How to solve the problem of rational use of fertilizer
January 12 15:22:25, 2021
The so-called rational fertilization is based on plant nutrition, and determines the use of fertilizers and their rational use according to crop, soil, and fertilizer traits. It is the selection of fertilizers for plant nutrient characteristics, soil properties, and crop growth period, and adheres to organic fertilizers. Inorganic fertilizer combination; adhere to the soil, due to the rational fertilization of crops; adhere to the lack of prime ingredients, balanced fertilization; determine a reasonable rotation fertilization system, a reasonable allocation of nutrients; use of reasonable fertilization techniques to increase fertilizer utilization. According to the soil properties, the soil types in China are very different. The red soil, brick red soil, yellow soil, yellow brown soil and brown soil in the southern area are acidic or slightly acidic. It is advisable to use alkaline calcium magnesium phosphate fertilizer for the application of phosphate fertilizer. The soils in the north of the country, such as chernozem, chestnut soil, lime-calcium soil, and cinnamon soil, are mostly alkaline. It is advisable to use the slightly acidic superphosphate in the application of phosphate fertilizers; in greenhouses and old vegetable fields that have been continuously fertilized for many years, the gradual acidification tends to occur, and calcium is used. The lack of magnesium, phosphate fertilizer should use alkaline calcium magnesium phosphate fertilizer, phosphate rock, etc., can not only adjust the soil acidity, but also supply calcium and magnesium elements; have salinization characteristics of alkaline earth, saline soil, especially coastal saline soil, can be applied Phosphogypsum, potassium fertilizer should use potassium sulfate. For the selection of fertilizers for plant nutrient characteristics, different types of plants and varieties have different nutrient requirements. The same plant species have different requirements for the amount and proportion of nutrients at different growth stages and different yield levels; different plants have special responses to nutrient types; different plants absorb and utilize nutrients. There are also differences in abilities. Selection of fertilizer varieties should be scientifically selected based on the nutritional characteristics of the crop. According to the research, ammonium nitrogen fertilizer and nitrate nitrogen fertilizer have no significant effect on the nitrate content of vegetables. Generally, the vegetable is a nitrogen-nitrate nitrogen fertilizer, and ammonium nitrate, calcium nitrate, and the like are preferred for the nitrogen fertilizer; and the sulfur fertilizer for the bulbous vegetable may be selected. Sulfur-containing fertilizers, such as superphosphate, magnesium sulfate, and potassium sulfate; cruciferous vegetables are more sensitive to boron, and boron-containing acids such as boric acid and borax should be used; fresh-eating melons such as watermelon , melon and tea are sensitive to chlorine poisoning, generally not suitable for ammonium chloride, potassium chloride and other chlorinated fertilizers; Chinese cabbage, tomatoes, etc. are prone to calcium deficiency symptoms (dried heart, peduncle, etc.), should be used effectively Calcium is more calcium superphosphate and calcium nitrate; fruit, tea requires a lot of organic fertilizer. The fertilizer is selected for the crop growth period, and the absorption of fertilizer is different at different stages of crop growth. Therefore, different fertilizers need to be selected for different growth periods. Fertilizer use neutral high-concentration compound fertilizer, seed dressing fertilizer is generally selected for special-purpose fertilizer; base fertilizer can use low-concentration fertilizer, but also can choose high-concentration compound fertilizer; top-dressing use high-concentration available fertilizers such as urea, diammonium phosphate , Potassium dihydrogen phosphate, etc.; For fertigation and foliar fertilizer application, use high-concentration, easily dissolved, and less residue fertilizers such as urea, ammonium nitrate, potassium dihydrogen phosphate, and a wide variety of organic manures and fertilizers, such as foliar fertilizers. In combination with the use of organic fertilizers, it is even more important to develop sustainable agriculture and the production of pollution-free agricultural products. Studies have shown that organic fertilizers and chemical fertilizers are used in combination to facilitate the renewal of soil organic matter, stimulate the activity of the original humus, increase the substitution of soil cations, help to increase the activity of soil enzymes, and increase the absorption and buffering performance of crops on nutrients. And the stress resistance of crops; it is helpful to coordinate the balance and stability of nitrogen, long-term efficiency, increase the utilization rate of nitrogen, phosphorus, and potassium, and ease the imbalance of fertilizer ratio; it is beneficial to improve the quality of crops, increase the content of nutrients such as protein and amino acids, and reduce vegetables Nitrate and nitrite content in fruits, fruits, etc. Choose a reasonable method of fertilization, nitrate content in vegetables and vegetable types, varieties, different parts related, but also related to fertilizer technology and environmental conditions. In the aspect of breeding, it is meaningful to regard the low nitrate content as one of the breeding objectives; in terms of fertilization techniques and environmental conditions, the nitrate content in vegetables is closely related to the concentration of nitrogen in the soil and the type of nitrogen, and the nitrogen in the soil. The higher the concentration, the higher the nitrate content in vegetables, especially in the later period. Therefore, the application of nitrogen fertilizer should be early, and should not be too much. The development of special-purpose, compound, and special fertilizers, because quality agricultural products require different soil quality and fertilizer, they also need special fertilizers. For example, the production of garlic requires a fertilizer containing higher sulfur, and the production of beer barley requires a reduction in the proportion of nitrogen fertilizer. The ratio of producing 500 kg of rice to 900 kg of rice is different. Japanese fruit trees are generally fertilized for leaf color diagnostic fertilization measures, symptomatic supplement fertilizer. In addition to nitrogen, phosphorus and potassium fertilizers, there are various calcium, magnesium, sulphur fertilizers and trace element fertilizers. The specialization, compounding and diversification of fertilizers are the development trend of fertilizer in the world. In addition, special fertilizers can also be produced to meet human nutrition needs. According to a survey conducted by the Chinese Academy of Sciences, the Ministry of Health, the Department of Geology, and the National Environmental Protection Agency, parts and most of the 22 provinces and cities in China lack selenium, affecting the health of 250 million people. Studies have shown that applying selenium-containing organic compound fertilizer can increase the content of selenium in foods. The selenium-containing organic compound fertilizer was applied to cauliflower, and the selenium content in cauliflower was 0.149 mg/kg, which was 75 times that of ordinary cauliflower containing 0.002 mg/kg selenium. To increase the efficiency of chemical fertilizer use, China’s fertilizer use has reached 42 million tons, accounting for about 30% of the world's total. However, the current fertilizer utilization rate is only about 35%, which is quite different from the world's level of around 45%. Therefore, it is particularly important to improve China's existing fertilizer production structure, improve fertilizer structure, improve fertilization methods, rationally use chemical fertilizers, and increase fertilizer utilization, especially in the current oil crisis.