Correct application methods for ammonium-nitrogen compound fertilizer

How should ammonium-nitrogen compound fertilizer be applied? Please give an introduction. There are three types of nitrogen fertilizer in compound fertilizer: ammonium nitrogen, nitrate nitrogen and urea. Nitrate nitrogen is absorbed most quickly by crops, but it is not easily retained in the soil and is prone to leaching with water, so it is best used as a top dressing and less suitable as a base fertilizer; urea also leaches easily, and after being applied to the soil it must undergo transformation before it can be absorbed by crops. This process takes a long time when spring soil temperatures are low, and its effect is too slow, so it is also not ideal as a base fertilizer. Only ammonium nitrogen is both easily adsorbed and retained by the soil, not prone to leaching, and unaffected by low temperatures, giving it the highest utilization rate and making it the most ideal base fertilizer. Therefore, ammonium-nitrogen compound fertilizer is suitable for application as a base fertilizer.