Soil Phosphorus

AUS-TSR-LVG-SOP General Moderate confidence

Benchmark Value

No specific value — see range

Range: 10 to 15 mg/kg

Optimal Range: 10 to 15

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

Based on this synthesis, the proposed benchmark for a high-health, well-managed, mixed-species grazing system in the Australian tropical and subtropical rainforest biome is a Colwell-P range of 10–15 mg/kg for soils with low-to-moderate PBI.

Metric Definition:

Plant-available phosphorus concentration in soil measured by the Colwell-P test, representing the optimal range for balancing productivity and ecological health in managed tropical/subtropical pastures.

Benchmark Definition:

Optimal range of plant-available phosphorus in soil for sustainable grazing systems balancing productivity and ecological health.

Justification:

This range balances the need for productive growth of introduced pasture species and legumes while minimizing ecological harm to native species and reducing environmental runoff risk.

Sources (1)

Preview of Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA, accessed May 13, 2025,

Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA, accessed May 13, 2025, Government

Understanding soil tests for pastures | Soil | Farm management ..., accessed July 17, 2025

Supporting Sources (21)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Comparing the effects of continuous and time-controlled grazing systems on soil characteristics in Southeast Queensland - ResearchGate, accessed July 19, 2025,

(PDF) Comparing the effects of continuous and time-controlled grazing systems on soil characteristics in Southeast Queensland - ResearchGate, accessed July 19, 2025,

Contextual Support

Phosphorus Distribution in Soils from Australian Dairy and Beef Rearing Pastoral Systems, accessed July 18, 2025

Preview of ANIMAL SCIENCE IN AUSTRALIA, accessed July 28, 2025,

ANIMAL SCIENCE IN AUSTRALIA, accessed July 28, 2025,

Contextual Support GreyLiterature

Phosphorus supplementation of cattle in northern Australia - FutureBeef, accessed July 18, 2025

Preview of Critical phosphorus values from the Better Fertiliser Decisions for Pastures project: early insights from validation trials - BioOne Complete, accessed July 28, 2025,

Critical phosphorus values from the Better Fertiliser Decisions for Pastures project: early insights from validation trials - BioOne Complete, accessed July 28, 2025,

Contextual Support Journal

Soil nutrient critical limits | MBFP | More Beef from Pastures - MLA

Preview of Cycling of phosphorus in grazing systems - NSW Department of Primary Industries, accessed July 18, 2025,

Cycling of phosphorus in grazing systems - NSW Department of Primary Industries, accessed July 18, 2025,

Contextual Support GreyLiterature

Cycling of phosphorus in grazing systems - NSW Department of Primary Industries, accessed July 18, 2025

Preview of Do regenerative grazing management practices improve vegetation and soil health in grazed rangelands? Preliminary insights from a space-for-time study in the Great Barrier Reef catchments, Australia - CSIRO Publishing, accessed August 5, 2025,

Do regenerative grazing management practices improve vegetation and soil health in grazed rangelands? Preliminary insights from a space-for-time study in the Great Barrier Reef catchments, Australia - CSIRO Publishing, accessed August 5, 2025,

Contextual Support Journal

Ludwig, J.A., Bastin, G.N., Chewings, V.H., Eager, R.W., and Liedloff, A.C. (2005). Clearing savannas for use as rangelands in Queensland: Altered landscapes and water-erosion processes. Rangeland Journal, 27(2), 135-149.

Preview of Evidence of Large-Scale Chronic Eutrophication in the Great Barrier Reef: Quantification of Chlorophyll a Thresholds for Sustaining Coral Reef Communities - PubMed Central, accessed August 1, 2025

Evidence of Large-Scale Chronic Eutrophication in the Great Barrier Reef: Quantification of Chlorophyll a Thresholds for Sustaining Coral Reef Communities - PubMed Central, accessed August 1, 2025

Contextual Support Journal

Sediments and nutrients in north Queensland tropical streams: changes with agricultural development and pristine condition status, accessed July 18, 2025

Preview of Grassed up - Introduction - NSW Department of Primary Industries, accessed August 5, 2025,

Grassed up - Introduction - NSW Department of Primary Industries, accessed August 5, 2025,

Contextual Support Government

Why phosphorus is important - NSW Department of Primary Industries, accessed July 18, 2025

Preview of Improved maps of available phosphorus for the state of Queensland ..., accessed July 17, 2025,

Improved maps of available phosphorus for the state of Queensland ..., accessed July 17, 2025,

Contextual Support Journal

Updating the Phosphorus Map of Queensland - FutureBeef, accessed July 18, 2025

Preview of Indicative Soil Phosphorus Report | LongPaddock | Queensland Government

Indicative Soil Phosphorus Report | LongPaddock | Queensland Government

Contextual Support Government

Indicative Soil Phosphorus Report | LongPaddock | Queensland Government

Preview of Loss of phosphorus and nitrogen in runoff and subsurface drainage from high and low input pastures grazed by sheep in southern Australia - ResearchGate, accessed July 18, 2025,

Loss of phosphorus and nitrogen in runoff and subsurface drainage from high and low input pastures grazed by sheep in southern Australia - ResearchGate, accessed July 18, 2025,

Contextual Support Journal

Loss of phosphorus and nitrogen in runoff and subsurface drainage from high and low input pastures grazed by sheep in southern Australia - ResearchGate, accessed July 18, 2025

Preview of Nutrient loss and water quality under extensive grazing in the upper ...

