Soil Phosphorus

AUS-AMR-CON-SOP General High confidence

Benchmark Value

No specific value — see range
Range: 5 to 15 mg/kg
Optimal Range: 5 to 15
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 5 benchmarks together — the OptimalRange form drives the primary score, while 4 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MaximumOnly Guard MinimumOnly Guard OptimalRange Guard OptimalRange Guard

Evidence & Context

The reference value represents the median available P (Colwell P) for the 0-10cm soil layer, derived from the TERN Soil and Landscape Grid across all protected conservation areas (CAPAD) within the Arid Mountain Ranges & Uplands biome (defined by IBRA regions MAC, FLB, BHC, CER, PIL).

Metric Definition:

Available phosphorus (Colwell P) concentration in the 0-10 cm soil layer

Benchmark Definition:

This benchmark represents the natural range of available phosphorus in the top 10 cm of soil in conservation areas of the Arid Mountain Ranges & Uplands biome, reflecting a healthy, low-phosphorus state that supports native plant communities.

Justification:

Derived from a large-scale spatial analysis of the TERN Soil and Landscape Grid dataset, calibrated with data from undisturbed, non-fertilised, non-cropped sites, reflecting natural phosphorus scarcity in Australian arid ecosystems.

Sources (5)

Preview of Indicative Soil Phosphorus Report | LongPaddock | Queensland Government
Indicative Soil Phosphorus Report | LongPaddock | Queensland Government Government

Indicative Soil Phosphorus Report | LongPaddock | Queensland Government

View Source
Preview of Phosphorus Nutrition of Proteaceae in Severely Phosphorus-Impoverished Soils: Are There Lessons To Be Learned for Future Crops? - PubMed Central, accessed August 4, 2025
Phosphorus Nutrition of Proteaceae in Severely Phosphorus-Impoverished Soils: Are There Lessons To Be Learned for Future Crops? - PubMed Central, accessed August 4, 2025 Journal

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

View Source
Preview of Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - Release 1
Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - Release 1

Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - TERN Data Discovery Portal

View Source
Preview of Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA, accessed May 13, 2025,
Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA, accessed May 13, 2025, Government

Understanding soil tests for pastures | Soil | Farm management ..., accessed July 17, 2025

View Source
Preview of The incidence of low phosphorus soils in Australia | Request PDF - ResearchGate, accessed July 21, 2025,
The incidence of low phosphorus soils in Australia | Request PDF - ResearchGate, accessed July 21, 2025, Journal

Survival of native plants of Hawkesbury Sandstone communities with additional nutrients: effect of plant age and habitat - ResearchGate

View Source

Supporting Sources (17)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Mineral Nutrition of Plants in Australia's Arid Zone - ResearchGate, accessed July 13, 2025
(PDF) Mineral Nutrition of Plants in Australia's Arid Zone - ResearchGate, accessed July 13, 2025
Contextual Support

Putting the P in Ptilotus: a phosphorus-accumulating herb native to Australia - PMC

View Source
Preview of (PDF) Soil phosphorus tests II: A comparison of soil test–crop response relationships for different soil tests and wheat - ResearchGate, accessed July 7, 2025,
(PDF) Soil phosphorus tests II: A comparison of soil test–crop response relationships for different soil tests and wheat - ResearchGate, accessed July 7, 2025,
Methodology Source Journal

(PDF) Soil phosphorus tests II: A comparison of soil test–crop response relationships for different soil tests and wheat - ResearchGate

View Source
Preview of Australia - Soils, Climate, Erosion | Britannica
Australia - Soils, Climate, Erosion | Britannica
Contextual Support GreyLiterature

SOIL TESTING

View Source
Preview of Australia's bioregions (IBRA) - DCCEEW, accessed July 15, 2025
Australia's bioregions (IBRA) - DCCEEW, accessed July 15, 2025
Contextual Support

Interim Biogeographic Regionalisation for Australia (IBRA), Version 7 (Regions)

View Source
Preview of Australian dryland soils are acidic and nutrient-depleted, and have ..., accessed August 1, 2025
Australian dryland soils are acidic and nutrient-depleted, and have ..., accessed August 1, 2025
Contextual Support

Australian dryland soils are acidic and nutrient-depleted, and have ...

