At present, the utilization rate of fertilizers in China is relatively low. The current utilization rate of nitrogen fertilizers is only 30% to 40%. There are three destinations after nitrogen fertilizers are applied to the soil. First, it is absorbed by the crops of the season (generally 30 to 40%); second It is left in the soil (25 to 35%); the third is to leave the soil and lose crops (20 to 60%). The current utilization rate of phosphate fertilizer is 10-25%, and the utilization rate of potassium fertilizer is 50-60%. So how do we increase the utilization rate of fertilizers?
1. Fertilize according to locality and crops. According to the soil's fertilization capacity, PH value and the characteristics of crops' demand for fertilizers, the amount and variety of fertilizers should be reasonably determined. Such as legume crops, cotton, melons and fruit trees are phosphorus-loving crops, and the application of phosphorus fertilizer has better fertilizer effect.
2. The mixed use of nitrogen, phosphorus, potassium and organic fertilizer. According to experiments on wheat, the combined application of nitrogen, phosphorus and potassium increased the yield by 16.5% than the single application of phosphorus, the yield was increased by 10.5% than the single application of nitrogen, and the yield by 6.4%. Moreover, the mixed use with organic fertilizer can also reduce the adsorption and fixation of phosphorus by the soil, and improve the utilization rate of phosphate fertilizer.
3. Deep, concentrated and layered application. Deep application is an important way to improve the utilization rate of nitrogen fertilizer and reduce the loss of nitrogen fertilizer. It can not only reduce the volatilization of ammonia, but also reduce the loss of denitrification; the centralized application of phosphate fertilizer can reduce the contact surface between the fertilizer and the soil, reduce the chemical fixation, and In addition, the concentration difference between the root system and the crop root system can be increased to promote the absorption of phosphorus by crops. In addition, phosphorus has poor mobility in the soil. Layered application can meet the needs of phosphorus in different growth periods.
4. Use in time. The critical period and maximum efficiency period of crops are the two key periods for crops to absorb nutrients. These two periods should be grasped to ensure the maximum efficiency of fertilizers and the demand of crops for nutrients. Generally, the critical nutrition period of phosphorus is in the early stage of growth, and nitrogen is slightly later than phosphorus in the critical nutrition period. The maximum efficiency period is the period when vegetative growth is transformed into reproductive growth.
5. Strengthen water management. The supply of water is closely related to the absorption of crop nutrients. Improper use of water not only causes nutrient loss, but also affects the growth of crops. Appropriate irrigation can improve the utilization rate of fertilizers, but too much or too little will reduce the utilization rate.
6. Foliar spray fertilizer. Foliar spraying of crops can not only meet the crop's nutrient requirements in time, but also reduce the soil's fixation of nutrients and improve fertilizer utilization.
7. Formula fertilization. Formula fertilization technology can improve the utilization rate of chemical fertilizer by 5% to 10%, and can also avoid blind fertilization and reduce fertilizer waste. From the absolute value, the amount of nitrogen absorbed by the crop, the amount of residue in the soil and the amount of fertilizer lost increase with the increase of the amount of nitrogen fertilizer; from the relative value, the utilization rate of nitrogen fertilizer decreases with the increase of the amount of fertilizer, the loss rate With the increase in the amount of fertilization increased.