Soil Nitrogen

AUS-TDG-FOR-SON General Moderate confidence

Benchmark Value

5000 mg/kg
Thresholds: Lower: —, Upper: 5000
Direction: Lower is desirable ↓
Form: UpperThreshold

Scoring Curve

Scoring curve unavailable

The scoring engine could not generate a curve for this benchmark context. The primary form is CompositeFramework, but the benchmark data may be missing required fields (e.g., optimal range bounds for an OptimalRange benchmark). This is typically a data quality issue in the benchmark pipeline.

Contributing Benchmarks

CompositeFramework Primary OptimalRange Guard LowerThreshold Guard UpperThreshold Guard Point Guard MinimumOnly Guard OptimalRange Guard MaximumOnly Guard Point Guard OptimalRange Guard Point Guard LowerThreshold Guard OptimalRange Guard UpperThreshold Guard Point Guard OptimalRange Guard MaximumOnly Guard Point Guard MinimumOnly Guard MaximumOnly Guard OptimalRange Guard OptimalRange Guard

Evidence & Context

A detrimental upper threshold exists at >5000 mg/kg, where excess nitrogen leads to biodiversity loss, soil acidification, and other negative ecological impacts.

Metric Definition:

Upper detrimental threshold of Total Soil Nitrogen above which negative ecological impacts occur.

Benchmark Definition:

Upper detrimental threshold of Total Soil Nitrogen above which negative ecological impacts occur in Australian Temperate Dry Woodlands & Native Grasslands under production forestry.

Justification:

Exceeding this threshold risks nitrogen saturation, leading to biodiversity loss, soil acidification, and increased greenhouse gas emissions.

Sources (1)

Preview of A review of sampling designs for the measurement of soil organic carbon in Australian grazing lands - Integrity Systems, accessed July 27, 2025,
A review of sampling designs for the measurement of soil organic carbon in Australian grazing lands - Integrity Systems, accessed July 27, 2025, Government

Total nitrogen levels as a key constraint on soil organic carbon ...

View Source

Supporting Sources (17)

Additional references from the underlying research that informed this benchmark.

Preview of Australia's forests – overview - DAFF
Australia's forests – overview - DAFF
Contextual Support

AUSTRALIA'S STATE OF THE FORESTS REPORT - DAFF, accessed August 28, 2025,

View Source
Preview of Australia's Native Vegetation Framework - DAFF, accessed August 6, 2025,
Australia's Native Vegetation Framework - DAFF, accessed August 6, 2025,
Contextual Support Journal

Soil nitrogen dynamics in natural forest ecosystem: a review - Frontiers, accessed August 28, 2025,

View Source
Preview of Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 28, 2025,
Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 28, 2025,
Contextual Support Journal

Ryan, M. H., & Kirkegaard, J. A. (2012). The agronomic relevance of arbuscular mycorrhizas in the fertility of Australian extensive cropping systems. Agriculture, Ecosystems & Environment.

View Source
Preview of Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC, accessed August 5, 2025,
Contextual Support Journal

Root Structure and Functioning for Efficient Acquisition of Phosphorus: Matching Morphological and Physiological Traits

View Source
Preview of Chapter 9 AUSTRALIAN GRASSLANDS - Food and Agriculture Organization of the United Nations, accessed August 5, 2025,
Chapter 9 AUSTRALIAN GRASSLANDS - Food and Agriculture Organization of the United Nations, accessed August 5, 2025,
Contextual Support Government

Karst and agriculture in Australia - Digital Commons @ USF, accessed July 26, 2025,

View Source
Preview of Coarse woody debris reduces the rate of moisture loss from surface soils of cleared temperate Australian woodlands - CSIRO Publishing
Coarse woody debris reduces the rate of moisture loss from surface soils of cleared temperate Australian woodlands - CSIRO Publishing
Contextual Support Journal

Coarse woody debris reduces the rate of moisture loss from surface soils of cleared temperate Australian woodlands - CSIRO PUBLISHING | Soil Research, accessed August 28, 2025,

View Source
Preview of Determining baselines, drivers and trends of soil health and stability in New South Wales forests., accessed August 28, 2025,
Determining baselines, drivers and trends of soil health and stability in New South Wales forests., accessed August 28, 2025,
Direct Evidence Journal

Addressing the rundown of nitrogen and soil organic carbon - GRDC, accessed August 28, 2025,

