Fungal:Bacterial Ratio

AUS-TSR-CON-SFB General High confidence

Benchmark Value

0.6 index

Range: 0.6 to 0.6 index

Optimal Range: 0.6 to 0.6

Direction: Higher is desirable ↑

Form: Point

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 Point Guard MinimumOnly Guard LowerThreshold Guard OptimalRange Guard Point Guard LowerThreshold Guard Point Guard

Evidence & Context

Using PLFA analysis, the study determined the F:B ratio in these protected rainforest soils. While the exact numerical value is not stated in the text, analysis of the published bar chart (Figure 3 in the paper) indicates a PLFA-based F:B ratio of approximately 0.6.

Metric Definition:

Ratio of Fungal PLFA to Bacterial PLFA in soil microbial communities

Benchmark Definition:

This benchmark represents the fungal to bacterial PLFA ratio in undisturbed tropical rainforest soils, indicating a balanced microbial community that supports high soil carbon and microbial biomass.

Justification:

This value is derived from undisturbed rainforest sites in North Queensland, representing the best available condition for this biome. It signifies a fungal-balanced system with high microbial biomass and soil carbon relative to disturbed land uses.

Sources (2)

Preview of (PDF) Relative to rainforests and grasslands, banana and ..., accessed July 23, 2025

(PDF) Relative to rainforests and grasslands, banana and ..., accessed July 23, 2025 Journal

(PDF) Relative to rainforests and grasslands, banana and ..., accessed July 23, 2025

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 Journal

Soil Fungal:Bacterial Ratios Are Linked to Altered Carbon Cycling - Frontiers, accessed July 23, 2025

Supporting Sources (20)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Managing a World Heritage Site in the Face of Climate Change: A Case Study of the Wet Tropics in Northern Queensland - ResearchGate, accessed July 23, 2025

(PDF) Managing a World Heritage Site in the Face of Climate Change: A Case Study of the Wet Tropics in Northern Queensland - ResearchGate, accessed July 23, 2025

Contextual Support Journal

(PDF) Managing a World Heritage Site in the Face of Climate Change: A Case Study of the Wet Tropics in Northern Queensland - ResearchGate, accessed July 23, 2025

Preview of (PDF) The measurement of soil fungal:bacterial biomass ratios as an ..., accessed July 19, 2025,

(PDF) The measurement of soil fungal:bacterial biomass ratios as an ..., accessed July 19, 2025,

Contextual Support Journal

Soil microbial community composition under Eucalyptus plantations of different age in subtropical China - ResearchGate, accessed July 23, 2025

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 June 7, 2025,

Preview of Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 23, 2025

Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 23, 2025

Contextual Support GreyLiterature

Succession and Soil Productivity - GroundGrocer, accessed July 23, 2025

Preview of Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 28, 2025

Are Fungal to Bacterial Ratios (F:B Ratio) Important for Plant Growth? - Garden Myths, accessed July 28, 2025

Contextual Support GreyLiterature

Fungal/bacterial ratios in grasslands with contrasting nitrogen management, accessed July 23, 2025

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

Root Structure and Functioning for Efficient Acquisition of Phosphorus: Matching Morphological and Physiological Traits

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 Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization | Applied and Environmental Microbiology - ASM Journals, accessed July 28, 2025

Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization | Applied and Environmental Microbiology - ASM Journals, accessed July 28, 2025

Contextual Support

Contrasting Soil pH Effects on Fungal and Bacterial Growth Suggest Functional Redundancy in Carbon Mineralization | Applied and Environmental Microbiology - ASM Journals, accessed July 23, 2025

Preview of Converting tropical rainforest to native rubber plantations alters soil bacterial and fungal communities - Maximum Academic Press, accessed July 23, 2025

Converting tropical rainforest to native rubber plantations alters soil bacterial and fungal communities - Maximum Academic Press, accessed July 23, 2025

Contextual Support Journal

Converting tropical rainforest to native rubber plantations alters soil bacterial and fungal communities - Maximum Academic Press, accessed July 23, 2025

Preview of Criteria and Indicators for Sustainable Forest Management in Victoria, accessed July 19, 2025

Criteria and Indicators for Sustainable Forest Management in Victoria, accessed July 19, 2025

Contextual Support Journal

Soil health: the foundation of sustainable agriculture - 2001 ...

