The mountainous and grassland plateaus from Heyuan to Guide belong to the Qinghai-Tibet Plateau. The peaks are all above 3000 meters above sea level; The upper valley is over 4200 meters above sea level. The terrain on both sides of the upper valley is gentle and the drainage is not smooth; Causing large areas of swamps and many lakes. Guide's reach from Jinmeng River is the Loess Plateau, with Xibe and Weihe valleys in Lvliang in the south, Ordos Plateau in the north and Lanzhou Valley in the west. The elevation of the Loess Plateau is generally 1, 000- 1, 300m, with uneven landform and steep slope. The gully ground slope is 1.5-20 degrees, the gully area accounts for 40-50%, the gully density is 3-5km/km2, and the cutting depth exceeds/kloc-0. Below Jin Meng, it enters the low-lying North China Plain, with an altitude of no more than 50 meters. After entering the downstream, the river channel is flat, and the average gradient is only 0. 12%. The water flow slows down and a lot of sediment is deposited, which is 4-5 meters above the ground. Due to the repeated diversion of the Yellow River, the fan-shaped ancient riverbed and ancient natural dike have become inclined plains with alternating gentle hills and depressions, and the depressions are relatively open and flat.
River basin survey
The Yellow River reaches Hekou Town, Tuoketuo County, Inner Mongolia Autonomous Region, with a total length of 3,472 kilometers. The middle reaches are from Hekou Town to Taohuayu, Zhengzhou, Henan Province, with a river length of 1206 km. Below Taohuayu is the downstream, with a river length of 786 kilometers. There are many opinions on the division of the upper, middle and lower reaches of the Yellow River, and the division scheme of the Yellow River Water Resources Commission is adopted here. The Yellow River runs across China from east to west, with a length of 1.900 km from east to west and a width of1.654,38+0.000 km from north to south, with a total area of 752,443 square kilometers.
The Yellow River, like a lion with his head held high, crosses the mountains of Qinghai and Gansu provinces from the Qinghai-Tibet Plateau. Hetao Plain across Ningxia and Inner Mongolia; Pentium in the ravine between Shanxi and Shaanxi; Break through the "Longmen", turn around at the foot of Huashan Mountain in Xiyue, cross the North China Plain, and head for the coast of Bohai Sea. It flows through 9 provinces and autonomous regions and gathers more than 40 main tributaries and 1000 streams and rivers, with a journey of 5,464 kilometers and a drainage area of more than 750,000 square kilometers, making it the second largest river in China. The average annual precipitation in the whole basin is about 400 mm, while the average annual runoff of the Yellow River is only 57.4 billion cubic meters, ranking eighth among Chinese rivers. There are more than 200 million mu of cultivated land in the basin, and the population is about 654.38+0 billion along the Yulu River downstream.
The average natural runoff of the whole Yellow River for many years is 58 billion cubic meters, the average annual runoff depth of the basin is 77 mm, the per capita water volume of the basin is 593 cubic meters, and the cultivated land is 324 cubic meters.
The middle reaches of the Yellow River flow through the Loess Plateau, and tributaries bring a lot of sediment, making the Yellow River the largest river with sediment concentration in the world. The annual maximum sediment discharge is 3965438+ 1 100 million tons (1933), and the maximum sediment concentration is 920kg/m3( 1977). The average sediment discharge of Sanmenxia Station for many years is about 65.438+0.6 billion tons, and the average sediment concentration is 35 kg/m3.
branch
The main tributaries of the Yellow River are Baihe, Heihe, Huangshui, Zuli, Qingshui, Dahei, Kuye, Wuding, Fenhe, Weihe, Luohe, Qinhe and Dawenhe.
Major lakes
There are Zhaling Lake, Eling Lake, Wuliangsuhai Lake and Dongping Lake.
Mainstream canyon
There are 30 canyons in the main stream of the Yellow River, 28 in the upper reaches and 2 in the middle reaches. The lower reaches flow through the North China Plain without canyons. The canyon section of the main stream is 1707 km long, accounting for 3 1.2% of the total length of the main stream.
Upstream: From Heyuan to Guide, there are mountainous and grassland plateaus on both sides, with an altitude of over 3,000m and a peak of over 4,000m m.. The river course is S-shaped, and the river course twists and turns within 400 kilometers of the headwaters. There are many lakes, grasslands and swamps on both sides of the strait, and the clear water flow of rivers is stable, with less water consumption and large water production. There are many lakes, and the largest lakes, Xingsuhai and Eling Lake, have a cold plateau climate. Fish resources have not been exploited for a long time.
