Soil Potassium

AUS-AMR-CON-SOK General Moderate confidence

Benchmark Value

No specific value — see range
Range: 100 to 200 mg/kg
Optimal Range: 100 to 200
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 reference value is 100 - 200 mg/kg for Sandy soils as the optimal range for available potassium in conservation landscapes.

Metric Definition:

Available soil potassium measured by the Colwell K test, expressed in mg/kg

Benchmark Definition:

This benchmark defines the optimal range of available soil potassium for conservation landscapes with sandy soils in the Arid Mountain Ranges & Uplands biome, indicating healthy ecosystem function and resilience.

Justification:

This benchmark represents an inferred value for high ecosystem health and resilience, based on sustainable pasture systems as analogues for perennial native ecosystems and supported by evidence of potassium depletion following land use change.

Sources (1)

Preview of Understanding soil tests for pastures | Soil | Farm management ..., accessed May 12, 2025
Understanding soil tests for pastures | Soil | Farm management ..., accessed May 12, 2025 Government

Understanding soil tests for pastures

View Source

Supporting Sources (38)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Mineral Nutrition of Plants in Australia's Arid Zone - ResearchGate, accessed July 13, 2025
(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
Preview of (PDF) Soil potassium—crop response calibration relationships and criteria for field crops grown in Australia - ResearchGate, accessed July 18, 2025,
(PDF) Soil potassium—crop response calibration relationships and criteria for field crops grown in Australia - ResearchGate, accessed July 18, 2025,
Contextual Support Journal

The Western Australian Rangeland Monitoring System (WARMS) – operating a regional scale monitoring system - ResearchGate, accessed July 24, 2025

View Source
Preview of 15 fascinating facts about the Flinders Ranges - Department for Environment and Water, accessed August 2, 2025,
15 fascinating facts about the Flinders Ranges - Department for Environment and Water, accessed August 2, 2025,
Contextual Support Government

FLC Flinders Chase Land System

View Source
Preview of Accessing disparate soil data | TERN Australia
Accessing disparate soil data | TERN Australia
Contextual Support Government

Accessing disparate soil data - TERN Australia

View Source
Preview of Alice Mulga SuperSite | Soil & Vegetation Monitoring - TERN Australia, accessed July 22, 2025,
Alice Mulga SuperSite | Soil & Vegetation Monitoring - TERN Australia, accessed July 22, 2025,
Contextual Support Government

Great Western Woodlands, Ground Water Data, 2014 - TERN Data Discovery Portal, accessed July 10, 2025,

View Source
Preview of Australia - Soils, Climate, Erosion | Britannica
Australia - Soils, Climate, Erosion | Britannica
Contextual Support GreyLiterature

SOIL TESTING, accessed August 1, 2025

View Source
Preview of Comment: Potassium in soil is running low, threatening global food security - study proposes way out | UCL News - UCL – University College London
Comment: Potassium in soil is running low, threatening global food security - study proposes way out | UCL News - UCL – University College London
Contextual Support GreyLiterature

Comment: Potassium in soil is running low, threatening global food security - study proposes way out | UCL News - UCL – University College London

View Source
Preview of Comment: Potassium in soil is running low, threatening global food security - study proposes way out | UCL News - UCL – University College London, accessed August 11, 2025,
Comment: Potassium in soil is running low, threatening global food security - study proposes way out | UCL News - UCL – University College London, accessed August 11, 2025,
Contextual Support GreyLiterature

Living with high potassium: Balance between nutrient acquisition and K-induced salt stress signaling

View Source
Preview of Comparison of soil analytical methods for estimating plant-available potassium in highly weathered soils - CSIRO Publishing
Comparison of soil analytical methods for estimating plant-available potassium in highly weathered soils - CSIRO Publishing
Methodology Source Journal

Crop and Pasture Science - CSIRO PUBLISHING

View Source
Preview of Crop and Pasture Science - CSIRO PUBLISHING, accessed July 10, 2025
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
Preview of Digital soil mapping of key soil properties over New South Wales - NSW Government
Digital soil mapping of key soil properties over New South Wales - NSW Government
Contextual Support Government

Digital soil mapping of key soil properties over New South Wales - NSW Government

View Source
Preview of Flinders Ranges - UNESCO World Heritage Centre, accessed July 29, 2025,
Flinders Ranges - UNESCO World Heritage Centre, accessed July 29, 2025,
Contextual Support Government

