New review unveils breakthroughs in soil nitrogen cycle research from microbial pathways to global sustainability

A comprehensive review published in Nitrogen Cycling highlights significant advances in understanding the soil nitrogen cycle, emphasizing the critical role of microbial processes and innovative technologies in achieving global nitrogen sustainability.

The study, led by researchers from the Chinese Academy of Sciences, Nanjing Agricultural University, and Zhejiang University, synthesizes a decade of progress in quantifying nitrogen transformation processes, identifying novel microbial pathways, and developing sustainable management strategies.

“Nitrogen is essential for life, but its mismanagement has led to severe environmental issues,” said corresponding author Dr. Xiaoyuan Yan. “Our review bridges the gap between microbial mechanisms and global nitrogen governance, offering science-based solutions for sustainable nitrogen use.”

Key findings include:

• Advanced Methodologies: New techniques such as ¹⁵N tracing models, robotic incubation systems (Robot and Roflow), and membrane inlet mass spectrometry (MIMS) now allow precise measurement of gross nitrogen transformation rates, denitrification, and biological nitrogen fixation (BNF). These tools have revealed unexpected processes, including aerobic nitrogen gas production and the significant role of heterotrophic nitrification.

• Novel Microbial Pathways: The discovery of complete ammonia-oxidizing (comammox) bacteria and direct ammonia oxidation to nitrogen gas (dirammox) has reshaped understanding of nitrification. These microbes operate efficiently under low-nitrogen conditions, offering potential pathways to reduce nitrogen losses and nitrous oxide (N₂​O) emissions.

• Integrated Modeling and Management: Coupled Human and Natural Systems (CHANS) models, combined with remote sensing and artificial intelligence, enable high-resolution tracking of nitrogen flows across scales. Field practices like Integrated Soil-Crop System Management (ISSM) and policy instruments such as Nitrogen Credit Systems (NCS) have demonstrated increased nitrogen use efficiency and reduced environmental impacts.

• Global Implications: The review calls for stronger international cooperation to integrate nitrogen management into global sustainability frameworks, including the Paris Agreement and UN Sustainable Development Goals.

“We are now equipped to not only understand but also manage the nitrogen cycle with unprecedented precision,” said Dr. Yan. “The next step is to translate these insights into actionable strategies that balance agricultural productivity with environmental health.”

The study underscores the need to incorporate microbial processes into large-scale models and policies, enabling targeted interventions that reduce nitrogen pollution while enhancing food security.

=== 

Journal Reference: Yan A, Shan J, Wang X, Wang B, Liu SJ, et al. 2025. Uncovering the soil nitrogen cycle from microbial pathways to global sustainability. Nitrogen Cycling 1: e002 https://www.maxapress.com/article/doi/10.48130/nc-0025-0005 

=== 

About Nitrogen Cycling:
Nitrogen Cycling is a multidisciplinary platform for communicating advances in fundamental and applied research on the nitrogen cycle. It is dedicated to serving as an innovative, efficient, and professional platform for researchers in the field of nitrogen cycling worldwide to deliver findings from this rapidly expanding field of science.

Follow us on Facebook, X, and Bluesky.