The seven major water systems in order of pollution from heavy to light: Liaohe, Haihe, Huaihe, Yellow River, Songhua River, Pearl River, Yangtze River. Among them: Liao River, Huai River, Yellow River and Hai River basins have more than 70 percent of their sections polluted.
The Yangtze River
Taking a boat trip down the Yangtze River, and then circling around the cities of Chongqing, Yichang and Wuhan, it is shocking as far as the eye can see. Countless sewage outfalls like a sinful dragon, all day long clamor non-stop to the Yangtze River spewing venom. Countless piles of garbage are piled up along the river, and when they are piled up, they will naturally slide into the Yangtze River, and when the river rises, they will naturally carry the garbage into the river.
The Yellow River
One of the major benefits of the Yellow River's high sediment content is its excellent purification ability. The Yellow River, which is heavily polluted in Qinghai, purifies itself as it flows in, especially after it reaches the reservoir area of the Liujiaxia Hydropower Station, where it settles and flows out of the Liujiaxia with Class I water quality. However, after only hundreds of kilometers, it becomes class III water when it enters Lanzhou city. When it flows out of Lanzhou City, it becomes Category IV water, and after flowing through Baiyin City, it drops to Category V water. A large amount of industrial and domestic wastewater is constantly being discharged into the Yellow River.
Water pollution is serious for a variety of reasons:
China's water pollution is mainly affected by three factors, one is industrial pollution, in the future, even if all the industries are rationally laid out, sewage discharge of all standards, treated sewage is also super-five. Second, urban sewage, our country to fully meet the treatment and discharge will take a long time. Third, the surface source pollution, that is, farmland application of fertilizers, pesticides and soil erosion caused by nitrogen, phosphorus and other pollution, this problem is more troublesome, China is the world's highest intensity of the use of chemical fertilizers in the country. Compound pollution caused by a variety of factors will make the deterioration of water pollution in China will become more and more serious Ai Wei Tiancheng.
In developed countries, the reuse rate of industrial water reaches more than 80%. And sewage must be treated and discharged to meet the standards. And China's water reuse rate is much lower than this. Most enterprises can not do sewage completely treated and discharged to meet the standards.
In developed countries, there is an average of every 10,000 people have a sewage treatment plant to deal with people's daily sewage. In China, until the mid-1990s, China's domestic sewage treatment plants less than five. Wuhan, Chongqing and most other major cities have zero domestic sewage treatment rate. It was all discharged directly.
Seven watersheds:
1, the Yangtze River is China's largest river, also known as the Yangtze River, the length of the river is second only to the Nile River and the Amazon River, the amount of water into the sea is second only to the Amazon River and the Congo River, all ranked third in the world.
Overview of the basin of the Yangtze River originates in the Tanggula mountain range, the main peak of the southwest side of the Geladandong Snow Mountain (see color map of the source of the Yangtze River - Tanggula mountain range Geladandong Snow Mountain glacier on the southwest slope), the main stream through the Qing, Tibet, Sichuan, Yunnan, E, Xiang, Gan, Anhui, Jiangsu, Shanghai, tributaries involved in Guizhou, Guizhou, Gansu, Shaanxi, Henan, Guangdong, Zhejiang, Fujian, * * * * There are 18 provinces, autonomous regions and municipalities directly under the central government. The length of the main stream is 6300km, and the basin area is 1.807 millionkm. The larger tributaries are: Yalong River, Minjiang River, Jialing River, Wujiang River, Xiangjiang River, Yuanjiang River, Hanjiang River, Ganjiang River, etc., with a basin area of more than 80,000km. The main stream from the source of the river to Yichang for the upper reaches of the river length of 4510km, in addition to the Sichuan Basin, most of the flow through the high mountains and canyons, steep slopes and fast-flowing, drop 5360m, accounting for 98.9% of the total drop of the river. Among them, the source of the river to Dangqu is about 360km long, called the TuoTuo River; Dangqu to Yushu Batang River mouth is about 820km long, called the TongTian River; Batang River mouth to Yibin is about 2300km long, called the Jinsha River; Yibin to Yichang is about 1,000km long, called the Chuanjiang River. The lower part of Sichuan River is 209km long from Fengjie to Nanjin Pass, which is the famous Three Gorges. The lower part of Yichang enters the middle and lower plains. The middle reaches from Yichang to the mouth of Poyang Lake is about 940km, and the lower reaches below the mouth of the lake is about 850km. In the middle reaches, from Zhicheng in Hubei Province to Chenglingji at the outlet of Dongting Lake is about 340km long, known as Jingjiang River, with meandering channels and low-lying terrain along both sides, which is the most serious section of the Yangtze River in terms of flood control situation. The middle and lower reaches of the plains are densely populated with lakes, and the main lakes through the river are Dongting Lake, Poyang Lake, Chaohu Lake, Taihu Lake and other four major freshwater lakes.
