Soil pH

AUS-TMS-AGR-SPH General Moderate confidence

Benchmark Value

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

Evidence & Context

While an upper detrimental threshold for ecological health due to over-management (e.g., over-liming) could be considered if pH (CaCl₂) consistently exceeds approximately 7.0 to 7.2, this is not the primary management concern.

Metric Definition:

Upper detrimental soil pH threshold measured in 0.01M CaCl₂ above which ecological health may be compromised due to micronutrient deficiencies.

Justification:

Based on general soil science principles and limited direct evidence in the target biome.

Sources (1)

Preview of Effects of agricultural management on soil carbon and pH in the Douglas Daly region of the Northern Territory - NT (Book), accessed on June 7, 2025
Effects of agricultural management on soil carbon and pH in the Douglas Daly region of the Northern Territory - NT (Book), accessed on June 7, 2025 Journal

General soil science literature and expert synthesis

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Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

Preview of Cotton Production and Sustainability in the Northern Territory: A Comprehensive Analysis of Yield, Soil Properties, and Cover Crops (Mwando et al., 2024, In: Proceedings of the 21st Australian Agronomy Conference)
Cotton Production and Sustainability in the Northern Territory: A Comprehensive Analysis of Yield, Soil Properties, and Cover Crops (Mwando et al., 2024, In: Proceedings of the 21st Australian Agronomy Conference)
Direct Evidence Journal

Cotton Production and Sustainability in the Northern Territory: A Comprehensive Analysis of Yield, Soil Properties, and Cover Crops (Mwando et al., 2024, In: Proceedings of the 21st Australian Agronomy Conference)

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Context

  • Region Australia
  • Biome Tropical Monsoonal Savannas
  • Land Use Agricultural Crop Production
  • Assessment Agricultural Biodiversity Target
  • Evidence Type DegradationThreshold

Lifecycle

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

Notes

Upper pH threshold is less critical than acidification but important to avoid micronutrient deficiencies and negative impacts on soil biology.