Soil Organic Carbon (SOC)

AUS-TSR-AGR-SOC General Moderate confidence

Benchmark Value

No specific value — see range

Range: 1.9 to 2.2 %

Optimal Range: 1.9 to 2.2

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.

Evidence & Context

The study predicted that the optimal SOC concentration for achieving the highest yields and best nitrogen use efficiency was in the range of 1.9% to 2.2%.

Metric Definition:

Optimal functional range of Soil Organic Carbon (SOC) for peak crop productivity and nutrient use efficiency

Benchmark Definition:

Range representing peak ecosystem health and sustainable productivity.

Justification:

Data-driven estimate from tropical soils relevant to the Australian tropical context.

Sources (1)

$Preview of (PDF) Using active fractions of soil organic matter as indicators of ..., accessed July 19, 2025$

(PDF) Using active fractions of soil organic matter as indicators of ..., accessed July 19, 2025 GreyLiterature

Using active fractions of soil organic matter as indicators of ...

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Addressing the rundown of nitrogen and soil organic carbon - GRDC, accessed July 25, 2025,

Direct Evidence Journal

Soil | Australia state of the environment 2021

View Source

Preview of critical soil organic carbon range for optimal crop response to mineral fertiliser nitrogen on a ferralsol - ResearchGate, accessed August 3, 2025,

critical soil organic carbon range for optimal crop response to mineral fertiliser nitrogen on a ferralsol - ResearchGate, accessed August 3, 2025,

Direct Evidence

National Soil Strategy

View Source

Preview of Farming system legacy impacts on the storage and persistence of soil organic carbon and understanding the different types carbon in northern cropping systems

Farming system legacy impacts on the storage and persistence of soil organic carbon and understanding the different types carbon in northern cropping systems

Direct Evidence Journal

Farming system legacy impacts on the storage and persistence of soil organic carbon and understanding the different types carbon in northern cropping systems

View Source

Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Agricultural Crop Production
Assessment Not Stated
Evidence Type HealthyOperationalRange

Lifecycle

Status Active
Version 1
Effective From 5 Jun 2026

Notes

No upper detrimental threshold — higher values are always better up to natural saturation. This range should be interpreted as a strong, evidence-based guideline rather than an absolute value applicable to all soil types and conditions in Australia. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TSR-AGR-SOC family.