Water Nitrate

AUS-TSW-AQU-WNI General Moderate confidence

Benchmark Value

50 mg/L
Thresholds: Lower: —, Upper: 50
Direction: Lower 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 4 benchmarks together — the Point form drives the primary score, while 3 guard(s) constrain the result.

Contributing Benchmarks

Point Primary MaximumOnly Guard MaximumOnly Guard MaximumOnly Guard

Evidence & Context

Therefore, a robust and defensible benchmark that represents a state of high health, free from the physiological burden of managing elevated nitrate, is < 50 mg/L NO₃.

Metric Definition:

Water nitrate concentration representing the best available ecological condition for aquaculture in Australia's Temperate Semi-Arid Shrublands & Open Woodlands.

Benchmark Definition:

This benchmark defines the maximum acceptable water nitrate concentration in aquaculture systems within Australia's Temperate Semi-Arid Shrublands & Open Woodlands to prevent physiological stress in cultured species.

Justification:

The benchmark is based on the lowest concentration at which negative physiological effects have been documented in a relevant fish species, representing a state of high ecological health.

Sources (1)

Preview of Simultaneous exposure to nitrate and low pH reduces the blood oxygen-carrying capacity and functional performance of a freshwater fish | Conservation Physiology | Oxford Academic, accessed May 20, 2025,
Simultaneous exposure to nitrate and low pH reduces the blood oxygen-carrying capacity and functional performance of a freshwater fish | Conservation Physiology | Oxford Academic, accessed May 20, 2025, Journal

Simultaneous exposure to nitrate and low pH reduces the blood oxygen-carrying capacity and functional performance of a freshwater fish | Conservation Physiology | Oxford Academic, accessed May 20, 2025,

View Source

Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

Preview of Aquaculture Research to foster investor attraction and establishment ..., accessed July 13, 2025,
Aquaculture Research to foster investor attraction and establishment ..., accessed July 13, 2025,
Contextual Support Journal

(PDF) Survival and Growth of Silver Perch, Bidyanus bidyanus, a ..., accessed July 13, 2025,

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Context

  • Region Australia
  • Biome Temperate Semi-Arid Shrublands & Open Woodlands
  • Land Use Aquaculture
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 20 Mar 2026

Notes

No direct field data exists for a best-practice inland saline aquaculture system in this specific biome; this benchmark is derived. The benchmark is based on sub-lethal stress thresholds and management principles of keeping nitrate as low as practically achievable.