Soil Phosphorus

AUS-ASC-AGR-SOP General Moderate confidence

Benchmark Value

No specific value — see range

Range: 15 to 30 mg/kg

Optimal Range: 15 to 30

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.

Evidence & Context

For Available Phosphorus (Colwell P), an indicative range might be 15-30 mg/kg for soils with low to moderate PBI.

Metric Definition:

Available Phosphorus (e.g., Colwell P): This is more directly related to immediate plant uptake and is a common metric for agronomic management.

Justification:

The reference value for available P would seek to keep it within a range that supports selected crops adequately but avoids levels that pose an environmental risk or indicate nutrient imbalance.

Sources (1)

openresearch-repository.anu.edu.au, accessed on May 31, 2025 Journal

openresearch-repository.anu.edu.au, accessed on May 31, 2025

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Supporting Sources (14)

Additional references from the underlying research that informed this benchmark.

A simple phosphorus buffering index for Australian soils - University of Tasmania Open Access Repository Cover sheet

Contextual Support GreyLiterature

Cycling of phosphorus in grazing systems - NSW Department of Primary Industries

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Australian Alps Montane Grasslands | One Earth, accessed on May 28, 2025

Contextual Support GreyLiterature

Alpine Rural Directions Strategy Issues and Opportunities Paper - AWS, accessed on May 31, 2025

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Foreword: New directions for phosphorus management in Australian soils and farming systems - ResearchGate, accessed on May 31, 2025

Contextual Support GreyLiterature

Foreword: New directions for phosphorus management in Australian soils and farming systems - ResearchGate, accessed on May 31, 2025

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Global patterns and drivers of soil total phosphorus concentration - ESSD Copernicus, accessed on May 31, 2025

Contextual Support Journal

Global patterns and drivers of soil total phosphorus concentration - ESSD Copernicus, accessed August 1, 2025

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Preview of Integrating legacy soil phosphorus into sustainable nutrient management strategies for future food, bioenergy and water security, accessed on May 31, 2025

Integrating legacy soil phosphorus into sustainable nutrient management strategies for future food, bioenergy and water security, accessed on May 31, 2025

Contextual Support Journal

Integrating legacy soil phosphorus into sustainable nutrient management strategies for future food, bioenergy and water security, accessed on May 31, 2025

View Source

Phosphorus for high rainfall clover pastures in Western Australia | Agriculture and Food

Contextual Support

Agronomic soil tests can be used to estimate dissolved reactive phosphorus loss, accessed on May 31, 2025

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Preview of Recovery of Alpine Vegetation from Grazing and Drought: Data from Long-term Photoquadrats in Kosciuszko National Park, Australia - BioOne Complete, accessed on May 31, 2025

Recovery of Alpine Vegetation from Grazing and Drought: Data from Long-term Photoquadrats in Kosciuszko National Park, Australia - BioOne Complete, accessed on May 31, 2025

Contextual Support Journal

Sustainably growing horticulture value in cool climate Australia - University of Tasmania, accessed on May 31, 2025

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Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed August 4, 2025

Contextual Support Journal

NCC: Regenerative Agriculture and Soil Health - Wet Tropics Plan, accessed July 27, 2025,

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Regenerative agriculture in Australia: the changing face of farming - Frontiers, accessed on May 31, 2025

Contextual Support Journal

Residue Addition Can Mitigate Soil Health Challenges with Climate Change in Drylands: Insights from a Field Warming Experiment in Semi-Arid Texas - MDPI, accessed on May 31, 2025

View Source

Preview of Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - Release 1 - CSIRO Data Access Portal, accessed on May 31, 2025

Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - Release 1 - CSIRO Data Access Portal, accessed on May 31, 2025

Methodology Source Government

Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - Release 1 - CSIRO Data Access Portal, accessed August 1, 2025

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Soil and Landscape Grid of Australia - TERN - esoil.io, accessed on May 31, 2025

Contextual Support Journal

Soil and Landscape Grid of Australia - TERN - esoil.io, accessed on May 31, 2025

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SUMMIT TECHNOTES TN03, accessed on May 31, 2025

Contextual Support Journal

Phosphorus - Soil Quality Knowledge Base, accessed on May 31, 2025

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theaustralianalpsnationalparks.org, accessed on May 25, 2025,

Contextual Support Journal

theaustralianalpsnationalparks.org

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www.environment.nsw.gov.au, accessed on May 25, 2025,

Contextual Support

Australian Alps Montane Grasslands | One Earth, accessed on May 31, 2025

View Source

Context

Region Australia
Biome Alpine and Subalpine Complex
Land Use Agricultural Crop Production
Assessment Pristine Reference
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. The reference Colwell P range should ideally be presented as conditional upon PBI categories.

Related Benchmarks

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