Fungal:Bacterial Ratio

AUS-AKW-AGR-SFB General Low confidence

Benchmark Value

2 ratio
Direction: Higher is desirable ↑
Form: MaximumOnly

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 5 benchmarks together — the OptimalRange form drives the primary score, while 4 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MinimumOnly Guard MaximumOnly Guard OptimalRange Guard OptimalRange Guard

Evidence & Context

An F:B ratio > 2.0 is considered agronomically detrimental for most annual cropping systems.

Metric Definition:

Ratio of fungal to bacterial biomass in soil microbial community.

Benchmark Definition:

This benchmark marks the upper boundary of fungal to bacterial biomass ratio beyond which soil function is mismatched for annual cropping systems in Australia's Arid Karstic Woodlands & Shrublands, indicating agronomic detriment rather than ecological harm.

Justification:

Reflects a functional mismatch where high F:B ratio leads to nutrient immobilization unsuitable for annual crops, not ecological harm.

Sources (1)

Preview of Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed Central, accessed July 18, 2025
Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed Central, accessed July 18, 2025 Journal

Mechanisms and implications of bacterial–fungal competition for soil resources - PMC, accessed July 23, 2025

View Source

Supporting Sources (24)

Additional references from the underlying research that informed this benchmark.

Preview of Analyzing your Fungal to Bacterial Ratio Results - MicroBiometer, accessed July 18, 2025
Analyzing your Fungal to Bacterial Ratio Results - MicroBiometer, accessed July 18, 2025
Methodology Source GreyLiterature

Analyzing your Fungal to Bacterial Ratio Results - microBIOMETER, accessed July 23, 2025

View Source
Preview of Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 23, 2025,
Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 23, 2025,
Contextual Support Journal

FARMER'S TOOLBOX - Panda.org, accessed July 23, 2025,

View Source
Preview of ausveg - fact sheet: soil microbiology, accessed July 18, 2025
ausveg - fact sheet: soil microbiology, accessed July 18, 2025
Contextual Support Journal

ausveg - fact sheet: soil microbiology

View Source
Preview of Biogeographical patterns of the soil fungal:bacterial ratio across France - ASM Journals, accessed July 28, 2025
Biogeographical patterns of the soil fungal:bacterial ratio across France - ASM Journals, accessed July 28, 2025
Contextual Support Journal

Beyond Bacteria: The Importance of Fungi, Protozoa and Nematodes in Soil Microbiology, accessed July 21, 2025

View Source
Preview of Calcareous Soils Initiative - GRDC, accessed July 22, 2025,
Calcareous Soils Initiative - GRDC, accessed July 22, 2025,
Contextual Support Government

Some Characteristics of Calcareous soils. A review A.S. Taalab1, G.W. Ageeb2, Hanan S. Siam1 and Safaa A. Mahmoud1 - CURRENT RESEARCH WEB

View Source
Preview of Climate dictates microbial community composition and diversity in Australian biological soil crusts (biocrusts) - PMC - PubMed Central, accessed July 23, 2025,
Climate dictates microbial community composition and diversity in Australian biological soil crusts (biocrusts) - PMC - PubMed Central, accessed July 23, 2025,
Contextual Support Journal

Assembly and Source of the Lithobiontic Microbial Community in Limestone - MDPI, accessed July 23, 2025,

View Source
Preview of Comparison of methods for assessing fungi-to-bacteria ratio of soil - ResearchGate, accessed on June 5, 2025
Comparison of methods for assessing fungi-to-bacteria ratio of soil - ResearchGate, accessed on June 5, 2025
Methodology Source Journal

Comparison of methods for assessing fungi-to-bacteria ratio of soil - ResearchGate, accessed July 23, 2025,

View Source
Preview of Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization - PMC, accessed July 23, 2025,
Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization - PMC, accessed July 23, 2025,
Contextual Support Journal

Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization - PMC, accessed July 23, 2025,

View Source
Preview of Effects of Semiarid Wheat Agriculture Management Practices on Soil ..., accessed August 5, 2025,
Effects of Semiarid Wheat Agriculture Management Practices on Soil ..., accessed August 5, 2025,
Contextual Support

Effects of Semiarid Wheat Agriculture Management Practices on Soil Microbial Properties: A Review - MDPI, accessed July 23, 2025,

View Source
Preview of Fungal to Bacterial Ratios: What and Why? - Ward Laboratories, Inc., accessed July 18, 2025
Fungal to Bacterial Ratios: What and Why? - Ward Laboratories, Inc., accessed July 18, 2025
Contextual Support Journal

Tagged with ratio of fungi to bacteria - The Prairie Ecologist, accessed July 21, 2025

