Soil Electrical Conductivity (EC)

AUS-TMI-CON-SEC General High confidence

Benchmark Value

0.4 dS/m

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

The upper detrimental threshold is set at >0.4 dS/m (EC1:5). This value corresponds to the upper limit of the "Low" salinity class in the CSIRO Pacific Islands manual. An EC value exceeding this level signifies that the system is accumulating salts beyond its natural leaching capacity.

Metric Definition:

Soil Electrical Conductivity (EC1:5) measured in a 1:5 soil:water suspension

Benchmark Definition:

This benchmark marks the upper detrimental threshold for soil electrical conductivity, indicating the onset of salinisation and ecosystem degradation in conservation areas of Australia's Tropical & Subtropical Maritime Islands biome.

Justification:

Supported by CSIRO manual and international standards marking the point where salt accumulation causes stress to native flora.

Sources (2)

Soil Analysis Methods and Results Interpretation ... - CSIRO Research Journal

Soil Analysis Methods and Results Interpretation ... - CSIRO Research

View Source

Preview of www.publications.qld.gov.au, accessed May 16, 2025,

www.publications.qld.gov.au, accessed May 16, 2025, Journal

Measuring soil salinity - The Australian Wine Research Institute

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Soil Research - CSIRO PUBLISHING, accessed May 16, 2025,

Contextual Support Journal

Litchfield Savanna BASE Contextual, Soil Physico-Chemical Data ..., accessed May 20, 2025,

View Source

Wet Tropics region GLM land types - FutureBeef

Contextual Support GreyLiterature

Wet Tropics region GLM land types - FutureBeef

View Source

Context

Region Australia
Biome Tropical & Subtropical Maritime Islands
Land Use Conservation / Protected Natural Areas
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 2
Effective From 7 Jun 2026

Notes

Exceeding this threshold indicates transition to saline state and degradation from saltwater intrusion. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TMI-CON-SEC family.