Soil Potassium

AUS-TSW-AGR-SOK General Moderate confidence

Benchmark Value

120 mg/kg
Direction: Higher is desirable ↑
Form: Point

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 5 benchmarks together — the OptimalRange form drives the primary score, while 4 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary Point Guard MinimumOnly Guard MaximumOnly Guard Point Guard

Evidence & Context

The selection of a single benchmark value for soil potassium representing the "best available condition" requires a synthesis of the multifaceted roles this nutrient plays in the temperate semi-arid agroecosystem.

Metric Definition:

Colwell K test value representing plant-available potassium in soil

Benchmark Definition:

A benchmark value for soil potassium representing the best available condition under sustainable agricultural management in temperate semi-arid cropping systems.

Justification:

This value is justified because it is functionally optimal, restorative, biologically ambitious, and safe and balanced, supporting ecosystem resilience and counteracting historical potassium depletion.

Sources (1)

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 Journal

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

View Source

Supporting Sources (15)

Additional references from the underlying research that informed this benchmark.

Preview of 1301.0 - ABS Feature Articles, 1966 - Australian Bureau of Statistics
1301.0 - ABS Feature Articles, 1966 - Australian Bureau of Statistics
Contextual Support Journal

1301.0 - ABS Feature Articles, 1966 - Australian Bureau of Statistics

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
Contextual Support Journal

EFFECTS OF AGRICULTURAL MANAGEMENT ON SOIL CARBON AND pH IN THE DOUGLAS DALY REGION OF THE NORTHERN TERRITORY, accessed July 16, 2025,

View Source
Preview of Crop and Pasture Science - CSIRO PUBLISHING, accessed July 10, 2025
Crop and Pasture Science - CSIRO PUBLISHING, accessed July 10, 2025
Direct Evidence 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 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
Direct Evidence Journal

Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - BioOne Complete

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 - CSIRO PUBLISHING | Crop and Pasture Science, 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 - CSIRO PUBLISHING | Crop and Pasture Science, accessed July 10, 2025
Contextual Support Journal

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

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 | Nutrient Management - Mosaic Crop Nutrition
Potassium | Nutrient Management - Mosaic Crop Nutrition
Contextual Support Journal

Potassium | Nutrient Management - Mosaic Crop Nutrition

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 Control of Plant Functions: Ecological and Agricultural Implications - PMC, accessed July 30, 2025,
Potassium Control of Plant Functions: Ecological and Agricultural Implications - PMC, accessed July 30, 2025,
Contextual Support Journal

Regenerative Agriculture - Nuffield Farming Scholarships

View Source
Preview of Potassium for crop production | UMN Extension
Potassium for crop production | UMN Extension
Contextual Support Government

Potassium for crop production | UMN Extension

View Source
Preview of Potassium In Soil Explained - Soil Quality Knowledge Base
Potassium In Soil Explained - Soil Quality Knowledge Base
Contextual Support GreyLiterature

Potassium In Soil Explained - Soil Quality Knowledge Base

View Source
Preview of Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 5, 2025,
Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed August 5, 2025,
Contextual Support Journal

Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health - MDPI, accessed July 20, 2025,

View Source
Preview of Soil factors affecting the availability of potassium to plants for Western Australian soils: a glasshouse study | Request PDF - ResearchGate
Soil factors affecting the availability of potassium to plants for Western Australian soils: a glasshouse study | Request PDF - ResearchGate
Direct Evidence Journal

Soil factors affecting the availability of potassium to plants for Western Australian soils: a glasshouse study | Request PDF - ResearchGate

View Source
Preview of Soil K rundown in the Western grains region – where, why and what ...
Soil K rundown in the Western grains region – where, why and what ...
Contextual Support Journal

Soil K rundown in the Western grains region – where, why and what ...

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 Government

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

View Source

Context

  • Region Australia
  • Biome Temperate Semi-Arid Shrublands & Open Woodlands
  • Land Use Agricultural Crop Production
  • Assessment Conservation Target
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 9 Jun 2026

Notes

The benchmark is set well above critical deficiency thresholds to ensure robust ecosystem function, particularly for drought resilience and disease resistance. It is designed to build soil reserves and avoid the upper detrimental threshold where excessive potassium can cause nutrient imbalances.