1. China's water environment problems and their influencing factors
The water environment in China is facing many pressures, such as water pollution, water shortage and flood disaster. Water pollution aggravates the shortage of water resources, and the destruction of water ecological environment promotes frequent floods. According to 1999 Bulletin on Environmental Status of China, the groundwater in seven major water systems, major lakes, coastal waters and some areas in China has been polluted to varying degrees. Rivers are dominated by organic pollution, and the main pollutants are ammonia nitrogen, biochemical oxygen demand, permanganate index and volatile phenol. The lake is characterized by eutrophication, and the main pollution indexes are total phosphorus, total nitrogen, chemical oxygen demand and permanganate index. The main pollution indexes in coastal waters are inorganic nitrogen, active phosphate and heavy metals. These factors constitute a wide range of water environment problems, which are serious and difficult to control. There are many reasons for the water environment problems in China, but they are mainly influenced by human subjective factors. For a long time, China's economic growth mode is extensive, and enterprises simply pursue economic benefits, ignoring environmental benefits and ecological benefits. In industrial development, water consumption is large and utilization rate is low. Not only is the amount of sewage discharged per unit output value large, but also the water consumption per 10,000 yuan output value varies greatly among provinces. 1998 The average water consumption per 10,000 yuan GDP in China is over 683m3. Including Beijing 16 1m3, Tianjin 20 1m3 and Shanghai 300m3. And Heilongjiang, Inner Mongolia, Jiangxi, Guangxi, Guizhou, Qinghai, Gansu and other provinces and regions are mostly above 1000m3. Ningxia and Xinjiang are about 4000m3. Beijing's 1m3 irrigation water can produce 2kg of grain, while Ningxia can only produce less than 1kg. At the same time, under the traditional planned economy system, the extensive economic growth mode makes enterprises lack the motivation to save energy and reduce consumption. The technological transformation of enterprises often aims at expanding reproduction, with backward production technology and slow upgrading. With the deepening of economic system reform, the transformation of economic growth mode and the rapid improvement of scientific and technological level, the rational development and utilization of water resources will gradually embark on the track of scientific management. However, this transformation needs a long historical process. Another important reason for the serious water environment problem is the deviation of national policy orientation. For a long time, national economic and social development has focused on economic growth rate, output of major products, income growth of urban residents and other indicators, but failed to bring resource consumption and environmental costs into the economic accounting system. So far, urban environmental infrastructure construction is still regarded as "unproductive welfare undertakings". Urban sewage treatment and garbage disposal are undertaken by the government, which is so overwhelmed that it is unable to build environmental infrastructure or even pollution treatment facilities, and it is difficult to operate normally because of unresolved sources of funds. Under the planned economy system, some economic development policies are contrary to environmental protection. Fifteen small enterprises that once blossomed everywhere in China were scattered in layout, uneconomical in scale and backward in production technology, which caused serious environmental pollution and ecological damage.
The disharmony between regional economic development and regional environmental capacity is also an important cause of water environmental pollution. In the past, when determining the direction of regional industrial development and the layout of regional productivity, the regional environmental capacity was often ignored. The serious water pollution in major river basins in China is directly related to the unreasonable industrial structure and layout of the basins. Since the early 1980s, the four provinces in Huaihe River Basin have made great efforts to develop small industries with high water consumption, such as chemical industry, paper making, leather making, thermal power and food, and the discharge of pollutants has exceeded the carrying capacity of Huaihe River, resulting in a sharp deterioration of water quality in Huaihe River Basin. Due to the lack of scientific certification and management, some water-deficient areas blindly develop high-water consumption industries, leading to the decline of groundwater level; In some resource-rich areas, develop a single resource-based industry, and do not develop matching processing industries. The industrial structure is similar and the structural pollution is serious.
The influence of natural factors has aggravated the deterioration of water environment problems to a certain extent, and increased the difficulty of water pollution prevention and control. In recent years, due to climate change, the global distribution of temperature, humidity and precipitation has changed, resulting in frequent disasters in some countries and regions. The climate in northern China is also obviously warming. The average winter temperature in North China in the 1990s is 2. 1℃ higher than that in the 1950s. As the temperature rises, surface runoff decreases, evaporation increases, and the probability of drought increases. During the period of 1997, the northern part of China was affected by the El Ni? o phenomenon, with unusually low precipitation and high temperature, and the seawater and river resources were only 40% of the multi-year average. The water resources of the Yellow River is 665438+ 0% of the average for many years. Due to the decrease of river runoff, the self-purification ability of water body decreases, which aggravates the deterioration of water environment. During the period of 1998, due to the El Ni? o phenomenon, there was too much precipitation in the middle and lower reaches of the Yangtze River, Nenjiang River and Songhua River basin, which led to catastrophic floods.
