Water Nitrate — Benchmark Detail - Nature Index

Benchmark Value

1 mg/L

Thresholds: Lower: —, Upper: 1

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

Contributing Benchmarks

OptimalRange Primary MaximumOnly Guard MinimumOnly Guard Point Guard MaximumOnly Guard Point Guard

Evidence & Context

The "Grading" value for 95% species protection is 1.0 mg/L of nitrate-nitrogen.

Metric Definition:

Long-term median nitrate concentration in mg/L nitrate-nitrogen (NO3−-N) indicating chronic toxicity threshold for aquatic species protection.

Benchmark Definition:

Chronic toxicity guideline value for nitrate-nitrogen concentration protecting 95% of freshwater species.

Justification:

Based on modern ecotoxicological guidelines adapted from Hickey (2013) and ANZG 2018 guidance.

Sources (1)

Preview of Updating nitrate toxicity effects on freshwater aquatic ... - Envirolink

Updating nitrate toxicity effects on freshwater aquatic ... - Envirolink Journal

Updating nitrate toxicity effects on freshwater aquatic ... - Envirolink, accessed July 22, 2025,

Supporting Sources (20)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Water Quality Degradation of Coastal Waterways in the Wet Tropics, Australia, accessed August 2, 2025,

(PDF) Water Quality Degradation of Coastal Waterways in the Wet Tropics, Australia, accessed August 2, 2025,

Contextual Support

Requirements for graziers | Environment, land and water ..., accessed July 19, 2025,

Preview of 5.7 Nitrates | Monitoring & Assessment | US EPA, accessed August 1, 2025

5.7 Nitrates | Monitoring & Assessment | US EPA, accessed August 1, 2025

Contextual Support Government

5.7 Nitrates | Monitoring & Assessment | US EPA, accessed August 1, 2025,

Preview of A conceptual model of nitrogen dynamics for the Great Barrier Reef catchments - Griffith Research Online, accessed July 22, 2025,

A conceptual model of nitrogen dynamics for the Great Barrier Reef catchments - Griffith Research Online, accessed July 22, 2025,

Contextual Support Journal

A conceptual model of nitrogen dynamics for the Great Barrier Reef catchments - Griffith Research Online

Preview of Daintree Rainforest Resources | Research & Monitoring | QLD - TERN Australia, accessed July 22, 2025,

Daintree Rainforest Resources | Research & Monitoring | QLD - TERN Australia, accessed July 22, 2025,

Contextual Support Government

Daintree Rainforest Resources | Research & Monitoring | QLD - TERN Australia, accessed July 22, 2025,

Preview of Dr Rebecca Bartley - CSIRO people, accessed July 22, 2025,

Dr Rebecca Bartley - CSIRO people, accessed July 22, 2025,

Contextual Support GreyLiterature

Dr Rebecca Bartley - CSIRO people, accessed July 22, 2025,

Preview of Environmental impacts of nitrate pollution - Aquamonitrix, accessed July 24, 2025,

Environmental impacts of nitrate pollution - Aquamonitrix, accessed July 24, 2025,

Contextual Support GreyLiterature

Environmental impacts of nitrate pollution - Aquamonitrix® - Nitrate and Nitrite Analyser, accessed May 11, 2025,

Preview of Herbert River Basin Environmental Values and Water Quality ..., accessed July 27, 2025,

Herbert River Basin Environmental Values and Water Quality ..., accessed July 27, 2025,

Direct Evidence Journal

Daintree and Mossman River Basins Environmental Values and ..., accessed July 22, 2025,

Preview of Improving water quality in the Great Barrier Reef - CSIRO, accessed July 22, 2025,

Improving water quality in the Great Barrier Reef - CSIRO, accessed July 22, 2025,

Contextual Support Government

Improving water quality in the Great Barrier Reef - CSIRO, accessed July 22, 2025,

Preview of Measurement of water quantity and quality - CSIRO, accessed July 22, 2025,

