floods in the above three different source areas constitute three types of Huayuankou Station.

The same type of flood: First, the water from He Long River and Longsanjian River above Sanmenxia is the main source.

The formation of a flood (called a flood). Such as the flood of 1933, and the measured flood of Shanxian Station.

The peak flow is 22,000 cubic meters per second; 1843 flood, according to the investigation, it is estimated that the flood of this station is within the territory of Shaanxi county.

The peak flow rate is 36,000 cubic meters per second. This kind of flood has the characteristics of high peak, large volume and large sediment concentration.

Big features, a serious threat to downstream flood control. The second is the water from the following three flowers in Sanmenxia.

Mainly (called the next big flood). For example, the measured peak flow at Huayuankou Station in 1958 is 22,300 cubic meters.

M2/sec, investigation flood 176 1 Huayuankou Station 32,000m3/sec. such

Flood has the characteristics of fierce rising, high flood peak, low sediment concentration and short forecast period, which is harmful to the Yellow River.

Flood control downstream is the biggest threat. Third, dragon three Room above Sanmenxia and below Sanmenxia.

Three flowers are made up of the same water (called flood). For example, 1957, 1964.

In the annual flood, the discharge of Huayuankou Station was13000m3/s and 9430m3/s respectively.

Second, it is characterized by low flood peak, but it lasts for a long time, and the threat to the downstream dike is also quite great.

Seriously.

For a long time, the flood disaster in the lower reaches of the Yellow River is particularly serious, not only because of the flood.

What is more important is that the river is silted up, the river bed continues to rise, and the flood discharge capacity is reduced.

Low. The average sediment transport in the lower Yellow River for many years is 65.438+0.6 billion tons, and about 400 million tons of sediment is deposited every year.

Accumulated in the downstream channel, the riverbed is raised day by day, making it generally higher than the ground on both banks.

3~5 meters, the highest is 10 meter, making it a world-famous "hanging river on the ground".

There is always the danger of overflow or rupture. The peak flow of Shan County Station 1933 is 22,000m3 per meter.

Second flood, water and sand, siltation, water level is extremely high. As soon as the flood comes out of the canyon, it is from

From Wenxian and Wuzhi to Lankao and Changyuan, the dikes on both sides of the strait burst at 6 1, and many of them were floods.

Overflow the top of the dike and be in flight. Due to sediment deposition, the riverbed is wide and shallow, and there are many slips.

Change, once the big sliding roof rushes to the levee, it often happens. After the Yellow River burst, we waited for a long time.

Can not be blocked, that is, the formation of river migration and diversion.

River regulation is to prevent and control water disasters, build water conservancy projects and control and guide water flow.

Measures to stabilize flowing potential. Harnessing the Yellow River has a long history. Because of the calendars on both sides of the river

The future is a place where human beings thrive, so there have been some rectifications since ancient times.

River measures. According to legend, more than 2,300 years ago BC, Dayu used the nature of water,

By dredging the situation, dredging the river and guiding the stagnant flow, the overflow flood will be discharged into the sea. Western Han Dynasty (206 BC-25AD)

On the Yellow River around Xunxian County, a stone dike was built at the bend where the water was seriously washed away.

Flow to prevent bursting. During the Eastern Han Dynasty, the "Baji Dike" was built in Yuanyang area, namely

Build a stone crib with stones in the dike section with serious sliding brush and move it outward, which is similar to the present situation.

Dams and piles for emergency workers. On the basis of many years' practice of river management in Ming Dynasty, Pan Jixun put forward

"If the water is slow, the sand will stop, and if the sand stops, the river will be full", "Hydration is fierce,

The potential is fierce, and the sand brush is deep in the river. "scientific conclusions about the relationship between water and sediment, and mention.

Get out of the stable river, build dikes, control water and attack sand, and brush the Yellow River with clean water.

Policy. He advocated the establishment of a dike system consisting of continuous dikes, remote dikes, moon dikes and lattice dikes.

Under the conditions at that time, all these have high scientific value and practical significance.

The river management measures adopted in past dynasties have played an important role in flood control.

Since the founding of New China, the traditional management mode of the Yellow River in China can be summarized as follows:

The management of the Yellow River mainly focuses on human safety and economy; In the management measures, we mainly focus on

Yu water conservancy project; In water conservancy projects, we mainly pay attention to dam and reservoir construction. This model

Although it has its historical rationality. However, according to the current water resources and health status of the Yellow River and its basins.

National, economic and social conditions, according to the modern demand for the Yellow River, according to the above ethics

Frame, the shortcomings of this traditional model are: first, it ignores the Yellow River.

