1. non-point source pollution
Soil erosion and farmland drainage are important factors affecting the overall water quality of the Yangtze River. On the one hand, soil erosion brings pesticides, fertilizers, nutrients and some animal and plant humus into the water body, which increases the concentration of suspended solids, BOD, COD and total phosphorus in the water body. On the other hand, the sediment concentration in the Yangtze River has increased, and the total soil erosion in the Yangtze River basin is 2.4 billion t, including 65.438+0.8 billion t in the upper reaches and 600 million t in the middle and lower reaches below Yichang. Chongqing and Sichuan have become major sediment transporters, and Sichuan imports 680 million tons of sediment from the Yangtze River every year. The annual sediment discharge of Tuojiang River is between 3.42564 million t, and that of Jialing River is as low as 32.25 million t and as high as 357 million t, and even the sediment concentration of two tributaries of Jialing River is surprisingly high, with 2.93 million t-610000 t in Fujiang and 7.32 million t-150000 t in Qujiang River.
2. Point source pollution
In recent years, with the rapid development of industry and agriculture in the basin, the scale of cities has been expanding, and the surface water pollution in the basin has become increasingly serious. The sewage discharge in the whole basin has reached 654.38+0.5 billion tons, accounting for 45.2% of the total industrial wastewater in China. The amount of domestic sewage is 3.58 billion t, accounting for 35.7% of the total domestic sewage in China. Especially in Sichuan, Chongqing, Hubei, Hunan, Jiangxi, Jiangsu and Shanghai, the sewage discharge is 65.438+0.205 billion t, accounting for 84.6% of the total in the whole basin. However, the urban sewage treatment rate in the main stream of the Yangtze River is 48.3%, and the compliance rate is 56.9%. The sewage treatment level is lower than the average level in the river basin and the whole country. Sewage discharged from sewage outlets along the Yangtze River is the fundamental cause of coastal pollution in the main stream and major tributaries of the Yangtze River. In recent years, with the economic development of the Yangtze River basin, the sewage discharge in the whole basin has increased by 3% year by year, and most of the sewage is directly discharged into the river without treatment.
3. Mobile source pollution
There are more than 654.38+million transport ships in the main stream of the Yangtze River, and most of them are not equipped with oil-water separation devices and domestic sewage treatment devices. Millions of tons of oily sewage, nearly 1 100 million tons of domestic sewage and 750 million tons of domestic garbage are discharged into the Yangtze River every year, which constitutes a watershed pollution source that cannot be ignored in the Yangtze River. Moreover, in recent years, there have been frequent capsizing accidents of ships transporting chemicals, and a large number of chemicals such as sulfuric acid, cresol, kerosene and crude oil have been capsized into the river, which has made the destruction of water resources in the Yangtze River even worse.
4. Solid waste pollution
Solid waste refers to the solid residues of various substances used in industrial manufacturing, construction, cooking, entertainment, agricultural production and other activities, including: expired newspapers, glass bottles, metal cans, paper cups, plastic bottles, abandoned vehicles, rubber, slag, animal fur, floating dust, sludge, food residues and so on. A large amount of solid waste accumulated along the Yangtze River is another important reason for polluting the water quality of the Yangtze River. 1992, the annual output of solid waste in the three Gorges reservoir area alone reached 4.62 million tons, and the storage capacity reached 2 1.7 million tons. These untreated solid wastes are washed by floods and leached by rain, and all kinds of toxic substances easily enter the water body, seriously polluting the water quality of the Yangtze River.
5. Other pollution
Dust and wastewater discharged from industrial production flow into the water body through direct landing or rainwater leaching; Rainfall and surface runoff after rain bring atmospheric and soil pollutants into water bodies; Backwashing or infiltration of seawater pollutes groundwater sources or water bodies in coastal areas; Pollutants on the urban surface enter the water body. All these have polluted the water quality of the Yangtze River to some extent.
Second, the Yangtze River Basin Water Pollution Prevention and Control Countermeasures
The water resources of the Yangtze River are the material basis for the survival of more than 400 million people in the Yangtze River basin and the basic guarantee for economic and social development. In order to realize the strategic goal of water resources protection in the Yangtze River in the new period and realize the sustainable development of the basin, the following countermeasures are put forward for water resources protection in the Yangtze River basin:
1. Raise awareness of water resources protection
Although the Yangtze River basin is relatively rich in water resources, the total amount is still limited and the distribution in time and space is uneven. Water is also a very fragile natural resource, which is easily polluted and destroyed. People must renew their ideas and improve their understanding of the importance of protecting water resources in implementing the strategy of sustainable development and promoting all-round social progress. Strengthen publicity and education and supervision by public opinion in various ways, so that all sectors of society and the public can understand and abide by the water law, enhance people's awareness of water resources protection, especially improve the awareness of leading cadres at all levels on national environmental protection policies, enhance their sense of urgency and crisis, and make water resources protection a conscious act of the whole people. Establish a perfect public participation system, and Qi Xin will work together to speed up the pace of prevention and protection, leaving a beautiful water environment and living space for present and future generations.
2. Strengthen the supervision and management of the Yangtze River basin.
The compartmentalized management system artificially separates the systematic and perfect water system, and it is difficult to achieve "unified planning and rational layout" for "multi-dragon water control". The protection of water resources should follow the principle of combining water resources with water environment and paying equal attention to water quality, implement unified management, realize macro-control, formulate and plan the objectives, measures and requirements of water resources protection in the whole basin, straighten out the relationship, improve the organization, strengthen the protection and management of water resources in the basin, and accelerate the construction of decision support system for water resources protection.