2. The Yellow River, the second largest river in China, is world-famous for its high sand content and frequent floods in history.
Overview of the basin The Yellow River basin starts from Ba Yan Ka La Mountain in the west, and faces the Bohai Sea in the east, and extends to the Qinling Mountains in the south and the Yinshan Mountains in the north, with a basin area of 752,000 kilometers. The Yellow River originates from the northern foot of Ba Yan Ka La Mountain on the Qinghai-Tibet Plateau, flows through 9 provinces and autonomous regions such as Qinghai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shanxi, Shaanxi, Henan, Shandong, and injects into the Bohai Sea in Kenli County of Shandong, with the total length of the main stream of about 5,400 kilometers, from the source of the river to the upstream of Toktor, Inner Mongolia, in which most of the areas are covered with better plants above Lanzhou, and there are more canyons in the main stream from Mado to Qingtongxia, which are rich in water energy resources; Below Qingtongxia is the Hetao Plain, where irrigation is well developed and shipping is possible. The middle reaches from Toktor to Taohuayu in Henan Province are also rich in hydro energy resources; both sides of the river are Loess Plateau, with little vegetation and serious soil and water erosion, which is the main source of sediment for the Yellow River floods. Peach Blossom Valley to the mouth of the river for the lower reaches, most of the two sides of the construction of the embankment, sediment siltation so that the riverbed is generally higher than the ground on both sides of the 3 ~ 5m, more up to 10m, so it is called a hanging river; along the coast of the irrigation areas, the main stream can also be navigable. Near the mouth of the river, the Yellow River into the sea waterway constantly siltation, extension, rerouting, land-making effect is strong. There are ten tributaries with a watershed area of more than 10,000km which are directly connected to the main stream in each river section, and the area and water volume of Weihe River are the largest.
3, the Pearl River by the West River, the North River, the East River and the Pearl River Delta rivers, four water systems, distributed in China's Yunnan, Guizhou, Guangxi, Guangdong, Hunan, Jiangxi six provinces (autonomous regions) and the northeast of Vietnam's socialist **** and the country. The mainstream of the Pearl River is the Xijiang River, which originates from the Mashong Mountain in Yunnan Province and injects into the South China Sea at the Mudao Gate in Zhuhai City, Guangdong Province, with a total length of 2,214 km. The area of the entire basin is 453,700 km, of which 442,100 km is within the territory of China.
Overview of the basin The Pearl River Basin is located in the subtropical zone, with a mild climate and abundant water resources, with an average annual runoff of 336 billion meters, second only to the Yangtze River, ranking second in China. The average annual precipitation is 1,477mm, and the intensity of precipitation during flood season is so high and the speed of convergence is so fast that it is easy to form basin floods with high peaks and large amount of floods lasting for a long period of time, which is a serious threat to the lower reaches of the Pearl River and the delta which is economically developed. During the dry season, there will be no or little rain for three consecutive months, resulting in spring or fall drought. From the Yunnan-Guizhou Plateau to the coast of South China Sea, the Pearl River has a total drop of 2,136m in its main stream, with a theoretical reserve of 33.48 million kW of hydropower in the whole basin, mainly concentrated in the lower reaches of the Nanpanjiang River of the Xijiang River, and the sections of the Hongshui River and the Qianjiang River, with an installed capacity of 25.12 million kW of hydropower, which is one of the bases for the development and construction of hydropower in China.
