Soil Organic Carbon (SOC)

AUS-TSW-CON-SOC General Moderate confidence

Benchmark Value

No specific value — see range

Range: 1 to 1.5 %

Thresholds: Lower: 1, Upper: 1.5

Optimal Range: 1 to 1.5

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. The scoring engine uses 6 benchmarks together — the OptimalRange form drives the primary score, while 5 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary Point Guard OptimalRange Guard Point Guard LowerThreshold Guard OptimalRange Guard

Evidence & Context

A critical lower threshold is identified in the range of 1.0% to 1.5% SOC. Below this level, key ecosystem functions such as nutrient cycling, water retention, and microbial activity decline precipitously, indicating significant land degradation.

Metric Definition:

Critical lower threshold of Soil Organic Carbon concentration below which ecosystem function declines.

Benchmark Definition:

This benchmark defines the critical lower threshold of Soil Organic Carbon concentration below which key ecosystem functions decline sharply, indicating significant land degradation in temperate semi-arid shrublands and open woodlands.

Justification:

Based on literature and analogous Mediterranean ecosystem studies showing steep functional decline below this SOC range.

Sources (1)

Critical range of soil organic carbon in southern Europe lands under desertification risk - IRIS UniPA Journal

Critical range of soil organic carbon in southern Europe lands under desertification risk - IRIS UniPA

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Supporting Sources (12)

Additional references from the underlying research that informed this benchmark.

(PDF) Soil carbon sequestration in rangelands: A critical review of ...

Contextual Support Journal

Environmental drivers of soil organic carbon in the Australian rangelands - ResearchGate, accessed July 28, 2025,

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An ensemble estimate of Australian soil organic ... - EGUsphere, accessed on June 7, 2025,

Contextual Support Journal

AUSTRALIA'S STATE OF THE FORESTS REPORT - DAFF, accessed March 28, 2026,

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Preview of Baseline map of organic carbon in Australian soil to support national carbon accounting and monitoring under climate change - PubMed Central, accessed August 5, 2025,

Baseline map of organic carbon in Australian soil to support national carbon accounting and monitoring under climate change - PubMed Central, accessed August 5, 2025,

Contextual Support Journal

Baseline map of organic carbon in Australian soil to support national carbon accounting and monitoring under climate change - PMC, accessed March 28, 2026,

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Key Considerations in Sequestering Carbon as Soil Organic Carbon, accessed July 26, 2025

Contextual Support Journal

Mapping soil organic carbon fractions for Australia, their stocks, and uncertainty - BG

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Soil Carbon in South Australia: Volume 4 - Benchmarks and Data analysis for the Agricultural Zone 1990-2007

Direct Evidence Journal

Soil Carbon in South Australia: Volume 4 - Benchmarks and Data analysis for the Agricultural Zone 1990-2007

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Soil carbon monitoring and trends - Department for Environment and Water, accessed August 5, 2025,

Contextual Support Government

Common soil types | Environment, land and water - Queensland Government

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Soil Carbon Saturation: What Do We Really Know? - PMC - PubMed Central

Contextual Support

Soil Compaction of Pastures - King Conservation District, accessed July 24, 2025

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Preview of Soil carbon sequestration in rangelands a critical review of the impacts of major management strategies - CSIRO Publishing, accessed August 5, 2025,

Soil carbon sequestration in rangelands a critical review of the impacts of major management strategies - CSIRO Publishing, accessed August 5, 2025,

Contextual Support

Soil carbon sequestration in rangelands a critical review of the impacts of major management strategies - CSIRO Publishing, accessed May 13, 2025,

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Soil Carbon Sequestration Potential: A review for Australian agriculture - MLA

Contextual Support Government

Soil Carbon Sequestration Potential: A review for Australian agriculture - MLA

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Soil Carbon Snapshot - Agriculture Victoria, accessed August 5, 2025,

Contextual Support Journal

Baseline map of organic carbon in Australian soil to support national carbon accounting and monitoring under climate change - PubMed Central, accessed July 28, 2025,

View Source