Soil Structure & Compaction

AUS-TMI-LVG-SSC General Moderate confidence

Benchmark Value

3000 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.

Evidence & Context

A CSIRO study investigating compaction in Australian sandy soils found that radiata pine root penetration was "severely restricted" above a critical resistance of about 3000 kPa (3.0 MPa).

Metric Definition:

Penetrometer resistance value indicating severe restriction to root penetration in sandy soils.

Benchmark Definition:

This benchmark defines the critical soil compaction threshold for sandy soils in tropical and subtropical maritime islands under livestock grazing, beyond which root growth is severely restricted.

Justification:

This value provides an upper-end limit for coarse-textured soils where root growth is severely restricted.

Sources (1)

Preview of Soil Compaction - Natural Resources Conservation Service

Soil Compaction - Natural Resources Conservation Service Journal

Soil Research - CSIRO PUBLISHING

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Review Paper AS THE SOIL RESISTANCE TO PENETRATION AFFECTS THE DEVELOPMENT OF AGRICULTURAL CROPS?

Direct Evidence Journal

Review Paper AS THE SOIL RESISTANCE TO PENETRATION AFFECTS THE DEVELOPMENT OF AGRICULTURAL CROPS?

View Source

Soil health - Penetrometer - Department for Environment and Water, accessed August 2, 2025,

Direct Evidence Journal

Soil health - Department for Environment and Water

View Source

Soil Research - CSIRO PUBLISHING, accessed July 19, 2025,

Direct Evidence Journal

Comparing the effects of continuous and time-controlled grazing systems on soil characteristics in Southeast Queensland - CSIRO Publishing

View Source

Context

Region Australia
Biome Tropical & Subtropical Maritime Islands
Land Use Livestock Grazing & Pasture
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 7 Jun 2026

Notes

This threshold is specific to sandy soils and represents severe compaction limiting root growth. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TMI-LVG-SSC family.