Mid-stream: Jin Meng tour guide, mostly passing through high mountains and canyons, with fast current and steep slope. The Liujiaxia Valley is extremely deep, with a river width of 50-70 meters, a narrowest point of less than 15 meters and a valley depth of 100-500 meters. The current is swift, narrow and steep, and it is rich in hydraulic resources. A large reservoir was built on the canyon. The Yellow River flows through Hekou Town, turns south, passes through Qin Jin Canyon, and reaches Longmen with a total length of only 7 18km, a drop of 6 1 1m, and a steep slope. From Longmen to Tongguan, the river reaches 130km, and the water flows in Nafen, Weihe, Zhu Jing and Luozhu rivers, with a large increase in water volume, serious sediment deposition and unstable river course.
Downstream: The section from Jinmeng to North China Plain is the downstream, with a total length of 874 kilometers. The river is wide and flat, with slow water flow and siltation. The riverbed is 4-5 meters above the ground on average. It is an aboveground river with the richest fish resources, including estuarine migratory fish, river fish, settled fish, brackish water fish and aquatic fish.
There are different opinions about the boundary between the upper, middle and lower reaches of the Yellow River. The Yellow River Conservancy Commission divides Hekou Town and Taohuayu into upper, middle and lower reaches. Traditional middle school textbooks divide Hekou Town and Jin Meng into upper, middle and lower reaches. Scholar Yang thinks Qingtongxia and Harmony are more suitable. Scholar Xu advocated Jiayingguan in Wuzhi County, Jiaozuo City, Henan Province as the dividing line between the middle and lower reaches of the Yellow River. The following is the division plan of the Yellow River Water Conservancy Commission.
Upstream
The upper reaches of the Yellow River are above Hekou Town, Tuoketuo County, Inner Mongolia. The total length of the upper reaches is 3,472 kilometers, and the basin area is 386,000 square kilometers, accounting for 5 1.3% of the total Yellow River. The total upstream drop is 3496m, with an average gradient of10 ‰; There are 43 large tributaries (basin area 1000 square kilometers or more), and the runoff accounts for 54% of the whole river; The upper reaches of the Yellow River only account for 8% of the annual sediment discharge of the whole river, with more water and less sediment, which is the clear water source of the Yellow River. The upper reaches of the river are controlled by Qingshan Mountain, Xiqiao Mountain and Nanshan Mountain in Anima, Qinghai, with an S-shaped bend. According to the different characteristics of rivers, the upper reaches of the Yellow River can be divided into three parts: source section, canyon section and alluvial plain section.
The upper part of Qinghai Kariqu to Qinghai Guide Longyangxia is the Heyuan section. Heyuan section starts from Kariqu, passes through Xingsuhai, Zhaling Lake and Eling Lake to Maduo, bypasses Qingshan and Xiqingshan in Anima, and reaches Guide in Qinghai via Longyangxia. Most of the rivers in this section flow through the plateau of three or four kilometers, and the rivers are tortuous, with lakes, swamps and grass beaches on both sides. The water quality is clear, the water flow is stable and the water yield is large. There are Zhaling Lake and Eling Lake in the reach, both above 4260 meters above sea level, with storage capacity of 4.7 billion cubic meters and 654.38+0.08 billion cubic meters respectively, which are the largest plateau freshwater lakes in China. The Yellow River runs from Maduo, Qinghai Province to Maqu, Gansu Province, and flows through the ancient basin and low hills between Bayankala and Animaqing Mountain. Most river sections have wide valleys, and occasionally there are canyons. The Yellow River runs from Maqu, Gansu Province to Longyangxia, Guide, Qinghai Province, and flows through high mountains and canyons, with fast-flowing water and abundant hydraulic resources. Baihe and Heihe rivers, tributaries originating in Minshan, Sichuan, join the Yellow River in this section.
The section from Longyangxia in Qinghai to Qingtongxia in Ningxia is a canyon section. This section of the river flows through mountainous hills. Due to different rock properties, river valleys and wide valleys appear alternately: river valleys are formed in hard gneiss, granite and Nanshan metamorphic rocks, while wide valleys are formed in loose sand shale and red rock series. There are 20 canyons in this section, including Longyang Gorge, Jishi Gorge, Liujiaxia Gorge, Bapan Gorge and Qingtongxia. There are cliffs on both sides of the canyon, with narrow riverbed, steep river slope and rapid water flow. From Guide to Lanzhou, this section is one of the concentrated reaches of the three major tributaries of the Yellow River, and the inflow of important tributaries such as Taohe River and Huangshui River has greatly increased the water volume of the Yellow River. The reach from Longyangxia to Xiaheyan River in Ningxia is a "mine-rich" area of the Yellow River and one of the important hydropower bases in China.
