Fungal:Bacterial Ratio

AUS-AIF-CON-SFB General Moderate confidence

Benchmark Value

0.15 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 9 benchmarks together — the OptimalRange form drives the primary score, while 8 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

An F:B ratio of < 0.15 should be viewed as a management trigger, prompting investigation into potential stressors and indicating that the system's capacity for nutrient retention and long-term stability may be compromised.

Metric Definition:

Fungal:Bacterial Ratio critical lower threshold indicating potential ecosystem degradation when below this value.

Benchmark Definition:

This benchmark defines a critical lower threshold for the fungal to bacterial biomass ratio in soil, below which ecosystem function is likely impaired in arid inland floodplains under conservation management.

Justification:

Based on analogue data where values below 0.15 indicate a shift towards degraded, bacterially-dominated systems, this threshold prompts management investigation.

Sources (1)

Preview of Biochemical properties of highly mineralised and infertile soil modified by acacia and spinifex plants in northwest Queensland, Australia
Biochemical properties of highly mineralised and infertile soil modified by acacia and spinifex plants in northwest Queensland, Australia Journal

Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed Central

View Source

Supporting Sources (26)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) The measurement of soil fungal:bacterial biomass ratios as an ..., accessed July 19, 2025,
(PDF) The measurement of soil fungal:bacterial biomass ratios as an ..., accessed July 19, 2025,
Contextual Support Journal

Soil microbial community composition under Eucalyptus plantations of different age in subtropical China - ResearchGate, accessed July 23, 2025

View Source
Preview of (PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025,
(PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025,
Contextual Support Journal

Caritat, P. de, & Cooper, M. (2011). The pH of Australian soils: Field results from a national survey. Soil Research, 49, 172-182.

View Source
Preview of ALLOCHTHONOUS CARBON LOADS AND POTENTIAL ... - La Trobe, accessed July 22, 2025,
ALLOCHTHONOUS CARBON LOADS AND POTENTIAL ... - La Trobe, accessed July 22, 2025,
Contextual Support Journal

Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands | Request PDF - ResearchGate

View Source
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
Contextual Support 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 28, 2025
Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 28, 2025
Contextual Support GreyLiterature

Fungal/bacterial ratios in grasslands with contrasting nitrogen management, accessed July 23, 2025

View Source
Preview of ausplotsR: TERN AusPlots Australian Ecosystem Monitoring Data - The Comprehensive R Archive Network, accessed July 15, 2025
ausplotsR: TERN AusPlots Australian Ecosystem Monitoring Data - The Comprehensive R Archive Network, accessed July 15, 2025
Contextual Support Journal

ASC - CHROMOSOLS - Soil Science Australia

View Source
Preview of ausplotsR: TERN AusPlots Australian Ecosystem Monitoring Data - The Comprehensive R Archive Network, accessed July 22, 2025
ausplotsR: TERN AusPlots Australian Ecosystem Monitoring Data - The Comprehensive R Archive Network, accessed July 22, 2025
Contextual Support Government

ausplotsR: TERN AusPlots Australian Ecosystem Monitoring Data - The Comprehensive R Archive Network

View Source
Preview of Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Contextual Support Journal

How should we manage our soils to increase soil carbon?, accessed May 10, 2026

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

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

View Source
Preview of Considering fungal: Bacterial dominance in soils - Methods, controls, and ecosystem implications | Request PDF - ResearchGate, accessed July 22, 2025
Considering fungal: Bacterial dominance in soils - Methods, controls, and ecosystem implications | Request PDF - ResearchGate, accessed July 22, 2025
Contextual Support Journal

Considering fungal: Bacterial dominance in soils - Methods, controls, and ecosystem implications | Request PDF - ResearchGate

View Source
Preview of Contrasting sensitivity of soil bacterial and fungal community composition to one year of water limitation in Scots pine mesocosms | FEMS Microbiology Ecology | Oxford Academic, accessed July 22, 2025
Contrasting sensitivity of soil bacterial and fungal community composition to one year of water limitation in Scots pine mesocosms | FEMS Microbiology Ecology | Oxford Academic, accessed July 22, 2025
Contextual Support Journal

Soil | Australia state of the environment 2021, accessed July 8, 2025

View Source
Preview of Ecosystem Processes – Environmental Data Collection Methods - TERN Australia
Ecosystem Processes – Environmental Data Collection Methods - TERN Australia
Methodology Source Government

