Fungal:Bacterial Ratio

AUS-AIF-LVG-SFB General Moderate confidence

Benchmark Value

0.3 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 OptimalRange Guard MinimumOnly Guard MaximumOnly Guard Point Guard MinimumOnly Guard OptimalRange Guard OptimalRange Guard Point Guard

Evidence & Context

Therefore, an F:B ratio below 0.3 can be considered a lower critical threshold for a pasture system in the target biome.

Metric Definition:

Fungal:Bacterial ratio below which the soil is considered degraded and bacterially dominated.

Benchmark Definition:

This benchmark defines the lower critical threshold of fungal to bacterial ratio below which soil is degraded and dominated by bacteria, indicating poor soil health in livestock grazing pastures.

Justification:

The literature consensus and studies indicate that F:B ratios below 0.3 signify degraded soil conditions.

Sources (1)

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 GreyLiterature

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

View Source

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

View Source
Preview of Grazing intensity influence soil microbial communities and their ..., accessed July 19, 2025
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

View Source
Preview of Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,
Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,
Contextual Support Government

Soil and Landscape Grid of Australia - CSIRO

View Source
Preview of Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - PMC - PubMed Central, accessed July 19, 2025
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
Preview of The fungal-bacterial ratio for soil health - Farmer's Weekly, accessed July 28, 2025
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
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
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

View Source
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 July 19, 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 July 19, 2025
Contextual Support 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, accessed July 19, 2025

View Source

Context

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

Lifecycle

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

Notes

Associated with impaired soil structure, low water infiltration, poor carbon retention, and a 'leaky' nutrient cycle prone to losses.

Related Benchmarks

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

— index Moderate
Livestock Grazing & Pasture · Conservation Target
OptimalRange Active v1
1.5 index Moderate
Livestock Grazing & Pasture · Conservation Target
MaximumOnly Active v1