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Updated: May 23, 2026
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Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside
Published on: July 3, 2016
Freeze-thaw strength regulates carbon density through microbial assembly processes and network clustering
Shengyun Chen1,2, Enyan Liu2, Yuzheng Gu1
1Cryosphere and Eco-Environment Research Station of Shule River Headwaters, State Key Laboratory of Cryospheric Science and Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.
Msystems
|May 22, 2026
Summary
Seasonal freeze-thaw cycles in permafrost soils significantly impact microbial communities and carbon storage. Understanding these microbial responses is crucial for predicting carbon sequestration under climate warming.
Area of Science:
- Environmental Science
- Microbiology
- Soil Science
Background:
- Freeze-thaw cycles are key drivers of soil carbon dynamics, particularly in permafrost regions.
- The specific mechanisms linking freeze-thaw patterns to microbial community structure and carbon sequestration remain poorly understood.
- Climate warming is intensifying freeze-thaw cycles in permafrost, necessitating research into microbial responses.
Purpose of the Study:
- To investigate how seasonal freeze-thaw processes regulate microbial communities and carbon storage in alpine permafrost.
- To analyze the impact of freeze-thaw on microbial community composition, diversity, assembly, and network structure.
- To determine the relationship between microbial properties and water-soluble organic carbon density (WSOCD).
Main Methods:
- Conducted in situ investigations across four seasonal freeze-thaw periods (thawing, thawed, freezing, frozen) in the Qinghai-Tibet Plateau.
- Analyzed microbial community composition, beta diversity, and assembly processes (drift, dispersal limitation).
- Examined microbial co-occurrence networks and their association with water-soluble organic carbon density (WSOCD).
Main Results:
- Species turnover was the primary driver of microbial beta diversity during seasonal freeze-thaw.
- Stochastic processes, particularly bacterial drift and fungal dispersal limitation, dominated microbial assembly.
- Microbial network clusters, influenced by phylogenetic groups, showed a negative correlation with WSOCD.
- Freeze-thaw strength explained 37% of WSOCD variation by altering soil and microbial properties.
Conclusions:
- Seasonal freeze-thaw processes significantly influence microbial community assembly and structure in alpine permafrost.
- Microbial community properties are closely linked to active carbon storage, impacting WSOCD.
- Findings offer insights into microbially mediated carbon dynamics and predicting carbon sequestration under future warming scenarios.
Keywords:
community assemblyfreeze-thaw strengthmicrobial beta diversitynetwork clusterswater-soluble organic carbon densityMore Related Videos
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