The regional distribution of water resources in China is uneven, with more in the south and less in the north, which is very different, and the distribution of water resources is extremely uncoordinated with the layout of population, economy and social development. The Yellow River, Huaihe River, Haihe River, Songliao River and inland river in the north account for about 47% of the total population, more than 65% of cultivated land and more than 45% of the national GDP, while water resources only account for 19% of the total water resources in the country, and the per capita possession is only13 of that in the south. These factors are also important aspects that lead to outstanding water environment problems.
2. The main problems existing in the prevention and control of water pollution in key river basins
Since the Ninth Five-Year Plan, the prevention and control of water pollution in key river basins in China has been guided by the Huaihe River, and Taihu Lake, Chaohu Lake, Dianchi Lake, Haihe River and Liaohe River have started one after another. By adopting a series of measures such as terminal treatment of industrial pollution sources, enterprises with backward production technology, backward equipment and serious pollution have been banned, closed and eliminated in the process of industrial structure adjustment and excess capacity reduction, and the treatment work has achieved certain results. Some waters are close to achieving the first-stage pollution prevention and control objectives. As the first large-scale prevention and control of river basin water pollution in the history of China, the Ninth Five-Year Plan has accumulated a lot of valuable experience, which has long-term strategic significance for opening up the road of environment and development in China. But on the whole, the progress of water pollution prevention and control in key river basins is still relatively slow, and the results are very fragile. Some problems exposed in practice fully show that the prevention and control of water pollution in river basins in China is still facing severe challenges at present and in the future.
2. 1 Water environment problems in the Yellow River and Yangtze River basins need to be solved urgently.
The management of "three rivers and three lakes" during the Ninth Five-Year Plan only opened the prelude to the prevention and control of water pollution in China. While treating "three rivers and three lakes" on a large scale, it must be noted that the pollution problems of the Yellow River and the Yangtze River have reached the point where they must be treated. The Yellow River, the cradle of the Chinese nation, has nurtured mankind and brought countless disasters to mankind. Nowadays, due to the influence of human activities, the environmental problems of the Yellow River are becoming more and more serious. 1999, on the key monitoring section of the Yellow River Basin 1 14, 70% of the water bodies are classified as Class V and 56.2% are inferior to Class V, respectively. The main tributaries of the Yellow River are seriously polluted, and the pollution of the Yellow River mainly comes from tributaries. At present, the Yellow River has little water, weak self-purification ability and water environment crisis. In the western development, the economic development of the Yellow River basin will enter a period of rapid growth. The water pollution of the Yellow River will inevitably make the shortage of water resources along the coast "worse".
With the rapid development of economy and society and the acceleration of urbanization in the coastal areas of the upper reaches of the Yangtze River, the discharge of pollutants in this area has increased rapidly, and the pollution problem has intensified, especially the water quality in the Three Gorges reservoir area and its upper reaches has been deteriorating. If effective measures are not taken, it is estimated that by 20 10, the wastewater discharge in key areas in the upper reaches of the Yangtze River will increase by 4.1%annually; The amount of domestic waste in towns along the Yangtze River will increase from about 2 million tons in 1995 to 4.67 million tons in 20 10. The self-purification capacity of water in the Three Gorges reservoir area will be greatly reduced. After the impoundment of the Three Gorges reservoir area in 2009, the reservoir area will be transformed from a river with fast flow rate and large discharge into an artificial lake with slow flow rate, long detention time and large backwater area. Water dilution and self-purification ability decline, and water pollution will inevitably increase. According to the forecast, after the completion of the Three Gorges Project, the concentration of main pollutants in the shoreline pollution area in the upper reaches of the lake area will increase by 2- 10 times compared with that before the dam is built, and it will become a heavily polluted area.
2.2 Urban domestic sewage is increasing year by year, and the construction of sewage treatment facilities is seriously lagging behind.
Urban infrastructure is the carrier of industrial construction, which restricts the scale and development speed of industrial construction. For a long time, China's urban construction has inappropriately reduced the carrier status of infrastructure construction to the general subsidiary status of industry, and the development of infrastructure is not coordinated with population, resources, environment and industrial construction, resulting in long-term overload operation of infrastructure. In particular, urban environmental protection infrastructure has only begun to be built in recent years. The sewage treatment capacity of most cities in China is far from meeting the actual needs.