Qingtongxia in Ningxia to Hekou Town in Tuoketuo County, Inner Mongolia is an alluvial plain. After leaving Qingtongxia, the Yellow River flows northeast along the northwest boundary of Ordos Plateau, and then reaches Hekou Town eastward. Most of the areas along the river are deserts and desert grasslands, and there is basically no tributary injection. The river bed of the main stream is gentle and the water flow is slow. On both sides are large alluvial plains, namely the famous Yinchuan Plain and Hetao Plain. There are floods and ice disasters in the plain along the Yangtze River to varying degrees. Hetao Plain starts from Xiaheyan in Ningxia in the west and reaches Hekou Town in Inner Mongolia in the east, with a length of 900 kilometers and a width of 30-50 kilometers. It is a famous irrigation area for diverting water from the Yellow River with a long irrigation history. Since ancient times, there has been a saying that "the Yellow River is full of disasters and there is only one set of wealth".
middle reaches
The reach of the Yellow River between Hekou Town, Tuoketuo County, Inner Mongolia and Taohuayu, Zhengzhou, Henan Province is the middle reaches of the Yellow River, with a total length of 1.206 km and a drainage area of 344,000 square kilometers, accounting for 45.7% of the total drainage area. The total drop in the middle reaches is 890 meters, with an average gradient of 0.74 ‰; This river has 30 major tributaries; The increased water volume accounts for 42.5% of the Yellow River water volume, and the increased sediment volume accounts for 92% of the whole Yellow River sediment volume, which is the main source of the Yellow River sediment.
Hekou Town to Yumenkou is the longest continuous canyon on the main stream of the Yellow River-Shanxi Canyon. Most tributaries in the reach flow through the loess hilly and gully region, which is the main source of coarse sediment in the Yellow River, and the annual average sediment transport of the whole river is 900 million tons from this region. This reach is the second largest hydropower base of the Yellow River with large gradient and abundant hydraulic resources. There is a famous Hukou Waterfall in the lower part of the canyon, with a deep trough width of only 30-50 meters and a low water level drop of about 18 meters, which is magnificent.
From Yumenkou to Sanmenxia, the Yellow River flows through the Wei Fen Plain, the valley widens and the water flows slowly. On both sides of the reach are Weibei and Jinnan loess tablelands, which are important agricultural areas in Shaanxi and Shanxi provinces. This reach has accepted Fenhe River, Luohe River, Jinghe River, Weihe River, Luo Yi River, Qinhe River and other important tributaries, and is one of the main sources of sediment in the lower reaches of the Yellow River, with an average annual output of 550 million tons. The reach is located in the channel from Yumenkou to Tongguan (that is, the small north main stream of the Yellow River) 132.5km, with drastic changes in erosion and deposition, and the channel is very unstable from side to side. Constrained by the mountains near Tongguan, the valley suddenly narrows, forming a natural bayonet with a width of only 1000 meters. The level of Tongguan river bed is closely related to the changes of erosion and deposition in the Xiaobei main stream of the Yellow River and the lower reaches of the Weihe River, so the hydrological term "Tongguan elevation" is used.
Sanmenxia to Taohuayu section is divided into two parts from Xiaolangdi: above Xiaolangdi, the river is between Zhongtiao Mountain and hill, which is the last canyon on the main stream of the Yellow River; The valley below Xiaolangdi gradually widens, which is the transition section of the Yellow River from mountainous area to plain.
lower reaches
The Yellow River below Taohuayu in Zhengzhou, Henan Province is the lower reaches of the Yellow River, with a total length of 786 kilometers and a drainage area of only 23,000 square kilometers, accounting for 3% of the total drainage area. The total downstream drop is 93.6m, with an average gradient of 0.1.2 ‰; The increased water volume in the interval accounts for 3.5% of the water volume of the Yellow River. Due to the large amount of sediment in the Yellow River, the downstream reaches have been silted for a long time to form a world-famous "aboveground river", and the Yellow River has become a watershed between the Haihe River Basin and the Huaihe River Basin. Except for the Dawen River flowing from Dongping Lake, there are no big tributaries in this section.
