Soil pH

Benchmark Value

No specific value — see range

Range: 7.5 to 9 pH

Optimal Range: 7.5 to 9

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

A representative range for the topsoil in a healthy, natural state is pH 7.5 – 9.0.

Metric Definition:

Soil pH range for Calcarosols topsoil in natural healthy state.

Benchmark Definition:

Natural pH range for Calcarosols topsoil in the biome.

Justification:

Based on published literature and soil profile data.

Sources (1)

Preview of Australian Soil Classification edition 3 - CALCAROSOLS

Australian Soil Classification edition 3 - CALCAROSOLS Government

Soil Characteristics and Management Options | VRO - Victorian Resources Online

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Supporting Sources (9)

Additional references from the underlying research that informed this benchmark.

(PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025,

Direct Evidence Journal

Soil pH | Environment, land and water - Queensland Government, accessed August 28, 2025,

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ASC - VERTOSOLS - Soil Science Australia

Contextual Support

What are the optimum nutrient targets for pastures? - Soil Health Knowledgebase

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Ecological impacts of flood mitigation and drainage in coastal lowlands - AustLII

Contextual Support

Ecological impacts of flood mitigation and drainage in coastal lowlands - AustLII

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National Guidance on Acid Sulfate Soils - Water Quality Australia

Contextual Support Journal

Managing soils - Department of Primary Industries and Regional Development

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Soil Constraints in an Arid Environment - Encyclopedia.pub

Contextual Support GreyLiterature

Soil Constraints in an Arid Environment - Encyclopedia.pub, accessed July 27, 2025,

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Soil pH - SA | Fact Sheets | soilquality.org.au

Contextual Support Government

Soil pH - SA | Fact Sheets | soilquality.org.au, accessed July 30, 2025,

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Victorian Resources Online | Resources | Support and resources ...

Contextual Support Government

Structural controls on the orientation of erosion gullies in mid-western New South Wales, Australia, accessed July 22, 2025

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Water and sediment quality in the Diamantina-Georgina River ..., accessed July 21, 2025,

Contextual Support Journal

Water and sediment quality in the Diamantina-Georgina River ..., accessed July 21, 2025,

View Source

Water and sediment quality in the Diamantina-Georgina River catchment, Lake Eyre Basin

Direct Evidence Journal

Water quality in the Georgina-Diamantina River catchment

View Source

Benchmark Value

Scoring Curve

Evidence & Context

Sources (1)

Supporting Sources (9)

Context

Lifecycle

Notes

Related Benchmarks