Soil Phosphorus

AUS-TGP-FOR-SOP General High confidence

Benchmark Value

No specific value — see range

Range: 8 to 15 mg/kg

Optimal Range: 8 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. 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

The optimal range for available soil phosphorus, representing the best available condition, is identified as 8 to 15 mg/kg.

Metric Definition:

Optimal range of available soil phosphorus supporting high productivity without ecological harm.

Benchmark Definition:

Represents the target 'best available condition' balancing high productivity with ecological safety in temperate grassy woodlands production forestry.

Justification:

Anchored by field data from high-yield commercial plantations showing optimal growth between 8.5 and 14.6 mg/kg and capped at 15 mg/kg to remain below damage thresholds.

Sources (1)

Establishment of critical nutrient levels in soil and plant for eucalyptus Journal

Establishment of critical nutrient levels in soil and plant for eucalyptus

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Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

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

Australian dryland soils are acidic and nutrient-depleted, and have unique microbial communities compared with other drylands - PMC

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Preview of Phosphorus uptake and toxicity are delimited by mycorrhizal symbiosis in P-sensitive Eucalyptus marginata but not in P-tolerant Acacia celastrifolia - PubMed Central

Phosphorus uptake and toxicity are delimited by mycorrhizal symbiosis in P-sensitive Eucalyptus marginata but not in P-tolerant Acacia celastrifolia - PubMed Central

Contextual Support Journal

Phosphorus uptake and toxicity are delimited by mycorrhizal symbiosis in P-sensitive Eucalyptus marginata but not in P-tolerant Acacia celastrifolia - PubMed Central

View Source

Context

Region Australia
Biome Temperate Grassy Woodlands & Plains
Land Use Production Forestry
Assessment Conservation Target
Vegetation Forest
Evidence Type TargetCondition

Lifecycle

Status Active
Version 1
Effective From 24 Mar 2026

Notes

Managing soil P within this 8–15 mg/kg window allows for maximization of productive potential while minimizing risk of harm to trees or native understorey biodiversity.

Related Benchmarks

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