Soil Electrical Conductivity (EC)

AUS-TMS-CON-SEC General High confidence

Benchmark Value

No specific value — see range
Thresholds: Lower: —, Upper: 0.2
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 10 benchmarks together — the OptimalRange form drives the primary score, while 9 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary OptimalRange Guard MaximumOnly Guard OptimalRange Guard Point Guard MaximumOnly Guard OptimalRange Guard MinimumOnly Guard OptimalRange Guard MaximumOnly Guard

Evidence & Context

Proposed Upper Detrimental Threshold: An EC1:5 value consistently > 0.20 dS/m (corresponding to an estimated ECe > ~2.0-2.4 dS/m, depending on precise texture and conversion factor) is proposed as an upper detrimental threshold for Australian Tropical Monsoonal Savannas in conservation areas.

Metric Definition:

Soil Electrical Conductivity measured as EC1:5 (1:5 soil/water extract)

Benchmark Definition:

This benchmark defines the upper detrimental threshold for soil electrical conductivity in Australian Tropical Monsoonal Savannas conservation areas, above which ecological harm to native flora and ecosystem integrity is likely.

Justification:

This threshold signifies a significant departure from the natural baseline. Levels above this point are likely to impose physiological stress on the typically salt-sensitive native flora, potentially alter species composition, and compromise overall ecosystem integrity.

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 (2)

Additional references from the underlying research that informed this benchmark.

Preview of Rance, S.J., et al. (2024). Nutrient limitations to plantation tree growth on three contrasting low fertility soils in the Northern Territory, Australia. Soil Research, SR23128.
Rance, S.J., et al. (2024). Nutrient limitations to plantation tree growth on three contrasting low fertility soils in the Northern Territory, Australia. Soil Research, SR23128.
Contextual Support Journal

Rance, S.J., et al. (2024). Nutrient limitations to plantation tree growth on three contrasting low fertility soils in the Northern Territory, Australia. Soil Research, SR23128.

View Source
Preview of TERN AusPlots soil data from Kakadu National Park.
TERN AusPlots soil data from Kakadu National Park.
Direct Evidence

TERN AusPlots soil data from Kakadu National Park.

View Source

Context

  • Region Australia
  • Biome Tropical Monsoonal Savannas
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Evidence Type DegradationThreshold

Lifecycle

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

Notes

Sustained EC1:5 values exceeding 0.20 dS/m are considered to indicate a potential for ecological detriment. ConsistencyResolver applied 2026-03-24 19:53 UTC: BenchmarkValue 0.2 → (check: MinAboveOptimalHigh, rationale: Clearing BenchmarkValue after moving the threshold to UpperThreshold to avoid duplication and ensure correct threshold field usage.) ConsistencyResolver applied 2026-03-24 19:53 UTC: UpperThreshold → 0.2 (check: MinAboveOptimalHigh, rationale: The Notes state 'Sustained EC1:5 values exceeding 0.20 dS/m are considered to indicate a potential for ecological detriment,' indicating this is an upper threshold. Moving the value to UpperThreshold will auto-correct the form to MaximumOnly, resolving the MinAboveOptimalHigh contradiction.) [Auto-corrected BenchmarkForm: MinimumOnly → MaximumOnly] ConsistencyResolver applied 2026-03-24 19:54 UTC: BenchmarkValue 0.2 → (check: MinAboveOptimalHigh, rationale: Clearing BenchmarkValue after moving the threshold to UpperThreshold to avoid duplication and clarify the threshold field.) ConsistencyResolver applied 2026-03-24 19:54 UTC: UpperThreshold → 0.2 (check: MinAboveOptimalHigh, rationale: The Notes state 'Sustained EC1:5 values exceeding 0.20 dS/m indicate ecological detriment,' confirming this is an upper degradation limit. Moving the value to UpperThreshold will auto-correct the form to MaximumOnly, resolving the contradiction.)

Related Benchmarks

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

— dS/m High
Conservation / Protected Natural Areas · Pristine Reference
OptimalRange Active v1