Soil Potassium

AUS-AIF-FOR-SOK General Low confidence

Benchmark Value

No specific value — see range

Range: 150 to 210 mg/kg

Optimal Range: 150 to 210

Direction: Higher is desirable ↑

Form: OptimalRange

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.

Evidence & Context

The optimal range for loamy soils is therefore proposed as 150 – 210 mg/kg.

Metric Definition:

Available soil potassium concentration in loam soils measured as exchangeable potassium or equivalent method.

Benchmark Definition:

This benchmark defines the optimal range of available potassium in loam soils that supports sustainable forestry in the arid inland floodplains biome.

Justification:

Derived from Goulburn Broken CMA target range of 0.38-0.54 cmol(+)/kg for loam soils.

Sources (1)

Understanding Your Soil Test (Goulburn Broken CMA, 2016) Journal

Understanding Your Soil Test (Goulburn Broken CMA, 2016)

View Source

Supporting Sources (5)

Additional references from the underlying research that informed this benchmark.

Crop and Pasture Science - CSIRO PUBLISHING, accessed July 10, 2025

Contextual Support Journal

Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - CSIRO Publishing, accessed July 17, 2025

View Source

NSW Department of Primary Industries

Contextual Support GreyLiterature

NSW Department of Primary Industries guidelines for pasture legumes on clay loam soils

View Source

Potassium | Fact Sheets | soilquality.org.au, accessed August 11, 2025,

Direct Evidence Government

Potassium | Fact Sheets | soilquality.org.au

View Source

Potassium for crop production | UMN Extension

Contextual Support Government

Potassium for crop production | UMN Extension

View Source

Preview of Potassium limitation of forest productivity – Part 1: A mechanistic model simulating the effects of potassium availability on canopy carbon and water fluxes in tropical eucalypt stands - BG

Potassium limitation of forest productivity – Part 1: A mechanistic model simulating the effects of potassium availability on canopy carbon and water fluxes in tropical eucalypt stands - BG

Contextual Support GreyLiterature

Potassium limitation of forest productivity – Part 1: A mechanistic model simulating the effects of potassium availability on canopy carbon and water fluxes in tropical eucalypt stands - BG

View Source

Context

Region Australia
Biome Arid Inland Floodplains & Ephemeral River Systems
Land Use Production Forestry
Assessment Conservation Target
Vegetation Forest
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 9 Jun 2026

Notes

This range supports 90-95% of potential pasture yield and is a proxy for high ecosystem health in loam soils.

Related Benchmarks

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