① Improve the water environment monitoring network and strengthen the monitoring capacity building. On the basis of the existing water quality station network, improve the water environment monitoring station network as soon as possible, increase the investment in water quality monitoring, and improve the monitoring emergency capacity. According to the watershed water function zoning, optimize the layout of drinking water sources, and strictly control the total amount of sewage discharged by stations or points in key protected river sections and major sewage outlets. Adopt advanced science and technology, improve the sampling ability, analysis ability and information processing and transmission ability of monitoring station network, gradually establish an automatic monitoring station network for water quality, timely and accurately reflect the water quality status and water pollution prevention and control effect to relevant departments, and serve the management and protection of water resources and water pollution prevention and control.
② Further improve the management of water intake permit. It is necessary to strictly control water intake, limit the water consumption of enterprises with large water consumption and serious pollution, strictly manage the quality of backwater, and strictly supervise all enterprises and units that take water from the Yangtze River.
(3) Strengthen the supervision of the total amount of sewage entering the river. While rationally planning the sewage outlets into the river, it is necessary to strengthen the supervision and management of newly built and expanded sewage outlets into the river in accordance with the Water Law, the Water Pollution Prevention Law and other relevant laws and regulations. Those that exceed the requirements of total control shall be dealt with according to law.
④ Promote the construction of water resources protection and strengthen the comprehensive management of water pollution with source control as the main factor. For a long time, industrial pollution has been mainly treated at the end, with high cost and poor effect. To implement the strategy of sustainable development, we must change to the whole process pollution control based on source control, including selecting pollution-free raw materials and adopting advanced technology and equipment with light pollution to reduce pollution emissions. Industries and enterprises that cause serious pollution in the Yangtze River basin shall be ordered to carry out treatment within a time limit to meet emission standards; If it cannot be handled according to the regulations, adjust its industrial structure or implement "shut down and turn".
3. Improve the legal system
(1) The legislative concept of sustainable development runs through the Constitution.
The water resources in the Yangtze River basin play an irreplaceable role in the sustainable development of China. Although the current Constitution stipulates the principles of protecting the environment, preventing and controlling pollution and other public hazards, and protecting natural resources in the form of the fundamental law of the state, it does not explicitly take sustainable development as the guiding ideology for environmental and resource protection. China's "Environmental Protection Law" and other laws and regulations on environmental protection, pollution prevention and protection of natural resources also have this problem. However, China's Ten Countermeasures and White Paper on Environment and Development all regard the implementation of sustainable development strategy as a major strategy for modernization. This shows that China's environmental and resource laws and policies are seriously out of line. In addition, in the single natural resources laws and regulations formulated in the 1980s, China did not take ecological environment protection as an important legislative purpose in guiding ideology, and did not make specific provisions on ecological environment protection in natural resources development, which made it difficult for these natural resources laws to meet the needs of ecological environment protection, and should be revised in time to increase the content of sustainable development. Sustainable development is based on the protection of natural resources and the environment. Development and resource and environmental protection are interrelated and form an organic whole, which should be embodied in the fundamental laws of the country.
(2) Reform the sewage charge system
First, improve the charging basis, from centralized charging to total emission charging. The combination of concentration index and total amount index and the implementation of total amount control on the basis of emission concentration control are not only consistent with the main environmental protection tasks of implementing total amount control of major pollutants during the Ninth Five-Year Plan period in China, but also can fundamentally solve the problem of air and water diluting pollutants and effectively reduce pollution emissions.
The second is to use multi-factor superposition charges instead of single-factor charges. For multiple pollutants from the same pollution source, the polluter should take full responsibility for their pollution behavior, which conforms to the polluter pays principle.
Third, the charging standard should be adjusted according to economic development and price level changes, so that the charging level is slightly higher than the operating cost of equipment, which can stimulate enterprises to operate equipment to control pollution.
Fourth, we should change from excessive sewage charges to pollution charges. No matter what kind of pollution, we should levy sewage charges and excessive fines, make full and rational use of resources, and control the degree of environmental pollution within the environmental carrying capacity.
(3) Total emission control of key pollutants
In order to implement the total emission control system of key pollutants stipulated in Article 16 of the Law on the Prevention and Control of Water Pollution, this Regulation is re-enacted on the basis of absorbing local legislative experience and practical experience in total emission control and pollutant discharge permit.
(4) Establish emission trading system.
As an important economic means of environmental protection, emission trading system has become a widely used system in developed countries. Some scholars believe that under the market economy, more economic means must be used to promote the development of environmental protection. In legislation, some environmental resources should be regarded as commodities, and a trading system of emission rights should be established. Under the premise of total amount control and concentration control, environmental resources should be gradually distributed with compensation. Enterprises that obtain such resources can put them on the market for trading, just like obtaining a commodity. The trading mode is mainly in the form of paid transfer of pollutant discharge permit, and the total amount of pollutant discharge is controlled by the market mechanism. China's current environmental legislation does not clearly stipulate the right to pollution, and the corresponding system has not yet been established. In order to meet the needs of environmental protection in China, we must improve the legislation in this area as soon as possible.