Flinders Ranges - UNESCO World Heritage Centre, accessed July 28, 2025,

View Source
Preview of Flinders Ranges - Wikipedia, accessed August 2, 2025,
Flinders Ranges - Wikipedia, accessed August 2, 2025,
Contextual Support GreyLiterature

Geol ogy ofth e Flin ders Rang es Nati onal Park

View Source
Preview of Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain p - Murdoch Research Portal
Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain p - Murdoch Research Portal
Contextual Support Journal

What are the optimum nutrient targets for pastures? - Soil Health Knowledgebase

View Source
Preview of Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - BioOne Complete, accessed July 10, 2025
Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - BioOne Complete, 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 | Crop and Pasture Science, accessed July 24, 2025

View Source
Preview of MacDonnell Ranges - Wikipedia
MacDonnell Ranges - Wikipedia
Contextual Support GreyLiterature

Desertification in Australia: Definition, Causes and Environmental Impact - Access EP, accessed July 31, 2025

View Source
Preview of MacDonnell Ranges Geology - SciArt
MacDonnell Ranges Geology - SciArt
Contextual Support GreyLiterature

A Dive into the Geological History of the Red Centre - Tourism Central Australia

View Source
Preview of MAGNESIUM - Incitec Pivot Fertilisers
MAGNESIUM - Incitec Pivot Fertilisers
Contextual Support Journal

Soil potassium relationships, uptake efficiency and availability for six distinctive soils in central and southern New South Wales, Australia - CSIRO PUBLISHING | Soil Research

View Source
Preview of Monitoring and forecasting drought through the assimilation of satellite water observations Siyuan Tian - ANU Open Research
Monitoring and forecasting drought through the assimilation of satellite water observations Siyuan Tian - ANU Open Research
Contextual Support Government

Soil and Landscape Grid of Australia - esoil.io

View Source
Preview of Plant nutrients in the soil - NSW Department of Primary Industries, accessed July 18, 2025,
Plant nutrients in the soil - NSW Department of Primary Industries, accessed July 18, 2025,
Contextual Support Government

Rangelands Living Skin | .Meat & Livestock Australia - MLA, accessed July 28, 2025,

View Source
Preview of Plantation tree growth responses to P, N, K and minor and trace elements on low fertility savanna soils - CSIRO Publishing
Plantation tree growth responses to P, N, K and minor and trace elements on low fertility savanna soils - CSIRO Publishing
Contextual Support Journal

Plantation tree growth responses to P, N, K and minor and trace elements on low fertility savanna soils - CSIRO Publishing

View Source
Preview of Potassium | Fact Sheets | soilquality.org.au
Potassium | Fact Sheets | soilquality.org.au
Contextual Support Government

Potassium | Fact Sheets | soilquality.org.au

View Source
Preview of Potassium and sulphur - emerging deficiencies in the southern region - GRDC, accessed July 13, 2025
Potassium and sulphur - emerging deficiencies in the southern region - GRDC, accessed July 13, 2025
Contextual Support Government

Potassium and sulphur - emerging deficiencies in the southern region - GRDC

View Source
Preview of Potassium to Magnesium Ratio - Plant Nutrition - Yara Canada
Potassium to Magnesium Ratio - Plant Nutrition - Yara Canada
Contextual Support GreyLiterature

Optimal potassium to magnesium ratio in soils ? | ResearchGate

View Source
Preview of Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses - MDPI
Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses - MDPI
Contextual Support Journal

Potassium Control of Plant Functions: Ecological and Agricultural Implications - MDPI

View Source
Preview of Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses - MDPI, accessed July 13, 2025
Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses - MDPI, accessed July 13, 2025
Contextual Support Journal

Potassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses - MDPI, accessed July 28, 2025,

View Source
Preview of SLGA: Soil and Landscape Grid of Australia (Soil Attributes) | Earth Engine Data Catalog
SLGA: Soil and Landscape Grid of Australia (Soil Attributes) | Earth Engine Data Catalog
Contextual Support Journal

Soil and Landscape Grid National Soil Attribute Maps - Total Nitrogen (3" resolution) - Release 2 - CSIRO Data Access Portal, accessed July 13, 2025,

View Source
Preview of SLGA: Soil and Landscape Grid of Australia (Soil Attributes) | Earth Engine Data Catalog, accessed July 30, 2025,
SLGA: Soil and Landscape Grid of Australia (Soil Attributes) | Earth Engine Data Catalog, accessed July 30, 2025,
Contextual Support

