Abstract:

Nitrogen fertilizers provide the nitrogen necessary for crop growth in modern agricultural production, but their excessive use in the long term leads to waste of resources, economic losses and profound negative environmental impacts. Microorganisms play a critical role in the nitrogen cycle; therefore, there is a significant need for further research in this field. Here, we summarize our findings on the mechanisms and processes by which microorganisms drive the soil nitrogen cycle, including nitrogen fixation, nitrification, denitrification, ammonification, and nitrogen assimilation/dissimilation. We further summarize microbial technologies and strategies for mitigating agricultural nitrogen loss and improving agricultural sustainability, such as nitrogen fixation, greenhouse gas emission reduction, nitrogen bioretention, and ammonia volatilization. These strategies illustrate the potential of microorganisms in reducing the dependence on nitrogen fertilizers and increasing crop yields, while also highlighting the challenges of research and effective field application of these technologies.

Key words: agricultural soils, soil nitrogen cycling, soil nitrogen loss, microbial regulation, nitrogen fertilizer use efficiency