Soil pH

AUS-TMI-LVG-SPH General Low confidence

Benchmark Value

7 pH (CaCl₂)
Direction: Higher is desirable ↑
Form: MaximumOnly

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 19 benchmarks together — the OptimalRange form drives the primary score, while 18 guard(s) constrain the result.

Evidence & Context

Upper Detrimental Threshold: Detrimental effects begin to appear above pH(CaCl₂) ~7.0, with significant issues emerging above pH 7.5.

Metric Definition:

Soil pH measured in calcium chloride solution (pH(CaCl₂)) representing the upper detrimental threshold above which ecological imbalances and micronutrient deficiencies occur.

Benchmark Definition:

The pH(CaCl₂) level above which micronutrient deficiencies and ecological imbalances begin to occur in the Tropical & Subtropical Maritime Islands biome.

Justification:

Evidence indicates that pH above 7.0 leads to micronutrient deficiencies and ecological imbalance in naturally acidic soils.

Sources (1)

Preview of AGRICULTURAL AUDIT & LAND USE CAPABILITY ASSESSMENT ..., accessed July 30, 2025,
AGRICULTURAL AUDIT & LAND USE CAPABILITY ASSESSMENT ..., accessed July 30, 2025, Journal

VEGETATION 0}' LORD HOWE ISLAND - Botanic Gardens of Sydney

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Livestock Grazing & Pasture
  • Assessment Not Stated
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 10 Jun 2026

Notes

Significant issues emerge above pH 7.5 including micronutrient deficiencies and soil structure problems. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.