4. The Haihe River Basin is located in North China and is one of the earlier developed basins in China.
Overview of the basin The Haihe River Basin customarily includes the Haihe River and Luanhe River systems. The Hai River system consists of the Zhangwei River, Ziya River, Daqing River, Yongding River, Chaobai River, North Canal, Ji Canal, etc. It also includes the Tujia River, Mahehe River and other plains drainage channels; the Luan River system consists of the Luan River and the Jidong Rivers. 1949 years ago, in addition to the Luan River system and the Jijie Canal, the Tujia River, the Mahehe River into the overseas, the rest of the rivers are converged to Tianjin and flow into the Bohai Sea. The river below Tianjin is called the Haihe River, with a main stream length of 73 km. The Haihe River Basin covers the cities of Beijing and Tianjin, most of Hebei Province, four provinces of Shanxi, Shandong, Henan and Liaoning, and part of the Inner Mongolia Autonomous Region. The total area of the basin is 318,000 kilometers (including 264,000 kilometers in the Hai River system and 54,000 kilometers in the Luan River system). The mountains and plains in the basin account for 60% and 40% respectively. The Yanshan and Taihang Mountains are distributed in an arc from northeast
to southwest. To the west and north of the mountains is the Loess Plateau; to the east and south of the mountains is a vast plain. The transition zone between the mountains and the plains is short and almost directly intersected. The general trend of the plain's topography is to tilt from the southwest, west, and north toward the Bohai Bay near Tianjin. As a result of the historical Yellow River's many diversionary invasions and the impact of the alluvial deposits of the tributaries in this basin, the plains area constitutes a complex terrain of slow hillocks and depressions interspersed with the distribution of deposits.
5. The Huaihe River is located between the Yangtze River and the Yellow River, with a basin area of 270,000km, of which the Huaihe River system covers 190,000km and the Yishu and Surabaya system covers 80,000km.
Overview of the Basin The main stream of the Huaihe River originates from the Tongbai Mountains of Henan Province, and flows into the Hongze Lake from west to east. It is divided into two branches: one flows into the Yangtze River through Gaoyou Lake and Shaobo Lake in the southeast of Yangzhou City, Jiangsu Province, which is called the waterway into the river, with a maximum flood discharge capacity of 12,000m/s; the other flows into the Yellow Sea through the North Jiangsu Irrigation Canal, with a design flood discharge capacity of 800m/s. In addition, it can also be drained through the Waste Yellow River with a discharge capacity of 300m/s, and diverted to the Xinyi River Camera through the Huaishu Xinhe River in times of great floods, with a discharge capacity of 3000m/s. The whole main stream of the Huai River is divided into two branches. The total length of the main stream is about 1,000km, and the main tributaries on the south bank are Shigong River and Luxi River, which originate from Dabie Mountain. On the north bank, the main tributaries are Hongru, Shaying, Eddy, Hwoe, Xinbian and Suixi. The northeastern part of the Huaihe River Basin is the Yishu-Si system, which was originally a tributary flowing into the Huaihe River from the Yimeng Mountains, and was diverted by the Yellow River from the end of the 12th century to the middle of the 19th century, taking over the channels of the Si River below Xuzhou and the Huaihe River below Huaiyin. During this period, due to the siltation and elevation of the Yellow River bed, the drainage of the Huai, Yi, Shu and Surabaya was blocked, resulting in the formation of the Hongze Lake, the Luo Ma Lake and the South Four Lakes (Nanyang, Dushan, Zhaoyang and Weishan lakes), which caused the Huai River to flow into the river in the south, and the Yishu and Surabaya Rivers to find another way to flow into the sea in the east.
The river has been reorganized since 1949, and is now a tributary of the Huai River. After the improvement since 1949, some of the water from the upper reaches of the Yishu River is diverted to the Xinshu River, and the rest is diverted to the sea through the Xinyi River; the Surabaya River flows into the Nansihu Lake, and then through the canal into the Luoma Lake, and receives the water from the Yishu River, which is discharged into the Xinyi River by the Roach Gate.
6, Songhua River is a major river in northeast China, flows through Harbin Jiamusi, in the same river near the injection of the Heilongjiang River, the total length of the main stream 939km.
