The nitrogen utilization efficiency of several main nitrogen fertilizers are: 25% or 30% ammonium bicarbonate, 30% or 35% urea, and 35%-40% ammonium sulfate. At present, the average utilization rate of nitrogen fertilizer in my country is 35%.

The main reasons for the low utilization rate of nitrogen in China are as follows:

Nutrient loss

Too much fertilizer

Improper nutrient distribution

In general, the utilization rate of nitrogen fertilizer can be moderately improved which can start from the following two aspects.

From the perspective of agronomy, it can be taken: 1) Deep application of soil; 2) Formulated fertilization; 3) Combination of water and fertilizer, etc. These measures can improve fertilizer utilization.

From the aspect of technology, it can be adopted: 1) modification of ammonium bicarbonate to produce long-term ammonium bicarbonate; 2) using coating technology to produce coated urea; 3) production of controllable and slow-release urea, etc. These measures can greatly improve the utilization of nitrogen fertilizer by 10-30 percentage higher.

This is my viewpoint. Hope it can help. Thanks.

Thank you Qin for your valuable feebdack!!

In addition to the above mentioned nitrogen use efficiency of mineral fertilizers you may consider the benefits of legums (biological nitrogen fixation) and related pre-crop effects (see Article Magnitude and farm-economic value of grain legume pre-crop b...

Nitrogen use efficiency (NUE) is just one indicator.

Environmental sustainability requires a combination of multiple indicators to make a reasonable evaluation.

It takes at least 3 years of field trials to show how good the effect of reducing nitrogen fertilisation is.

In addition to NUE, the main evaluation indicators mainly include whether the yield and quality of crops have declined during these years? Has the soil's nitrogen supply capacity been exhausted?