Soil Potassium

Benchmark Value

250 mg/kg

Thresholds: Lower: —, Upper: 250

Direction: Higher is desirable ↑

Form: UpperThreshold

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 3 benchmarks together — the OptimalRange form drives the primary score, while 2 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary LowerThreshold Guard UpperThreshold Guard

Evidence & Context

Sustained Colwell K levels falling into the "High" agronomic ranges (e.g., for Clay Loams: >250-300 mg/kg) should trigger investigation for potential nutrient imbalances.

Metric Definition:

Colwell K soil potassium concentration in mg/kg

Benchmark Definition:

This benchmark represents the upper detrimental threshold of soil potassium concentration above which nutrient imbalances and ecosystem harm may occur in clay loam soils under grazing in temperate dry woodlands and native grasslands in Australia.

Justification:

High potassium levels can induce magnesium and calcium deficiencies, leading to animal health issues and ecosystem imbalance.