With the rapid increase of population and the improvement of people's living standards, the amount of domestic sewage has greatly increased. In recent years, the proportion of urban domestic sewage and industrial wastewater discharge has been close to the same. However, the construction of urban sewage treatment plants is far from meeting the needs of economic and social development. Under normal circumstances, the construction period of urban sewage treatment plants is 3 years. Judging from the current construction progress, it will take quite a long time to meet the national requirements of building centralized sewage treatment devices in cities with a population of 500,000 during the Ninth Five-Year Plan period. Taking the Huaihe River as an example, according to the plan, by 2000, 52 urban sewage treatment plants will be built in the four provinces of Huaihe River Basin, with a total investment of 6.08 billion yuan, forming a sewage treatment capacity of 3.52 million L/d. By June of 1999, only three sewage treatment plants were built, and the sewage treatment capacity was only 440,000 L/d. The reasons for the slow construction of centralized sewage treatment facilities are not only the shortage of funds, but also the lack of funds. Because the "polluter pays" policy has not been really implemented, local finance is unable to pay the sewage treatment fee, which often makes the completed sewage treatment plant unable to operate normally, and the environmental protection investment cannot effectively play its environmental benefits.
2.3 A large number of non-point source pollution problems have not yet found a solution.
At present, the national industrial pollution has begun to be effectively controlled. By the end of 2000, all industrial pollution sources in China will meet the emission standards. Urban sewage treatment is gradually accelerating. However, the pollution of pesticides, fertilizers, livestock and poultry breeding brought by rural economic development is extensive and difficult to control. From 1950s to 1990s, the consumption of pesticides in China increased by nearly 100 times, making it the largest country in the world. The number of pesticide poisonings in China accounts for 50% of the global number of similar accidents every year. Moreover, due to the large loss of pesticides, serious water pollution has been caused. The use of chemical fertilizers in China is also increasing exponentially. 1995 is four times that of 1978. At present, the imbalance of nitrogen, phosphorus and potassium is more serious because of partial application of chemical nitrogen fertilizer. Moreover, the utilization rate of chemical fertilizer is only about 30%, and a large amount of chemical fertilizer is lost into rivers, oceans and lakes, which has become the main source of non-point source pollution of water bodies. At the same time, due to the use of a large number of chemical fertilizers, the agricultural utilization of livestock manure in rural areas has decreased, and the intensive degree of animal husbandry has increased, which has aggravated the disconnection between farming and planting. The rate of returning livestock manure to the field is only over 30%, and most of it is not used. During the period of 1998, the output of livestock manure in China was 3.4 times that of industrial solid waste in that year. Most of these animal wastes are directly discharged into rivers, lakes and oceans without treatment. At the same time, as an important part of rural economy, the development of township enterprises has always been a major problem that puzzles the rural environment. According to 199 1 and 1997, the emissions of sulfur dioxide, soot, chemical oxygen consumption and solid waste in township industries increased by 22.6%, 56.5%, 246.6% and 552% respectively. While the total discharge of major industrial pollutants in China has been controlled, the discharge of pollutants from township enterprises is increasing, which will pose a serious threat to the water environment.
2.4 Economic policies are not matched, and pollution control funds are seriously insufficient.
Under the planned economy system, China's pollution prevention and control funds mainly come from the national budget. With the establishment of the market economy system, it is no longer effective to govern the environment entirely by administrative means. However, because the environmental economic policy system under the market economy has not yet been established, it is difficult to form a diversified environmental investment system. As an important economic means to promote pollution prevention and control, the sewage charge system is still far from perfect. The main problem is that the sewage charges are too low to stimulate pollution prevention and control. As the main part of sewage charges, the charges for exceeding the standard are less than half of the operating expenses of pollution control facilities; The maximum sewage charges shall not exceed 0.5 yuan/liter; The sewage charges are incomplete, and the main targets are large and medium-sized enterprises and some institutions. Urban sewage treatment fee is only levied in a few cities, and the charging standard is low, which does not fully reflect the principle of "polluter pays"; The transfer payment mechanism of sewage charges has not yet been established, there is a lack of interest compensation policy between upstream and downstream in the basin, and the development, utilization and protection of water resources are not coordinated, resulting in waste of water resources.
