Soil Potassium

AUS-TSW-FOR-SOK General Moderate confidence

Benchmark Value

50 mg/kg

Direction: Higher is desirable ↑

Form: MinimumOnly

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 10 benchmarks together — the OptimalRange form drives the primary score, while 9 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary OptimalRange Guard Point Guard MaximumOnly Guard UpperThreshold Guard OptimalRange Guard LowerThreshold Guard Point Guard MinimumOnly Guard OptimalRange Guard

Evidence & Context

A soil potassium level falling below 50 mg/kg would signify a severely degraded state.

Metric Definition:

Exchangeable potassium in soil measured as mg/kg, representing plant-available potassium.

Benchmark Definition:

This benchmark defines the lower critical threshold for exchangeable soil potassium below which ecosystem function and resilience are significantly compromised in production forestry within the temperate semi-arid shrublands and open woodlands biome.

Justification:

Based on evidence from agricultural and forestry studies indicating deficiency and stress below this level.

Sources (1)

Agronomic studies in Australia for grain crops and general soil fertility guides for NSW and WA GreyLiterature

Agronomic studies in Australia for grain crops and general soil fertility guides for NSW and WA

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Preview of Does rapid utilization of elevated nutrient availability allow eucalypts to dominate in the tropical savannas of Australia? - PubMed Central, accessed May 11, 2025,

Does rapid utilization of elevated nutrient availability allow eucalypts to dominate in the tropical savannas of Australia? - PubMed Central, accessed May 11, 2025,

Contextual Support Journal

General soil fertility guides and commercial forestry studies

View Source

Soil | Australia state of the environment 2021, accessed August 12, 2025,

Direct Evidence Journal

OzFlux-TERN GWW SuperSite presentation: Soil Chemical Properties

View Source

Context

Region Australia
Biome Temperate Semi-Arid Shrublands & Open Woodlands
Land Use Production Forestry
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 25 Mar 2026

Notes

This threshold is critical for maintaining ecosystem resilience and function.

Related Benchmarks

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