Fungal:Bacterial Ratio

AUS-AMR-FOR-SFB General Low confidence

Benchmark Value

No specific value — see range
Range: 0.1 to 0.5 index
Optimal Range: 0.1 to 0.5
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 2 benchmarks together — the OptimalRange form drives the primary score, while 1 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary LowerThreshold Guard

Evidence & Context

Indicator Name: Fungal:Bacterial Ratio Reference Value: 0.1−0.5 Unit: Unitless

Metric Definition:

Fungal:Bacterial ratio, the ratio of fungal biomass to bacterial biomass in soil.

Benchmark Definition:

The ratio of fungal biomass to bacterial biomass in soil, indicating soil microbial community structure and function in Australian Arid Mountain Ranges & Uplands under Production Forestry.

Justification:

This benchmark is derived by inference due to the absence of direct field data, set above the natural Australian dryland baseline F:B ratio of ~0.05 to reflect the positive influence of best-practice management.

Sources (1)

Preview of Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths
Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths Journal

Derived Benchmark: Analysis of Fungal:Bacterial Ratios in Australian Arid Ecosystems and Analogous Land Management Systems

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Supporting Sources (9)

Additional references from the underlying research that informed this benchmark.

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 Bailey VL, Smith JL, Bolton H Jr.. Fungal-to-bacterial ratios in soils ..., accessed July 31, 2025,
Bailey VL, Smith JL, Bolton H Jr.. Fungal-to-bacterial ratios in soils ..., accessed July 31, 2025,
Contextual Support Journal

Bailey VL, Smith JL, Bolton H Jr.. Fungal-to-bacterial ratios in soils ..., accessed July 31, 2025,

View Source
Preview of Climate warming suppresses abundant soil fungal taxa and reduces soil carbon efflux in a semi‐arid grassland, accessed July 31, 2025,
Climate warming suppresses abundant soil fungal taxa and reduces soil carbon efflux in a semi‐arid grassland, accessed July 31, 2025,
Contextual Support Journal

Climate warming suppresses abundant soil fungal taxa and reduces soil carbon efflux in a semi‐arid grassland, accessed July 31, 2025,

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

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - Frontiers, accessed July 30, 2025,

View Source
Preview of Land | State of the Environment Report 2011
Land | State of the Environment Report 2011
Contextual Support Journal

Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 28, 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 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

The biogeography of relative abundance of soil fungi versus bacteria in surface topsoil, accessed August 1, 2025

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 to Bacterial Ratios: What and Why? - Ward Laboratories, Inc., accessed July 30, 2025,

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
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

View Source

Context

  • Region Australia
  • Biome Arid Mountain Ranges & Uplands
  • Land Use Production Forestry
  • Assessment Conservation Target
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 24 Mar 2026

Notes

Represents the best available condition for sustainably managed Production Forestry in Australian Arid Mountain Ranges & Uplands. No evidence supports an upper detrimental threshold; the natural environmental constraints impose a ceiling on the F:B ratio.

Related Benchmarks

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

0.05 index Low
Production Forestry · Conservation Target
LowerThreshold Active v1