Except for the low hills between Dongping Lake on the south bank and Jinan, the lower reaches depend on dikes, with a total length of 1.400 km. Historically, the lower reaches of the Yangtze River often burst, which brought heavy disasters to the Chinese nation. Because the lower reaches of the Yellow River flow from southwest to northeast, the north of the Yellow River freezes first in winter, forming ice flood. Ice dams are easily blocked by the overflow of ice, which leads to the overflow of dikes and poses a serious threat.
Below the downstream Lijin is the Yellow River estuary. Due to sediment deposition, the mouth of the Yellow River keeps extending and swinging. At present, the Yellow River estuary is located at the intersection of Bohai Bay and Laizhou Bay, which is a new channel formed by the siltation of Qingshuigou after the artificial diversion of 1976. In recent 40 years, the average sediment transported by the Yellow River to the estuary area is about 654.38+100 million tons/year, with an average annual net land of 25 to 30 square kilometers.
use
environmental protection
From 3000 BC to 2000 BC (Yangshao culture in the Yellow River valley to Yinxu in Anyang), the geographical environment of the Yellow River valley was suitable for the growth of vegetation and the development of human production and living activities, and the climate environment about 2℃ higher created favorable conditions for the development of crops and vegetation. During this period, there were a large number of lakes such as Leixiaze and Onoze in the middle and lower reaches of the Yellow River. "On Mencius Teng Wengong" once recorded that the Yellow River valley was "lush with plants and animals", and the Guanzhong Plain still had "beautiful mountains and rivers, criss-crossing rivers and numerous talents" until the Warring States period in China (the forest in the middle reaches of the Yellow River in historical period, Shi Nianhai, 198 1 year).
After the Warring States period, with the extensive use of iron farm tools and the migration of Qin's economic center to Guanzhong, the vegetation in the Yellow River basin and the Loess Plateau began to be destroyed. Because the Yellow River Basin has been the center of Chinese civilization for a long time (China Historical Geography, Lan Yong, 2002), and the phenomenon of emphasizing agriculture over grazing in ancient China, the vegetation destruction in the Yellow River Basin has become a long-term and large-scale phenomenon. With the beginning of the cold climate in 1 1 century and the southward movement of the economic center of China, the ecological damage in the Yellow River basin began to decrease, but the forest coverage rate has been difficult to recover to the situation of the 3rd century BC. With the destruction of vegetation, the Loess Plateau began to be eroded by the Yellow River, and a large amount of soil was swept away, forming a surface morphology of thousands of valleys. According to the research of scientists, the Yellow River has changed for two reasons. 1. Since the Qin Dynasty, the temperature in the Loess Plateau has turned cold and the rainstorm has been concentrated. Coupled with the loose structure of loess itself, it is easy to be eroded and collapsed, which encourages soil erosion and makes a lot of sediment enter the Yellow River. Second, the rapid population growth, unrestricted land reclamation and grazing, caused the destruction of forests, grasslands, green vegetation, and the loss of natural protective layer on the Loess Plateau, resulting in serious soil erosion. Every year, 4,000 tons of precious soil is eroded every square kilometer in the Yellow River Basin, which is equivalent to destroying 5.5 million mu of cultivated land a year! More seriously, soil erosion significantly reduces soil fertility, resulting in a large area of crop production reduction. The more production is reduced, the more people need to reclaim wasteland: the more land is reclaimed, the more serious soil erosion will be. In this way, the poorer the reclamation, the more sediment the Yellow River will have, and the number of breaches and diversions of the Yellow River will become more and more frequent. The key to harnessing the Yellow River is to control sediment and prevent it from flowing into the Yellow River at will. After the founding of New China, scientists designed a scheme to control the Yellow River. They believe that the Loess Plateau should adhere to the management direction of animal husbandry and forestry. We must protect forest resources and restore lost vegetation as soon as possible. Let everyone know that deforestation is downright self-destructive, and it is necessary to rationally plan and use land and build a large number of water conservancy projects. This multi-pronged approach will certainly prevent soil erosion and make the dream of the Yellow River better realized.
Block a river
Since 1972, the Yellow River has been frequently cut off. There are many reasons for disconnection, which can be summarized as follows:
1. Global warming. With the aggravation of global warming in recent years, on the one hand, the evaporation of rivers has greatly increased, on the other hand, the melting of glaciers in the upper reaches in spring and summer absorbs a lot of heat, which leads to the local temperature in the inland being lower than normal, which reduces the temperature difference between the inland and the ocean, which in turn leads to the weakening of the monsoon and the lack of water vapor brought into the inland by the monsoon from the sea surface. Although global warming makes glaciers melt and increases the flow of upstream water sources, it cannot offset the effects of increased evaporation and weakened monsoon. Eventually, the water volume in the middle and lower reaches will decrease year by year.
