Soil Structure & Compaction

AUS-AKW-AGR-SSC General Moderate confidence

Benchmark Value

1500 kPa

Direction: Lower is desirable ↓

Form: MaximumOnly

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 14 benchmarks together — the OptimalRange form drives the primary score, while 13 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary LowerThreshold Guard MaximumOnly Guard UpperThreshold Guard MaximumOnly Guard MaximumOnly Guard Point Guard MaximumOnly Guard MinimumOnly Guard MinimumOnly Guard MaximumOnly Guard MinimumOnly Guard MaximumOnly Guard MinimumOnly Guard

Evidence & Context

Reference Value: < 1500 kPaA soil that consistently measures below 1500 kPa (when tested at field capacity) is considered to be in a high state of health for this indicator.

Metric Definition:

Penetration resistance or soil strength measured by a cone penetrometer, indicating the force required to push a standard-sized cone through the soil profile.

Benchmark Definition:

This benchmark represents the maximum soil penetration resistance below which soil compaction does not limit root growth or ecological function in arid karstic woodlands under agricultural crop production.

Justification:

This value is selected as it is the most widely cited and defensible threshold for the onset of root impedance in agricultural soils.

Sources (2)

Preview of Nutrition on calcareous soils and deep P placement - GRDC

Nutrition on calcareous soils and deep P placement - GRDC

Preview of Subsurface compaction; Soil Compaction and Root Growth: A Review; Nutrition on calcareous soils and deep P placement

Subsurface compaction; Soil Compaction and Root Growth: A Review; Nutrition on calcareous soils and deep P placement Government

Subsurface Compaction - NSW | Fact Sheets | soilquality.org.au, accessed July 27, 2025

Supporting Sources (19)

Additional references from the underlying research that informed this benchmark.

Preview of CRITICAL LIMITS OF SOIL PENETRATION RESISTANCE ... - Scielo

CRITICAL LIMITS OF SOIL PENETRATION RESISTANCE ... - Scielo

Contextual Support Journal

Nutrition on calcareous soils and deep P placement - GRDC, accessed July 22, 2025

Preview of Effect of combined soil water and external load on soil compaction - CSIRO Publishing, accessed July 7, 2025,

Effect of combined soil water and external load on soil compaction - CSIRO Publishing, accessed July 7, 2025,

Contextual Support Journal

What is Regenerative Agriculture? - Soils For Life, accessed July 22, 2025

Preview of Eyre Peninsula Farming Systems Summary 2023 - Department of Primary Industries and Regions, accessed July 22, 2025,

Eyre Peninsula Farming Systems Summary 2023 - Department of Primary Industries and Regions, accessed July 22, 2025,

Contextual Support Government

Victorian Grain Cropping Soils - Calcarosols | VRO | Agriculture Victoria

Preview of Increasing production on sandy soils in low and medium rainfall areas of the Southern Region | AIR EP, accessed July 22, 2025,

Increasing production on sandy soils in low and medium rainfall areas of the Southern Region | AIR EP, accessed July 22, 2025,

Contextual Support

Increasing production on sandy soils in low and medium rainfall areas of the Southern Region | AIR EP, accessed July 22, 2025

Preview of Innovative roots ripping process to protect Australia's arid woodlands - YouTube, accessed July 22, 2025,

Innovative roots ripping process to protect Australia's arid woodlands - YouTube, accessed July 22, 2025,

Contextual Support GreyLiterature

Innovative roots ripping process to protect Australia's arid woodlands - YouTube, accessed July 22, 2025

Preview of Karst and agriculture in Australia - Digital Commons @ USF, accessed July 22, 2025,

Karst and agriculture in Australia - Digital Commons @ USF, accessed July 22, 2025,

Contextual Support Government

Alluvial Gully Erosion Rates and Processes Across the Mitchell ...

