Soil Organic Carbon (SOC)

AUS-TGP-AGR-SOC General Moderate confidence

Benchmark Value

No specific value — see range
Thresholds: Lower: 1.5, 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.

Evidence & Context

A pivotal study identified a critical initial SOC threshold of approximately 1.5% that fundamentally alters how the soil carbon system responds to management inputs, specifically nitrogen fertilization.

Metric Definition:

Critical SOC threshold affecting soil carbon stability and response to nitrogen fertilization

Benchmark Definition:

Critical SOC threshold for stable carbon accumulation and effective nitrogen response.

Justification:

Represents a biogeochemical tipping point where soil carbon cycling shifts from transient to stable pools.

Sources (1)

Preview of Soil organic carbon thresholds control fertilizer effects on carbon accrual in croplands worldwide - PMC
Soil organic carbon thresholds control fertilizer effects on carbon accrual in croplands worldwide - PMC Journal

Soil organic carbon thresholds control fertilizer effects on carbon accrual in croplands worldwide - PMC

View Source

Supporting Sources (4)

Additional references from the underlying research that informed this benchmark.

Preview of Beefing up carbon capture | On-farm emissions case studies - Agriculture Victoria
Beefing up carbon capture | On-farm emissions case studies - Agriculture Victoria
Contextual Support Government

Beefing up carbon capture | On-farm emissions case studies - Agriculture Victoria

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Preview of Development of a soil carbon benchmark matrix for central west NSW - IUSS
Development of a soil carbon benchmark matrix for central west NSW - IUSS
Direct Evidence Journal

Development of a soil carbon benchmark matrix for central west NSW - IUSS

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Preview of How Much Carbon Can Soil Store - NSW | Fact Sheets | soilquality ...
How Much Carbon Can Soil Store - NSW | Fact Sheets | soilquality ...
Direct Evidence Government

How Much Carbon Can Soil Store - NSW | Fact Sheets | soilquality.org.au

View Source
Preview of Soil carbon dynamics under different cropping and pasture management in temperate Australia: Results of three long-term experiments - CSIRO Publishing
Soil carbon dynamics under different cropping and pasture management in temperate Australia: Results of three long-term experiments - CSIRO Publishing
Contextual Support Journal

Soil carbon dynamics under different cropping and pasture management in temperate Australia: Results of three long-term experiments - CSIRO Publishing

View Source

Context

  • Region Australia
  • Biome Temperate Grassy Woodlands & Plains
  • Land Use Agricultural Crop Production
  • Assessment Degradation Threshold
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 2
  • Effective From 21 Mar 2026

Notes

Maintaining SOC above this threshold is essential for long-term ecological restoration and carbon sequestration.