The concept of agricultural fertilization needs to be transformed

Recently, some experts pointed out that overuse of chemical fertilizers can seriously pollute the soil and water sources. In the long run, it is easy to fall into a vicious circle of “more fertilizers are being applied and more land is being grown and thinner”, which threatens the sustainable development of agriculture in China. This phenomenon deserves vigilance.

"Fertilization is as addictive as taking medicine."

In Yandian Township, Feixi County, Hefei City, Anhui Province, Ma Yongxin, a large grain farmer who has planted more than 1400 mu of land this year, is working on wheat in the fields. Several farmers are wearing straw hats and masks. Nitrogen-filled plastic buckets, shuttled in the wheat field, spread fertilizer while walking.

“Now the amount of fertilizer used to plant 1 mu of land is 10 times that of 20 years ago.” This year, 57-year-old Ma Yongxin calculated a fertilizer account for the reporter: At least one season of wheat must be applied to basic fertilizer, jointing fertilizer, fertilizer, panicle fertilizer, etc. Fertilizer, and some farmers will also add boron and Other fertilizers to supplement the soil trace elements, an average of 1 mu of land to fertilize 80 kg of food per quarter.

"If you want high yields, chemical fertilizers must be invested in large quantities and have quick results. When nitrogen fertilizers are sprinkled on, the growth of wheat leaves is good. It looks like a bright green crop. Potassium phosphate fertilizers can make straw thick," Ma Yongxin said.

In the village of Zhongcao, Qiliying Town, Xinxiang County, Henan Province, the reporter met the farmer Ma Youyong who was pouring in the ground. For the large amount of chemical fertilizers he is now farming, he also has a deep understanding: “Compared to previous years, now The average compound fertilizer per mu is 10 kg more, and urea is also 5 kg to 10 kg more."

Reporters interviewed in major agricultural provinces such as Anhui, Henan, and Hebei found that many farmers have misunderstandings about the use of chemical fertilizers, and believe that to increase food production, it depends on fertilization. Mao Weidong, deputy director of the Soil Fertilizer Station at the Agricultural Bureau of Handan City, Hebei Province, introduced that many farmers believe that large-scale fertilizers can increase grain production. Such as wheat top-notch children, usually 1 acre to 20 kg can be fertilizer, but many farmers' fertilizer dosage is 30 kg to 40 kg, top-dressing more than 1 times.

Ma Zhiming, a farmer from Jiamu Village, Tangxian County, Shijiazhuang City, Hebei Province, told reporters that although the agriculture department's soil testing formula guides farmers how much fertilizer is used, we always feel that the agricultural sector will use less chemical fertilizer, and fertilizer nutrients will be lost. This is not enough fertility. Use more points. "Like a drug addiction, the doctor lets him eat a slice. He eats two pieces. He feels that the drug is powerful and effective. This is the case with habitual fertilization." Hao Hao, a farmer, used this analogy.

Utilization of low-polluting soil, the vicious cycle is worrying Reporters learned that, behind the sharp increase in farmers' fertilizer use, the overall utilization rate of fertilizer in China is relatively low, and a large number of crops have not been effectively absorbed by crops. Fertilizer is not wasted. With years of accumulation, it will also pollute soil and water quality, and reduce the quality of agricultural products.

Zhao Lianzi, deputy general manager of Henan Xinlianxin Chemical Fertilizer Co., Ltd., said: “The internationally recognized upper limit for chemical fertilizer application safety is 15 kilograms per mu. At present, the average application rate of fertilizer unit area in China is about 58 kilograms per mu, and the overall utilization rate is about 30. %, 70% are wasted."

According to Guo Xisheng, director of the Institute of Soil and Fertilizer Research at the Anhui Academy of Agricultural Sciences, overuse of chemical fertilizers is likely to cause three major consequences. First, volatilization into the atmosphere will exacerbate the greenhouse effect and air pollution; second, it will dissolve into rivers and lakes after rain and cause water bodies. Eutrophication and infiltration into groundwater destroy the quality of groundwater. Third, it leads to imbalance of nutrient structure within the soil, poor air permeability, and low conservation capacity, resulting in soil compaction, salinization, and acidification. Excessive fertilization, especially excessive application of nitrogen fertilizer, has become one of the important causes of agricultural non-point source pollution in China.