Preview of New insights into high soil strength and crop plants; implications for grain crop production in the Australian environment - ResearchGate, accessed August 4, 2025,

New insights into high soil strength and crop plants; implications for grain crop production in the Australian environment - ResearchGate, accessed August 4, 2025,

Contextual Support GreyLiterature

Using acidic sand to detoxify subsoil boron - Grower Group Alliance, accessed July 22, 2025

Preview of Nullarbor Plain - Wikipedia, accessed July 25, 2025,

Nullarbor Plain - Wikipedia, accessed July 25, 2025,

Contextual Support GreyLiterature

Nullarbor Plain - Wikipedia, accessed July 24, 2025

Preview of Q1. Identifying calcareous soil - Soils Connect, accessed July 22, 2025,

Q1. Identifying calcareous soil - Soils Connect, accessed July 22, 2025,

Contextual Support Journal

Q1. Identifying calcareous soil - Soils Connect, accessed July 22, 2025

Preview of Regenerative Agriculture Australia: Benefits and Practices - SONIC Natural Farming, accessed July 22, 2025,

Regenerative Agriculture Australia: Benefits and Practices - SONIC Natural Farming, accessed July 22, 2025,

Contextual Support GreyLiterature

More profitable crops on highly calcareous soils by improving early vigour and overcoming soil constraints | AIR EP

Preview of Resistance and resilience of the forest soil microbiome to logging-associated compaction, accessed August 2, 2025,

Resistance and resilience of the forest soil microbiome to logging-associated compaction, accessed August 2, 2025,

Contextual Support Journal

A Review of the Effects of Soil Compaction and Amelioration Treatments on Landscape Trees | Arboriculture & Urban Forestry, accessed July 22, 2025

Preview of Soil compaction | UMN Extension, accessed July 30, 2025,

Soil compaction | UMN Extension, accessed July 30, 2025,

Contextual Support Government

Soil compaction | UMN Extension, accessed July 22, 2025

Preview of Soil compaction and the architectural plasticity of root systems - PMC, accessed July 22, 2025,

Soil compaction and the architectural plasticity of root systems - PMC, accessed July 22, 2025,

Methodology Source GreyLiterature

Soil compaction and the architectural plasticity of root systems - PMC, accessed July 22, 2025

Preview of Soil Compaction in Agricultural Production | Pioneer® Seeds, accessed August 4, 2025,

Soil Compaction in Agricultural Production | Pioneer® Seeds, accessed August 4, 2025,

Contextual Support GreyLiterature

Soil Health Assessment Part IV: Soil Penetration Resistance and Plant Roots – Soil and Water Conservation Laboratory Manual - New Prairie Press Open Book Publishing, accessed July 22, 2025

Preview of Soil Inorganic Carbon, the Other and Equally Important Soil Carbon Pool: Distribution, Controlling Factors, and the Impact of C, accessed July 26, 2025

Soil Inorganic Carbon, the Other and Equally Important Soil Carbon Pool: Distribution, Controlling Factors, and the Impact of C, accessed July 26, 2025

Contextual Support GreyLiterature

Chapter 5, accessed July 22, 2025

Preview of Soil management - Landscape South Australia - Eyre Peninsula, accessed July 13, 2025

Soil management - Landscape South Australia - Eyre Peninsula, accessed July 13, 2025

Contextual Support Government

Soil management - Landscape South Australia - Eyre Peninsula, accessed July 22, 2025

Preview of Understanding the impacts of farming practices on the soil microbiome as a sustainable approach to crop production. - CSIRO Research, accessed July 9, 2025

Understanding the impacts of farming practices on the soil microbiome as a sustainable approach to crop production. - CSIRO Research, accessed July 9, 2025

Contextual Support Government

COMPARISON OF TWO TILLAGE PRACTICES ON A SEMI-ARID, accessed July 22, 2025

Preview of Understanding the properties of South Australian agricultural soils.1 - Department for Environment and Water, accessed July 22, 2025,

Understanding the properties of South Australian agricultural soils.1 - Department for Environment and Water, accessed July 22, 2025,

Contextual Support Journal

Understanding the properties of South Australian agricultural soils.1 - Department for Environment and Water, accessed July 22, 2025

Preview of What is Regenerative Agriculture? - Soils For Life, accessed August 4, 2025,

What is Regenerative Agriculture? - Soils For Life, accessed August 4, 2025,

Contextual Support GreyLiterature

Why soils are so important for regenerative agriculture - Soils For Life, accessed July 22, 2025

Context

Region Australia
Biome Arid Karstic Woodlands & Shrublands
Land Use Agricultural Crop Production
Assessment Not Stated
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 7 Jun 2026

Notes

No upper detrimental threshold — higher values are always worse for root growth and soil health. This benchmark represents a state where soil compaction is not a primary limiting factor for root growth and ecological function, measured at field capacity. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-AKW-AGR-SSC family.