Fungal:Bacterial Ratio

AUS-AIF-LVG-SFB General Moderate confidence

Benchmark Value

No specific value — see range

Range: 0.8 to 1.2 index

Optimal Range: 0.8 to 1.2

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

Contributing Benchmarks

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

Evidence & Context

The derived benchmark, representing the best available condition, is presented below, along with a summary of its functional range.

Metric Definition:

Ratio of fungal to bacterial biomass in soil, indicating the balance between fungal and bacterial microbial communities.

Benchmark Definition:

This benchmark represents the optimal fungal to bacterial ratio in soil for a resilient and productive pasture in arid inland floodplains under livestock grazing, indicating a balanced soil microbial community.

Justification:

The benchmark is derived by synthesizing findings from the most relevant study in Australian semi-arid grasslands (Wong et al., 2015), which showed higher F:B ratios in native pastures, with general pasture values from other literature.

Sources (1)

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 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

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Supporting Sources (8)

Additional references from the underlying research that informed this benchmark.

Preview of 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 August 5, 2025,

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 August 5, 2025,

Contextual Support Journal

Ludwig, J.A., Bastin, G.N., Chewings, V.H., Eager, R.W., and Liedloff, A.C. (2005). Clearing savannas for use as rangelands in Queensland: Altered landscapes and water-erosion processes. Rangeland Journal, 27(2), 135-149.

View Source

Fungal/bacterial ratios in grassland with contrasting nitrogen management - Wageningen University & Research, accessed July 28, 2025

Contextual Support Journal

Fungal to Bacterial Ratios: What and Why? - Ward Laboratories, Inc.

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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

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Grazing intensity influence soil microbial communities and their ..., accessed July 19, 2025

Contextual Support Journal

Grazing intensity influence soil microbial communities and their ..., accessed July 19, 2025

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Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,

Contextual Support Government

Soil and Landscape Grid of Australia - CSIRO

View Source

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - PMC - PubMed Central, accessed July 19, 2025

Contextual Support Journal

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - PMC - PubMed Central

View Source

The fungal-bacterial ratio for soil health - Farmer's Weekly, accessed July 28, 2025

Contextual Support GreyLiterature

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

View Source

Contextual Support Journal

View Source

Context

Region Australia
Biome Arid Inland Floodplains & Ephemeral River Systems
Land Use Livestock Grazing & Pasture
Assessment Conservation Target
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 8 Jun 2026

Notes

Lower Critical Threshold: 0.3. Upper Detrimental Threshold: 1.5. A ratio approaching or exceeding 1.0 indicates a shift to a balanced or fungal-leaning system, characteristic of regenerative management. Higher values above 1.5 indicate a shift toward woody vegetation, undesirable for pasture productivity.

Related Benchmarks

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