View Source
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
Contextual Support GreyLiterature

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

View Source
Preview of How microbial C/N and organic C/N ratio relate ? | ResearchGate, accessed July 18, 2025,
How microbial C/N and organic C/N ratio relate ? | ResearchGate, accessed July 18, 2025,
Contextual Support GreyLiterature

How microbial C/N and organic C/N ratio relate ? | ResearchGate

View Source
Preview of Impact of Rocky Desertification Control on Soil Bacterial Community in Karst Graben Basin, Southwestern China - Frontiers, accessed July 23, 2025,
Impact of Rocky Desertification Control on Soil Bacterial Community in Karst Graben Basin, Southwestern China - Frontiers, accessed July 23, 2025,
Contextual Support Journal

Aridity Threshold Induces Abrupt Change of Soil Abundant and Rare Bacterial Biogeography in Dryland Ecosystems - PMC - PubMed Central, accessed July 29, 2025

View Source
Preview of Mechanisms and implications of bacterial–fungal competition for soil resources - PMC, accessed July 18, 2025
Mechanisms and implications of bacterial–fungal competition for soil resources - PMC, accessed July 18, 2025
Contextual Support Journal

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - Frontiers, accessed July 23, 2025

View Source
Preview of Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed August 4, 2025
Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed August 4, 2025
Contextual Support Journal

Regenerative agriculture is key to dry season preparation - Soils For Life, accessed July 23, 2025

View Source
Preview of Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed July 23, 2025,
Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed July 23, 2025,
Contextual Support Journal

Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed July 16, 2025

View Source
Preview of Regenerative Agriculture—A Literature Review on the Practices and ..., accessed July 23, 2025,
Regenerative Agriculture—A Literature Review on the Practices and ..., accessed July 23, 2025,
Contextual Support Journal

Regenerative Agriculture—A Literature Review on the Practices and ..., accessed July 23, 2025,

View Source
Preview of Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 5, 2025,
Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 5, 2025,
Contextual Support Journal

Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed July 20, 2025,

View Source
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 The biogeography of relative abundance of soil fungi versus bacteria in surface topsoil, accessed on June 5, 2025
The biogeography of relative abundance of soil fungi versus bacteria in surface topsoil, accessed on June 5, 2025
Contextual Support Journal

Fungal/bacterial ratios in grasslands with contrasting nitrogen management, accessed July 31, 2025

View Source
Preview of The Biogeography of Soil Bacteria in Australia Exhibits Greater Resistance to Climate Change Than Fungi - PubMed Central, accessed July 23, 2025,
The Biogeography of Soil Bacteria in Australia Exhibits Greater Resistance to Climate Change Than Fungi - PubMed Central, accessed July 23, 2025,
Contextual Support Journal

The Biogeography of Soil Bacteria in Australia Exhibits Greater Resistance to Climate Change Than Fungi - PubMed Central, accessed July 23, 2025,

View Source
Preview of The Biogeography of Soil Bacteria in Australia Exhibits Greater Resistance to Climate Change Than Fungi - PubMed Central, accessed July 28, 2025
The Biogeography of Soil Bacteria in Australia Exhibits Greater Resistance to Climate Change Than Fungi - PubMed Central, accessed July 28, 2025
Contextual Support Journal

Soil and Landscape Grid National Soil Attribute Maps - Soil Bacteria and Fungi Beta Diversity (3" resolution) - Release 1 - Research Data Australia

View Source
Preview of Things you need to know about the Fungal to Bacterial Ratio (F:B) - MicroBiometer, accessed July 28, 2025
Things you need to know about the Fungal to Bacterial Ratio (F:B) - MicroBiometer, accessed July 28, 2025
Contextual Support GreyLiterature

Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed July 23, 2025

View Source
Preview of What are the optimal fungal to bacterial biomass ratios for different crops? - ResearchGate, accessed July 28, 2025
What are the optimal fungal to bacterial biomass ratios for different crops? - ResearchGate, accessed July 28, 2025
Contextual Support GreyLiterature

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon ... - Frontiers, accessed July 21, 2025

View Source

Context

  • Region Australia
  • Biome Arid Karstic Woodlands & Shrublands
  • Land Use Agricultural Crop Production
  • Assessment Conservation Target
  • Evidence Type DegradationThreshold

Lifecycle

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

Notes

This threshold marks the beginning of a soil function mismatch for typical annual and perennial cropping systems, not ecological degradation.

Related Benchmarks

Other benchmarks in the AUS-AKW-AGR-SFB family.

— ratio Low
Agricultural Crop Production · Conservation Target
OptimalRange Active v1
0.3 ratio Low
Agricultural Crop Production · Conservation Target
MinimumOnly Active v1