Soil pH

AUS-AMR-AGR-SPH General Moderate confidence

Benchmark Value

No specific value — see range
Range: 6.5 to 7.5 pH
Optimal Range: 6.5 to 7.5
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

Soil pH 6.5 - 7.5 (for non-calcareous sandy/loamy soils) pH (water) Eyre Peninsula Farming Systems 2000 Summary Moderate Benchmark Rationale: This range is derived from real-world field measurements on sandy loam and loamy sand soils under active cropping in a comparable Australian semi-arid environment.

Metric Definition:

Topsoil pH measured in water (pH(water)) representing the best available condition of nature for agricultural crop production within Australia's Arid Mountain Ranges & Uplands biome.

Benchmark Definition:

Reference benchmark range for soil pH in non-calcareous sandy/loamy soils under sustainable cropping in Australian Arid Mountain Ranges & Uplands.

Justification:

This range is derived from real-world field measurements on sandy loam and loamy sand soils under active cropping in a comparable Australian semi-arid environment. It represents a 'best-on-offer' condition that sits squarely within the optimal ecological window, avoiding the key hazards of both aluminum toxicity and sodicity-induced soil structural decline.

Sources (1)

Preview of Eyre Peninsula Farming Systems Summary 2021
Eyre Peninsula Farming Systems Summary 2021 Journal

Eyre Peninsula Farming Systems Summary 2021

View Source

Supporting Sources (19)

Additional references from the underlying research that informed this benchmark.

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

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

View Source
Preview of Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 2, 2025,
Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 2, 2025,
Contextual Support Government

Northern and Yorke | Soil management - Landscape South Australia, accessed July 28, 2025

View Source
Preview of Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Contextual Support Journal

Root Structure and Functioning for Efficient Acquisition of Phosphorus: Matching Morphological and Physiological Traits

View Source
Preview of Balancing pasture development options for landscape diversity - CiteSeerX, accessed July 28, 2025
Balancing pasture development options for landscape diversity - CiteSeerX, accessed July 28, 2025
Contextual Support GreyLiterature

Balancing pasture development options for landscape diversity - CiteSeerX, accessed July 28, 2025

View Source
Preview of Discover the Top 6 Benefits of Regenerative Farming in Australia, accessed July 16, 2025
Discover the Top 6 Benefits of Regenerative Farming in Australia, accessed July 16, 2025
Contextual Support Journal

Soil Health: Supporting Rural Industries in the Wet Tropics, accessed August 28, 2025,

View Source
Preview of Farming more sustainably by managing soil acidity, accessed July 28, 2025,
Farming more sustainably by managing soil acidity, accessed July 28, 2025,
Contextual Support Journal

Soil pH Explained - Soil Quality Knowledge Base, accessed July 28, 2025

View Source
Preview of Investigating the impacts of groundwater on soil properties and ..., accessed July 28, 2025
Investigating the impacts of groundwater on soil properties and ..., accessed July 28, 2025
Contextual Support Journal

Investigating the impacts of groundwater on soil properties and ..., accessed July 28, 2025

View Source
Preview of Liming acidic soils creates profits, land use options but often more emissions - CSIRO Publishing
Liming acidic soils creates profits, land use options but often more emissions - CSIRO Publishing
Contextual Support Journal

The relationships between land management practices and soil condition and the quality of ecosystem services delivered from agri - DAFF, accessed August 28, 2025,

View Source
Preview of Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 5, 2025,
Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 5, 2025,
Contextual Support Journal

Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 28, 2025,

View Source
Preview of Soil Constraints in an Arid Environment—Challenges, Prospects, and Implications - MDPI, accessed July 6, 2025,
Soil Constraints in an Arid Environment—Challenges, Prospects, and Implications - MDPI, accessed July 6, 2025,
Contextual Support Journal

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

View Source
Preview of Soil pH - SA | Fact Sheets | soilquality.org.au
Soil pH - SA | Fact Sheets | soilquality.org.au
Contextual Support Government

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

View Source
Preview of Soil pH | Environment, land and water - Queensland Government, accessed July 30, 2025,
Soil pH | Environment, land and water - Queensland Government, accessed July 30, 2025,
Contextual Support Government

Improving Soil Structure and pH Levels (DPIFM_NT) - Department of ..., accessed July 20, 2025

View Source
Preview of Soil pH in northern and southern areas of the WA wheatbelt - DPIRD's Digital library, accessed July 28, 2025
Soil pH in northern and southern areas of the WA wheatbelt - DPIRD's Digital library, accessed July 28, 2025
Contextual Support Government

Soil pH in northern and southern areas of the WA wheatbelt - DPIRD's Digital library, accessed July 28, 2025

View Source
Preview of Soil Quality Knowledge Base. (n.d.). Soil pH.
Soil Quality Knowledge Base. (n.d.). Soil pH.
Contextual Support GreyLiterature

Working with bio-amendments: Insights from cropping farmers - Soils For Life, accessed July 7, 2025,

View Source
Preview of The extent of surface soil acidity in the relatively intensive... | Download Table - ResearchGate, accessed July 28, 2025
The extent of surface soil acidity in the relatively intensive... | Download Table - ResearchGate, accessed July 28, 2025
Contextual Support

Agricultural production system in arid and semi-arid regions, accessed August 28, 2025,

View Source
Preview of The pH of Australian soils: field results from a national survey - CSIRO Publishing, accessed July 25, 2025,
The pH of Australian soils: field results from a national survey - CSIRO Publishing, accessed July 25, 2025,
Contextual Support Journal

The pH of Australian soils: field results from a national survey - CSIRO Publishing, accessed August 28, 2025,

View Source
Preview of Tool 6.7 Soil health benchmarks and guidelines for managing problem soils, accessed July 28, 2025
Tool 6.7 Soil health benchmarks and guidelines for managing problem soils, accessed July 28, 2025
Contextual Support Journal

LawrieCo2 Soil Carbon Regeneration System, accessed July 28, 2025

View Source
Preview of Transforming Agriculture in the Pilbara: Newman managed aquifer recharge (MAR) feasibility assessment - CSIRO Research Publications Repository, accessed July 28, 2025
Transforming Agriculture in the Pilbara: Newman managed aquifer recharge (MAR) feasibility assessment - CSIRO Research Publications Repository, accessed July 28, 2025
Contextual Support GreyLiterature

Transforming Agriculture in the Pilbara: Newman managed aquifer recharge (MAR) feasibility assessment - CSIRO Research Publications Repository, accessed July 28, 2025

View Source
Preview of Water repellent soils - CSIRO
Water repellent soils - CSIRO
Contextual Support Government

Water repellent soils - CSIRO, accessed July 28, 2025

View Source

Context

  • Region Australia
  • Biome Arid Mountain Ranges & Uplands
  • Land Use Agricultural Crop Production
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 24 Mar 2026

Notes

Lower Critical Threshold: 4.8 pH. Upper Detrimental Threshold: 8.2 pH. Lower Critical Threshold: A pHCaCl2​​ < 4.8 is critically low, leading to aluminum toxicity, stunted root growth, and compromised ecosystem resilience, particularly to drought. Optimal Range: The optimal range for ecological health and sustainable production is a pHCaCl2​​ of 5.5 to 7.5. Upper Detrimental Threshold: A detrimental upper threshold exists where high pH is linked to sodicity, causing clay dispersion and soil structural collapse. This risk becomes significant at pH(water) > 8.2.

Related Benchmarks

Other benchmarks in the AUS-AMR-AGR-SPH family.

— pH Moderate
Agricultural Crop Production · Pristine Reference
OptimalRange Active v1