Soil Potassium

AUS-TMI-FOR-SOK General Moderate confidence

Benchmark Value

250 mg/kg
Thresholds: Lower: —, Upper: 250
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

Levels of available potassium above 250 mg/kg are considered "High" even for more retentive clay loam soils.

Metric Definition:

Available potassium level in soil above which the system is considered artificially enriched and at risk of nutrient imbalances

Benchmark Definition:

Upper boundary of available potassium indicating artificial enrichment and potential nutrient imbalance in clay loam soils in the Tropical & Subtropical Maritime Islands biome under Production Forestry land use.

Justification:

An excessively high level of soil potassium indicates an artificially maintained agronomic system with risk of secondary nutrient imbalances.

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Additional references from the underlying research that informed this benchmark.

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Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Production Forestry
  • Assessment Pristine Reference
  • Vegetation Clay loam soils
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 15 Mar 2026

Notes

This upper boundary is a marker of artificiality and potential imbalance, rather than a direct toxicity threshold.

Related Benchmarks

Other benchmarks in the AUS-TMI-FOR-SOK family.

50 mg/kg Moderate
Production Forestry · Pristine Reference
MinimumOnly Active v2
— mg/kg Moderate
Production Forestry · Target Condition
OptimalRange Active v1
50 mg/kg Moderate
Production Forestry · Pristine Reference
MinimumOnly Superseded v1