State, Yellow River culture; Second, due to the emphasis on engineering, the contempt for the system, and the emphasis on dams and reservoirs,

Ignore other engineering measures (such as water distribution and environmental protection). ), so it is not more effective.

Improve the quality and utilization efficiency of water resources, expand the service function of water resources and improve water.

Fairness of economic income distribution.

In order to achieve the ultimate goal of healthy living in the Yellow River, the Yellow River Water Resources Commission will

We should start from the following aspects: promoting the construction of sediment reduction measures; Effective management process

Utilization of water resources in regions and related areas; The water diversion party in the outer basin increases the water resources of the Yellow River

Case study; Establish a water and sediment regulation system for the Yellow River; The planning of the lower reaches of the Yellow River is scientific and reasonable.

Governance strategy; Water quantity and its process ensure that the main channel of the downstream river will not shrink.

Shaping; Meet the requirements of reducing the ratio of pollution to diameter; Harnessing the Yellow River estuary.

With the rapid economic development of the Yellow River basin, the expansion of urban population, wastewater

Emissions are increasing day by day. According to statistics, at the end of 1970s, the annual wastewater discharge was 6543.8+0.85 billion.

Tons, 21.70 billion tons in the early 1980s and 3.26 billion tons in the early 1990s, with a period of 10 year.

Increase by more than 50%. Among them, industrial wastewater is 2.33 billion tons, accounting for the total wastewater in the basin.

7 1.5%, domestic sewage 930 million tons, accounting for 28.5%. From 1993 Yellow River Water Resources

The water conservancy departments of all provinces and autonomous regions in the basin organized the investigation results of the water source protection bureau on the sewage outlets entering the river.

You see, the main stream of the Yellow River is under Longyangxia Reservoir, and part of it flows through cities and industrial and mining areas.

The main tributary, the sewage outlet that discharges more than 5,000 tons of wastewater every day, reaches more than 1.500.

Among them, nearly 150 is directly discharged into the main stream of the Yellow River, accounting for about 10%. Scope of investigation only

The domestic sewage and waste sewage flowing into this river every year has reached nearly 3.2 billion tons. Therefore, at present, the whole basin is polluted by waste.

The actual annual emissions are much higher than the statistical value of 3.26 billion tons.

The disparity in temperature difference is a major feature of the climate in the Yellow River Basin. Generally speaking, with the terrain level 3.

Ladder, from west to east, from cold to warm, the east-west gradient of temperature is obviously greater than the north-south gradient.

Gradient. The lowest center of the annual average temperature of about -4℃ is located in Bayankala, Heyuan.

At the northern foot of the river, the extreme minimum temperature in the basin appeared at the station along the Yellow River in the source area, and there was once-

Records at 53.0℃ (1978 1.2). The annual average temperature is 12~ 14℃.

This area is located in Shandong Province in the lower reaches of the Yellow River, and the extreme maximum temperature has been recorded in the basin.

At Yichuan Station in Luoyang, Henan Province, its value reached 44.2℃ (1June 20, 996.

God).

The Weihe River, which originated in Gansu, is the largest tributary of the Yellow River, and the upstream pollution is serious.

After leaving Gansu, it flows through Shaanxi 18 counties and cities, and now it is in xi 'an, Baoji, Xianyang and Weihe.

Meanwhile, southern China and central cities in other provinces have received at least 300 million tons of industrial waste.

Water, in which chromium is 2 1.2 million tons, makes the Weihe River the most polluted in the Yellow River.

A tributary. The "veritable" main force that causes pollution is the paper industry. No.

Any environmental protection facilities, black liquor produced in pulping process and white liquor produced in bleaching process are

Directly discharged into the Weihe River. Although industrial pollution is still very serious, life along the Yellow River has been polluted.

Develop at a faster speed. Most towns in the basin don't.

Domestic sewage treatment facilities. At present, about 2 billion tons of sewage is discharged, only

8.8% was treated, and only 5.5% reached the standard. In the early 1980s, Huang

River water pollution mainly occurs in the dry season, and after entering the 1990s, in the wet season and

The pollution degree in dry season is similar, and the pollution in rainy season is obviously aggravated.

The pollution range extends from Lanzhou, Baotou and other old industrial bases to the middle and lower reaches, and is in the old pollution

While the source has not been effectively controlled, Tongguan, Shizuishan,

In Huayuankou and other reaches, the water quality has obviously deteriorated.

Perhaps there will be no busy sand dredgers in the future, and they will be replaced by advanced ones.

Filters, they can work day and night, collect a lot of sediment, and make the Yellow River clearer.

No matter how beautiful it is, if human beings are not vigilant or endlessly exploited, it will lead to malignancy.

The cycle is repeated, and the consequences are unimaginable.

I hope everyone will protect the Yellow River and make it more beautiful and brilliant!