Fungal:Bacterial Ratio

AUS-AIF-FOR-SFB General Moderate confidence

Benchmark Value

No specific value — see range

Range: 2 to 5 index

Thresholds: Lower: 1, Upper: —

Optimal Range: 2 to 5

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. The scoring engine uses 8 benchmarks together — the OptimalRange form drives the primary score, while 7 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

Therefore, a synthesized optimal functional range for a high-health, best-practice production forest in this specific biome is inferred to be 2.0 to 5.0.

Metric Definition:

The ratio of fungal to bacterial biomass (F:B ratio) in soil is a powerful integrative indicator, reflecting fundamental ecological strategies, the history of land management, and the overall functional state of a terrestrial ecosystem.

Benchmark Definition:

This benchmark defines the optimal fungal to bacterial biomass ratio range for sustainably managed production forests in Australia's Arid Inland Floodplains & Ephemeral River Systems, indicating a resilient and functionally diverse soil ecosystem.

Justification:

The value is derived by synthesizing data from mature Australian eucalypt forest analogues, semi-arid ecosystem studies, and large-scale international forest soil surveys, while critically adjusting for the known suppressive effect of aridity on fungal communities in Australia.

Sources (4)

Preview of Environmental management of riparian tree health in the Murray-Darling Basin, Australia - WIT Press, accessed July 21, 2025

Environmental management of riparian tree health in the Murray-Darling Basin, Australia - WIT Press, accessed July 21, 2025 Journal

Environmental management of riparian tree health in the Murray-Darling Basin, Australia - WIT Press

Preview of Fungal:bacterial ratio and soil microbial community structure in a national-scale monitoring network.

Fungal:bacterial ratio and soil microbial community structure in a national-scale monitoring network.

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, Journal

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

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, Journal

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

Supporting Sources (21)

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

Contextual Support GreyLiterature

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

Preview of Aridity differentially alters the stability of soil bacterial and fungal networks in coastal and inland areas of Australia - PubMed

Aridity differentially alters the stability of soil bacterial and fungal networks in coastal and inland areas of Australia - PubMed

Contextual Support Direct Evidence GreyLiterature

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

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

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 Direct Evidence Journal

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

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

Preview of Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed, accessed July 28, 2025,

Biogeographical patterns of the soil fungal:bacterial ratio across France - PubMed, accessed July 28, 2025,

Direct Evidence Journal

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

Preview of Changes in Soil Microbial Community Structure Influenced by Agricultural Management Practices in a Mediterranean Agro-Ecosystem | PLOS One - Research journals, accessed August 5, 2025,

Changes in Soil Microbial Community Structure Influenced by Agricultural Management Practices in a Mediterranean Agro-Ecosystem | PLOS One - Research journals, accessed August 5, 2025,

Contextual Support Journal

Changes in Soil Microbial Community Structure Influenced by Agricultural Management Practices in a Mediterranean Agro-Ecosystem | PLOS One - Research journals

Preview of Forest succession improves the complexity of soil microbial interaction and ecological stochasticity of community assembly: Evidence from Phoebe bournei-dominated forests in subtropical regions

Forest succession improves the complexity of soil microbial interaction and ecological stochasticity of community assembly: Evidence from Phoebe bournei-dominated forests in subtropical regions

Contextual Support Journal

Forest succession improves the complexity of soil microbial interaction and ecological stochasticity of community assembly: Evidence from Phoebe bournei-dominated forests in subtropical regions

Preview of Forest succession improves the complexity of soil microbial interaction and ecological stochasticity of community assembly: Evidence from Phoebe bournei-dominated forests in subtropical regions, accessed July 20, 2025,

Forest succession improves the complexity of soil microbial interaction and ecological stochasticity of community assembly: Evidence from Phoebe bournei-dominated forests in subtropical regions, accessed July 20, 2025,

Contextual Support Journal

Forest succession improves the complexity of soil microbial interaction and ecological stochasticity of community assembly: Evidence from Phoebe bournei-dominated forests in subtropical regions - Frontiers

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

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

Preview of Metal Toxicity Affects Fungal and Bacterial Activities in Soil Differently - PMC, accessed July 20, 2025,