Nutrient loss and water quality under extensive grazing in the upper ...

Contextual Support Journal

Evidence of Large-Scale Chronic Eutrophication in the Great Barrier Reef: Quantification of Chlorophyll a Thresholds for Sustaining Coral Reef Communities - PubMed Central, accessed July 18, 2025

Preview of Nutrient loss and water quality under extensive grazing in the upper Burdekin river catchment, North Queensland, accessed July 18, 2025,

Nutrient loss and water quality under extensive grazing in the upper Burdekin river catchment, North Queensland, accessed July 18, 2025,

Contextual Support Government

Nutrient loss and water quality under extensive grazing in the upper Burdekin river catchment, North Queensland, accessed July 18, 2025

Preview of Phosphorus - WA | Fact Sheets | soilquality.org.au, accessed July 21, 2025,

Phosphorus - WA | Fact Sheets | soilquality.org.au, accessed July 21, 2025,

Contextual Support GreyLiterature

Phosphorus - Qld | Fact Sheets | soilquality.org.au, accessed July 18, 2025

Preview of Phosphorus fertiliser management for pastures ... - CSIRO Publishing, accessed August 11, 2025

Phosphorus fertiliser management for pastures ... - CSIRO Publishing, accessed August 11, 2025

Contextual Support Journal

Phosphorus fertiliser management for pastures ... - CSIRO Publishing

Preview of Phosphorus fertiliser management for pastures based on native grasses in south-eastern Australia - ResearchGate, accessed July 18, 2025,

Phosphorus fertiliser management for pastures based on native grasses in south-eastern Australia - ResearchGate, accessed July 18, 2025,

Contextual Support Journal

Soil phosphorus and tree cover modify the effects of livestock grazing on plant species richness in Australian grassy woodland - ResearchGate

Preview of Phosphorus for high rainfall pastures - DPIRD's Digital library, accessed July 23, 2025,

Phosphorus for high rainfall pastures - DPIRD's Digital library, accessed July 23, 2025,

Contextual Support

Phosphorus Nutrition of Proteaceae in Severely Phosphorus-Impoverished Soils: Are There Lessons To Be Learned for Future Crops? - PubMed Central, accessed July 18, 2025

Preview of Phosphorus Nutrition of Proteaceae in Severely Phosphorus-Impoverished Soils: Are There Lessons To Be Learned for Future Crops? - PubMed Central, accessed August 4, 2025

Phosphorus Nutrition of Proteaceae in Severely Phosphorus-Impoverished Soils: Are There Lessons To Be Learned for Future Crops? - PubMed Central, accessed August 4, 2025

Contextual Support Journal

Phosphorus nutrition of phosphorus-sensitive Australian native plants: threats to plant communities in a global biodiversity hotspot - PMC

Preview of Soil nutrient critical limits | MBFP | More Beef from Pastures, accessed July 18, 2025,

Soil nutrient critical limits | MBFP | More Beef from Pastures, accessed July 18, 2025,

Contextual Support

Soil nutrient critical limits | MBFP | More Beef from Pastures, accessed July 18, 2025

Preview of Tropical Pasture - Barenbrug Australia, accessed July 18, 2025,

Tropical Pasture - Barenbrug Australia, accessed July 18, 2025,

Contextual Support Journal

P.PSH.1050 – Phosphorus management and requirements of tropical legume pasture swards - MLA, accessed July 18, 2025

Preview of What are the optimum nutrient targets for pastures? - Soil Health Knowledgebase, accessed August 5, 2025,

What are the optimum nutrient targets for pastures? - Soil Health Knowledgebase, accessed August 5, 2025,

Contextual Support Government

What are the optimum nutrient targets for pastures? - Soil Health Knowledgebase, accessed July 18, 2025

Preview of www.rrrc.org.au, accessed May 15, 2025,

www.rrrc.org.au, accessed May 15, 2025,

Contextual Support Journal

Sediments and nutrients in north Queensland tropical streams: changes with agricultural development and pristine condition status (Technical Report No. 62, Australian Rainforest CRC, 2006)

Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Livestock Grazing & Pasture
Assessment Not Stated
Evidence Type HealthyOperationalRange

Lifecycle

Status Active
Version 1
Effective From 10 Jun 2026

Notes

Lower Critical Threshold: <6 mg/kg is deficient, compromising animal health and pasture persistence. Upper Detrimental Threshold: Levels >20 mg/kg lead to significant loss of native grass biodiversity and increased risk of phosphorus runoff contributing to eutrophication. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.