Soil pH — Benchmark Detail

Benchmark Value

No specific value — see range

Range: 7 to 7.5 pH

Optimal Range: 7 to 7.5

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. The scoring engine uses 16 benchmarks together — the OptimalRange form drives the primary score, while 15 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

A potential upper detrimental limit is proposed at around pH 7.0 to 7.5 (1:5 soil:water).

Metric Definition:

Soil pH measured as a 1:5 soil:water suspension

Benchmark Definition:

This benchmark identifies a potential upper detrimental soil pH limit for Australian alpine and subalpine production forestry, beyond which negative impacts on native flora and soil microbes may occur.

Justification:

Above this pH range, micronutrient deficiencies and adverse impacts on acidophilic native flora and microbial communities may occur.

Sources (1)

Preview of (PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025,

(PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025, Journal

Soil pH | Environment, land and water - Queensland Government, accessed August 28, 2025,

View Source

Context

Region Australia
Biome Alpine and Subalpine Complex
Land Use Production Forestry
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 3
Effective From 24 Mar 2026

Notes

This upper limit is unlikely in most natural settings but relevant if management practices substantially increase soil pH.

Related Benchmarks

Other benchmarks in the AUS-ASC-FOR-SPH family.