Soil Nitrogen

AUS-TSR-CON-SON General Moderate confidence

Benchmark Value

No specific value — see range

Range: 5000 to 1E+04 mg/kg

Optimal Range: 5000 to 1E+04

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 2 benchmarks together — the OptimalRange form drives the primary score, while 1 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary Point Guard

Evidence & Context

Optimal Range: Characterized by a combination of high Total Nitrogen (e.g., 5,000–10,000 mg/kg on ferrosols), a low soil C:N ratio (<20) indicating efficient cycling, and negligible leachable nitrate (NO₃⁻) indicating high retention integrity.

Metric Definition:

Functional range of Total Soil Nitrogen concentration indicating optimal ecosystem function.

Benchmark Definition:

This benchmark defines the optimal functional range of Total Soil Nitrogen concentration in ferrosol soils of subtropical rainforests, supporting efficient nutrient cycling and retention.

Justification:

Based on evidence that this range supports high biological efficiency and nutrient retention in ferrosol soils of tropical rainforests.

Sources (1)

Remnant riparian rainforest restoration: Soil property and functional recovery in subtropical Australia.

Remnant riparian rainforest restoration: Soil property and functional recovery in subtropical Australia.

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Supporting Sources (6)

Additional references from the underlying research that informed this benchmark.

A conceptual model of nitrogen dynamics for the Great Barrier Reef catchments - Griffith Research Online, accessed July 22, 2025,

Contextual Support Journal

A conceptual model of nitrogen dynamics for the Great Barrier Reef catchments - Griffith Research Online

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Preview of Early response of soil properties and function to riparian rainforest restoration - Lake Baroon Catchment Care Group, accessed July 18, 2025,

Early response of soil properties and function to riparian rainforest restoration - Lake Baroon Catchment Care Group, accessed July 18, 2025,

Contextual Support Journal

Ecology of Nitrogen Fixing, Nitrifying, and Denitrifying ...

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Effects of long-term nitrogen and phosphorus additions on soil acidification in an N-rich tropical forest | Request PDF - ResearchGate

Contextual Support Journal

Report: Management of the Great Barrier Reef - Parliament of Australia

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Maycock, Colin Rulzion (1998) Plant-soil nutrient relationships in ...

Contextual Support Journal

Maycock, Colin Rulzion (1998) Plant-soil nutrient relationships in ...

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Nutrient limitation of soil microbial processes in tropical forests - ResearchGate

Contextual Support

Nutrient limitation of soil microbial processes in tropical forests - ResearchGate

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Review of C:N Ratios in Vegetation, Litter and Soil Under Australian Native Forests and Plantations - DCCEEW

Contextual Support Journal

Review of C:N Ratios in Vegetation, Litter and Soil ... - DCCEEW

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Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Conservation / Protected Natural Areas
Assessment Pristine Reference
Vegetation Forest
Evidence Type HealthyOperationalRange

Lifecycle

Status Active
Version 1
Effective From 24 Mar 2026

Notes

No upper detrimental threshold — higher values are always better up to natural saturation. Optimal state also requires low C:N ratio (<20) and negligible leachable nitrate; high Total Nitrogen alone is not sufficient.

Related Benchmarks

Other benchmarks in the AUS-TSR-CON-SON family.