View Source
Preview of Does diversity influence soil nitrate, light availability and productivity in the establishment phase of Australian temperate grassland reconstruction? - PubMed Central, accessed August 28, 2025,
Does diversity influence soil nitrate, light availability and productivity in the establishment phase of Australian temperate grassland reconstruction? - PubMed Central, accessed August 28, 2025,
Contextual Support

Does diversity influence soil nitrate, light availability and productivity in the establishment phase of Australian temperate grassland reconstruction? - PubMed Central, accessed August 28, 2025,

View Source
Preview of Grassed up - Introduction - NSW Department of Primary Industries, accessed August 5, 2025,
Grassed up - Introduction - NSW Department of Primary Industries, accessed August 5, 2025,
Contextual Support

Why phosphorus is important - NSW Department of Primary Industries, accessed July 18, 2025,

View Source
Preview of Long term accumulation of N in soils of dry mixed eucalypt forest in ..., accessed August 28, 2025,
Long term accumulation of N in soils of dry mixed eucalypt forest in ..., accessed August 28, 2025,
Contextual Support Journal

Increasing and declining native species in urban remnant grasslands respond differently to nitrogen addition and disturbance - PMC, accessed August 28, 2025,

View Source
Preview of Nitrogen Saturation in Temperate Forest Ecosystems, accessed August 28, 2025,
Nitrogen Saturation in Temperate Forest Ecosystems, accessed August 28, 2025,
Contextual Support Journal

Nitrogen Saturation in Temperate Forest Ecosystems, accessed August 28, 2025,

View Source
Preview of Refining benchmarks for soil organic carbon in Australia's temperate forests - ResearchGate, accessed August 28, 2025,
Refining benchmarks for soil organic carbon in Australia's temperate forests - ResearchGate, accessed August 28, 2025,
Contextual Support Journal

Mapping soil organic carbon fractions for Australia, their stocks, and uncertainty - BG, accessed March 28, 2026,

View Source
Preview of Soil nitrogen dynamics in natural forest ecosystem: a review - ResearchGate, accessed August 28, 2025,
Soil nitrogen dynamics in natural forest ecosystem: a review - ResearchGate, accessed August 28, 2025,
Contextual Support

Soil nitrogen dynamics in natural forest ecosystem: a review - ResearchGate, accessed August 28, 2025,

View Source
Preview of Soil Nitrogen Supply | Fact Sheets | soilquality.org.au, accessed July 25, 2025,
Soil Nitrogen Supply | Fact Sheets | soilquality.org.au, accessed July 25, 2025,
Contextual Support Government

Soil Nitrogen Supply | Fact Sheets | soilquality.org.au, accessed May 11, 2025,

View Source
Preview of The changing the availability of nutrients in global grasslands | TERN Australia, accessed August 11, 2025
The changing the availability of nutrients in global grasslands | TERN Australia, accessed August 11, 2025
Direct Evidence Government

The changing the availability of nutrients in global grasslands ..., accessed August 28, 2025,

View Source
Preview of The combined effect of fire and nitrogen addition on biodiversity and herbaceous aboveground productivity in a coastal shrubland - PMC, accessed August 28, 2025,
The combined effect of fire and nitrogen addition on biodiversity and herbaceous aboveground productivity in a coastal shrubland - PMC, accessed August 28, 2025,
Contextual Support Journal

Measuring plant-associated nitrogen fixation in agricultural systems, accessed August 4, 2025,

View Source
Preview of Understanding soil tests for pastures | Soil | Farm management ..., accessed May 12, 2025
Understanding soil tests for pastures | Soil | Farm management ..., accessed May 12, 2025
Contextual Support Government

Understanding soil tests for pastures

View Source

Context

  • Region Australia
  • Biome Temperate Dry Woodlands & Native Grasslands
  • Land Use Production Forestry
  • Assessment Pristine Reference
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 24 Mar 2026

Notes

This threshold marks the point where nitrogen acts as a pollutant rather than a nutrient.

Related Benchmarks

Other benchmarks in the AUS-TDG-FOR-SON family.

3330 mg/kg Moderate
Production Forestry · Pristine Reference
Point Active v1
1000 mg/kg Moderate
Production Forestry · Pristine Reference
LowerThreshold Active v1
— mg/kg Moderate
Production Forestry · Pristine Reference
OptimalRange Active v1