我国农业面源污染及其控制措施（Agricultural non-point source pollution and its control measures in China）

1、我国农业面源污染及其控制措施（Agricultural non-point source pollution and its control measures in China）Agricultural non-point source pollution and its control measures in ChinaAbstract: agricultural non-point source pollution refers to the pollution of water environment caused by excessive use of pesticides, chem

2、ical fertilizers and livestock manure in agricultural production. At present, the use of chemical fertilizers and pesticides in China is still excessive, farm production of organic fertilizer of copper, zinc content is too high, resulting in a decline in surface water and underground water eutrophic

3、ation, soil quality, serious problems of public health risks. This paper analyzes the present situation of agricultural non-point source pollution, the source and harm process of agricultural non-point source pollution, and probes into the control methods of agricultural non-point source pollution.C

4、hina's environmental pollution is generally divided into point source pollution and non-point source pollution. Point source pollution refers to the pollution emitted by stationary sources, and non-point source pollution is also called non-point source pollution. It means the pollution without f

5、ixed emission sources. Agricultural non-point source pollution mainly refers to the excessive use of pesticides, fertilizers and livestock manure in agricultural production, resulting in pollution of water environment. At present, over reliance on and excessive use of chemical fertilizers and pestic

6、ides in agricultural production in China, the problem of agricultural non-point source pollution is still very outstanding, "12th Five-Year" the country launched the water pollution control projects, it is the important link of non-point source pollution research and comprehensive governan

7、ce. Through the analysis of the current situation of agricultural non-point source pollution and the source of pollutants from process analysis, this paper discusses the control methods of agricultural non-point source pollution, and expects to provide some reference for accelerating the research an

8、d management of agricultural non-point source pollution in china.1 status of agricultural non point source pollution in ChinaChina is a large agricultural country, from the beginning of 70s a lot of nitrogen fertilizer, combined with other facilities and technology, so that China's grain yield s

9、ubstantial, with total area of less than 10% of world arable land to feed the world accounted for nearly 20% of the population. At present, China has become one of the main consumption countries of nitrogen fertilizer in the world. The annual amount of nitrogen fertilizer reaches 25 million T, and t

10、he amount of per unit area is 3 times of the world average. According to the United Nations Food and Agriculture Organization (FAO) statistics, in 2002, China's nitrogen fertilizer use has ranked first in the world, accounting for 30%1 of the total nitrogen fertilizer application. Practical rese

11、arch shows that the utilization rate of nitrogen fertilizer in China is only 30% - 35%, the annual loss of nitrogen fertilizer is 15 million T, and the direct economic loss is 30 billion yuan 2. The long-term excessive application of nitrogen fertilizer brings great pressure to the environment. At p

12、resent, the amount of nitrogen fertilizer in China is about 400kg/ Hm2, which is much higher than that of developed countries to prevent the chemical fertilizer from polluting the water. The safety limit of 225kg/hm2 is 3. Chaohu, Taihu and other areas have appeared large eutrophication caused by ex

13、cessive nitrogen, threatening the production and living of the people in the lake area 4. With the groundwater as the main source of the northern region, almost all of the city's groundwater nitrate levels were increased significantly, according to reports, the Jilin corn belt of two typical reg

14、ional groundwater nitrate nitrogen content ranged from 0.02 to 160.68mg/L, average 14.83mg/L, of which 25.6% of the surveyed nitrate content in water affected by human activities the 26.9% wells in nitrate nitrogen content than the allowable limit of international security (NO - 3 - N = 10mg/L), the

15、 content of nitrate nitrogen in drinking water for more than 16.9% of the wells cap China (NO - 3 - N = 20mg/L 5). In addition, the accumulation of excessive nitrate in the soil and other vegetables into the body and residues, harmful to human health. Therefore, the low utilization rate of nitrogen

16、fertilizer will bring about direct economic losses, harm the environment and threaten human health.The problems of diseases and insect pests in agricultural production are prominent in China, and a large number of pesticides are used. During the period of 11th Five-Year, the consumption of pesticide

17、s in China increased by 9%, and the amount of crops used by the police was 56 times as much as that of the grain crops. In 2010, China's pesticide consumption was 1 million 322 thousand T, its utilization rate was only 30% 40%, most of the pesticides lost into the water, soil and agricultural pr

