Heyuan to Guide is a mountainous and grassland plateau; The ownership of the Qinghai-Tibet Plateau; Above 3000 meters above sea level; Mountain peaks above 4000 meters; Source valley at an altitude of 4200 meters. Guide's reach from Jinmeng River is the Loess Plateau, with the western slope of Lvliang in the east, Weihe Valley in the south, Ordos Plateau in the north and Lanzhou Valley in the west. The elevation of the Loess Plateau is generally at 1, 000 ~ 1, 300 meters, with uneven terrain and deep slopes. The gully slope is 65,438+0.5 ~ 20 degrees, and the gully area accounts for 40 ~ 50%. Gully density is 3 ~ 5 kilometers per square kilometer, and the cutting depth is more than 1 meter. 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, a lot of sediment is deposited, and the riverbed is 4 ~ 5 meters above the ground. Due to the repeated diversions of the Yellow River, fan-shaped ancient riverbeds and ancient natural dikes are alluvial on the ground, becoming an inclined plain with alternating gentle hills and depressions, and the depressions are relatively open and flat.
The Yellow River runs from Guide to Minhe at an altitude of 3,000 to 1.600 meters, and enters Gansu from Minhe Xiachuankou. The climate in this section is mild and humid, and it has the reputation of "small south of the Yangtze River on the plateau", and the water flow is crystal clear, and it is also known as "the Yellow River is precious in Deqing". Ningxia Plain in Ningxia and Hetao Plain in Inner Mongolia are called the Yangtze River because they are located in the upper reaches of the Yellow River, rich in water resources, convenient for irrigation, developed in agriculture and rich in aquatic plants. The Yellow River reaches Hekou Town, Tuoketuo County, Inner Mongolia Autonomous Region, with a total length of 3,472 kilometers. The middle reaches are Hekou Town to South Mengjin of Hukou Waterfall, with a 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. Flowing through 9 provinces; It has gathered more than 40 major tributaries and more than 65,438+0,000 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 longest 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. Due to soil erosion, 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+600 million tons, and the average sediment concentration is 35 kg/m3. According to world record association, China, the Yellow River has the largest sediment concentration. Main tributaries The main tributaries of the Yellow River are Baihe, Heihe, Huangshui, Zuli, Qingshui, Dahei, Kuye, Wuding, Fenhe, Weihe, Luohe, Qinhe and Dawenhe. Weihe River is the largest tributary of the Yellow River. The main lakes are Zhaling Lake, Eling Lake, Wuliangsuhai Lake and Dongping Lake.
In recent years, the organisms in the Yellow River waters have been destroyed, and now there are less than 100 species of fish. The technicians of Lanzhou Fishery Technology Extension Center believe that the ecological environment in the upper reaches of the Yellow River has deteriorated and soil erosion has led to a large sediment concentration in the Yellow River. Due to drought and lack of rain, the water volume of the Yellow River is decreasing. Wastewater pollution in industrial towns; Artificial fishing and other factors are the reasons for the decrease of water quantity in the Yellow River.
In order to restore the ecology of the Yellow River and protect biological resources, the Fisheries Department of Gansu Provincial Agriculture and Animal Husbandry Department began to implement the "Proliferation and Release" plan for the Gansu section of the Yellow River in 2000. According to the person in charge of the fishery department, the number of fish released has increased from more than 7 million last year to 8 million this year, with carp, catfish, grass carp and bighead carp as the main targets. 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 of1‰; 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 from Hekou Town, Tuoketuo County, Inner Mongolia to Jin Meng, 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 meters, 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 of the tributaries of this reach flow through the loess hilly and gully region, which is the main source of coarse sediment in the Yellow River. Among the 65.438+0.6 billion tons of sediment transport in the whole river for many years, 900 million tons come from this interval. 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. The two banks of this river 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 Jin Meng 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 long-term sedimentation in the lower reaches has formed a world-famous "hanging river on the ground", 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, and the average net land is 25-365.438+0 square kilometers/year. [Edit this paragraph] Humanities Water Conservancy Project * Sanmenxia Water Conservancy Project: Shanxi Pinglu and Henan Sanmenxia junction, Sanmenxia Water Conservancy Project was put into use on 1960.
