Soil Nitrogen — Benchmark Detail

Benchmark Value

400 mg/kg

Direction: Higher is desirable ↑

Form: MinimumOnly

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

Contributing Benchmarks

OptimalRange Primary MinimumOnly Guard MaximumOnly Guard

Evidence & Context

A drop to a level below 400 mg/kg could be considered a critical point.

Metric Definition:

Critical lower threshold of total soil nitrogen indicating nutrient depletion

Benchmark Definition:

Critical lower threshold of total soil nitrogen below which nutrient depletion and long-term productivity loss occur in Australian Temperate Grassy Woodlands & Plains production forestry on loamy sand soil.

Justification:

Inferred threshold based on principles of nutrient removal from harvesting and the need to maintain soil organic matter.

Sources (2)

EFFECTS OF INTENSIFIED HARVESTING ON RATES OF NITROGEN AND PHOSPHORUS REMOVAL FROM PINUS RADIATA AND EUCALYPTUS FORESTS IN AUSTR - Scion Research Journal

EFFECTS OF INTENSIFIED HARVESTING ON RATES OF NITROGEN AND PHOSPHORUS REMOVAL FROM PINUS RADIATA AND EUCALYPTUS FORESTS IN AUSTR

View Source

Soil management guides - NSW Department of Primary Industries GreyLiterature

Soil management guides - NSW Department of Primary Industries

View Source

Supporting Sources (4)

Additional references from the underlying research that informed this benchmark.

Chapter 9 AUSTRALIAN GRASSLANDS - Food and Agriculture Organization of the United Nations, accessed August 5, 2025,

Contextual Support Government

How Past Rainfall Shapes Australia's Dryland Ecosystems - Western Sydney University

View Source

Elevated carbon dioxide increases soil nitrogen and phosphorus availability in a phosphorus-limited Eucalyptus woodland

Direct Evidence Journal

Elevated carbon dioxide increases soil nitrogen and phosphorus availability in a phosphorus-limited Eucalyptus woodland

View Source

Living soils in agriculture | TERN Australia, accessed July 25, 2025,

Contextual Support Government

Living soils in agriculture | TERN Australia, accessed July 16, 2025,

View Source

Temperate Grasslands - Greening Australia, accessed August 4, 2025

Contextual Support Journal

Plant nutrients in the soil - NSW Department of Primary Industries

View Source

Context

Region Australia
Biome Temperate Grassy Woodlands & Plains
Land Use Production Forestry
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 9 Jun 2026

Notes

Represents a significant depletion of natural nitrogen capital below the reference state, risking long-term productivity loss. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

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