Soil Potassium

AUS-TGP-CON-SOK General Moderate confidence

Benchmark Value

No specific value — see range
Range: 121 to 200 mg/kg
Thresholds: Lower: 80, Upper: 200
Optimal Range: 121 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 final benchmark and its functional context are summarized in the table below.

Metric Definition:

Available soil potassium (K) measured by the Colwell K soil test, representing the ecologically optimal range for high-integrity conservation areas.

Benchmark Definition:

This benchmark defines the ecologically optimal range of soil potassium for high-integrity conservation areas in temperate grassy woodlands and plains with sandy loam soils, adapted from agronomic ideal targets to support native biodiversity without promoting invasive species.

Justification:

It reflects values sufficient for native biodiversity without promoting invasive species.

Sources (1)

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

Understanding soil tests for pastures

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Supporting Sources (32)

Additional references from the underlying research that informed this benchmark.

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(PDF) Determining reference conditions for management and ..., accessed August 5, 2025,
Contextual Support

(PDF) Impacts of tree invasion on floristic composition of subtropical grasslands on the Bunya Mountains, Australia - ResearchGate, accessed May 19, 2025

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Approved Conservation Advice for the White Box - Yellow Box - Blakely's Red Gum Grassy Woodland and Derived Native Grassland - DCCEEW, accessed August 12, 2025,
Contextual Support Journal

Conservation Advice for Lowland Grassy Woodland in the South East Corner Bioregion, accessed August 6, 2025

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Preview of Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Contextual Support Journal

Root Structure and Functioning for Efficient Acquisition of Phosphorus: Matching Morphological and Physiological Traits

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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

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Preview of Ecology of Australia: the effects of nutrient-poor soils and intense fires - PubMed, accessed August 11, 2025,
Ecology of Australia: the effects of nutrient-poor soils and intense fires - PubMed, accessed August 11, 2025,
Contextual Support Journal

Ecology of Australia: the effects of nutrient-poor soils and intense fires - PubMed

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Environment - Restore Trees NSW, accessed August 11, 2025,
Contextual Support Government

Environment - Restore Trees NSW, accessed August 11, 2025,

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Preview of Eucalyptus recruitment in degraded woodlands: no benefit from elevated soil fertility, accessed August 11, 2025,
Eucalyptus recruitment in degraded woodlands: no benefit from elevated soil fertility, accessed August 11, 2025,
Contextual Support

Eucalyptus recruitment in degraded woodlands: no benefit from elevated soil fertility, accessed August 11, 2025,

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Preview of Grasslands and Grassy Woodlands of the VVP: Landholders Guide - Greening Australia, accessed August 11, 2025,
Grasslands and Grassy Woodlands of the VVP: Landholders Guide - Greening Australia, accessed August 11, 2025,
Contextual Support Journal

www.greeningaustralia.org.au, accessed May 17, 2025,

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Preview of Grassy woodlands | Landscape Australia, accessed August 5, 2025,
Grassy woodlands | Landscape Australia, accessed August 5, 2025,
Contextual Support GreyLiterature

Grassy woodlands | Landscape Australia, accessed August 4, 2025,

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Preview of Grey Box (Eucalyptus microcarpa) Grassy Woodlands and Derived Native Grasslands of South-eastern Australia, accessed August 10, 2025,
Grey Box (Eucalyptus microcarpa) Grassy Woodlands and Derived Native Grasslands of South-eastern Australia, accessed August 10, 2025,
Contextual Support

Is there a close association between 'soils' and 'vegetation'? A case study from central western New South Wales, accessed August 4, 2025,

View Source
Preview of Identification Guidelines for Endangered Ecological Communities: White box - yellow box - Blakely's red gum woodland - NSW Environment Protection Authority, accessed August 11, 2025,
Identification Guidelines for Endangered Ecological Communities: White box - yellow box - Blakely's red gum woodland - NSW Environment Protection Authority, accessed August 11, 2025,
Contextual Support Journal

Identification Guidelines for Endangered Ecological Communities: White box - yellow box - Blakely's red gum woodland - NSW Environment Protection Authority, accessed August 11, 2025,

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Preview of Identifying ecological barriers to restoration in temperate grassy woodlands: soil changes associated with different degradation states - ResearchGate, accessed August 5, 2025,
Identifying ecological barriers to restoration in temperate grassy woodlands: soil changes associated with different degradation states - ResearchGate, accessed August 5, 2025,
Contextual Support Journal

(PDF) Identifying ecological barriers to restoration in temperate grassy woodlands: soil changes associated with different degradation states - ResearchGate, accessed August 4, 2025,

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Preview of Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain p - BioOne Complete, accessed August 11, 2025,
Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain p - BioOne Complete, accessed August 11, 2025,
Contextual Support Journal

Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain p - BioOne Complete, accessed August 11, 2025,

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Preview of Multiple adaptive responses of Australian native perennial legumes with pasture potential to grow in phosphorus- and moisture-limited environments, accessed August 11, 2025,
Multiple adaptive responses of Australian native perennial legumes with pasture potential to grow in phosphorus- and moisture-limited environments, accessed August 11, 2025,
Contextual Support Journal

Multiple adaptive responses of Australian native perennial legumes with pasture potential to grow in phosphorus- and moisture-limited environments, accessed July 16, 2025,

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Preview of National Soil Action Plan - DAFF, accessed August 11, 2025,
National Soil Action Plan - DAFF, accessed August 11, 2025,
Contextual Support Journal