18、oducts, a serious threat to people's health and life safety 6. In addition, China's livestock and poultry breeding industry developed rapidly, livestock and poultry manure output reached 4 times more than industrial solid waste emissions.2 the formation process of agricultural non-point sour

19、ce pollution in China2.1 excessive use of fertilizers, pesticides and other agricultural products is the main source of water pollutionWith the decrease of arable land in China, agricultural production forms high input and high output. Agricultural production in some areas appear on a large number o

20、f chemical fertilizers and pesticides to replace the farmland management situation, Xu Aixia revealed that 7, years of continuous nitrogen, nitrogen fertilizer on crop yield in nitrogen fertilizer decreased gradually, the growth rate is far greater than the yield rate; low interest rate of nitrogen

21、fertilizer and crop has become one of the main reasons the yield is not high 8. Excessive fertilizer application not only increases the cost of agricultural production, but also reduces the efficiency of fertilizer, resulting in a large amount of nutrients remaining in the soil, and with the loss of

22、 soil and water into rivers and lakes. According to statistics, about 11000000 t of chemical fertilizer is lost every year in China, and 20% 30% of cultivated land has excessive nitrogen nutrition in China. 9. In addition, excessive application of N and P fertilizer, and insufficient potassium ferti

23、lizer, led to soil structure damage, resulting in greater pollution. Pesticide 80% 90% lost soil, water and air, 10% 20% residues in crops 10.2.2 unreasonable treatment of rural waste is one of the important sources of agricultural non-point source pollutionChina's agricultural production wastes

24、 including crops straw, farmers in some areas by way of straw burning treatment, not only caused by air pollution, also caused the water flows into the river with harmful substances burning ashes. China's rural households scattered garbage and industrial consumer goods such as waste, constructio

25、n waste, waste electronic products, the majority of farmers to be dumped on both sides of the river, in the storm period easily with water into rivers and lakes, rivers and lakes sedimentary formation of solid waste, reduce the water storage capacity of river lake and reservoir formation in the hydr

26、ation. The potential danger, some deposits of harmful substances dissolved in the water, such as heavy metals and electronic products dissolved, but also the formation of water pollution. Therefore, our country in the "12th Five-Year" water treatment project, specifically for rural waste t

27、reatment of environmental protection research deployment, but also the source of agricultural non-point source pollution control work.2.3 livestock and poultry breeding wastewater and waste discharge is the new source of agricultural non-point source pollutionIn recent years, intensive and mechanize

28、d breeding industry has developed rapidly in China. Because of the increasing proportion of fertilizer application in agricultural production, the treatment and utilization rate of livestock and poultry waste water and waste is less than 40%11. Without treatment of livestock manure into the soil, wi

29、ll contain bacteria, Escherichia coli and other pathogenic bacteria to destroy microorganisms, soil structure, some bacteria absorbed by plants and enter the food chain, the risk in the health of the masses. For the treatment of livestock and poultry manure into the river, will be harmful to aquatic

30、 organisms, such as fish and shrimp farming.2.4 farmland water and soil erosion is the main process of agricultural non-point source pollutionThere are plains and mountains in agricultural land in china. Irrigation plain area is too large, such as the Ningxia plain irrigation water reached 1500 200m

31、3/hm2, caused by irrigation water leaking into the ground and return to the river; land in our country mountainous area, slope farmland is very prominent in the problem of soil erosion during the rainfall period, especially in the rainstorm period of crop growth season, making a large number of soil

32、 the nitrogen and pesticide loss in rivers and lakes, not only affects the crop yield, also caused the loss of nitrogen and organic pesticides and nutrients into the water, the formation of water eutrophication, water quality and reduce the harm to aquatic organisms. Especially in some loose soil ar

33、eas, such as the serious loess plateau area where the soil erosion is serious in the middle reaches of the Yellow River, and the mountainous areas in the middle and upper reaches of the Yangtze river.3 agricultural non-point source pollution control measures3.1 non engineering control measures of ag

34、ricultural non-point source pollution(1) change the consciousness of environmental protection with various channels. Through the government guidance, media publicity, and economic means, change the mass ideology, improve the overall awareness of environmental protection of the whole nation. In Augus

35、t 2012, the environmental protection law of China was amended, which put forward new requirements for the establishment of a harmonious society of social, economic development and environmental protection. In view of the rapid development of China's social economy, the implementation of environm

36、ental awareness must be promoted by economic means.There are some very good countries in the world for environmental protection, such as Austria, Finland and so on. They take fertilizer tax, Denmark chemical fertilizer and insecticide, which is a good inspiration for our country 12. Our country can