2. Vegetation destruction. The vegetation in the Loess Plateau is seriously damaged, and the land lacking vegetation conservation is gradually desertified, and the evaporation capacity is increasing. The dried-up groundwater needs to be continuously absorbed and replenished by flowing through rivers.
3. Backward irrigation methods. Most of the middle and upper reaches of the Yellow River flow through the economically underdeveloped border areas, lacking the technology and funds for water-saving irrigation, and most of them are flooded, resulting in serious waste of water resources in the Yellow River.
Valley migration
According to historical records, in the three or four thousand years before 1946, the Yellow River was threatened by the recent 1593 flood, and the river course was diverted 26 times due to the flood, and the river burst 1000 times.
The last diversion of the Yellow River was in 1855 (the fifth year of Qing Xianfeng). Before the great diversion of the Yellow River, the lower reaches of the Yellow River flowed through the route. According to China's current administrative divisions, it generally passes through Xingyang, Zhengzhou, Yuanyang, Fengqiu, Zhongmou, Kaifeng, Lankao and Puyang in Henan, Caoxian and Shanxian in Shandong, Dangshan and Xiaoxian in Anhui, and finally reaches Fengxian, Peixian, Xuzhou and Pixian in Jiangsu. However, after the diversion, the Yellow River broke through the original channel, changed to the northeast, and borrowed the Daqing River to flow into the Bohai Sea in Shandong.
Recently, the problem of weathering has become more and more serious. Now experts say that if human beings cut down trees indiscriminately, the source of the Yellow River is likely to be submerged in wind and sand. The Yellow River is the origin of the Chinese nation, but it is called the source of the mother river. Today, it is surrounded by barren hills and sandstorms everywhere.
Experts pointed out that illegal logging against the natural way of life is the main reason for destroying water resources, which makes this ecosystem with thousands of years of history face collapse and is likely to become another site of human civilization destruction.
waterfall
Because of sediment deposition, the 5464-kilometer-long bed of the Yellow River is higher than the cities and farmland in the basin, and it is constrained by dikes, otherwise it will bring disaster to the local people in the basin, so it is called "hanging river". So where did the Yellow River become a "hanging river"?
Dengkou County, southwest of Bayannur League, Mongolia, where the Yellow River is 4 to 6 meters higher than the county on average.
The Yellow River flows between Zhongtiaoshan Mountain and Qinling Mountains and passes through Jin Meng, Henan Province. From here, 30 kilometers away from the Yellow River, it is Luoyang, the famous capital of China. Luoyang is one of the eight ancient capitals in China. Since the Eastern Zhou Dynasty, the Eastern Han Dynasty, the Cao Wei Dynasty, the Western Jin Dynasty, the Northern Wei Dynasty, the Sui Dynasty (Yang Di), the Tang Dynasty (Wu Zetian), the Later Liang Dynasty and the Later Tang Dynasty have all established their capitals here, which is called the "Ancient Capital of Nine Dynasties".
After the Yin Dynasty was destroyed, Jiuding, the national treasure, moved to Luoyang with the intention of taking Luoyang as its capital. After the death of King Wu, Duke Zhou and Duke Zhao, who assisted the king at that time, built Luoyi on a large scale, and established two cities, namely, King City and Chengzhou City. Between Jianshui East and Shuixi is Wangcheng, which is today's Wangcheng Park in Luoyang, Henan Province. In Shuidong, near the White Horse Temple today, is Chengzhou City. Move the capital to Wangcheng, and move the capital to Zhoucheng in Zhou. After Liu Xiu proclaimed himself emperor in the Eastern Han Dynasty, Luoyang became the capital.
Luoyang City in Han and Wei Dynasties was expanded on the basis of the ruins of Chengzhou City. The history of Luoyang City is "90 steps from north to south and 60 steps from east to west", so it is also called "96 City".
As early as five or six thousand years ago, there was "Yangshao culture" 50 miles west of Luoyang, which shows that the matriarchal clan commune system was quite developed at that time. This is the beginning, more and more brilliant.