National Soil Action Plan - DAFF, accessed August 11, 2025,

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Preview of Natural Temperate Grassland of the Southern Tablelands of NSW and the Australian Capital Territory. - DCCEEW, accessed August 12, 2025,
Natural Temperate Grassland of the Southern Tablelands of NSW and the Australian Capital Territory. - DCCEEW, accessed August 12, 2025,
Contextual Support Government

The Impact of Tree Species on Microbial Community Structure and Soil Function on Forest Plantations in the Central Hardwoods Reg, accessed August 10, 2025,

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Preview of NVIS Fact sheet MVG 19 	6 Tussock grasslands, accessed July 16, 2025,
NVIS Fact sheet MVG 19 6 Tussock grasslands, accessed July 16, 2025,
Contextual Support Journal

Understanding soil pH, accessed August 28, 2025,

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Preview of Overcoming restoration thresholds and increasing revegetation success for a range of canopy species in a degraded urban Mediterranean-type woodland ecosystem - CSIRO PUBLISHING | Australian Journal of Botany, accessed August 11, 2025,
Overcoming restoration thresholds and increasing revegetation success for a range of canopy species in a degraded urban Mediterranean-type woodland ecosystem - CSIRO PUBLISHING | Australian Journal of Botany, accessed August 11, 2025,
Contextual Support Journal

Overcoming restoration thresholds and increasing revegetation success for a range of canopy species in a degraded urban Mediterranean-type woodland ecosystem - CSIRO PUBLISHING | Australian Journal of Botany, accessed August 11, 2025,

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Preview of Patterns in potassium dynamics in forest ecosystems - PubMed, accessed August 11, 2025,
Patterns in potassium dynamics in forest ecosystems - PubMed, accessed August 11, 2025,
Contextual Support Journal

Patterns in potassium dynamics in forest ecosystems - PubMed, accessed July 30, 2025

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

Soil fertility in grazing systems: Manage potassium to manage nitrogen - Crops and Soils, accessed July 28, 2025,

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Preview of Potassium Control of Plant Functions: Ecological and Agricultural Implications - MDPI, accessed August 11, 2025,
Potassium Control of Plant Functions: Ecological and Agricultural Implications - MDPI, accessed August 11, 2025,
Contextual Support Journal

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

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Preview of Potassium for high-performing pastures | Nutrient Advantage, accessed July 18, 2025,
Potassium for high-performing pastures | Nutrient Advantage, accessed July 18, 2025,
Contextual Support Journal

Potassium for high rainfall pastures - DPIRD's Digital library

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Preview of Potassium In Soil Explained - Soil Quality Knowledge Base, accessed August 11, 2025,
Potassium In Soil Explained - Soil Quality Knowledge Base, accessed August 11, 2025,
Contextual Support GreyLiterature

What are the optimum nutrient targets for pastures? - Soil Health Knowledgebase, accessed July 28, 2025,

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Preview of Protecting Critically Endangered Grasslands | Victorian Auditor-General's Office, accessed August 10, 2025
Protecting Critically Endangered Grasslands | Victorian Auditor-General's Office, accessed August 10, 2025
Contextual Support Government

Protecting native grasses – ANU Sustainable Farms, accessed August 11, 2025,

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Preview of Should I Fertilise Australian Native Plants? - Natural Growth Institute, accessed August 11, 2025,
Should I Fertilise Australian Native Plants? - Natural Growth Institute, accessed August 11, 2025,
Contextual Support GreyLiterature

Should I Fertilise Australian Native Plants? - Natural Growth Institute, accessed August 11, 2025,

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Preview of Soil biodiversity | Land and soil - Environment and Heritage - NSW Government, accessed August 11, 2025,
Soil biodiversity | Land and soil - Environment and Heritage - NSW Government, accessed August 11, 2025,
Contextual Support Government

Soil biodiversity | Land and soil - Environment and Heritage - NSW Government, accessed August 11, 2025,

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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,

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Preview of Soil Research - CSIRO PUBLISHING
Soil Research - CSIRO PUBLISHING
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 13, 2025

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Preview of Towards restoration of grassy White and Yellow Box woodlands ..., accessed August 11, 2025,
Towards restoration of grassy White and Yellow Box woodlands ..., accessed August 11, 2025,
Contextual Support GreyLiterature

(PDF) Soil and vegetation response to thinning White Cypress Pine ..., accessed July 19, 2025,

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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,

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Preview of White Box Yellow Box Blakely's Red Gum Woodland - Determination to make a minor amendment to Part 3 of Schedule 1 of the Threatened Species Conservation Act - Environment and Heritage, accessed August 11, 2025,
White Box Yellow Box Blakely's Red Gum Woodland - Determination to make a minor amendment to Part 3 of Schedule 1 of the Threatened Species Conservation Act - Environment and Heritage, accessed August 11, 2025,
Contextual Support Regulatory Framework Government

White Box Yellow Box Blakely's Red Gum Woodland - Determination to make a minor amendment to Part 3 of Schedule 1 of the Threatened Species Conservation Act - Environment and Heritage, accessed August 11, 2025,

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Preview of Woodlands - DCCEEW, accessed August 5, 2025,
Woodlands - DCCEEW, accessed August 5, 2025,
Contextual Support

Woodlands - DCCEEW, accessed May 19, 2025

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Context

  • Region Australia
  • Biome Temperate Grassy Woodlands & Plains
  • Land Use Conservation / Protected Natural Areas
  • Assessment Conservation Target
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 15 Mar 2026

Notes

Lower Critical Threshold: <80 mg/kg for sandy loams; Upper Detrimental Threshold: >200 mg/kg (sandy loams) is associated with nutrient imbalances and the promotion of exotic annuals, indicating a degraded state.