Soil Potassium

AUS-TMI-FOR-SOK General Moderate confidence

Benchmark Value

No specific value — see range

Range: 100 to 150 mg/kg

Optimal Range: 100 to 150

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 study identifies this optimal range as being between 100.0 and 150.35 mg/dm³.

Metric Definition:

Exchangeable potassium (K+) in soil necessary to sustain high-productivity Eucalyptus forestry

Benchmark Definition:

Optimal range of exchangeable potassium in soil for high productivity in Eucalyptus plantations in the Tropical & Subtropical Maritime Islands biome under Production Forestry land use.

Justification:

This benchmark is a well-justified proxy derived from a study on high-productivity Eucalyptus plantations, a genus relevant to forestry in this biome.

Sources (3)

Establishment of critical nutrient levels in soil and plant for eucalyptus - Semantic Scholar, accessed July 30, 2025, Journal

Establishment of critical nutrient levels in soil and plant for eucalyptus - Semantic Scholar, accessed July 30, 2025

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, Journal

Regenerative Agriculture - Nuffield Farming Scholarships

View Source

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

Understanding soil tests for pastures

View Source

Supporting Sources (37)

Additional references from the underlying research that informed this benchmark.

Australian climate zones - | YourHome, accessed July 13, 2025

Contextual Support Government

Australian climate zones - | YourHome, accessed July 13, 2025,

View Source

Christmas and Cocos Islands tropical forests - Wikipedia, accessed July 30, 2025,

Contextual Support GreyLiterature

Christmas and Cocos Islands tropical forests - Wikipedia, accessed July 30, 2025,

View Source

Christmas Island National Park - Wikipedia, accessed July 30, 2025,

Contextual Support GreyLiterature

Cocos Island - Wikipedia, accessed August 2, 2025

View Source

Climate & Seasons | Australian Wildlife Journeys, accessed July 30, 2025,

Contextual Support

Soil erosion as a resilience drain in disturbed tropical forests, accessed August 1, 2025,

View Source

Cocos (Keeling) Islands - 2022 World Factbook Archive - CIA, accessed July 30, 2025,

Contextual Support Irrelevant Government

Cocos (Keeling) Islands - 2022 World Factbook Archive - CIA, accessed July 30, 2025

View Source

Conservation | Norfolk Island National Park | Parks Australia, accessed August 3, 2025,

Contextual Support Government

Conservation | Norfolk Island National Park | Parks Australia, accessed August 3, 2025,

View Source

Deforestation - Norfolk Island Flora & Fauna Society, accessed July 30, 2025,

Contextual Support GreyLiterature

Deforestation - Norfolk Island Flora & Fauna Society, accessed July 30, 2025

View Source

Fact sheets: Norfolk Island plant communities - Invasive Species Council, accessed July 30, 2025,

Contextual Support GreyLiterature

Fact sheets: Norfolk Island plant communities - Invasive Species Council, accessed July 30, 2025

View Source

Flora of the Cocos (Keeling) Islands - Wikipedia, accessed July 30, 2025, )_Islands

Contextual Support

Flora of the Cocos (Keeling) Islands - Wikipedia, accessed July 30, 2025, )_Islands

View Source

History & culture | Pulu Keeling National Park | Parks Australia, accessed July 30, 2025,

Contextual Support Government

History & culture | Pulu Keeling National Park | Parks Australia, accessed July 30, 2025

View Source

How does the nutrient cycle work in a tropical rainforest? - Quora, accessed July 30, 2025,

Contextual Support GreyLiterature

How does the nutrient cycle work in a tropical rainforest? - Quora, accessed July 30, 2025

View Source

Incredible Great Barrier Reef Islands For Your Holiday - Visitor's Guide - Queensland, accessed July 30, 2025,

Contextual Support

Incredible Great Barrier Reef Islands For Your Holiday - Visitor's Guide - Queensland, accessed August 2, 2025,

View Source

Inquiry into forestry and mining operations on the Tiwi Islands, accessed July 30, 2025,

Contextual Support Journal

Inquiry into forestry and mining operations on the Tiwi Islands, accessed July 30, 2025

View Source

List of islands of Australia - Wikipedia, accessed July 30, 2025,

Contextual Support GreyLiterature

List of islands of Australia - Wikipedia, accessed July 30, 2025

View Source

Lord Howe Island - Wikipedia, accessed July 30, 2025,

Contextual Support GreyLiterature

Lord Howe Island - Wikipedia, accessed August 1, 2025,

View Source

Lord Howe Island subtropical forests | EBSCO Research Starters, accessed August 3, 2025,

Contextual Support

Vegetation Rehabilitation Plan - Adopted March 2003.pdf - Lord Howe Island Board, accessed August 3, 2025

View Source

Lord Howe Island Subtropical Forests | One Earth, accessed July 30, 2025,

Contextual Support

Safeguarding Lord Howe Island World Heritage Area - Local Land Services, accessed August 1, 2025,