Metal Toxicity Affects Fungal and Bacterial Activities in Soil Differently - PMC, accessed July 20, 2025,

Contextual Support Journal

Metal Toxicity Affects Fungal and Bacterial Activities in Soil Differently - PMC

Preview of Microbial community composition and activity in paired irrigated and non-irrigated pastures in New Zealand - CSIRO Publishing, accessed August 3, 2025

Microbial community composition and activity in paired irrigated and non-irrigated pastures in New Zealand - CSIRO Publishing, accessed August 3, 2025

Contextual Support Journal

Microbial community composition and activity in paired irrigated and non-irrigated pastures in New Zealand - CSIRO Publishing, accessed July 29, 2025

Preview of RIvER RED guMs AND wooDLAND FoREsts - Natural Resources Commission, accessed July 20, 2025,

RIvER RED guMs AND wooDLAND FoREsts - Natural Resources Commission, accessed July 20, 2025,

Contextual Support Journal

RIvER RED guMs AND wooDLAND FoREsts - Natural Resources Commission

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

Preview of Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - Frontiers, accessed July 20, 2025,

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - Frontiers, accessed July 20, 2025,

Contextual Support GreyLiterature

Revisiting the hypothesis that fungal-to-bacterial dominance characterises turnover of soil organic matter and nutrients | Request PDF - ResearchGate

Preview of Soil Microbial Community Successional Patterns during Forest Ecosystem Restoration | Applied and Environmental Microbiology - ASM Journals, accessed July 20, 2025,

Soil Microbial Community Successional Patterns during Forest Ecosystem Restoration | Applied and Environmental Microbiology - ASM Journals, accessed July 20, 2025,

Contextual Support Direct Evidence Journal

Soil Bacterial and Fungal Communities Show Distinct Recovery Patterns during Forest Ecosystem Restoration | Applied and Environmental Microbiology - ASM Journals

Preview of Soil respiration–driven CO2 pulses dominate Australia's flux variability

Soil respiration–driven CO2 pulses dominate Australia's flux variability

Contextual Support Journal

The incorporation of fungal to bacterial ratios and plant ecosystem ...

Preview of The fungal-bacterial ratio for soil health - Farmer's Weekly, accessed July 12, 2025,

The fungal-bacterial ratio for soil health - Farmer's Weekly, accessed July 12, 2025,

Direct Evidence Journal

The fungal-bacterial ratio for soil health - Farmer's Weekly

Preview of The incorporation of fungal to bacterial ratios and plant ecosystem effect traits into a state-and-transition model of land-use change in semi-arid grasslands - Research @ Flinders, accessed August 3, 2025

The incorporation of fungal to bacterial ratios and plant ecosystem effect traits into a state-and-transition model of land-use change in semi-arid grasslands - Research @ Flinders, accessed August 3, 2025

Contextual Support Direct Evidence Journal

The incorporation of fungal to bacterial ratios and plant ecosystem effect traits into a state-and-transition model of land-use change in semi-arid grasslands - Research @ Flinders

Preview of Typology of arid-zone floodplain wetlands of the Paroo River (inland Australia) and the influence of water regime, turbidity, and salinity on their aquatic invertebrate assemblages - ResearchGate, accessed July 20, 2025,

Typology of arid-zone floodplain wetlands of the Paroo River (inland Australia) and the influence of water regime, turbidity, and salinity on their aquatic invertebrate assemblages - ResearchGate, accessed July 20, 2025,

Contextual Support GreyLiterature

Typology of arid-zone floodplain wetlands of the Paroo River (inland Australia) and the influence of water regime, turbidity, and salinity on their aquatic invertebrate assemblages - ResearchGate

Context

Region Australia
Biome Arid Inland Floodplains & Ephemeral River Systems
Land Use Production Forestry
Assessment Conservation Target
Vegetation Forest
Evidence Type TargetCondition

Lifecycle

Status Active
Version 1
Effective From 26 May 2026

Notes

Lower Critical Threshold: 1 index. No upper detrimental threshold — higher values are always better up to natural saturation. The range represents a soil ecosystem that is resilient, functionally diverse, and managed in a way that successfully emulates the key microbial characteristics of a mature native forest under arid conditions.

Related Benchmarks

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