The Importance of Scientific Use of Nitrogen Fertilizer

Using nitrogen fertilizer unscientifically can lead to a series of problems in crop growth. For example, over - fertilization may cause excessive vegetative growth of crops, making them more susceptible to pests and diseases, and reducing their resistance to adverse environmental conditions. On the contrary, under - fertilization can result in stunted growth, yellowing leaves, and low yields. Therefore, mastering the scientific use of nitrogen fertilizer is of great significance for promoting crop health and increasing yields.

Determining Nitrogen Fertilizer Dosage Based on Soil Fertility

Soil fertility varies greatly in different regions. Generally, soils can be divided into three categories: high - fertility, medium - fertility, and low - fertility. For high - fertility soils, the nitrogen fertilizer requirement is relatively low. According to agricultural experts, for high - fertility farmland, the recommended nitrogen fertilizer application rate is about 10 - 15 kg per mu. In medium - fertility soils, the application rate can be increased to 15 - 20 kg per mu. And for low - fertility soils, it may need 20 - 25 kg per mu.

The following table shows the comparison of nitrogen fertilizer usage in different soil fertility:

Fertilization Methods

Combining Base Fertilizer and Top - dressing

Applying base fertilizer before sowing can provide a long - term supply of nutrients for crops. Usually, about 40% - 60% of the total nitrogen fertilizer can be used as base fertilizer. Then, top - dressing at the critical growth stages of crops, such as the tillering stage and the jointing stage, can meet the sudden increase in nutrient demand. For example, in wheat cultivation, applying 50% of the nitrogen fertilizer as base fertilizer and the remaining 50% as top - dressing during the jointing stage can significantly improve the yield and quality of wheat.

Fertilization Depth

The appropriate fertilization depth is also crucial. Nitrogen fertilizers are best applied at a depth of 8 - 12 cm. This can prevent nitrogen loss through volatilization and runoff, and ensure that the roots of crops can effectively absorb nutrients. For example, when using ammonium - based nitrogen fertilizers, if they are applied too shallowly, a large amount of ammonia may volatilize, reducing the fertilizer efficiency.

Application Methods of Different Nitrogen Fertilizer Varieties

Different nitrogen fertilizer varieties have different characteristics. For example, urea is a slow - release nitrogen fertilizer. It needs to be converted into ammonium nitrogen by soil microorganisms before it can be absorbed by crops. Therefore, it is best to apply urea 3 - 5 days in advance. Ammonium sulfate is a quick - acting nitrogen fertilizer, which can be directly absorbed by crops. It is suitable for top - dressing during the rapid growth period of crops.

Real - world Case

In a certain farm in the Midwest, farmers used to apply nitrogen fertilizer blindly. The yield of corn was not high, and the quality was also poor. After consulting agricultural experts, they began to determine the nitrogen fertilizer dosage according to the soil fertility, adopted the method of combining base fertilizer and top - dressing, and adjusted the fertilization depth. As a result, the corn yield increased by 20% compared with the previous year, and the quality also improved significantly.

Conclusion

Using nitrogen fertilizer scientifically can not only improve the utilization rate of fertilizers, reduce costs, but also promote the healthy growth of crops, increase yields, and improve quality. It is a win - win strategy for both farmers and the environment. We encourage farmers to put these scientific fertilization methods into practice and experience the benefits they bring.

Now, let's have an interactive question: If your farmland has medium - fertility soil, and you are planting rice, how much nitrogen fertilizer would you apply according to the above - mentioned knowledge? Leave your answer in the comments below!

For more in - depth knowledge about scientific fertilization, feel free to contact us. We are here to provide you with professional guidance and support.