Preview of Ecology of streams in a biogeographic isolate—the Queensland Wet Tropics, Australia - ResearchOnline@JCU, accessed July 23, 2025

Ecology of streams in a biogeographic isolate—the Queensland Wet Tropics, Australia - ResearchOnline@JCU, accessed July 23, 2025

Contextual Support Journal

Ecology of streams in a biogeographic isolate—the Queensland Wet Tropics, Australia - ResearchOnline@JCU, accessed July 23, 2025

Preview of Impact of drought on soil microbial biomass and extracellular enzyme activity - Frontiers, accessed July 23, 2025

Impact of drought on soil microbial biomass and extracellular enzyme activity - Frontiers, accessed July 23, 2025

Contextual Support Journal

Relative to rainforests and grasslands, banana and sugarcane soils ..., accessed July 23, 2025

Preview of Looking for suitable indicators. What should be considered to assess the effects of use and management on soil health? - ResearchGate, accessed July 19, 2025,

Looking for suitable indicators. What should be considered to assess the effects of use and management on soil health? - ResearchGate, accessed July 19, 2025,

Contextual Support Journal

(PDF) The measurement of soil fungal:bacterial biomass ratios as an indicator of ecosystem self-regulation in temperate meadow grasslands - ResearchGate, accessed July 23, 2025

Preview of Managing a World Heritage Site in the Face of Climate Change: A Case Study of the Wet Tropics in Northern Queensland - MDPI

Managing a World Heritage Site in the Face of Climate Change: A Case Study of the Wet Tropics in Northern Queensland - MDPI

Contextual Support Journal

Managing a World Heritage Site in the Face of Climate Change: A Case Study of the Wet Tropics in Northern Queensland - MDPI, accessed July 23, 2025

Preview of Modified fungal diversity in dense clay subsoils after deep-banding organic substrate - CSIRO Publishing, accessed July 23, 2025

Modified fungal diversity in dense clay subsoils after deep-banding organic substrate - CSIRO Publishing, accessed July 23, 2025

Contextual Support Journal

Modified fungal diversity in dense clay subsoils after deep-banding organic substrate - CSIRO Publishing, accessed July 23, 2025

Preview of Soil | Australia state of the environment 2021, accessed August 3, 2025,

Soil | Australia state of the environment 2021, accessed August 3, 2025,

Contextual Support

The effects of clipping frequency and nitrogen fertilisation on greenhouse gas emissions and net ecosystem exchange in an Australian temperate grassland - CSIRO PUBLISHING | The Rangeland Journal

Preview of Things you need to know about the Fungal to Bacterial Ratio (F:B) - MicroBiometer, accessed July 28, 2025

Things you need to know about the Fungal to Bacterial Ratio (F:B) - MicroBiometer, accessed July 28, 2025

Contextual Support GreyLiterature

Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed July 23, 2025

Preview of Tropical Rainforest Restoration Plantations Are Slow to Restore the Soil Biological and Organic Carbon Characteristics of Old Growth Rainforest - PMC, accessed July 23, 2025

Tropical Rainforest Restoration Plantations Are Slow to Restore the Soil Biological and Organic Carbon Characteristics of Old Growth Rainforest - PMC, accessed July 23, 2025

Contextual Support

Tropical Rainforest Restoration Plantations Are Slow to Restore the Soil Biological and Organic Carbon Characteristics of Old Growth Rainforest - PMC, accessed July 23, 2025

Preview of Unravelling the effects of tropical land use conversion on the soil microbiome, accessed July 23, 2025

Unravelling the effects of tropical land use conversion on the soil microbiome, accessed July 23, 2025

Contextual Support Journal

Unravelling the effects of tropical land use conversion on the soil microbiome, accessed July 23, 2025

Preview of Wet Tropics of Queensland - UNESCO World Heritage Centre, accessed July 22, 2025,

Wet Tropics of Queensland - UNESCO World Heritage Centre, accessed July 22, 2025,

Contextual Support GreyLiterature

Wet Tropics of Queensland - UNESCO World Heritage Centre, accessed July 23, 2025

Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Conservation / Protected Natural Areas
Assessment Pristine Reference
Vegetation Forest
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 24 Mar 2026

Notes

No upper detrimental threshold — higher values are always better up to natural saturation. Lower Critical Threshold: Ratios below ~0.4 indicate a shift to a degraded, bacterially-dominated state with compromised carbon storage and nutrient retention. Exceptionally high ratios may indicate environmental stressors such as extreme acidity.

Related Benchmarks

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