In the pursuit of efficient and environmentally friendly modern agricultural development, controlled-release fertilizers, with their unique advantages, are gradually becoming the new favorite in the fertilizer market. This type of fertilizer not only enhances the utilization rate of fertilizers, reduces environmental pollution, but also promotes the healthy growth of crops, injecting new vitality into sustainable agricultural development.
Controlled-release fertilizers, also known as CRF, are an advanced form of slow-release fertilizers. They control the release rate of nutrients in the fertilizer through coating technology, encapsulation, and the addition of inhibitors, ensuring that the nutrient release aligns with the nutrient demand of crops during their growth cycle. This achieves the goals of long-lasting and efficient effects. Controlled-release fertilizers represent the main direction of modern fertilizer development, are particularly suitable for mechanized production, and especially meet the requirements of simultaneous seeding and fertilization.
The micro-pores on the membrane of controlled-release fertilizers are usually only a few hundred nanometers in size, and liquid water cannot pass through directly. Only water molecules can enter the membrane. Therefore, apart from water molecules being able to freely enter and exit the membrane, the fertilizer particles are completely isolated from the outside. The rate of nutrient release is only related to the movement speed of water molecules and the pore size of the membrane micro-pores, and the movement speed of water molecules depends on the temperature. This makes the nutrient release curve of controlled-release fertilizers match the plant demand curve, achieving supply on demand.
Compared with traditional fertilizers, controlled-release fertilizers have significant advantages. Firstly, they have a high fertilizer efficiency utilization rate. Conventional fertilizers suffer from severe nutrient loss, with less than 30% of the nutrients being utilized by crops. In contrast, controlled-release fertilizers control nutrient release through coating, preventing nutrient loss and achieving a fertilizer efficiency utilization rate of over 70%, and even over 80% when used near the roots. Secondly, controlled-release fertilizers have a remarkable yield-increasing effect. By regulating nutrient release, they ensure a stable and regular supply of nutrients to crops, avoiding nutrient deficiency and excessive growth, thereby achieving a significant increase in yield.
In addition, controlled-release fertilizers have multiple advantages such as saving time and effort, killing bacteria and repelling pests, improving soil quality, and supplementing sulfur for crops. The use of controlled-release fertilizers can significantly reduce the frequency of fertilization and save human and material resources. Meanwhile, the coating material of controlled-release fertilizers is made of polysulfide compounds, which have the effect of killing bacteria and repelling pests, reducing the use of pesticides. After the nutrients are released, the empty shells can retain water and moisture, providing aeration and nutrient retention functions, improving soil structure and making long-term compacted soil loose. Furthermore, the empty shells of controlled-release fertilizers can be directly broken down and participate in nutrient release after being absorbed by crops, providing necessary sulfur elements for crops.
