Soil Phosphorus

AUS-TDG-AGR-SOP General Moderate confidence

Benchmark Value

No specific value — see range
Range: 6 to 12 mg/kg
Optimal Range: 6 to 12
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 12 benchmarks together — the OptimalRange form drives the primary score, while 11 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary LowerThreshold Guard UpperThreshold Guard Point Guard LowerThreshold Guard OptimalRange Guard UpperThreshold Guard OptimalRange Guard OptimalRange Guard MinimumOnly Guard MaximumOnly Guard OptimalRange Guard

Evidence & Context

Drawing from the rationale used for the benchmark value and considering the P requirements of native grasses, an Optimal Range of 6–12 mg/kg Olsen P (0-10 cm) is proposed.

Metric Definition:

Soil phosphorus concentration measured as Olsen P in the 0-10 cm soil depth.

Benchmark Definition:

Optimal ecological range for soil phosphorus balancing crop nutrition, soil biological activity, and minimizing environmental P loss.

Justification:

This range supports P sufficiency for sustainable crop production while minimizing environmental P load and supporting soil conditions aligned with native ecosystem P dynamics.

Sources (2)

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, Journal

Phosphorus nutrition of phosphorus-sensitive Australian native ..., accessed May 15, 2025,

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Preview of Why phosphorus is important - NSW Department of Primary Industries, accessed August 4, 2025
Why phosphorus is important - NSW Department of Primary Industries, accessed August 4, 2025 Government

(PDF) Individual plant species responses to phosphorus and ...

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Supporting Sources (5)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Phosphorus accumulation and other changes in soil ...
(PDF) Phosphorus accumulation and other changes in soil ...
Contextual Support Journal

Phosphorus Dynamics in the Soil–Plant–Environment Relationship in Cropping Systems: A Review - MDPI

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Preview of Phosphorus: a finite resource essential for life, critical for agriculture and food security
Phosphorus: a finite resource essential for life, critical for agriculture and food security
Contextual Support Journal

Phosphorus: a finite resource essential for life, critical for agriculture and food security

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Preview of Phosphorus: a finite resource essential for life, critical for agriculture and food security - CSIRO, accessed August 11, 2025
Phosphorus: a finite resource essential for life, critical for agriculture and food security - CSIRO, accessed August 11, 2025
Contextual Support Government

Nitrogen and Phosphorus Retranslocation of Leaves and Stemwood in a Mature Eucalyptus Forest Exposed to 5 Years of Elevated CO2 - Frontiers, accessed July 19, 2025,

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Preview of The phosphorus saturation degree as a universal agronomic and environmental soil P test
The phosphorus saturation degree as a universal agronomic and environmental soil P test
Contextual Support Journal

Soil | Australia state of the environment 2021

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Preview of www.agric.wa.gov.au
www.agric.wa.gov.au
Contextual Support

www.agric.wa.gov.au

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Context

  • Region Australia
  • Biome Temperate Dry Woodlands & Native Grasslands
  • Land Use Agricultural Crop Production
  • Assessment Pristine Reference
  • Evidence Type HealthyOperationalRange

Lifecycle

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

Notes

The range is lower and narrower than conventional agronomic optima, reflecting broader ecological objectives.

Related Benchmarks

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

8 mg/kg Moderate
Agricultural Crop Production · Pristine Reference
Point Active v1
5 mg/kg Moderate
Agricultural Crop Production · Pristine Reference
LowerThreshold Active v1
20 mg/kg Moderate
Agricultural Crop Production · Pristine Reference
UpperThreshold Active v1