Your new experience awaits. Try the new design now and help us make it even better

ORIGINAL RESEARCH article

Front. Microbiol.

Sec. Terrestrial Microbiology

This article is part of the Research TopicMicrobe-Environment Interaction Across Grassland Ecosystems: Soil Microbial Diversity, Plant-Microbe Interplay, and Ecosystem FunctionalityView all 13 articles

Nitrogen Addition has Negative Effects on Bacterial Diversity and Stability, But Simulated Grazing Mitigates these Effects

Provisionally accepted
Zeyu  LiuZeyu LiuYiqiang  DongYiqiang Dong*An Jing  JiangAn Jing JiangZongjiu  SunZongjiu SunYue  WuYue WuYaxin  LeiYaxin LeiXingyun  ShanXingyun ShanKai  WuKai Wu
  • Xinjiang Agricultural University, Ürümqi, China

The final, formatted version of the article will be published soon.

Nitrogen addition and grazing, as common management tools in grasslands, alter the structure and function of soil microbial communities and have far-reaching effects on grassland ecosystems. However, the mechanisms by which nitrogen addition and grazing regulate the diversity and stability of soil microbial communities remain insufficiently understood. In this study, a field experiment was conducted in the temperate desert grassland of Xinjiang, combining nitrogen addition treatments with simulated grazing to investigate the response mechanisms of soil microbial communities to nitrogen addition and simulated grazing. The regulation of soil microbial community diversity and stability under the combined effects of nitrogen addition and grazing was examined by using mowing to simulate aboveground vegetation disturbance. The results showed that inorganic nitrogen (nitrate and ammonium nitrogen) was a key factor driving nitrogen-induced changes in microbial community structure, increasing the availability of soil nitrogen. Moderate nitrogen addition promoted bacterial community diversity, whereas excessive nitrogen input weakened this effect and reduced bacterial community complexity and co-occurrence network stability. Simulated grazing enhanced organic nitrogen catabolism through increased leucine aminopeptidase activity, thereby stabilizing bacterial community interactions under nitrogen-enriched conditions and alleviating the negative effects of nitrogen addition. These results indicate that grazing can buffer nitrogen-induced destabilization of soil microbial communities and highlight its role in maintaining microbial functional stability in grassland ecosystems under increasing nitrogen deposition.

Keywords: grassland, Microbial co-occurrence network, Microbial Diversity, Nitrogen addition, simulated grazing

Received: 15 Nov 2025; Accepted: 30 Jan 2026.

Copyright: © 2026 Liu, Dong, Jiang, Sun, Wu, Lei, Shan and Wu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Yiqiang Dong

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.