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 contributes to 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! What's more, soil erosion has obviously reduced soil fertility, resulting in a large-scale reduction of crop production. 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. [Edit this paragraph] Development and change The Yellow River has been cut off since 1972. There are many reasons for disconnection, which can be summarized as follows:
1. Global Warming-With the intensification of global warming in recent years, on the one hand, the evaporation of river channels has increased greatly, and on the other hand, the glaciers in the upper reaches melt and absorb a lot of heat in spring and summer, which leads to the local temperature in the inland being lower than normal, and the temperature difference between the inland and the ocean is reduced, 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 melts glaciers and increases the upstream water flow, it cannot offset the effects of increased evaporation and weakened monsoon. The water volume in the middle and lower reaches is decreasing year by year.
2. Vegetation destruction-The vegetation in the Loess Plateau is seriously destroyed, and the land lacking vegetation conservation is gradually desertified, with high evaporation. 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 economically underdeveloped border areas, young and old, 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.
① The upper reaches belong to arid and semi-arid areas, with low precipitation rate, and the middle reaches are the main recharge areas, but the soil erosion is serious, the seasonal changes are great, the downstream area is small, and the recharge amount is small;
(2) The population growth in the basin is fast, and the population growth rate far exceeds the grain growth rate;
In recent decades, with the development of society, the industrial and urban water consumption along the Yellow River has been increasing, and the irrigation area of the Yellow River has been expanding.
(4) The reservoir regulation capacity is low, and the water resources management is not unified;
⑤ Low water fee can't arouse people's awareness of water saving, and industrial and agricultural water is wasted;
⑥ Environmental pollution greatly reduces the utilization rate of the Yellow River water.
⑦ Excessive sewage discharge from factories along the river.
waterfall
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Due to sediment deposition, in most sections of the Yellow River with a total length of 5,464 kilometers, the riverbed is higher than the cities and farmland in the basin, and it is constrained by dikes, so it is called "suspended river". So where did the Yellow River become a "hanging river"?
Dengkou County, southwest of Bayannaoer City, Inner Mongolia, where the Yellow River is 4 to 6 meters higher than the county seat 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". The Yellow River is the second largest river in China, and it has been a sediment-laden river since ancient times. In the 4th century BC, the lower reaches of the Yellow River were called "turbid rivers" because of its turbid water. /kloc-at the beginning of the 0 th century, it was pointed out that "the river is heavy and turbid, and there are six buckets of mud for one stone". Sediment increased after Tang and Song Dynasties. Some of these sediments are accumulated on the downstream river bed, which is accumulated over time and highly silted, all of which are constrained by dikes and form a suspended river for a long time. During the flood season in autumn and summer, the defense is weak, and the river is diverted from the top to the river. According to historical records, in the three or four thousand years before 1946, the lower Yellow River burst 1593 times, the river changed its course 26 times and burst 1000 times. The flood starts from Haihe River in the north and reaches Huaihe River in the south, covering an area of 250,000 square kilometers, which has a great impact on the geographical environment of the Huang-Huai-Hai Plain in China.
As far as the characteristics of the changes in the lower reaches of the Yellow River are concerned, it can be roughly divided into the following stages.
(1) Dike before the Warring States Period
The upper limit began in the Neolithic age. At that time, the lower reaches of the Yellow River flowed through Hebei Plain and entered the sea on the west bank of Bohai Bay. Because there are no dikes on both banks, the river course is extremely unstable. According to documents, the Yellow River has made many trips, including three sections recorded in Gong Yu, Shan Hai Jing Bei Shan Jing and Han Shu Geography. The first two roads are in the west of Hebei plain, along the foothills of Taihang Mountain to the north. The lower reaches of the mountain pass generally flow northward to the southern edge of the alluvial fan of Yongding River, pass through Xiongxian County and Baxian County eastward, and enter the sea near Tianjin today. The lower reaches of the Gong Yu branch off from the Shanjing River in today's Shenxian County, passing through the middle of today's Hebei Plain and entering the sea east of Qingxian County. The great river in Han Zhi leaves the eastern foot of Taihang Mountain and flows through northeast Henan, northwest Shandong, southeast Hebei and northeast Huanghua County. Before the mid-Warring States period, these three rivers either dominated each other or existed at the same time, but it was common for them to flow through the big river in Han Zhi. In ancient times, "River" was the proper name of the Yellow River. According to the records in Hanshu and Shuijing Note, there are more than 10 waterways called "rivers" in Hebei Plain, which may all be the old roads of the Yellow River after some interruption and migration.
