Soil Potassium

AUS-TMS-FOR-SOK General Low confidence

Benchmark Value

No specific value — see range

Range: 60 to 100 mg/kg

Optimal Range: 60 to 100

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

a tentative reference range for available soil potassium (e.g., Colwell K or equivalent, measured in the 0-10 cm or 0-15 cm depth) on Kandosols and similar sandy or loamy savanna soils is proposed as 60 to 100 mg/kg.

Metric Definition:

available soil potassium (e.g., Colwell K or equivalent extraction method, measured in the 0-10 cm or 0-15 cm soil depth)

Benchmark Definition:

This benchmark represents the available soil potassium range considered optimal for ecological health and sustainable production forestry in Tropical Monsoonal Savannas on Kandosols and similar sandy or loamy savanna soils.

Justification:

Positioned above native deficiency levels and agronomic critical thresholds, while avoiding excessive fertilization and cation imbalances.

Sources (2)

Soil Research - CSIRO PUBLISHING Journal

Soil Research - CSIRO PUBLISHING

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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

Agriculture Victoria. (2025). Understanding soil tests for pastures. Farm Management.

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Supporting Sources (6)

Additional references from the underlying research that informed this benchmark.

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,

Direct Evidence Journal

Nutrient Cycling in Australian Savannas on JSTOR - DOI

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Preview of Leaf-level photosynthetic capacity dynamics in relation to soil and foliar nutrients along forest–savanna boundaries in Ghana and Brazil | Tree Physiology | Oxford Academic

Leaf-level photosynthetic capacity dynamics in relation to soil and foliar nutrients along forest–savanna boundaries in Ghana and Brazil | Tree Physiology | Oxford Academic

Contextual Support Journal

Leaf-level photosynthetic capacity dynamics in relation to soil and foliar nutrients along forest–savanna boundaries in Ghana and Brazil | Tree Physiology | Oxford Academic

View Source

Preview of Multiple soil element and pH interactions constrain plant performance on tropical soils with a long history of fire - CSIRO PUBLISHING | Soil Research, accessed May 16, 2025,

Multiple soil element and pH interactions constrain plant performance on tropical soils with a long history of fire - CSIRO PUBLISHING | Soil Research, accessed May 16, 2025,

Direct Evidence Journal

Soil Research - CSIRO PUBLISHING

View Source