Soil Electrical Conductivity (EC)

AUS-AKW-AGR-SEC General Moderate confidence

Benchmark Value

0.38 dS/m

Thresholds: Lower: —, Upper: 4

Direction: Lower is desirable ↓

Form: MinimumOnly

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 24 benchmarks together — the OptimalRange form drives the primary score, while 23 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

A soil is formally defined as "saline" when its saturated paste electrical conductivity (ECe) is equal to or greater than 4.0 dS/m.

Metric Definition:

Soil Electrical Conductivity (EC) measured as the saturated paste extract (ECe)

Benchmark Definition:

This benchmark defines the soil electrical conductivity (EC) threshold at which soil is classified as saline in the Arid Karstic Woodlands biome under agricultural crop production.

Justification:

This value represents a clear and unambiguous threshold of degradation. At this level of salinity, osmotic stress becomes a significant factor for many crops, and the soil's chemical environment is fundamentally altered from a healthy state.

Sources (1)

Preview of Soil Electrical Conductivity - Natural Resources Conservation Service, accessed May 16, 2025,

Soil Electrical Conductivity - Natural Resources Conservation Service, accessed May 16, 2025, Journal

USDA 12

View Source

Supporting Sources (22)

Additional references from the underlying research that informed this benchmark.

(PDF) Soil processes affecting crop production in salt-affected soils - ResearchGate

Contextual Support Journal

(PDF) Soil processes affecting crop production in salt-affected soils - ResearchGate

View Source

Across The Nullarbor…….Western Australia at last! - Bob's Big Idea - WordPress.com, accessed July 23, 2025

Contextual Support GreyLiterature

Across The Nullarbor…….Western Australia at last! - Bob's Big Idea - WordPress.com

View Source

Preview of Approved Conservation Advice (including listing advice) for the Eucalypt Woodlands of the Western Australian Wheatbelt, accessed July 23, 2025

Approved Conservation Advice (including listing advice) for the Eucalypt Woodlands of the Western Australian Wheatbelt, accessed July 23, 2025

Contextual Support Journal

Eyre Peninsula Farming Systems Summary 2022 - Department of Primary Industries and Regions

View Source

Continuous cropping of a Calcarosol in a low-rainfall environment: effects of rotations and nitrogen fertiliser

Direct Evidence

Continuous cropping of a Calcarosol in a low-rainfall environment: effects of rotations and nitrogen fertiliser

View Source

Cutting hay at Nullarbor cattle station | Farm Weekly - video Dailymotion

Contextual Support GreyLiterature

Eyre Peninsula farming systems summaries - Department of Primary Industries and Regions South Australia - PIRSA

View Source

Eyre Peninsula Farming Systems Summary 2023 - Department of Primary Industries and Regions

Contextual Support Journal

Find out the Different Types of Soil in Australia - Kelly Tillage AUS, accessed July 7, 2025

View Source

Eyre Peninsula Farming Systems Summary 2024 - PIRSA

Contextual Support Journal

Eyre Peninsula Farming Systems Summary 2024 - PIRSA

View Source

Eyre Peninsula Regional Drought Resilience Plan

Contextual Support

Eyre Peninsula Regional Drought Resilience Plan

View Source

Preview of Full article: Estimating the electrical conductivity of a saturated soil paste extract (ECe) from 1:1(EC1:1), 1:2(EC1:2) and 1:5(EC1:5) soil:water suspension ratios, in calcareous soils from the Mediterranean Islands of Malta - Taylor & Francis Online

Full article: Estimating the electrical conductivity of a saturated soil paste extract (ECe) from 1:1(EC1:1), 1:2(EC1:2) and 1:5(EC1:5) soil:water suspension ratios, in calcareous soils from the Mediterranean Islands of Malta - Taylor & Francis Online

Methodology Source GreyLiterature

View Source

Karst | Geoscience Australia

Contextual Support GreyLiterature

Karst | Geoscience Australia

View Source

Karst wetlands - WetlandInfo, accessed July 26, 2025,

Contextual Support Journal

Karst wetlands - WetlandInfo, accessed July 26, 2025,

View Source

Nullarbor bioregion - DCCEEW, accessed July 27, 2025

Contextual Support Journal

(PDF) Soil potassium—crop response calibration relationships and ..., accessed July 24, 2025

View Source

Nullarbor Karst - The Western Australian Speleological Group, accessed July 26, 2025,

Contextual Support GreyLiterature

The Nullarbor deserves better protection - La Trobe University, accessed July 23, 2025

View Source

Nullarbor Plain - Wikipedia, accessed July 25, 2025,

Contextual Support GreyLiterature

Nullarbor Plain - Wikipedia, accessed July 24, 2025

View Source

Regenerative Agriculture - SOUTHERN SOILS

Contextual Support GreyLiterature

Regenerative Agriculture - SOUTHERN SOILS

View Source

Research on Soil Management and Conservation - MDPI

Contextual Support Journal

Salinity Tolerance in Wheat: Mechanisms and Breeding Approaches - MDPI

View Source

Salinity tolerance in wheat: rethinking the targets | Journal of Experimental Botany

Contextual Support

Salinity tolerance in wheat: rethinking the targets | Journal of Experimental Botany

View Source

Soil - RegenWA

Contextual Support GreyLiterature

Soil - RegenWA

View Source

Soil Carbon Sequestration Potential: A review for Australian agriculture - MLA, accessed August 5, 2025,

Contextual Support Journal

Spatial distribution of soil microbial activity and soil properties ..., accessed August 13, 2025,

View Source

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 The impact, identification and management of dispersive soils in rainfed cropping systems - UQ eSpace - The University of Queensland, accessed July 6, 2025,

The impact, identification and management of dispersive soils in rainfed cropping systems - UQ eSpace - The University of Queensland, accessed July 6, 2025,

Contextual Support Journal

Cover cropping impacts on soil water and carbon in dryland ...

View Source

Preview of What are some possible explanations for the lack of vegetation on the Nullarbor Plain of Western Australia? - Quora, accessed July 27, 2025

What are some possible explanations for the lack of vegetation on the Nullarbor Plain of Western Australia? - Quora, accessed July 27, 2025

Contextual Support GreyLiterature

What are some possible explanations for the lack of vegetation on the Nullarbor Plain of Western Australia? - Quora, accessed July 22, 2025

View Source

Context

Region Australia
Biome Arid Karstic Woodlands & Shrublands
Land Use Agricultural Crop Production
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 2
Effective From 19 Mar 2026

Notes

The formal classification for a saline soil. ConsistencyResolver applied 2026-03-23 00:20 UTC: BenchmarkValue 4 → (check: MinAboveOptimalHigh, rationale: Clearing BenchmarkValue to avoid duplication of threshold values and allow UpperThreshold to define the threshold.) ConsistencyResolver applied 2026-03-23 00:20 UTC: UpperThreshold → 4 (check: MinAboveOptimalHigh, rationale: The Notes state 'A soil is formally defined as saline when EC >= 4.0 dS/m', indicating this is an upper degradation limit. Moving the value to UpperThreshold will auto-correct the form to MaximumOnly, resolving the contradiction.) ConsistencyResolver applied 2026-03-23 00:20 UTC: BenchmarkValue 4 → 0.38 (check: MinAboveMax, rationale: Swapping values with MaximumOnly benchmark to correct threshold directions; 0.38 dS/m is the lower degradation floor, so MinimumOnly should have 0.38.)

Related Benchmarks

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