One of the main pollution problems
One is that urban water pollution is still very prominent. With the expansion of urban scale, the rapid growth of domestic sewage discharge, in 1998 for the first time more than industrial wastewater emissions. 2001, the national industrial wastewater emissions of 20.07 billion tons, urban and rural sewage discharge of 22.77 billion tons, of which the COD emissions of domestic sewage increased by 8% over the previous year, while industrial wastewater COD emissions during the same period was reduced by 13.8%. At present, the national urban sewage treatment rate of only 34.3%. Urban rivers have become sewage ditches. Large quantities of sewage discharged directly into the urban water environment deterioration, the seven major river basins in urban river sections have formed a clear pollution zone, as well as some of the city's drinking water sources are also contaminated.
The second is that urban air pollution, characterized by particulate matter in northern cities and acid rain in southern cities, is still relatively serious. The national urban gas penetration rate of only 60.2%, a considerable number of cities still use coal as the main civilian fuel, a large number of coal-burning caused soot-type pollution, sulfur dioxide concentration of the annual average value of the national secondary standards of the city accounted for 21%. Many cities are affected by acid rain, and many cities have high levels of particulate matter in the air due to the large amount of bare ground, unstandardized management of construction sites, and sloppy collection and transportation of soil and garbage. Of the 338 cities monitored nationwide, 63.5 percent failed to meet the second-tier national air quality standards.
Thirdly, domestic garbage is not properly disposed of, seriously affecting the environmental quality of surface water and groundwater. The annual volume of urban garbage is about 118 million tons, only 60% of which are treated and disposed of to different degrees, and 79 million tons of garbage are simply landfilled or piled up in the suburbs of the cities and along the rivers every year, which destroys the natural landscape of the cities (especially the urban-rural areas). In addition, all kinds of wastes generated by the tertiary industry and residents' life in each city are collected in a mixed way, and there are no special centralized treatment facilities for special wastes such as medical wastes, and the disposal or stacking of common household wastes becomes a hidden danger of spreading diseases and polluting the environment.
The fourth is the big city motor vehicle exhaust pollution is becoming more and more prominent. China has become the world's fourth largest producer of automobiles and the third largest consumer of automobiles, in 2004, the number of cars reached 27.42 million. In recent years, although the elimination of leaded gasoline, limit the content of other hazardous substances in gasoline, new cars with electric injection and three-way catalytic, the introduction of new emission standards and other measures, single-vehicle pollutant emissions have been reduced. However, due to the rapid increase in the number of motor vehicles, the total amount of pollutant emissions is still increasing. Cities such as Beijing, Shanghai, Guangzhou, Wuhan, Zhengzhou, Shenyang and other cities are heavily polluted by nitrogen oxides, and carbon monoxide on both sides of the traffic arteries seriously exceeds the standard, and the type of atmospheric pollution in some cities has been changed from soot-type to composite-type. In addition, the road growth and vehicle growth mismatch, modern traffic management means is insufficient, motor vehicles often idle condition, is also an important cause of motor vehicle pollution increased.
Fifth, noise pollution has become an important environmental problem affecting the quality of life of urban residents. Traffic, social life, building construction is the main source of noise pollution, at present, the transportation of urban noise pollution accounted for 70-80%. In 214 cities where traffic noise monitoring is carried out, 31.3% of the cities are in moderate or heavy pollution level. In 176 cities where regional environmental noise monitoring is carried out, 55.6% of the cities are in moderate or heavy pollution level. When some cities build elevated bridges to improve traffic conditions, they often fail to solve the problem of noise reduction and isolation on both sides of the elevated roads, and the lives of residents on both sides of the traffic arteries are greatly affected.
In addition, urban greening, urban population and other factors is also a major problem facing the urban environment, urban ecological imbalance problems continue to be serious, "urban heat island", "urban desert" and other problems. At the same time, the degradation of urban natural ecosystems has exacerbated the contradiction between the supply of resources and environment and the economic and social development of cities. These urban environmental problems are not solved, will seriously constrain the healthy development of urban economy and society.
