Development and application of film mulched contro

Japan develops and applies film mulched controlled-release fertilizers

when the supply intensity of nutrient elements in the soil cannot meet the realization of crop production goals, it is necessary to artificially apply human beings directly to the soil or supplement the nutrient elements lacking in crop growth and development. The main way to supplement the lack of nutrients in crops is to apply quick acting chemical fertilizers to the soil. The research shows that this method of fertilization has many shortcomings: first, the utilization rate of nutrients is not high. Studies have shown that the seasonal utilization rate of chemical fertilizer in China. The nitrogen strain extensometer is composed of elastic elements and strain gauges pasted on it. The fertilizer is 30% - 35%, the phosphorus fertilizer is 10% - 25%, and the potassium fertilizer is 35% - 50%. Most of the nutrients in the soil are leached, volatilized and fixed. Second, this kind of fertilization analyzes the index mode that should be paid special attention to when selecting the tensile machine for soft packaging material detection, which is easy to pollute the environment. Taking nitrogen fertilizer as an example, long-term large-dose application of nitrogen fertilizer to soil will increase the nitrogen content of soil and groundwater, resulting in soil acidification and salinization, and nutrient enrichment of rivers and lakes. In addition, under the condition of denitrification, a large amount of nitrogen application produces N2O, which volatilizes into the atmosphere, destroys the ozone layer, and intensifies the greenhouse effect. Third, crops are vulnerable to diseases and pests. After a large number of quick acting fertilizers are used, crops will grow luxuriantly in a short period of time, with juicy leaves, weakened resistance, and serious diseases and pests. In order to prevent and control diseases and pests, applying pesticides not only increases the production cost, but also pollutes the environment. Fourth, the one-time application of quick acting fertilizer can not meet the needs of the growth of crops in the whole growth period. It grows fast in the early stage of growth, and appears the phenomenon of de fertilization in the late stage. Topdressing also increases the labor intensity and cost. For this reason, scientists from all over the world are actively developing various slow-release or controlled-release fertilizers, which can provide stable nutrition to crops on the one hand, and reduce the loss of fertilizers and environmental pollution on the other hand

I. Development of film coated controlled-release fertilizer

Japan successfully developed controlled-release fertilizer in the 1980s. After continuous improvement, the product has become a commercial fertilizer and is sold on the international market. The international trade names are Meister and nutricote. The controlled-release fertilizer in Japan is made of polyene resin as the main body, with different proportions of surfactants and additives wrapped on the surface of the fertilizer. This film coated fertilizer has certain permeability to water, resists certain pressure, and is conducive to machine application. Film covered controlled-release fertilizer can be divided into many day types (the day type is the number of days when the controlled-release fertilizer releases 80% of its nutrients in 25 ℃ water), mainly 30, 40, 50, 70, 100, 140, 180, 360, and the nutrients include n, NP, NPK, NCA, NPK and other trace elements. Different daily fertilizers can be applied alone or in combination to meet the needs of different crops' growth and development

there are two main categories of film coated controlled-release fertilizers: one is the ordinary release group, and the other is the delayed release group. The nutrient release law of the ordinary release type follows the quadratic 11. Fixture program, while the nutrient release law of the delayed release type follows the S-shaped curve

the nutrient release of the film coated controlled-release fertilizer is mainly controlled by the soil temperature. The soil temperature is high, the nutrient release is fast, the temperature is low, and the nutrient release is slow. The release of nutrients is not affected by soil water content (within the normal physiological metabolism range of crops), soil pH, eh and cation and anion ions, otherwise it is easy to cause the scraping operation and numbering of the material layer, and the scraping mold is mainly to scrape off the excess content. This characteristic of film covered controlled-release fertilizer ensures that the release of nutrients can coincide with the growth and development period of crops. It can be used as a base fertilizer, which can be used at one time. It not only saves labor, improves the utilization rate of fertilizer, but also meets the needs of crop growth in the whole growth period

2. Application of film mulched controlled-release fertilizer in agricultural production

1. Rice seedbed full fertilization technology is to apply all the nutrients required for the whole growth period of rice to the seedbed. With the transplanting of seedlings, the root system wraps the controlled-release fertilizer applied to the seedbed and transplants it to the field together; The results showed that when the delayed release urea lp-s100 (containing 40% nitrogen) was applied to the rice seedbed, under the condition of 25 ℃ ground temperature, the initial 30 day release amount was very small, only 3%; 80% of nitrogen was released in the following 70 days. In this way, rice seeds will not produce fertilizer damage in the seedbed and will not cause excessive growth in the seedling stage. After transplanting to Honda, with the increase of accumulated ground temperature, nitrogen release is consistent with the growth process of rice, and topdressing during the growth period is not required. The amount of nitrogen fertilizer used in this method is only 60% of the conventional amount, and the yield is more than 10% higher than that of the conventional method. The technology of full fertilization in rice per mu bed has a broad application prospect in rice no tillage cultivation

2. The same layer fertilization technology of field crop seeds and fertilizers. When sowing crops, seeds and film covered controlled-release fertilizers can be applied in the same layer. In terms of fertilizer amount and fertilizer type, according to the fertilizer demand law of different crops and combined with local meteorological data, different types of fertilizers are selected for combined application, which not only meets the needs of seedling stage, but also meets the needs of crop growth in the later stage. This technology has a good effect in seedling raising, transplanting and no tillage cultivation of corn and sugar beet

3. The application of soilless culture in Supreme cultivation has many advantages, but because the cultivation nutrient solution needs to be regularly adjusted for acidity and ion concentration, the operation is more complex, which limits its rapid development. The application of film covered controlled-release fertilizer only needs to mix the fertilizer containing various nutrient elements with the cultivation matrix, and regularly supply the water required for plant growth. The various nutrient elements contained in the fertilizer will be continuously released according to the growth process of plants, so as to meet the needs of the growth and development of cultivated plants, reduce the labor intensity, and make soilless cultivation technology a simple and popular production technology