(2) the 4th century BC to early AD (from the middle of the Warring States Period to the end of the Western Han Dynasty)
In the middle of the Warring States period, after a large-scale embankment was built in the lower reaches, the fixed river course was the big river recorded in Hanshu 2 Geography, which ended the long-term situation of multi-stream diversion and frequent diversion, and we temporarily regarded it as the first major diversion of the Yellow River.
In the mid-Warring States period, the lower reaches of the Yellow River were sparsely populated. When the dike was first built, the width of the dikes on both banks was 50 Li Han (1 Li Han, equivalent to 414m today). Large streams (the mainstream of water) have to swim in dikes, and rivers have strong flood storage capacity and are not easy to burst. Since then, the number of teeth has increased day by day, and a large beach blocked on both sides of the inland waterway of the levee has been reclaimed to build the people's dike for self-defense. Those who are far away are hundreds of steps away from the water. As a result, the riverbed is forced, the river body twists and turns, siltation is rapid, and dangers are repeated. At the end of the Western Han Dynasty, the river course in Xunxian County of Henan Province today, "The river is higher than the flat", has obviously become a "suspended river". This is the result of increased soil erosion in the middle reaches of the Yellow River since Qin and Han Dynasties. In 1 1 year, Wang Mang broke the Yellow River eastward, and the flood between the river and Huaihe River lasted for 60 years.
③1~10th century (from Eastern Han Dynasty to the end of Tang Dynasty)
In 1 1 year (the third year of Wang Mang's founding), the Yellow River burst above Yuancheng (now Daming East, Hebei Province), and the river flooded to several counties east of Qinghe County. At that time, because the river decided to flow eastward, Wang Mang did not advocate blocking the mouth, because his ancestral grave in Yuancheng was not threatened. It is recognized that the flood lasted for nearly 60 years, which led to the second major diversion in the history of the Yellow River.
After nearly a thousand years, the lower reaches of the Yellow River were relatively stable, with occasional overflow and no large-scale diversion. The reason is:
First, during the Eastern Han Dynasty, a large number of nomadic people began to settle in the middle reaches of the Yellow River, returning farmland to graze, and secondary grasslands and shrubs replaced cultivated land, and soil erosion was relatively weakened.
Second, in 70 AD, under the leadership of Wang Jing, the flooded river in the late Western Han Dynasty was comprehensively controlled, and then a new river course was built, which roughly flowed through the Jilu border region, from Changshoujin (now in the area of West Wangbin, Puyang), from the great river in the Western Han Dynasty, along the Guluo River, through the south of Fan County today, diverted between yanggu county and Guluo River today, passed through the Yellow River and Ma Jiahe today, and then entered the sea in Lijin County, Shandong Province.
Thirdly, at that time, there were many tributaries in the lower reaches of the Yellow River, either entering the sea alone or flowing into other rivers, and there were some lakes and swamps along the way, which all played the role of flood diversion, sediment discharge and flow regulation.
④ 10 century ~ 1 127 (from the end of Tang Dynasty to the end of Northern Song Dynasty)
After nearly a thousand years of accumulation, the lower reaches of the Yellow River gradually silted up from the end of the Tang Dynasty. In 893 (the second year of Tang Jingfu), the estuary section was diverted for nearly a hundred miles. By the fifth generation, the frequency of crevasse increased obviously, with an average of less than three years.
By the beginning of 1 1 century, in today's Shandong Shanghe, Huimin, Binzhou and other cities and counties, the river surface has been "high-rise buildings almost exceeded the height". Since then, the location of the breach has moved up to Ganzhou (now Puyang, Henan) and Huazhou (now East Old Town, hua county). The general trend is that the river swings northward gradually. At the end of the Five Dynasties and the beginning of the Northern Song Dynasty, the Chihe River and the Henglong River were all located in the north of the big river in the Tang Dynasty.
