Soil Potassium

AUS-AKW-CON-SOK General Moderate confidence

Benchmark Value

300 mg/kg

Thresholds: Lower: —, Upper: 300

Direction: Higher is desirable ↑

Form: UpperThreshold

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 3 benchmarks together — the OptimalRange form drives the primary score, while 2 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary Point Guard UpperThreshold Guard

Evidence & Context

A soil potassium level greater than 300 mg/kg can be considered an indicator of a system that has been pushed beyond its natural state, where the potential for detrimental ecological effects increases.

Metric Definition:

Upper detrimental threshold of available soil potassium above which negative ecological consequences increase.

Benchmark Definition:

Concentration of available soil potassium above which risks of nutrient imbalances and soil structural degradation increase.

Justification:

Based on agronomic data indicating luxury/excess potassium levels and ecological risks of nutrient imbalance and clay dispersion.

Sources (1)

Preview of Estimating woody vegetation cover in arid and semi-arid rangelands - Murdoch Research Portal, accessed July 12, 2025,

Estimating woody vegetation cover in arid and semi-arid rangelands - Murdoch Research Portal, accessed July 12, 2025, Journal

Agronomic and ecological studies on potassium excess effects

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

"Soil potassium-crop response calibration relationships and criteria for field crops grown in Australia"

Contextual Support Journal

"Soil potassium-crop response calibration relationships and criteria for field crops grown in Australia"

View Source

(PDF) Mineral Nutrition of Plants in Australia's Arid Zone - ResearchGate, accessed July 13, 2025

Contextual Support

(PDF) Mineral Nutrition of Plants in Australia's Arid Zone - ResearchGate

View Source

Context

Region Australia
Biome Arid Karstic Woodlands & Shrublands
Land Use Conservation / Protected Natural Areas
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 24 Mar 2026

Notes

Levels above this pose an increasing risk of negative system-level effects, including induced salinity stress, competitive inhibition of Ca/Mg uptake, and degradation of soil structure through clay dispersion.

Related Benchmarks

Other benchmarks in the AUS-AKW-CON-SOK family.