Ecosystem Processes – Environmental Data Collection Methods - TERN Australia, accessed July 17, 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 Fungal/bacterial ratios in grasslands with contrasting nitrogen management, accessed July 19, 2025,
Fungal/bacterial ratios in grasslands with contrasting nitrogen management, accessed July 19, 2025,
Contextual Support Journal

Mechanisms and implications of bacterial–fungal competition for soil resources - PMC

View Source
Preview of Maintaining groundcover to reduce erosion and sustain production, accessed July 27, 2025,
Maintaining groundcover to reduce erosion and sustain production, accessed July 27, 2025,
Contextual Support Journal

Do regenerative grazing management practices improve vegetation and soil health in grazed rangelands? Preliminary insights from a space-for-time study in the Great Barrier Reef catchments, Australia - CSIRO Publishing, accessed July 23, 2025

View Source
Preview of Marine and Freshwater Research - CSIRO PUBLISHING, accessed July 22, 2025
Marine and Freshwater Research - CSIRO PUBLISHING, accessed July 22, 2025
Contextual Support Journal

Impact of inundation on soil microbiology - CSIRO Publishing

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 Mechanisms and implications of bacterial–fungal competition for soil resources | The ISME Journal | Oxford Academic, accessed July 18, 2025
Mechanisms and implications of bacterial–fungal competition for soil resources | The ISME Journal | Oxford Academic, accessed July 18, 2025
Contextual Support Journal

Mechanisms and implications of bacterial–fungal competition for soil resources | The ISME Journal | Oxford Academic

View Source
Preview of Microbial Communities in an Ephemeral Stream System and the Implications of Saline Mine Discharge - UQ eSpace - The University of Queensland, accessed July 22, 2025
Microbial Communities in an Ephemeral Stream System and the Implications of Saline Mine Discharge - UQ eSpace - The University of Queensland, accessed July 22, 2025
Contextual Support Journal

Climate dictates microbial community composition and diversity in Australian biological soil crusts (biocrusts) - PMC - PubMed Central

View Source
Preview of Microbial communities in floodplain ecosystems in relation to altered flow regimes and experimental flooding | Request PDF - ResearchGate, accessed July 22, 2025
Microbial communities in floodplain ecosystems in relation to altered flow regimes and experimental flooding | Request PDF - ResearchGate, accessed July 22, 2025
Contextual Support Journal

Microbial communities in floodplain ecosystems in relation to altered flow regimes and experimental flooding | Request PDF - ResearchGate

View Source
Preview of Soil condition | NSW State of the Environment, accessed July 22, 2025
Soil condition | NSW State of the Environment, accessed July 22, 2025
Contextual Support Journal

Soil condition | NSW State of the Environment

View Source
Preview of Soil microbes - farming with your underground livestock for healthy soil - Landscape SA, accessed July 22, 2025
Soil microbes - farming with your underground livestock for healthy soil - Landscape SA, accessed July 22, 2025
Contextual Support Government

Soil microbes - farming with your underground livestock for healthy soil - Landscape SA

View Source
Preview of The Biota of Intermittent Rivers and Ephemeral Streams: Prokaryotes, Fungi, and Protozoans | Request PDF - ResearchGate, accessed July 22, 2025
The Biota of Intermittent Rivers and Ephemeral Streams: Prokaryotes, Fungi, and Protozoans | Request PDF - ResearchGate, accessed July 22, 2025
Contextual Support

The Biota of Intermittent Rivers and Ephemeral Streams: Prokaryotes, Fungi, and Protozoans | Request PDF - ResearchGate

View Source
Preview of The fungal to bacterial ratio in soil food webs, and its measurement - ResearchGate, accessed July 22, 2025
The fungal to bacterial ratio in soil food webs, and its measurement - ResearchGate, accessed July 22, 2025
Methodology Source Journal

Mechanisms and implications of bacterial–fungal competition for soil resources - PMC

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

Context

  • Region Australia
  • Biome Arid Inland Floodplains & Ephemeral River Systems
  • Land Use Conservation / Protected Natural Areas
  • Assessment Conservation Target
  • Evidence Type DegradationThreshold

Lifecycle

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

Notes

This value is a practical management trigger indicating potential loss of fungal-mediated ecosystem services and ecosystem degradation.

Related Benchmarks

Other benchmarks in the AUS-AIF-CON-SFB family.

0.25 index Moderate
Conservation / Protected Natural Areas · Pristine Reference
Point Active v1