Two, the main recommendations to solve the urban pollution
Comprehensive improvement of the urban environment to maximize the overall function of the city from the start, the use of comprehensive measures to improve, protect and shape the urban environment, in order to achieve the purpose of protecting and improving environmental quality. Take administrative, legal, economic and scientific and technological measures, the rational use of natural resources, to prevent environmental pollution and damage, in order to maintain ecological balance, expand the reproduction of useful natural resources, to ensure the development of human society, in order to coordinate the relationship between economic construction, urban and rural construction and environmental construction, to take the road of sustainable development.
1, rational planning, improve the city function. Follow the ecological law, from the city's environmental capacity and resources to ensure the ability to formulate and implement urban master plan, rationally determine the size of the city and the direction of development, adjust the city's industrial structure and spatial layout, and gradually solve the problem of mixed urban functional areas, accelerate the construction of urban environmental infrastructure, improve the urban ecological environment.
2, the treatment of urban water pollution. All cities should formulate plans to improve water quality, focusing on the protection of urban drinking water sources. cities with a population of more than 200,000 people to establish a water quality reporting system, environmental protection key cities to implement the environmental quality of drinking water source water reporting system. Adopting measures such as intercepting sewage, treating sewage, clearing silt, guaranteeing water for urban rivers and lakes, accelerating water exchange, maintaining urban wetlands, etc., to make urban surface water reach the standard according to its function. Comprehensive use of price, administrative, scientific and technological and engineering measures to promote urban water conservation, sewage treatment and its resource utilization, to create water-saving cities. Strictly control the amount of groundwater extraction, strictly prohibit over-exploitation of groundwater.
3, the treatment of urban air pollution. Increase the proportion of clean energy in cities, improve the energy structure, large and medium-sized cities to build high-polluting fuel no-burn zone, in densely populated urban areas to gradually cancel the direct combustion of raw coal. Promote the active utilization of natural gas in cities along the west-east gas pipeline. Accelerate the construction of urban heating and gas supply capacity. Prohibit the construction of new coal-fired power plants and other enterprises that seriously pollute the air environment in the suburbs of cities. Vigorously develop public **** transportation, encourage the development and use of clean-fuel vehicles, and gradually raise and strictly enforce pollutant emission standards for motor vehicles. Large and medium-sized cities as well as urban agglomerations should comprehensively control the interaction of urban air pollutants. In accordance with ecological requirements for greening, landscaping and hardening, the environmental management of building construction and road transportation should be strengthened, and urban dust should be effectively controlled. The establishment of urban air quality daily reports and air quality forecasting system in key cities.
4, the treatment of urban garbage pollution. Accelerate the urban garbage treatment and comprehensive utilization, safe disposal of hazardous waste and other urban environmental protection infrastructure. Establishment of garbage collection, storage and transportation and treatment system, in priority to garbage, solid waste reduction and resource-based, based on the implementation of harmless garbage and hazardous waste centralized safe disposal. The establishment of waste batteries recycling and treatment system. medical waste in cities with a population of more than 200,000 must all be safely disposed of, and encourage the centralized disposal of medical waste.
5, control urban noise pollution. Strengthen the supervision and management of construction, industrial production and social life noise. Restrictions on motor vehicles, trains in urban areas, the cause of sensitive buildings exceeding the acoustic environment of the heavy traffic load section, take noise reduction measures to control traffic noise pollution.
6, do a good job of environmental protection in key cities. Comprehensive consideration of the size of the city, nature, regional distribution and environmental conditions and other factors, the national environmental protection of key cities expanded to 113, and increase the comprehensive environmental remediation efforts. Continue to carry out activities to create national model cities for environmental protection, and enhance the comprehensive capacity of model cities for sustainable development. Improve the mechanism of public, community and media participation in urban environmental management, and establish an emergency response system for urban environmental pollution.