Soil Phosphorus

AUS-TDG-FOR-SOP General Moderate confidence

Benchmark Value

No specific value — see range

Range: 3 to 8 mg/kg

Optimal Range: 3 to 8

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 14 benchmarks together — the OptimalRange form drives the primary score, while 13 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

This range (3-8 mg/kg available P, using Colwell P or Olsen P methods which are common for Australian soils) represents the best available condition for production forestry in Australian Temperate Dry Woodlands & Native Grasslands that prioritizes high environmental health, ecological functions, and biodiversity.

Metric Definition:

Available soil phosphorus measured by Colwell P or Olsen P methods representing best available condition for production forestry.

Benchmark Definition:

This benchmark defines the range of available soil phosphorus that represents the best ecological condition for production forestry in Australian temperate dry woodlands and native grasslands, supporting environmental health, ecological functions, and biodiversity.

Justification:

Represents a low P status reflecting natural conditions to which native flora is adapted, supporting biodiversity and ecosystem function under sustainable forestry. Avoids P enrichment detrimental to P-sensitive native species.

Sources (1)

Preview of Al-Beidh, S., & Al-Tawaha, A. R. M. (2023). Basic Properties and Mineralogy of Soils and Their Impact on the Growth of Jarrah Forest in Southwestern Australia. Land, 12(6), 1236.

Al-Beidh, S., & Al-Tawaha, A. R. M. (2023). Basic Properties and Mineralogy of Soils and Their Impact on the Growth of Jarrah Forest in Southwestern Australia. Land, 12(6), 1236. Journal

Soil Characteristics and Fertility of the Unique Jarrah Forest of Southwestern Australia, with Particular Consideration of Plant Nutrition and Land Rehabilitation - MDPI

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Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Preview of Phosphorus fertiliser management for pastures based on native grasses in south-eastern Australia - CSIRO Publishing, accessed August 5, 2025,

Phosphorus fertiliser management for pastures based on native grasses in south-eastern Australia - CSIRO Publishing, accessed August 5, 2025,

Contextual Support GreyLiterature

Phosphorus nutrition of phosphorus-sensitive Australian native ...

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Phosphorus nutrition of phosphorus-sensitive Australian native plants: threats to plant communities in a global biodiversity hotspot - PMC

Contextual Support Journal

(PDF) Sensitivity of seedling growth to phosphorus supply in six tree ...

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Preview of Sensitivity of seedling growth to phosphorus supply in six tree species of the Australian Great Western Woodlands - ResearchGate, accessed August 11, 2025

Sensitivity of seedling growth to phosphorus supply in six tree species of the Australian Great Western Woodlands - ResearchGate, accessed August 11, 2025

Contextual Support Journal

Understanding soil tests for pastures | Soil | Farm management ...

View Source

Context

Region Australia
Biome Temperate Dry Woodlands & Native Grasslands
Land Use Production Forestry
Assessment Not Stated
Evidence Type ReferenceCondition

Lifecycle

Status Superseded
Version 2
Effective From 10 Jun 2026
Effective To 10 Jun 2026

Notes

Reflects the naturally P-impoverished status of these ancient, weathered Australian soils to which the native flora is highly adapted. The benchmark aims to maintain conditions that support characteristic native plant communities and avoid P enrichment, which is known to be detrimental to many P-sensitive native species and overall ecosystem integrity. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TDG-FOR-SOP family.