37、expect in environmental governance, especially the economic law with the macro-economic regulation and control non-point source pollution control in the market, to farmers and farm owners using economic means to levy environmental taxes, guide them to take the initiative to protect the environment a

38、nd control pollution.(2) strengthen the legislation and execution of environmental protection. Due to the strengthening of enterprise management, the treatment of point pollution in our country is relatively successful, such as the online monitoring of enterprises in sewage treatment, so that China&

39、#39;s industrial wastewater discharge significantly reduced. For the non-point source pollution, due to the large scope, pollution sources and other characteristics, comprehensive governance requires a certain degree of technical and financial support. Therefore, according to the new environmental p

40、rotection law, the relevant laws and regulations on agricultural non-point source pollution should be strengthened, and the total emission control plan should be formulated and implemented to the grass-roots units and key pollutant discharge units. At the same time, we should strengthen the related

41、technology research of non-point source pollution control, such as the control of nitrogen fertilizer and the development of long-term nitrogen fertilizer, the development of environment-friendly pesticides.(3) increase the capital input of non-point source pollution control. To deepen the new envir

42、onmental protection act, the implementation efforts, comprehensive investment by state and local government funding, public participation and environmental capital fund raising and other means to establish the fund of agricultural non-point source pollution control, such as the city of Beijing in th

43、e new rural construction in Shunyi District, through propaganda, farmers will pay 49.18 yuan / person face the source administration fee, the region reached 26 million 808 thousand and 610 yuan 13. The government uses the funds to open up financial resources for non-point source pollution control, e

44、nvironmental protection infrastructure construction and non-point source pollution control projects.3.2 agricultural non-point source pollution control of engineering measures(1) strengthening soil and water conservation project to reduce non-point source pollutants into water body. Soil and water c

45、onservation is a national policy of our country, which not only promotes the protection of land and soil, but also promotes the loss of non-point source pollution such as chemical fertilizers and pesticides into water bodies and lakes. Especially in the Loess Plateau region, the upper and middle rea

46、ches of the Yangtze River, the wind erosion and water erosion area in the northeast. In the soil and water conservation work, in addition to maintaining water to rainfall and soil conservation index control, should increase and strengthen the control of soil and water in chemical fertilizer, pestici

47、des and harmful pollutants, improve the quality control of soil and water conservation.(2) control agricultural chemical fertilizer and pesticide and other agricultural products input, improve its utilization efficiency. Should strengthen the development of efficient and environmentally friendly pes

48、ticide fertilizer type and application, the implementation of the regional agricultural fertilizer and pesticide total control, encourage and promote the application of controlled release fertilizer, fertilizer synergist and soil improvement agent, highly effective and environmentally friendly pesti

49、cides and fermentation processing of livestock and poultry manure, control non-point source pollution from the source, at the same time reduce agriculture the production cost, improve the utilization efficiency of wind fertilizers and pesticides.(3) strengthening the remediation and treatment of pol

50、luted water and soil. In the treatment of water pollution, the potential of strengthening the ecological purification of wetlands is huge. For example, Northeast China, the Yellow River and the Yangtze River are rich in wetland resources into Haikou, and some wetlands in plain and mountainous areas.

51、 Adsorption, wetland plants and animals and microbes on non-point source pollutants absorbed and transformed, the purification effect of non-point source pollution, and low cost, long time, and bring great economic and social areas and ecological effects; in addition, focusing on some of the rivers

52、and lakes, to centralized management and total control, 12th Five-Year the national water special treatment has an effect on the protection, but more needs repair.(4) strengthen the rural environmental governance, promote the transformation and utilization of waste and livestock manure, and comprehe

53、nsively improve the rural non-point source pollution control. In the construction of new socialist countryside, we should strengthen the construction, disposal and utilization of waste and electronic products waste, and vigorously develop biogas production from livestock manure fermentation. The dev

54、elopment of biogas with livestock manure can solve the rural energy, and the waste residue produced by biogas production can be used as organic fertilizer. Biogas residue contains nitrogen, phosphorus and potassium nutrients needed by crops,It also contains crop stress resistance hormone and so on, which can reduce the amount of pesticide use in farmland to 70% 80%, promote the development of organic agriculture and pollution-free 14 of agricultural products.4 ConclusionStudy on pollution and control of agricultural non-point source is resear