Li Bai said in his poem: Without looking at how the water of the Yellow River moves out of heaven, it rushes to the sea and never returns. The Yellow River originates from the Yogu Zonglie Basin at the northern foot of Bayankala in the Qinghai-Tibet Plateau at an altitude of 4,500 meters. It flows into the Bohai Sea through Qinghai, Sichuan and Gansu in the Qinghai-Tibet Plateau, Ningxia, Inner Mongolia, Shaanxi and Shanxi in the Loess Plateau and Henan and Shandong in the North China Plain, with a total length of 5,464 kilometers and a drainage area of 750,000 square kilometers. Because the Yellow River flows through the Loess Plateau,
tourist resources
The vibrant upstream reach-this reach is called the "rich mining area" of the Yellow River's hydraulic resources. Among them, from Longyang Gorge to Qingtongxia, rivers and canyons alternate with each other, with large riverbed gradient and rich hydraulic resources. The planned utilization gap exceeds 1.200m, and the installed capacity exceeds1.0 million kilowatts, accounting for nearly 50% of the whole river. The average annual power generation is nearly 60 billion kWh.
The tender and lingering Ningmeng reach-the Yellow River flows peacefully here, irrigating the farmland on both sides and benefiting the local people. Therefore, there is a saying that "Huang Hefu and Ningxia are the best in the world" and "the Yellow River risks only one side is rich". The land near Yinchuan, Ningxia is flat and has a vast area. For more than 2000 years, the Yellow River has been used for gravity irrigation. There are abundant products here, and the precious Chinese herbal medicines Lycium barbarum and Yinchuan rice are of good quality, which is known as "Jiangbei". Photo of Lycium barbarum The Hetao Plain in Inner Mongolia is very dry. In the west, the annual precipitation is less than 200mm. Here, "no water is a desert, and water is an oasis". The Yellow River water has created superior conditions for industrial and agricultural production here.
The middle reaches of the Yellow River-Shaanxi-Gansu-Ningxia Gorge, where the Yellow River splits the Wan Ren Mountain like a bamboo, forming the longest continuous canyon section on the Yellow River. There are two famous places in this paragraph:
Hukou Waterfall-The Yellow River rushed here with thunderous momentum and roared away. Hukou Waterfall is not only a symbol of the Yellow River, but also a symbol of the Chinese nation's indomitable spirit of pioneering and forging ahead. The majestic song "The wind is roaring, the horse is roaring, the Yellow River is roaring, and the Yellow River is roaring" sings the elegance of the Yellow River, and even sings the heroic spirit of the Chinese nation's invincible and hard struggle.
Longmen-The story of "Carp yue longmen" originated from this. It is said that carp can jump over the dragon gate and become a dragon. This legend expresses people's good wishes to reach their ideal state after hard work, and also inspires Chinese children to strive for self-improvement and struggle. According to legend, it is a canyon dug by Dayu, so it is also called Yumenkou.
Related culture
654.38+0.5 million years ago, the Xihoudu ape-man appeared in Ruicheng County near the Yellow River in Shanxi Province. Later, Lantian ape-man 6.5438+0 million years ago and Dali ape-man 300,000 years ago fished and thrived on the banks of the Yellow River, and continued to work silently for the birth of the Yellow River civilization.
70,000 years ago, the early Homo sapiens in Ding Cun, Xiangfen, Shanxi Province, and the late Homo sapiens in Dagouwan, Uxin Banner, Inner Mongolia, 30,000 years ago played the prelude to the ancient Yellow River civilization.
The microlithic cultural sites from 10000-7000 years ago, the Neolithic cultural sites from 7000 to 3700 years ago, the bronze cultural sites from 3700 to 2700 years ago and the iron cultural sites appearing in 770 BC are almost all over the Yellow River basin. Since the Middle Stone Age, the Yellow River Basin has become the development center of ancient culture in China. Suirenshi, Fu and Shennongshi created and invented artificial fire technology, primitive animal husbandry and primitive agriculture, which opened the prelude to the development of the Yellow River civilization.
Qin Huang Hanwu, Tang Zong Song Zu, a generation of arrogant Genghis Khan, these emperors led the Chinese nation to push the ancient Yellow River civilization to the brilliant peak that attracted worldwide attention. Gunpowder, compass, papermaking, printing, Tang poetry and Song poetry, and Yuanqu are glittering treasures in the Yellow River civilization. Inventions and scientific achievements not only promoted the development of China, but also spread all over the world and promoted the progress of all mankind.
First of all, the fifth longest river in the world
The Yellow River, the fifth longest river in the world, is a 5464-kilometer-long river winding in the north of China. From the air, it looks like a huge word "Ji" and is also a unique totem of our nation.
