Fungal:Bacterial Ratio

AUS-TDG-CON-SFB General Moderate confidence

Benchmark Value

No specific value — see range
Range: 5 to 12 ratio
Optimal Range: 5 to 12
Direction: Higher is desirable ↑
Form: OptimalRange

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.

Evidence & Context

In our project, fungal to bacterial ratio is expressed as a scale, with numbers less than 5 showing a large imbalance, while numbers greater than 5 and below 12 indicate a good balance.

Metric Definition:

Colorimetric microBIOMETER assay scale determining active fungal to bacterial biomass carbon ratio in topsoil.

Benchmark Definition:

Healthy fungal to bacterial ratio range indicating good biological balance in undisturbed forest or native bushland ecosystems.

Justification:

This scale represents reference biological standards established by a major Australian soil diagnostics laboratory for undisturbed, structurally complex native forest and bushland soils.

Sources (1)

Preview of Unlocking the power of microbes to enhance the soil
Unlocking the power of microbes to enhance the soil GreyLiterature

Unlocking the power of microbes to enhance the soil

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Supporting Sources (7)

Additional references from the underlying research that informed this benchmark.

Preview of Different responses of soil fungal and bacterial communities to nitrogen addition in a forest grassland ecotone - Frontiers
Different responses of soil fungal and bacterial communities to nitrogen addition in a forest grassland ecotone - Frontiers
Direct Evidence Journal

Soil microbiology factsheet

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Preview of Fungal/bacterial ratios in grasslands with contrasting nitrogen ...
Fungal/bacterial ratios in grasslands with contrasting nitrogen ...
Direct Evidence

Fungal/bacterial ratios in grasslands with contrasting nitrogen ...

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Preview of Fungal/bacterial ratios in grasslands with contrasting nitrogen management - ResearchGate, accessed July 18, 2025
Fungal/bacterial ratios in grasslands with contrasting nitrogen management - ResearchGate, accessed July 18, 2025
Direct Evidence GreyLiterature

Fungal/bacterial ratios in grasslands with contrasting nitrogen management - ResearchGate

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Preview of Fungus and bacteria OH MY!! F:B Ratios explained - Mass Hydroponics
Fungus and bacteria OH MY!! F:B Ratios explained - Mass Hydroponics
Contextual Support GreyLiterature

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - PMC - PubMed Central, accessed July 21, 2025

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Preview of Global biogeography of fungal and bacterial biomass carbon in topsoil
Global biogeography of fungal and bacterial biomass carbon in topsoil
Irrelevant

Biogeographic patterns of soil bacterial and fungal biomass C and their ratios across major biomes

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Preview of Response of soil microbial functionality and soil properties to ...
Response of soil microbial functionality and soil properties to ...
Contextual Support Journal

Pastures to woodlands: Changes in soil microbial communities and carbon following reforestation | Request PDF - ResearchGate

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Preview of Role of Soil Fungus | Ohioline - The Ohio State University, accessed on June 5, 2025
Role of Soil Fungus | Ohioline - The Ohio State University, accessed on June 5, 2025
Contextual Support GreyLiterature

Role of Soil Fungus | Ohioline - The Ohio State University, accessed on June 7, 2025,

View Source

Context

  • Region Australia
  • Biome Temperate Dry Woodlands & Native Grasslands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Vegetation Forest
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 19 Jun 2026

Notes

Colorimetric testing provides a rapid, cost-effective surrogate that correlates with laboratory-grade direct counts and molecular biomass assays.