During the Ninth Five-Year Plan period, China's investment in environmental protection has been greatly improved. In particular, the state has adopted a proactive fiscal policy and made environmental protection a key investment field to expand domestic demand. Some key water pollution prevention and control projects have been supported by national debt funds. However, due to the narrow channels of environmental protection funds and low investment, the shortage of pollution control funds is still very prominent. According to the plan, the water pollution prevention and control of "Three Rivers and Three Lakes" needs about 654.38+0.26 billion yuan, but the funds already implemented are far from the demand. From 65438 to 0998, the state issued additional financial bonds and bank loan funds for infrastructure construction, and allocated 65438 billion yuan of financial bonds to the Huaihe River Basin for the construction of urban sewage treatment plants. However, these funds only account for 16.5% of the total investment of Huaihe urban sewage treatment plants, and there are as many as 34 investment projects. Due to the lack of local matching funds, many projects have started, but due to insufficient funds and slow construction progress, many projects have not yet been invested.
3. Policy suggestions for water pollution prevention and control
China has achieved rapid economic development under the condition of relatively backward economy and technology. With a large population base and few per capita resources, it will be a long-term strategic task to prevent and control environmental pollution and ecological destruction. In particular, the solution to the problem of water environmental pollution cannot be achieved overnight, and it needs a hard treatment process. Therefore, we must conscientiously sum up the experience and lessons of water pollution prevention and control during the Ninth Five-Year Plan period, learn from all successful experiences in the world, and combine the specific conditions of our country, constantly strengthen policy innovation, system innovation and technological innovation, and gradually embark on a road of water pollution prevention and control with China characteristics.
3. 1 Control the new water environment decision.
When determining the speed of economic development, formulating national economic and social development plans, resource development plans and regional development plans, as well as formulating economic and technological policies and making major economic decisions, national and local governments at all levels should make a scientific assessment of the possible environmental impacts arising from the implementation of these decisions, and the assessment conclusions should serve as the basis for decision-making at all levels. When making decisions, environmental, economic and social factors should be comprehensively considered to minimize the impact of development on the environment. Establish a scientific evaluation index system, set up a special evaluation and appraisal institution, legalize this system, and gradually establish an operational mechanism for decision-making according to law.
The development of regional economy should give full consideration to the protection of water resources. Restrict the development of water-consuming industries in water-deficient areas, adjust the industrial structure in water-deficient areas, and strictly control construction projects with high water consumption, high energy consumption and heavy pollution. In the near future, we should focus on adjusting the industrial structure in the water-deficient areas in the north to prevent the shortage of water resources from further aggravating. In the economic development of areas with fragile ecological environment, we should consider leaving space for ecological water use to prevent rivers and lakes from shrinking, land desertification and ecological degradation in downstream areas caused by over-exploitation. In the water source area, guide and organize the construction of eco-economic system in the water source area to avoid water pollution caused by economic development in the water source area to downstream cities.
3.2 The development and utilization of resources should adhere to the principle of both open source and throttling.
Vigorously carry out water-saving activities and take effective measures to reduce water consumption. Organize the implementation of water-saving and efficient agricultural irrigation technology; Improve scientific agricultural water management measures and change the situation of large water consumption in agricultural production as soon as possible. Formulate water quota for unit products and assessment indicators for water reuse rate, and establish an assessment system for industrial water use; It is clearly stipulated that industrial wastewater such as cooling water and process water must be recycled; Vigorously develop the closed-circuit circulation of water to minimize wastewater discharge.
While saving water and solving the shortage of water resources in China, we should comprehensively strengthen the prevention and control of water pollution, especially in key river basins. The focus of river basin management is the treatment of urban industrial wastewater and domestic sewage. Centralized treatment should be combined with decentralized treatment, and sewage should be recycled. Construction of sewage treatment facilities according to local conditions, the treated sewage should be used for industrial cooling water, urban landscape and garden green space water.
3.3 Establish and improve the system of paid use of resources and the price system.
Relevant state departments should pay close attention to organizing and carrying out resource pricing research, formulate classified pricing policies for important resources related to the national economy and people's livelihood and national scarce resources in a planned way, and change the unreasonable situation that resource products are "valuable without market" and the prices are low as soon as possible, so that the prices of water resources can reflect the resource value, resource utilization and pollution prevention costs. At the same time, actively promote the process of capitalization management of water resources, strengthen the study of resource accounting system, and create conditions for gradually bringing water resources accounting into the national economic accounting system.