Second, the characterization of the Yellow River
Not just a big river. Yellow River, Yellow Land, Emperor and Yellow Peel, all these yellow appearances sublimate this turbid stream flowing through the heart of China into a holy river. Han Shu Gou Ji regards the Yellow River as the head of thousands of waters: "China has the source of all rivers, not in the four capitals, but in the river."
Third, the theory of loess weathering.
In a long geological time, in the desert Gobi in the interior of Asia, the sand everywhere is decomposed and crushed in the harsh environment of rapid cooling and rapid heating until it forms powder. The northwest airflow prevailing in the inland has blown them to the east for many years, and the coarse sand has fallen on the Mongolian plateau, and the most delicate powder has fallen to today's six provinces of Gansu, Shaanxi, Shanxi, Qinghai, Ningxia and Henan. After millions of years of transportation and accumulation, a loess plateau has finally formed, starting from the Great Wall in the north, reaching Qinling Mountain in the south, Sun Moon Mountain in the west and Taihang Mountain in the east.
Fourth, the deep and vast loess layer.
This is an unparalleled loess, with an area of 4 1 1,000 square kilometers, and the thickness of loess coverage is generally above 1 1,000 meters. The loess in Longdong, Shaanxi, Shanxi and other places is as deep as 100 to 200 meters, and the thickness in Lanzhou is more than 300 meters.
The Garden of Eden five or six thousand years ago.
Botanists have found that although the rainfall in the Loess Plateau is not as abundant as that in the south, the leaching loss of nutrients is also less, which is very suitable for the growth of poplar, birch, oak, Pinus tabulaeformis, spruce, jujube and Vitex negundo. At that time, lush vegetation gave birth to a warm and rainy Garden of Eden. Today, Shanxi, Shaanxi, Gansu, Ningxia and other provinces have large areas of virgin forests. Henan Province, located in the Central Plains, is referred to as "Yu" for short. It can be seen that in the era of word-making in Cangjie, it was still a place where elephants haunted.
Six, the foundation of historical prosperity
Geologists have found that loess has excellent understanding and is suitable for digging caves to live in; Agronomists found that all kinds of minerals in loess are rich in nutrition and high in natural fertility. The ancestors gradually dug caves in this yellow land to live in and made a living by planting grain. More than 5,000 years ago, the Yellow Emperor and Yan Di tribes thrived, and the footprints of Chinese ancestors traveled all over the yellow land. In the days that followed, China's first Wang Chaoxia flourished here, the 800-year-old Founding Power Week started here, and the Qin Empire, which swept Liuhe and unified the whole country, also flourished here.
Seven, the enlightenment of ancient civilization
Charred animal fossils and antler fossils were found in Houdu human activity site in Ruicheng, Shanxi, more than 6.5438+0.6 million years ago, and many carbon deposits were found in Lantian human site in Shanxi, 6.5438+0.6 million years ago.
Since then, Lantian people, Dali people, Dingcun people and Hetao people have all thrived in the embrace of the Yellow River. Until 6000 years ago, matriarchal clan culture represented by Banpo civilization appeared on the yellow land.
Our ancestors hunted and gathered in such a green field and spent the golden childhood of Chinese civilization.
VIII. Historical account of achievements in transforming nature
It is indeed the first place to bathe in the light of civilization, and it must be the first place to be touched by the fire of civilization. According to ancient legends, Shennong once taught people to grow crops. What is intriguing is that Shennong is Emperor Yan, that is, Vulcan, and what he teaches is actually burning forests for farming.
Mencius recorded the "achievements" of the three emperors and five emperors who burned the forest: "When Yao ... the vegetation was lush, the animals multiplied, the grain was not harvested, and the animals were threatened ... Yao was the only one who was worried, and he handled it well. Make good use of fire. The fierce mountain burned it, and the animals fled. "
In the Book of Songs, we heard the ancestors chanting when they cut down trees: "Kan Kan cut sandalwood, the river is dry, the river is clear, and the blue waves are rippling." "When logging is tintin, birds sing."
Nine, the loess plateau vegetation suffered heavy losses for the first time.
When the first emperor unified the six countries, a large number of people entered Guanzhong, and the reclamation area increased greatly. At the same time, large-scale construction, the construction of the palace mausoleum, wantonly cut down the Guanzhong mountain forest. In the thirty-third year of the First Emperor (2 14 BC), Meng Tian defeated the Xiongnu and gained a large area of land in Hetao. Later, he settled in other places to defend the border and immigrated to the Ordos Plateau many times, with hundreds of thousands of people each time. The originally endless grassland has become a farming area.
