Nitrogen fertilizer is a fertilizer containing nitrogen in crop nutrient elements. Elemental nitrogen plays an important role in crop growth, which is part of the amino acids in plants, components of proteins, and part of chlorophyll, which determines the photosynthetic effects of plants. Nitrogen can also help crops to colonize, and applying nitrogen fertilizer can not only increase the yield of agricultural products, but also improve the quality of agricultural products. Nitrogen fertilizer is also a kind of inorganic salts.