Soil Nitrogen

AUS-ASC-LVG-SON General Moderate confidence

Benchmark Value

1000 mg/kg
Thresholds: Lower: 1000, Upper: —
Direction: Higher is desirable ↑
Form: LowerThreshold

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 13 benchmarks together — the OptimalRange form drives the primary score, while 12 guard(s) constrain the result.

Evidence & Context

A functional threshold can be inferred. Given that the natural range for Total N in healthy sites starts at approximately 3,000 mg/kg, any site with a Total N value falling significantly below this level (e.g., <1,000 mg/kg) would indicate catastrophic loss of the soil's organic capital and a severely compromised ecosystem.

Metric Definition:

Total Soil Nitrogen concentration indicating severe degradation when below this threshold.

Benchmark Definition:

A lower critical threshold for Total Soil Nitrogen below which severe ecosystem degradation is indicated.

Justification:

A significant drop from the benchmark range (e.g., below 1,000-3,000 mg/kg) would indicate severe degradation via topsoil loss.

Sources (1)

Preview of Australian dryland soils are acidic and nutrient‐depleted, and have unique microbial communities compared with other drylands - Arid Ecology Lab, accessed August 3, 2025
Australian dryland soils are acidic and nutrient‐depleted, and have unique microbial communities compared with other drylands - Arid Ecology Lab, accessed August 3, 2025 Government

Beringer, J., et al. 2022. Carbon and water fluxes over a temperate Eucalyptus forest and a tropical wet/dry savanna in Australia. Agricultural and Forest Meteorology 129(3):151-173.

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Preview of Impact of atmospheric Nitrogen deposition on upland and alpine ecosystems
Impact of atmospheric Nitrogen deposition on upland and alpine ecosystems
Contextual Support Journal

Impact of atmospheric Nitrogen deposition on upland and alpine ecosystems

View Source
Preview of Patterns of variation in Australian alpine soils and their relationships to parent material, vegetation formation, climate and topography | Request PDF - ResearchGate, accessed August 3, 2025,
Patterns of variation in Australian alpine soils and their relationships to parent material, vegetation formation, climate and topography | Request PDF - ResearchGate, accessed August 3, 2025,
Direct Evidence Journal

Patterns of variation in Australian alpine soils and their relationships to parent material, vegetation formation, climate and topography | Request PDF - ResearchGate

View Source
Preview of STATEMENTS OF UNACCEPTABILITY OF GRAZING IN THE AUSTRALIAN ALPS
STATEMENTS OF UNACCEPTABILITY OF GRAZING IN THE AUSTRALIAN ALPS
Contextual Support

STATEMENTS OF UNACCEPTABILITY OF GRAZING IN THE AUSTRALIAN ALPS

View Source

Context

  • Region Australia
  • Biome Alpine and Subalpine Complex
  • Land Use Livestock Grazing & Pasture
  • Assessment Pristine Reference
  • Evidence Type DegradationThreshold

Lifecycle

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

Notes

No direct measurement for a Total N critical threshold is available; this is an inferred functional threshold.