Skip to main content

ORIGINAL RESEARCH article

Front. Microbiol.
Sec. Terrestrial Microbiology
Volume 15 - 2024 | doi: 10.3389/fmicb.2024.1523084
This article is part of the Research Topic Soil Carbon Sequestration and Microbial Energy Metabolism View all articles

Iron-oxidizing microorganisms affect the iron-bound organic carbon in the subsoil of alpine grassland during the thawing of seasonal frozen soil

Provisionally accepted
Yuxin Tian Yuxin Tian Maidinuer Abulaizi Maidinuer Abulaizi *Zailei Yang Zailei Yang *Tianle Kou Tianle Kou *Yuanbin Jia Yuanbin Jia *Yunpeng Hu Yunpeng Hu *Mo Chen Mo Chen *Jia Hongtao Jia Hongtao *
  • Xinjiang Agricultural University, Ürümqi, China

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

    Iron (Fe) minerals possess a huge specific surface area and high adsorption affinity, usually considered as "rust tanks" of organic carbon (OC), playing an important role in global carbon storage. Microorganisms can change the chemical form of Fe by producing Fe chelating agents such as side chains, and form a stable complex with Fe(III), which makes it easier for microorganisms to use. However, in the process of seasonal frozen soil thawing, the succession of soil Fe cycling microbial community and its coupling relationship with Fe oxides and Fe-bound organic carbon (Fe-OC) are unclear. We characterized changes in the Fe phase, Fe-OC, Fe-oxidizing bacteria (FeOB), and Fe-reducing bacteria (FeRB) in the subsoil and analyzed the microbial mechanism underlying Fe-OC changes in alpine grassland by constructing a composite structural equation model (SEM). We found that the Fe(III) content consistently exceeded that of Fe(II). Among three types of Fe oxides, organically complex Fe (Fep) decreased from 2.54 to 2.30 g•kg -1 , whereas the opposite trend was observed for poorly crystalline Fe (Feo). The Fe-OC content also decreased (from 10.31 to 9.47 g•kg -1 ) (P < 0.05). Fe-cycling microorganisms were markedly affected by the thawing of frozen soil (with the exception of FeRB). Fep and Feo directly affected changes in Fe-OC. Soil moisture (SM) and FeOB were significant indirect factors affecting Fe-OC changes. Freeze-thaw changes in the subsoil of alpine grassland in Central Asia significantly affected FeOB and Fe oxides, thus affecting the Fe-OC content. As far as we know, this is the first study examining the influence of Fe-cycling microorganisms on the Fe phase and Fe-OC in the soil of alpine grassland in Central Asia. Overall, our findings provide scientific clues for exploring the biogeochemical cycle process in future climate change.

    Keywords: Alpine grassland, Thawing of seasonal frozen soil, Fe-cycling microorganisms, Febound organic carbon, Fe-cycling functional genes

    Received: 05 Nov 2024; Accepted: 12 Dec 2024.

    Copyright: © 2024 Tian, Abulaizi, Yang, Kou, Jia, Hu, Chen and Hongtao. 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:
    Maidinuer Abulaizi, Xinjiang Agricultural University, Ürümqi, China
    Zailei Yang, Xinjiang Agricultural University, Ürümqi, China
    Tianle Kou, Xinjiang Agricultural University, Ürümqi, China
    Yuanbin Jia, Xinjiang Agricultural University, Ürümqi, China
    Yunpeng Hu, Xinjiang Agricultural University, Ürümqi, China
    Mo Chen, Xinjiang Agricultural University, Ürümqi, China
    Jia Hongtao, Xinjiang Agricultural University, Ürümqi, China

    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.