"Too much nitrogen will destroy the cells of the land and the soil will harden. The use of more potash will also pollute the groundwater." Ma Yongxin, Hao Kexiang and many other farmers are deeply impressed by the increasingly serious soil compaction. The most direct reflection It is now that the blade of a ploughing agricultural machine is often easily damaged and touched by the earth. It is harder than in previous years.

Grassroots agricultural cadres introduced that excessive application of chemical fertilizers also affected the crops themselves. For example, more nitrogen fertilizer will reduce the crop's own resistance, and it is easy to recruit pests and diseases. The application of fertilizers, pesticides, etc. is also closely related to the quality and safety of agricultural products. Excessive fertilization will lead to a decline in the quality of agricultural products.

Yu Baohai, deputy director of the Soil and Fertilizer Work Station of the Agriculture and Husbandry Bureau of Chengde City, Hebei Province, said: “For vegetables, if the amount of nitrogen fertilizer is too large, the residual components of the crop can easily be converted into subhalide salt, which will cause damage to human health.”

"Abuse and blindly applying chemical fertilizers have led to a decline in the quality of arable land year after year, and soil nutrients have failed to keep up. In turn, they have to apply more fertilizer. Such a vicious cycle will not be imagined in the future." Guo Xisheng expressed concern.

Finding the crux of the problem, the concept of remedy, fertilization concept needs to be changed. The reporter found that the current utilization rate of chemical fertilizers in China is not high, a serious waste, and our country's arable land use is not high, a direct relationship between decentralized management. Many farmers do not accept the scientific fertilization methods such as soil testing, formula fertilization, etc., and the fertilization method is not correct. The amount of organic fertilizers including farm manure and crop straws is greatly reduced, which has become the main “crux” of excessive fertilizer application.

In an interview, the reporter saw that many farmers often sprinkle fertilizer directly on the surface of the soil during fertilization, which not only reduces the absorption rate of the crop, but also easily causes the volatilization and loss of fertilizer and pollutes the environment. "If you can apply 20 centimeters underground, you can save at least 20% of chemical fertilizers," said Zhang Xibao, chief agronomist of Agriculture Commission of Anhui Feixi County.

Long-term application of chemical fertilizers tends to cause deterioration of soil quality and properties. Organic fertilizers traditionally used in rural areas in China can effectively increase soil fertility. However, some farmers reported to reporters that in recent years, with the increase of rural migrant workers in rural areas, there have been fewer and fewer pigs in rural areas, most of the pigsty is idle, and the source of farmyard fertilizers has become less and less, and they can only rely on chemical fertilizers to maintain their fertility.

Grassroots agricultural cadres and experts recommend that farmers should be guided as soon as possible to change the mode of fertilization and use of fertilizer structure, reduce the amount of fertilizer from the source. The agricultural sector should strengthen the propaganda, education, and technical guidance for the scientific fertilization of farmers, inculcate the correct concept of fertilization for farmers, and change the mode of extensive fertilization. At the same time, compared with ordinary farmers, large grain producers are more likely to learn scientific fertilization, fertilizer application methods and techniques to reduce planting costs.

Yu Baohai and others believed that under the premise of protecting the interests of farmers, efforts should be made to further increase the circulation of land and encourage more land flows to be handed out by large grain producers and family farmers, and to change the mode of overall scattered management of rural land in China, and improve The scale, intensive, and standardized production of the land will lead the large grain producers to fertilize and fertilize their fertilizers.

Increase the proportion of organic fertilizer application and improve soil quality to promote benign circulation. Guo Xisheng and other experts introduced that for the current increase in soil compaction and nutrient loss, inorganic fertilizer can only be a temporary solution can not be a permanent cure, and increase the application rate of green manure and commercial organic fertilizer can effectively enhance the soil organic matter. The nutrients of organic fertilizers are relatively comprehensive, but they can be co-administered with inorganic fertilizers because their strength and effectiveness are slightly smaller. At the same time, it is necessary to expedite the promotion of straw and other crops returning to the fields so that the land for fatigue rotation can be rehabilitated.