The active groups of fulvic acid are generally electron donors, and it is easy to form coordination compounds with many electron acceptors, called complexes or chelates. For example, fulvic acid-urea, etc., are actually complex (chelated) substances, which can reduce the loss of ammonium nitrogen and increase the utilization rate of nitrogen fertilizer. The oxidatively degraded nitro fulvic acid can inhibit urease activity and reduce urea volatilization.

Adding fulvic acid to ammonium bicarbonate can reduce the nitrogen volatilization rate of ammonium bicarbonate from 13.1% to 2.04% in 6 days. In the farm field test, the effect of ammonium bicarbonate was maintained for more than 20 days, and the ammonium fulvic acid could reach more than 60 days. Adding fulvic acid, especially nitro fulvic acid, to urea can generate urea complex, which slows down the decomposition of urea, prolongs the fertilizer efficiency, and reduces the loss. The utilization rate of urea is relatively increased by 30% and the aftereffect is increased by more than 15%. As a result of the determination of nitrogen utilization rate, the utilization rate increased from 30.1% to 34.1% after adding fulvic acid, and the nitrogen absorption increased by 10%.

The effect of fulvic acid combined with nitrogen on plant growth and development is very obvious. When nitrogen and fulvic acid are sufficient, plants can synthesize more protein to promote cell division and growth. Therefore, the leaf area of plants grows quickly, and more leaf area can be used for photosynthesis. It has obvious effect on promoting the growth of plants. Often after application, the leaf color turns green quickly and the growth increases.