Measurement of water quantity and quality - CSIRO, accessed July 22, 2025,

Methodology Source Government

Measurement of water quantity and quality - CSIRO, accessed July 22, 2025,

Preview of Nitrate in freshwater and marine water - Water Quality Australia, accessed August 2, 2025,

Nitrate in freshwater and marine water - Water Quality Australia, accessed August 2, 2025,

Contextual Support

Nitrate - Water Quality Australia, accessed August 1, 2025

Preview of Nitrate Watch FAQs - Izaak Walton League, accessed July 22, 2025,

Nitrate Watch FAQs - Izaak Walton League, accessed July 22, 2025,

Contextual Support

Nitrate Watch FAQs - Izaak Walton League, accessed July 22, 2025,

Preview of Nutrient Availability in Tropical Rain Forests: The Paradigm of Phosphorus Limitation, accessed July 22, 2025,

Nutrient Availability in Tropical Rain Forests: The Paradigm of Phosphorus Limitation, accessed July 22, 2025,

Contextual Support GreyLiterature

Nutrient Availability in Tropical Rain Forests: The Paradigm of Phosphorus Limitation, accessed July 22, 2025,

Preview of Rainforest - WetlandInfo - Department of the Environment, Tourism, Science and Innovation, accessed July 18, 2025,

Rainforest - WetlandInfo - Department of the Environment, Tourism, Science and Innovation, accessed July 18, 2025,

Contextual Support Government

Nutrient distribution and cycling in a subtropical rainforest in New South Wales, accessed July 19, 2025,

Preview of Relationships between land use and nutrient concentrations in streams draining a 'wet-tropics' catchment in northern Australia - CSIRO PUBLISHING | Marine and Freshwater Research, accessed July 19, 2025,

Relationships between land use and nutrient concentrations in streams draining a 'wet-tropics' catchment in northern Australia - CSIRO PUBLISHING | Marine and Freshwater Research, accessed July 19, 2025,

Contextual Support Journal

Relationships between land use and nutrient ... - CSIRO Publishing, accessed July 22, 2025,

Preview of Science in Water Quality - Reef & Rainforest Research Centre, accessed August 2, 2025,

Science in Water Quality - Reef & Rainforest Research Centre, accessed August 2, 2025,

Contextual Support

Science in Water Quality - Reef & Rainforest Research Centre, accessed July 22, 2025,

Preview of TERN - Australia's Terrestrial Ecosystem Research Network, accessed July 30, 2025,

TERN - Australia's Terrestrial Ecosystem Research Network, accessed July 30, 2025,

Contextual Support GreyLiterature

The Great Western Woodlands TERN SuperSite: ecosystem monitoring infrastructure and key science learnings, accessed May 19, 2025

Preview of Terrestrial Ecosystem Research Network TERN Australia - Queensland science, accessed July 30, 2025,

Terrestrial Ecosystem Research Network TERN Australia - Queensland science, accessed July 30, 2025,

Contextual Support Government

TERN Ecosystem Research Infrastructure | School of Biological Sciences

Preview of Tour TERN's rainforest monitoring SuperSite | TERN Australia, accessed July 22, 2025

Tour TERN's rainforest monitoring SuperSite | TERN Australia, accessed July 22, 2025

Contextual Support Government

Robson Creek Flux Data Release 2022_v2 - TERN Data Discovery Portal

Preview of Water and Nitrogen Balance in Natural and Agricultural Systems in the Wet Tropics of North Queensland: A Review - Australian Banana Growers' Council, accessed July 18, 2025,

Water and Nitrogen Balance in Natural and Agricultural Systems in the Wet Tropics of North Queensland: A Review - Australian Banana Growers' Council, accessed July 18, 2025,

Contextual Support

(PDF) The impact of deforestation and pasture abandonment on soil ...

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 Conservation / Protected Natural Areas
Assessment Conservation Target
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 17 Mar 2026

Notes

This value represents a scientifically defensible upper detrimental threshold for conservation areas; concentrations at or above this level indicate chronic harm to aquatic life.

Related Benchmarks

Other benchmarks in the AUS-TSR-CON-WNI family.