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

View Source
Preview of Interim Biogeographic Regionalisation for Australia - Wikipedia, accessed July 13, 2025,
Interim Biogeographic Regionalisation for Australia - Wikipedia, accessed July 13, 2025,
Contextual Support GreyLiterature

Category:IBRA regions - Wikipedia

View Source
Preview of Interim Biogeographic Regionalisation for Australia (IBRA7) Codes - DCCEEW, accessed August 1, 2025
Interim Biogeographic Regionalisation for Australia (IBRA7) Codes - DCCEEW, accessed August 1, 2025
Contextual Support Government

Cobar Peneplain bioregion - DCCEEW

View Source
Preview of Phosphate minerals from Reaphook Hill, Flinders Ranges, South Australia | Mineralogical Magazine | Cambridge Core, accessed August 1, 2025
Phosphate minerals from Reaphook Hill, Flinders Ranges, South Australia | Mineralogical Magazine | Cambridge Core, accessed August 1, 2025
Contextual Support

Phosphate minerals from Reaphook Hill, Flinders Ranges, South Australia | Mineralogical Magazine | Cambridge Core

View Source
Preview of Phosphorus - Qld | Fact Sheets | soilquality.org.au, accessed August 28, 2025
Phosphorus - Qld | Fact Sheets | soilquality.org.au, accessed August 28, 2025
Contextual Support Government

Phosphorus - WA | Fact Sheets | soilquality.org.au

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

View Source
Preview of Phosphorus requirements of Australian native plants - ResearchGate, accessed August 4, 2025
Phosphorus requirements of Australian native plants - ResearchGate, accessed August 4, 2025
Contextual Support Journal

Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed July 22, 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
Direct Evidence Government

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

View Source
Preview of Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - TERN Data Discovery Portal, accessed August 1, 2025
Soil and Landscape Grid National Soil Attribute Maps - Available Phosphorus (3" resolution) - TERN Data Discovery Portal, accessed August 1, 2025
Contextual Support Government

Soil and Landscape Grid National Soil Attribute Maps - Total Phosphorus (3" resolution) - Release 2 - TERN Data Discovery Portal

View Source
Preview of Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,
Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,
Contextual Support Government

Soil and Landscape Grid of Australia - CSIRO

View Source
Preview of THE PHOSPHATE CONTENT OF AUSTRALIAN SOILS - CSIRO Publishing, accessed August 1, 2025
THE PHOSPHATE CONTENT OF AUSTRALIAN SOILS - CSIRO Publishing, accessed August 1, 2025
Contextual Support Journal

THE PHOSPHATE CONTENT OF AUSTRALIAN SOILS - CSIRO Publishing

View Source
Preview of Too much of a good thing: phosphorus over-fertilisation in rehabilitated landscapes of high biodiversity value - Australian Centre for Geomechanics, accessed August 1, 2025
Too much of a good thing: phosphorus over-fertilisation in rehabilitated landscapes of high biodiversity value - Australian Centre for Geomechanics, accessed August 1, 2025
Contextual Support GreyLiterature

Fertilisers for native plants in gardens - Australian Plants Society | SA Region Inc, accessed July 22, 2025

View Source

Context

  • Region Australia
  • Biome Arid Mountain Ranges & Uplands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 10 Jun 2026

Notes

Lower Critical Threshold: 3 mg/kg. Upper Detrimental Threshold: 20 mg/kg. The benchmark reflects the ecologically healthy, low phosphorus state characteristic of Australian arid mountain ranges and uplands conservation areas.