Soil Phosphorus

AUS-TGP-FOR-SOP General Moderate confidence

Benchmark Value

20 mg/kg
Direction: Higher is desirable ↑
Form: MaximumOnly

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 5 benchmarks together — the OptimalRange form drives the primary score, while 4 guard(s) constrain the result.

Evidence & Context

An available soil phosphorus level exceeding 20 mg/kg is considered detrimental to the environmental health and overall ecosystem function of a production forest in this biome.

Metric Definition:

Available soil phosphorus concentration measured by Colwell-P or equivalent method

Benchmark Definition:

This benchmark defines the upper detrimental threshold of soil available phosphorus above which ecological degradation and physiological stress occur in production forestry within this biome.

Justification:

Based on evidence of direct P toxicity in Eucalyptus species and ecosystem degradation with native understorey loss above this level.

Sources (1)

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 Journal

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

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Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Establishment of critical nutrient levels in soil and plant for eucalyptus - ResearchGate
(PDF) Establishment of critical nutrient levels in soil and plant for eucalyptus - ResearchGate
Contextual Support Journal

(PDF) Establishment of critical nutrient levels in soil and plant for eucalyptus - ResearchGate

View Source
Preview of Establishment of critical nutrient levels in soil and plant for eucalyptus
Establishment of critical nutrient levels in soil and plant for eucalyptus
Contextual Support Journal

Establishment of critical nutrient levels in soil and plant for eucalyptus

View Source
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 Production Forestry
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 8 Jun 2026

Notes

Represents a state of ecological degradation and/or physiological stress.