3.4 Improving environmental and economic policies
Pay close attention to formulating environmental economic policies conducive to environmental protection and further strengthen environmental economic means under the market economy system. Raise the standard of sewage charges as soon as possible to make it higher than the cost of pollution control; Formulate policies related to water pollution prevention and control, and establish a compensation mechanism for resource renewal; Fully realize the principle of "polluter pays", and generally increase the sewage treatment fee as the operating cost of urban sewage treatment plants in water charges; Environmental protection, as a "market failure" field, especially environmental science and technology research and development, environmental protection infrastructure construction and so on. The state should strengthen industrial policy support. At the same time, encourage and promote the enterprise construction and management of environmental protection infrastructure.
Actively establish an environmental tax system. Expand the scope of resource tax collection and levy resource tax on scarce resources such as groundwater; Levy adjustment tax on investment direction of fixed assets on newly-built pollution projects to control structural pollution; Analyze the advantages and disadvantages of the current sewage charges and fees changing into taxes, and explore the collection of pollution surcharges; Implement zero tax rate for enterprises engaged in urban sewage treatment; Preferential tax relief shall be given to the production of renewable resources and products produced by using renewable resources.
3.5 Vigorously promote cleaner production
Industrial departments should speed up the adjustment of industrial structure, rationally adjust industrial layout, and promote the development of high-tech industries with low resource consumption and high efficiency. Combined with technological transformation, clean production with clean raw materials, clean production process and clean products as the main contents will be carried out. Cleaner production should be a comprehensive transformation of industrial enterprises under the guidance of sustainable development strategy, and it should be popularized in all industrial enterprises in China. By strengthening environmental management audit and establishing a scientific management system, China's industry can be transferred to a new technology base, improving quality, reducing consumption and intensively increasing economic benefits. On this basis, we will gradually establish a resource-saving eco-industrial production system in China.
3.6 Strengthen the prevention and control of rural non-point source pollution
The rural areas should carry out the eco-agricultural production system with improving the agricultural ecological environment and accelerating the rural economic development as the main content. We will comprehensively promote the "big agriculture" mode of production with reasonable allocation of planting, breeding and processing industries, and pay attention to the all-round development of agriculture, forestry, animal husbandry, sideline production and fishery and the comprehensive management of agriculture, industry and commerce. Organically combine modern science and technology with the essence of traditional agriculture, gradually increase the use of organic fertilizers and reduce the use of chemical fertilizers and pesticides. Develop biological pesticide technology, popularize the use of bacteria to control insects, and replace pesticides with biotechnology to control pests. At present, there are more than 2,000 ecological agriculture pilot projects in China. On the basis of summing up experience, the implementation of ecological agriculture is widely carried out in rural areas of China as a revolution in rural economic development. Gradually transfer rural surplus labor from polluting township industries to ecological agriculture construction. County and township governments should make plans for the construction of ecological agriculture, and relevant state departments should strengthen technology popularization, train a group of technical backbones in towns and villages in a planned way, and guide farmers to develop ecological agriculture.
3.7 Accelerate the construction of urban sewage treatment plants and vigorously develop environmental protection industries.
Reform the current urban sewage treatment system and realize the socialization, marketization and enterprise of the construction and operation of sewage treatment plants. Competition mechanism should be introduced into the construction of sewage treatment plants. According to the principle of "whoever invests owns it, whoever manages it benefits", we will establish a model of diversified investment construction, enterprise operation management, social cost sharing and necessary policy support from the government. Actively explore the integrated management system of urban water supply and drainage construction and operation. Gradually liberate the government from the direct management of the construction and operation of sewage treatment facilities, and let sewage treatment really go to the market.
The development of environmental protection industry should become a new growth point of national economy. The state should formulate economic policies to support the development of environmental protection industries and give preferential treatment in investment, credit and taxation. Encourage some enterprises with surplus products to turn to environmentally friendly products and services; Establish an environmental protection industry group and form an industrial scale as soon as possible; Pay close attention to cultivating the environmental protection market and push the environmental protection services originally managed by the government to the market. At the same time, it is necessary to strengthen environmental scientific research and organize key water treatment technologies such as high-concentration organic wastewater treatment; Accelerate the localization of complete sets of equipment for pollution prevention and ecological engineering, change the backward status of China's environmental protection industry, and meet the needs of pollution prevention and control in China.
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