ORIGINAL RESEARCH article
Front. Microbiol.
Sec. Terrestrial Microbiology
Biochar Regulates Putative Keystone Microbial Taxa to Drive Phosphorus Cycling and Increase Availability in Urban Greenspace Soils
Kai Pan 1
Zhenying Zhang 1
Lingwei Feng 1
Xiaogang Wu 1
Xiuyun Yang 1
Xinping He 2
Yiqian Xiao 2
Danning Yang 3
Chengjiao Duan 3,4
Qiang Wang 1
1. Shanxi Agricultural University School of Forestry, Taiyuan, China
2. China Highway Engineering Consultants Corporation, Beijing, China
3. Shanxi Agricultural University College of Resources and Environment, Taiyuan, China
4. State Key Laboratory of Efficient Utilization of Arid and Semi-Arid Arable Land in Northern China, Institute of Agricultural Resources and Regional Planning, Beijing, China
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Abstract
The quality of soil in urban green spaces often deteriorates due to poor design practices, insufficient maintenance, and environmental pressures associated with urbanization. Although biochar, as an effective soil additive, can significantly improve the soil quality in greenspace, it significantly influences the phosphorus (P) cycling processes through functional regulation of microbial community; however, further analysis is essential to validate this mechanism. Therefore, this study reported pot experiments using Euonymus kiautschovicus, a typical urban greenspace plant, followed by metagenomic analysis for investigating microbial-driven P cycle mechanisms. Four treatment groups were established according to the dosage of biochar, including 0% (CK), 4% (BC4), 8% (BC8), and 12% (BC12). Biochar application significantly increased soil available P (AP) and total P (TP) content, with BC12 demonstrating maximum AP and TP content of 21.79 mg kg−1 and 0.62 g kg−1, respectively. On the one hand, biochar serves as a direct source of P. On the other hand, it enhances AP by regulating P‑cycling functional microorganisms. Random forest model identified phnP, phoA, relA, ppnK, pstA, phnD, and pstS as the putative keystone genes regulating soil P cycling. Microbial co-occurrence network analysis and partial least squares path modeling (PLS-PM) demonstrated that the biochar application improved soil AP by regulating putative keystone microbial taxa (Modules 1 and 2) involved in P cycling. This study elucidates the microbial mechanisms underlying biochar-mediated P cycling in greenspace soils, providing a scientific basis for biochar application for improved soil quality in urban greenspace.
Summary
Keywords
biochar, Greenspace soil, Metagenomics, phosphorus cycling, Putative keystone microbial taxa
Received
12 January 2026
Accepted
18 February 2026
Copyright
© 2026 Pan, Zhang, Feng, Wu, Yang, He, Xiao, Yang, Duan and Wang. 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: Qiang Wang
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.