Fungal:Bacterial Ratio

AUS-TMI-FOR-SFB General Low confidence

Benchmark Value

1 index
Direction: Higher is desirable ↑
Form: MinimumOnly

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context. The scoring engine uses 6 benchmarks together — the OptimalRange form drives the primary score, while 5 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MinimumOnly Guard OptimalRange Guard MinimumOnly Guard OptimalRange Guard MinimumOnly Guard

Evidence & Context

Therefore, an F:B ratio approaching or falling below 1.0 can be confidently established as a lower critical threshold.

Metric Definition:

Fungal to bacterial biomass ratio in soil

Benchmark Definition:

This benchmark defines the lower critical threshold for fungal to bacterial biomass ratio in soil, below which the microbial community is considered disturbed and indicative of degraded soil function in production forestry.

Justification:

An F:B ratio below 1.0 indicates a highly disturbed, bacterially-dominated system with compromised ecological function, representing management failure in sustainable production forestry.

Sources (1)

Preview of Bailey VL, Smith JL, Bolton H Jr.. Fungal-to-bacterial ratios in soils investigated for enhanced C sequestration. Soil Bio Biochem 34: 997-1007 | Request PDF - ResearchGate, accessed on June 5, 2025
Bailey VL, Smith JL, Bolton H Jr.. Fungal-to-bacterial ratios in soils investigated for enhanced C sequestration. Soil Bio Biochem 34: 997-1007 | Request PDF - ResearchGate, accessed on June 5, 2025 Journal

Bailey VL, Smith JL, Bolton H Jr.. Fungal-to-bacterial ratios in soils investigated for enhanced C sequestration. Soil Bio Biochem 34: 997-1007 | Request PDF - ResearchGate

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Supporting Sources (7)

Additional references from the underlying research that informed this benchmark.

Preview of Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed Central, accessed August 1, 2025
Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed Central, accessed August 1, 2025
Cross Reference Journal

Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed Central, accessed August 1, 2025

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Preview of Fungi to bacteria ratio: Historical misinterpretations and potential implications | Request PDF, accessed July 18, 2025
Fungi to bacteria ratio: Historical misinterpretations and potential implications | Request PDF, accessed July 18, 2025
Contextual Support Journal

Mechanisms and implications of bacterial–fungal competition for soil resources - PMC, accessed July 21, 2025

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Preview of Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon ... - Frontiers, accessed July 18, 2025
Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon ... - Frontiers, accessed July 18, 2025
Contextual Support Journal

How Biodiversity-Friendly Is Regenerative Grazing? - Frontiers

View Source
Preview of Soil organic matter and geochemical characteristics shape microbial community composition and structure across different land uses in an Australian wet tropical catchment | Request PDF - ResearchGate, accessed August 1, 2025
Soil organic matter and geochemical characteristics shape microbial community composition and structure across different land uses in an Australian wet tropical catchment | Request PDF - ResearchGate, accessed August 1, 2025
Contextual Support Journal

Soil organic matter and geochemical characteristics shape microbial community composition and structure across different land uses in an Australian wet tropical catchment | Request PDF - ResearchGate, accessed August 1, 2025

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Preview of Srivastava, S. C., & Singh, J. S. (1989). Effect of cultivation on microbial biomass C and N of a dry tropical forest soil. Biology and Fertility of Soils, 8(4), 343-348.
Srivastava, S. C., & Singh, J. S. (1989). Effect of cultivation on microbial biomass C and N of a dry tropical forest soil. Biology and Fertility of Soils, 8(4), 343-348.
Direct Evidence GreyLiterature

Soil microbial biomass, activity and community composition in adjacent native and plantation forests of subtropical Australia | Request PDF - ResearchGate

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Preview of Synthesis based on Burton et al. (2007), Paul et al. (2020), and global patterns from Shi et al. (2022)
Synthesis based on Burton et al. (2007), Paul et al. (2020), and global patterns from Shi et al. (2022)
Direct Evidence

Synthesis based on Burton et al. (2007), Paul et al. (2020), and global patterns from Shi et al. (2022)

View Source
Preview of Urbanization and edge effects interact to drive mutualism breakdown and the rise of unstable pathogenic communities in forest soil | PNAS, accessed August 1, 2025
Urbanization and edge effects interact to drive mutualism breakdown and the rise of unstable pathogenic communities in forest soil | PNAS, accessed August 1, 2025
Contextual Support Journal

Urbanization and edge effects interact to drive mutualism breakdown and the rise of unstable pathogenic communities in forest soil | PNAS, accessed August 1, 2025

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Production Forestry
  • Assessment Not Stated
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 8 Jun 2026

Notes

This threshold is based on consistent evidence from intensively managed and frequently disturbed systems such as conventional agriculture with regular tillage. No upper detrimental threshold — higher values are always better up to natural saturation. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TMI-FOR-SFB family.

— index Low
Production Forestry · Not Stated
OptimalRange Active v1