Fungal:Bacterial Ratio

AUS-TSW-CON-SFB General Moderate confidence

Benchmark Value

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.

Evidence & Context

A PLFA-based F:B ratio of >3.0 is proposed as the benchmark representing a high-health state for conservation areas in Australia's Temperate Semi-Arid Shrublands & Open Woodlands.

Metric Definition:

Fungal to bacterial biomass ratio in soil as measured by Phospholipid Fatty Acid (PLFA) analysis.

Benchmark Definition:

This benchmark represents the minimum fungal to bacterial biomass ratio in soil indicating a high-health state for conservation areas in Australia's Temperate Semi-Arid Shrublands & Open Woodlands.

Justification:

Derived by triangulating qualitative evidence from the primary source (Wong et al. 2015) with quantitative data from analogous well-managed Australian pastures (F:B of 2.3-3.5+ via PLFA).

Sources (2)

ausveg - fact sheet: soil microbiology, accessed July 18, 2025 Journal

ausveg - fact sheet: soil microbiology

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 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 Temperate Semi-Arid Shrublands & Open Woodlands
Land Use Conservation / Protected Natural Areas
Assessment Conservation Target
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 8 Jun 2026

Notes

No upper detrimental threshold — higher values are always better up to natural saturation. The benchmark represents a high-health conservation state. The value is derived by extrapolation and is method-dependent. The optimal range is a successional trajectory rather than a fixed range.

Related Benchmarks

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