View Source

Mangroves and Wetlands | TSRA State of the Environment, accessed August 4, 2025,

Contextual Support Government

Mangroves and Wetlands | TSRA State of the Environment, accessed August 4, 2025,

View Source

Norfolk Island - Wikipedia, accessed July 30, 2025,

Contextual Support

Norfolk Island Water Resource Assessment, accessed July 30, 2025,

View Source

Norfolk Island National Park | Parks Australia, accessed July 30, 2025,

Contextual Support Government

Norfolk Island National Park | Parks Australia, accessed July 30, 2025

View Source

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

View Source

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

Plants | Christmas Island National Park | Parks Australia, accessed July 30, 2025,

Contextual Support Government

Plants | Christmas Island National Park | Parks Australia, accessed July 30, 2025

View Source

Plants | Pulu Keeling National Park | Parks Australia, accessed July 30, 2025,

Contextual Support Government

Plants | Pulu Keeling National Park | Parks Australia, accessed July 30, 2025

View Source

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,

View Source

Preview of POTASSIUM AND MAGNESIUM IN LEAF AND TOP SOIL AFFECTED BY TRIPLE SUPERPHOSPHATE FERTILISATION IN AN ACACIA MANGIUM PLANTATION - JOURNAL OF TROPICAL FOREST SCIENCE, accessed July 30, 2025,

POTASSIUM AND MAGNESIUM IN LEAF AND TOP SOIL AFFECTED BY TRIPLE SUPERPHOSPHATE FERTILISATION IN AN ACACIA MANGIUM PLANTATION - JOURNAL OF TROPICAL FOREST SCIENCE, accessed July 30, 2025,

Contextual Support Journal

POTASSIUM AND MAGNESIUM IN LEAF AND TOP SOIL AFFECTED BY TRIPLE SUPERPHOSPHATE FERTILISATION IN AN ACACIA MANGIUM PLANTATION - JOURNAL OF TROPICAL FOREST SCIENCE, accessed July 30, 2025

View Source

Research and development investment delivering for Tiwi community, accessed July 30, 2025,

Contextual Support GreyLiterature

Tiwi Islands Fire and Weed Management Plan 2021

View Source

Territory Stories - Land Capability Study of the Tiwi Islands, accessed July 30, 2025,

Contextual Support GreyLiterature

Territory Stories - Land Capability Study of the Tiwi Islands, accessed July 30, 2025

View Source

Preview of The intact and the imperilled: contrasting mammal population trajectories between two large adjacent islands - CSIRO Publishing, accessed July 30, 2025,

The intact and the imperilled: contrasting mammal population trajectories between two large adjacent islands - CSIRO Publishing, accessed July 30, 2025,

Contextual Support Journal

The intact and the imperilled: contrasting mammal population trajectories between two large adjacent islands - CSIRO Publishing, accessed July 30, 2025

View Source

The most beautiful Australian islands - Tourism Australia, accessed August 2, 2025,

Contextual Support

Lord Howe Island Subtropical Forests | One Earth

View Source

The nutrient cycle in the rainforest - Internet Geography, accessed July 30, 2025,

Contextual Support GreyLiterature

(PDF) Litterfall and the Standing Crop of Litter in Three Tropical ...

View Source

These 21 Beautiful Tropical Islands Are Closer Than You Think | Travel Insider - Qantas, accessed August 3, 2025

Contextual Support

These 21 Beautiful Tropical Islands Are Closer Than You Think | Travel Insider - Qantas, accessed July 30, 2025

View Source

Torres Strait Protected Zone Joint Authority - Australian Government Directory, accessed July 30, 2025,

Contextual Support Government

Torres Strait Protected Zone Joint Authority - Australian Government Directory, accessed July 30, 2025

View Source

Tropical Rainforest (1993), accessed July 30, 2025,

Contextual Support Journal

Tropical Rainforest (1993), accessed July 31, 2025,

View Source

Understanding nutrients in tropical rainforests - British Geological Survey, accessed July 30, 2025,

Contextual Support Government

Understanding nutrients in tropical rainforests - British Geological Survey, accessed July 30, 2025

View Source

Wet Tropics of Queensland - UNESCO World Heritage Centre, accessed July 22, 2025,

Contextual Support GreyLiterature

Wet Tropics of Queensland - UNESCO World Heritage Centre, accessed July 23, 2025

View Source

WET TROPICS OF QUEENSLAND - World Heritage Datasheet - UNEP-WCMC, accessed July 30, 2025,

Contextual Support Government

WET TROPICS OF QUEENSLAND - World Heritage Datasheet - UNEP-WCMC, accessed July 22, 2025,

View Source

Context

Region Australia
Biome Tropical & Subtropical Maritime Islands
Land Use Production Forestry
Assessment Target Condition
Evidence Type TargetCondition

Lifecycle

Status Active
Version 1
Effective From 15 Mar 2026

Notes

Lower Critical Threshold: < 50 mg/kg, below which forest health and long-term productivity are likely compromised. No upper detrimental threshold — higher values are always better up to natural saturation. Levels significantly above the optimal range (e.g., >250 mg/kg) indicate an artificial, over-fertilized state that may risk nutrient imbalances. [Migration] Original wider evidence range: 100 – 150.35 (retained OptimalRange: 100 – 150)

Related Benchmarks

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