Soil Phosphorus

AUS-TDG-AGR-SOP General Moderate confidence

Benchmark Value

8 mg/kg

Direction: Higher is desirable ↑

Form: Point

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

A single reference value is requested for the benchmark. An Olsen P value of 8 mg/kg (0-10 cm soil depth) is proposed as a reference point for the best available condition.

Metric Definition:

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

Benchmark Definition:

Reference value for soil phosphorus representing the best available condition of nature achievable within sustainable agricultural crop production systems.

Justification:

This benchmark is an informed interpretation derived from related ecological studies (primarily native pastures) and the guiding principles of sustainable agriculture, acknowledging limited direct empirical evidence from long-term regenerative cropping systems.

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.

(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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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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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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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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www.agric.wa.gov.au

Contextual Support

www.agric.wa.gov.au

View Source

Context

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

Lifecycle

Status Active
Version 1
Effective From 24 Mar 2026

Notes

The value balances potential crop nutrient requirements with conditions favorable for native biodiversity and long-term soil health, and is substantially lower than typical agronomic optima.

Related Benchmarks

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