Soil Phosphorus
Benchmark Value
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 10 benchmarks together — the OptimalRange form drives the primary score, while 9 guard(s) constrain the result.
Evidence & Context
The evidence from mainland northern Australian grazing systems consistently identifies a soil P level of 5 mg/kg (bicarbonate-extractable P) or less as 'deficient'.
Bicarbonate-extractable phosphorus (P) level in soil below which pasture productivity and animal health are severely compromised.
This threshold marks the minimum soil phosphorus level needed to maintain sustainable grazing and animal health in tropical maritime island pastures, based on mainland data.
Below 5 mg/kg soil P, pasture productivity and cattle health decline significantly, risking land degradation.
Sources (1)
Phosphorus management of beef cattle in northern Australia
View SourceSupporting Sources (36)
Additional references from the underlying research that informed this benchmark.
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View SourcePhosphorus Nutrition of Proteaceae in Severely Phosphorus-Impoverished Soils: Are There Lessons To Be Learned for Future Crops? - PubMed Central, accessed July 18, 2025
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