Soil and Landscape Grid National Soil Attribute Maps - Cation Exchange Capacity (3" resolution) - Release 1 - Research Data Australia

View Source
Preview of Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,
Soil and Landscape Grid of Australia - CSIRO, accessed July 30, 2025,
Contextual Support

Soil and Landscape Grid of Australia - CSIRO, accessed August 1, 2025

View Source
Preview of Soil Constraints in an Arid Environment—Challenges, Prospects, and Implications - MDPI, accessed July 6, 2025,
Soil Constraints in an Arid Environment—Challenges, Prospects, and Implications - MDPI, accessed July 6, 2025,
Contextual Support Journal

Soil pH | Environment, land and water - Queensland Government, accessed July 28, 2025

View Source
Preview of Soil health stocktake Queensland - GRDC, accessed May 11, 2025,
Soil health stocktake Queensland - GRDC, accessed May 11, 2025,
Contextual Support Government

Soil health stocktake Queensland - GRDC, accessed July 28, 2025,

View Source
Preview of Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA, accessed May 13, 2025,
Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA, accessed May 13, 2025,
Contextual Support GreyLiterature

Understanding soil tests for pastures | Soil | Farm management ..., accessed July 17, 2025,

View Source
Preview of Soil potassium—crop response calibration relationships and criteria for field crops grown in Australia - CSIRO PUBLISHING | Crop and Pasture Science
Soil potassium—crop response calibration relationships and criteria for field crops grown in Australia - CSIRO PUBLISHING | Crop and Pasture Science
Contextual Support Journal

Review and Synthesis of Potassium Dynamics and Crop Response in Australian Agriculture

View Source
Preview of Subsoil testing required to detect the rundown of soil potassium to deficient levels for wheat production on loam-textured soils - ResearchGate, accessed July 13, 2025
Subsoil testing required to detect the rundown of soil potassium to deficient levels for wheat production on loam-textured soils - ResearchGate, accessed July 13, 2025
Contextual Support Journal

Subsoil testing required to detect the rundown of soil potassium to deficient levels for wheat production on loam-textured soils - ResearchGate

View Source
Preview of Terrestrial Ecosystem Research Network TERN Australia - Queensland science, accessed July 30, 2025,
Terrestrial Ecosystem Research Network TERN Australia - Queensland science, accessed July 30, 2025,
Contextual Support Government

TERN Ecosystem Research Infrastructure | School of Biological Sciences

View Source
Preview of The Dynamics of Potassium in some Australian soils - ResearchGate
The Dynamics of Potassium in some Australian soils - ResearchGate
Contextual Support GreyLiterature

The Dynamics of Potassium in some Australian soils - ResearchGate, accessed July 24, 2025

View Source
Preview of Under the radar: Potassium on loamy soil - SoilsWest
Under the radar: Potassium on loamy soil - SoilsWest
Contextual Support GreyLiterature

Under the radar: Potassium on loamy soil - SoilsWest

View Source
Preview of V*. Clearing and burning brigalow (Acacia harpophylla) in Queensland, Australia, temporarily increases surface soil fertility prior to nutrient decline under cropping or grazing, accessed August 11, 2025,
V*. Clearing and burning brigalow (Acacia harpophylla) in Queensland, Australia, temporarily increases surface soil fertility prior to nutrient decline under cropping or grazing, accessed August 11, 2025,
Contextual Support Journal

V*. Clearing and burning brigalow (Acacia harpophylla) in Queensland, Australia, temporarily increases surface soil fertility prior to nutrient decline under cropping or grazing - CSIRO Publishing, accessed July 18, 2025,

View Source

Context

  • Region Australia
  • Biome Arid Mountain Ranges & Uplands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Conservation Target
  • Evidence Type ReferenceCondition

Lifecycle

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

Notes

Upper Detrimental Threshold: There is no evidence of direct K toxicity. The upper limit is defined by nutrient imbalance, specifically when the exchangeable K to Magnesium (Mg) ratio exceeds approximately 0.4, or when K saturation exceeds 10% of the Cation Exchange Capacity (CEC), which can induce Mg deficiency.

Related Benchmarks

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

— mg/kg Moderate
Conservation / Protected Natural Areas · Conservation Target
OptimalRange Active v1
— mg/kg Moderate
Conservation / Protected Natural Areas · Conservation Target
OptimalRange Active v1
— mg/kg Moderate
Conservation / Protected Natural Areas · Conservation Target
OptimalRange Active v1