Soil Potassium

AUS-TMI-FOR-SOK General Moderate confidence

Benchmark Value

50 mg/kg
Thresholds: Lower: 50, Upper: —
Direction: Higher 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.

Evidence & Context

For sandy soils, potassium levels below 50 mg/kg are classified as 'Low'.

Metric Definition:

Available potassium level in soil below which forest health and long-term productivity are likely compromised

Benchmark Definition:

Critical lower threshold of available potassium in sandy soils for forest health and productivity in the Tropical & Subtropical Maritime Islands biome under Production Forestry land use.

Justification:

A level considered 'Low' for annual pasture systems is highly likely to represent a critical deficiency for a long-lived forest ecosystem.

Sources (2)

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Supporting Sources (38)

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
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Superseded
  • Version 1
  • Effective From 15 Mar 2026
  • Effective To 15 Mar 2026

Notes

Below this threshold, essential potassium-dependent functions would be significantly impaired.

Related Benchmarks

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

50 mg/kg Moderate
Production Forestry · Pristine Reference
MinimumOnly Active v2
250 mg/kg Moderate
Production Forestry · Pristine Reference · Clay loam soils
MaximumOnly Active v1
— mg/kg Moderate
Production Forestry · Target Condition
OptimalRange Active v1