1048, Shang (now Puyang dongchang lake Ji) burst its mouth, and its northward flow passed between Fuyang River and South Canal, while its downstream (now South Canal) and Boundary River (now Haihe River) entered the sea in Tianjin, which was called "Yellow River North School" in history. This is the third major diversion in the history of the Yellow River. (The Yellow River flows northward for three times: Shanghukun, Xiaowukun and Neihuangkou)
Yellow River-Poetry
Have you ever noticed how the water of the Yellow River flows out of heaven and into the ocean, never to return? -Li Bai's "Into the Wine"
The Yellow River falls into the East China Sea, and Wan Li writes it in his mind. -Li Bai's "Give Pei Fourteen"
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 should a strong brother complain about willow? Spring breeze doesn't go through Yumen Pass! -Wang Zhihuan's "Liangzhou Ci"
The vast desert is lonely, and the Yellow River sets the yen. -Wang Wei's March on the Fortress
The sun sets slowly near the western hills, and the Yellow River flows into the East China Sea. But as long as you climb a flight of stairs, you can broaden your horizons by 300 miles! -Wang Zhihuan is at the Heron Hotel.
I want to cross the Yellow River, but ice will block the ferry and Taihang Mountain will be covered with snow. -Li Bai is hard to go.
The Yellow River winds from a distant place, carrying thousands of miles of yellow sand. -Liu Yuxi's "Langtaosha"
Send Kunlun Wuse River, and a yellow turbid river runs through Zhongchuan. -Wang Anshi's Yellow River
"Hundred Gardens Wangjing guru, when the Yellow River gushes. In the poor autumn, there are no pedestrians in the wilderness, and Ma Shoudong knows who it is. "
Crossing the Yellow River is a hot topic, and leaving home for a few days is new. -Wang Changling
"Haixi Army on the north bank of the Yellow River, drums and bells ring the world." .
"The south bank of the Yellow River is my country. If you want to support your family, there is no millet." -Du Fu's two Yellow River poems
"Look at three doors, three doors open, and the Yellow River flows east, which is gone forever."
"Order Li Bai to change his poems and come from the water of the Yellow River!" . -He Jingzhi's Sanmenxia-Dressing Table
"There was a Yellow River flow in ancient times, but there is cultivated land today. The roads are soft, and the sea turns to dust. " -"Crossing the Yellow River Embankment" by Sadula, a poet of the Yuan Dynasty
"The Yellow River can hold soil, and the north wind hates rain and snow."
"The Yellow River comes to Kunlun in the west, and Wan Li touches Longmen".
"How magnificent the Xiyue is, and the Yellow River is like a silk sky".
"Let's explore the tiger's den in the desert and whip the horse in the Yellow River." -Li Bai
"unique, the yellow river is in the sky." -Wang Wei
"The earth is full of flowers and Yun Lan, and the Yellow River is yellow." -Li Shangyin
The Yellow River is white, it is autumn in Huang Yun, and pedestrians are worried about the river. -Bai Juyi
Every year, after the defenders defend Huang Jinhe, hand knives waving whips keep ringing day and night. In the late spring when it snows heavily, the Great Wall, a journey across the Yellow River and around Montenegro. -Liu's "Sorrow"
Yellow River-Proverbs
Don't cry until you see the coffin, and don't stop until you reach the Yellow River.
Huang Heqing, a saint appeared.
The Yellow River is evil, but rich.
You can't wash it if you jump into the Yellow River.
The Yellow River is disgusting and kind, while the Yangtze River is kind and evil.
When the Yellow River returns, she doesn't look at Sichuan, and Dai sister returns without looking at mountains.
Two breakthroughs in three years and one shift in a hundred years.
The Yellow River burst, and the county magistrate couldn't stop it.
The Yellow River has nine bends and eighteen bends, with a bowl of river water and half a bowl of sand.
There is still a day when the Yellow River will be clarified. How can people have no luck?