Ten, the loess plateau forest suffered heavy losses for the second time.
During the Western Han Dynasty, the population of China suddenly increased to 60 million. Expanding immigration to the northwest has become the main means to solve the pressure of population expansion. During the period of Emperor Wu of the Han Dynasty alone, more than 700,000 people moved to the northwest frontier fortress. The Western Han Dynasty drove the Huns to the distant Mobei, and turned large areas of forests and pastoral areas into agricultural areas. The irrigation project of diverting water from the Yellow River developed in Hetao during the Western Han Dynasty was at the cost of great damage to the forests of Helan Mountain in Ningxia, Inner Mongolia and northern Shaanxi.
XI。 Expose the bottom of the river
A few days ago, a century-old wonder "uncovering the bottom of the river" appeared in Dajinzui and Xiaoshizui sections of Shanxi Hejin section of the Xiaobei main stream of the Yellow River (Shanxi and Shaanxi sections), and the sediment at the bottom of the river was rolled up like a carpet by the current.
The phenomenon of "uncovering the bottom of the river" is a unique law of sediment movement in the Yellow River, which mainly occurs in Longmen, the main stream of Xiaobei, and Weihe, the tributary of the Yellow River. Its performance is that when the flood peak with high sediment concentration passes by, the riverbed is seriously washed in a short time, and the massive and flaky sediment at the bottom of the river is rolled up like a carpet, and then swept away by the current. Such intense scouring can make this section of riverbed several meters to more than ten meters deep in a few hours to dozens of hours. Due to the special conditions of the phenomenon of "uncovering the bottom of the river", "uncovering the bottom of the river" is called the century-old wonder of the Yellow River.
It is reported that the Yellow River was last "uncovered" on July 6, 1977 at/kloc-0. This "river bottom revelation" began at 8: 00 on July 5 and lasted until 8: 40. During this period, in the spur dike section of Xiaoshizui Reconstruction Project 1 in Hejin reach, two large-scale lifting objects 1 with a height of about 1 m and a length of about 7-9 m were hoisted successively with the turbulent underwater sound.
At the beginning of July, the tributaries from Wubao to Longmen in the middle reaches of the Yellow River were flooded with heavy rain, and the flood carried a lot of sediment south. On the evening of July 4th, the flood peak discharge of Longmen Hydrological Station at the source of Hejin reached 4600 cubic meters per second, and the maximum sediment concentration was more than 700 kilograms per cubic meter, which created conditions for the phenomenon of "uncovering the bottom of the river" in some areas.
XII. Yellow River Poems
At Heron Hill, Don Wang Zhihuan.
The sun sets slowly near the western hills, and the Yellow River flows into the East China Sea. By going up one flight of stairs, look further.
Liangzhou porcelain Tang Wang paper ring
The Yellow River is getting farther and farther away, because it flows in the middle of the Yellow River, and Yumenguan is located on a lonely mountain. Why use the elegy of willow to complain about the delay of spring, old Yumenguan, a spring breeze is not blowing!
Two Yellow River Poems by Du Fu in Tang Dynasty
The Haixi Army on the north bank of the Yellow River, gongs and drums ring all over the world. There are countless iron horses, and the conference semifinals are crowded with high noses.
"An epic ode? The Yellow River "Tang Hu Ceng.
Wang Bo was buried, no longer rotating, and the Yellow River was still at a loss. Down the river to * * * cowherd language, had to spirit if heaven.
Fan Zhongyan, a fisherman on the river
People who come to the river often only love perches. Look at those poor fishermen, floating up and down in the big waves and rocking in the boats.
Su Shi, Hui Chong Riverside Xiaojing
Two or three peach blossoms outside the bamboo forest and ducks in the water first noticed the warm spring. The beach is covered with wormwood, asparagus is beginning to sprout, and puffer fish are preparing to swim upstream from the sea back to the river.
"Yellow River" Wang Song Anshi
Send Kunlun five-color flow, a yellow turbidity filled Zhongzhou. Blowing sand and beating waves for thousands of miles, turn to the side of the house and ask nowhere.
On the Jianghu-Wang Anshi
The autumn shade in Jiangbei is half open, but the clouds are rainy but low. There is no road in the green hills, and there is another village. Suddenly, I saw Qian Fan looming.
Poetry of the Yellow River —— Ode to the Yellow River
Ode to the Yellow River is one of the movements of the Yellow River Chorus, which consists of three parts: overture, main body and ending.