Basin Overview Basin area of 546,000km, belonging to the three provinces of Inner Mongolia, Jilin and Heilongjiang, autonomous regions, of which the mountainous areas accounted for 61%, hilly areas accounted for 15%, the plains accounted for 24%. Basin east and west distribution of the three rivers plain and Songnen Plain, fertile land, grasslands in succession. The whole basin of about 200 million mu of arable land, and there are 30 million mu of wasteland can be reclaimed; the size of the Hingganling mountainous areas are densely forested, for China's famous forestry base; the Sanjiang Plain is rich in coal resources, in 1985 the output of raw coal
60 million tons; Songnen Plain for China's main oil base, built Daqing Oilfield, in 1985 the output of crude oil production accounted for China's crude oil production of half of the total output. The climate of the basin is long and cold in winter and hot and rainy in summer. The average annual temperature is -3~5 C, with a maximum of 40 C and a minimum of -50 C. The annual precipitation is generally 500mm, with 800mm in the southeastern mountainous areas and only 400mm in the southwestern plains, with large interannual variations and obvious patterns of alternating abundance and depletion. The river runoff is about 78 billion meters, the groundwater resources are about 37 billion meters, and after deducting the duplicated water, the total water resources are about 95 billion meters. Natural disasters in the basin are mainly floods and droughts, with floods in the east and droughts in the west. Floods are heaviest in the Sanjiang Plain in the east, occurring once every two years on average; droughts are heavier in the Songnen Plain in the west, with spring droughts predominating.
7, Liao River is located in the southwest of Northeast China, originating in Hebei Province, flowing through the Inner Mongolia Autonomous Region, Jilin Province, Liaoning Province, into the Bohai Sea.
Overview of the basin The whole basin consists of two water systems: one for the East and West Liao River, in the Fude store after the confluence of the Liao River, the Liao River mainstem, through the Shuangtaizi River by Panshan into the sea, the main stream length of 516km; the other for the Hun River, the Taizi River in the Sanchuo River confluence through the Daliao River by the Yingkou into the sea, the Daliao River length of 94km. the mainstem of the Liao River, the original water near the six room room diversion of the external Liao River convergence of the Daliao River. 1958 outside the mouth of the Liao River blocked after the upper mouth. After the blockage of the upper mouth of the Liao River in 1958, the main stream no longer communicates with the Hun River and the Taizi River, and has become an independent water system of its own. The total area of the basin is 219,000km. West Liao River Zhengjiatun above the Liao River for the upper reaches, an area of 136,000km, the climate in the region is arid, the main tributaries are Laoha River, teach to come to the river, the Xilamulun River and so on. Among them, Laoha River and Jialai River are located in the mountainous and loess hilly area of north Hebei and west Liaoning, with less than 30% of vegetation cover, and the soil and water erosion is very serious. The upper reaches of the river have about 26 million mu of cultivated land, which is mainly used for dry farming and animal husbandry. The lower and middle reaches of the basin cover an area of 83,000 km. The east side of the main stream of the Liao River is a stony mountainous area with good vegetation and abundant rainfall, and there are major tributaries such as the Dongliao River, the Zhaosutai River, the Qing River, the Chai River, etc., together with the Hun River and the Taizi River, the area of the water system is ****526,000 km, which accounts for 24% of the whole basin, while the annual runoff is about 70% of the runoff of the whole basin which is 15 billion meters; the west side of the main stream is mostly loess dunes, and there are the XiuShui River, the Liou River, the WunYang River and so on, among which there is serious soil erosion in the Liou River. The Liu River has serious soil erosion and is the main sediment producing area in the middle and lower reaches of the river. The middle and lower reaches are economically developed, with important industrial cities such as Shenyang, Fushun and Anshan, large-scale coal mines such as Fushun and Liaoyuan, power plants such as Liaoning and Qinghe, and iron and steel enterprises such as Anshan and Benxi, as well as the Liaohe oil fields and major railroads such as Shenshan and Dazhou and highway networks, and the existing arable land of 43 million acres, with 6.2 million acres of paddy fields within it, which is the main agricultural area of Liaohe River Basin, and the gross value of industrial and agricultural output accounted for 95% of the total value of the entire basin in 1980, and the total value of industrial and agricultural output accounted for 95% of the total value of the entire basin. In 1980, the total output value of industry and agriculture accounted for more than 95% of the whole basin.