Soil Phosphorus

AUS-AKW-CON-SOP General Moderate confidence

Benchmark Value

No specific value — see range
Range: 2 to 15 mg/kg
Optimal Range: 2 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 11 benchmarks together — the OptimalRange form drives the primary score, while 10 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

the proposed optimal range for available phosphorus (Colwell-P) in this biome is 2 - 15 mg/kg

Metric Definition:

Optimal range of available phosphorus (Colwell-P) for maintaining native ecosystem integrity.

Benchmark Definition:

This benchmark defines the safe operating range of available phosphorus in the Arid Karstic Woodlands & Shrublands biome where native plants thrive and ecosystem integrity is maintained.

Justification:

Represents a balance between nutrient availability and risk of competitive exclusion by P-responsive species.

Sources (1)

Preview of An inventory and condition survey of the Western Australian part of the Nullarbor region, accessed July 25, 2025
An inventory and condition survey of the Western Australian part of the Nullarbor region, accessed July 25, 2025 Journal

(PDF) Phosphorus status and saturation in soils that drain into the ...

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Context

  • Region Australia
  • Biome Arid Karstic Woodlands & Shrublands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Conservation Target
  • Evidence Type HealthyOperationalRange

Lifecycle

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

Notes

Range reflects a gradient of ecological condition and management risk within the Arid Karstic Woodlands & Shrublands biome.

Related Benchmarks

Other benchmarks in the AUS-AKW-CON-SOP family.

2 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
MaximumOnly Active v1
2 mg/kg Moderate
Conservation / Protected Natural Areas · Pristine Reference
MinimumOnly Active v1
20 mg/kg Moderate
Conservation / Protected Natural Areas · Conservation Target
MaximumOnly Active v1