Water Nitrate

AUS-TMS-CON-WNI General Moderate confidence

Benchmark Value

0.07 mg/L

Thresholds: Lower: —, Upper: 0.07

Direction: Lower is desirable ↓

Form: UpperThreshold

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 8 benchmarks together — the OptimalRange form drives the primary score, while 7 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

Based on the sensitivity of oligotrophic systems to nutrient enrichment, particularly via eutrophication, the following table summarizes potential upper detrimental nitrate thresholds relevant to the management of Conservation / Protected Natural Areas in Australian Tropical Monsoonal Savannas: Table 1: Potential Upper Detrimental Nitrate Thresholds for Tropical Monsoonal Savanna Aquatic Ecosystems (Conservation Areas) Threshold Type Value (mg/L as NO3 2 BN) Source(s) & Rationale Early Ecological Shift / Eutrophication Risk ~0.07 Based on converted lower range from Brazilian savanna stream data (diatom/macroinvertebrate changes). Represents a highly precautionary level for sensitive oligotrophic systems.

Metric Definition:

Water nitrate concentration expressed as milligrams per liter as Nitrate-Nitrogen (NO3 2 BN).

Benchmark Definition:

This benchmark represents a precautionary upper threshold for nitrate concentration in water to avoid early ecological shifts and eutrophication risks in Conservation / Protected Natural Areas of Australian Tropical Monsoonal Savannas.

Justification:

Represents a highly precautionary level for sensitive oligotrophic systems.

Sources (1)

Preview of Diatom–water quality thresholds in South Australian streams indicate a need for more stringent water quality guidelines | Request PDF - ResearchGate, accessed May 11, 2025,

Diatom–water quality thresholds in South Australian streams indicate a need for more stringent water quality guidelines | Request PDF - ResearchGate, accessed May 11, 2025,

Validating species sensitivity distributions using salinity tolerance of riverine macroinvertebrates in the southern Murray–Darling Basin (Victoria, Australia) - Canadian Science Publishing

View Source

Supporting Sources (51)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Discharge-driven seasonal pattern of ionic solutes, suspended sediment and water clarity for a tropical savanna river in northern Australia - ResearchGate, accessed May 14, 2025,

(PDF) Discharge-driven seasonal pattern of ionic solutes, suspended sediment and water clarity for a tropical savanna river in northern Australia - ResearchGate, accessed May 14, 2025,

Contextual Support Journal

Environmental Water Requirements of Vallisneria nana in the Daly River, Northern Territory1 | Request PDF - ResearchGate

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Deriving guideline values using reference-site data - Water Quality Australia, accessed August 12, 2025

Direct Evidence Government

Water Quality Guidelines Home - Water Quality Australia

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Litchfield Savanna BASE Contextual, Soil Physico-Chemical Data ..., accessed May 20, 2025,

Contextual Support GreyLiterature

Litchfield Savanna BASE Contextual, Soil Physico-Chemical Data ..., accessed May 20, 2025,

View Source

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,

Contextual Support Journal

View Source

Surface water chemistry monitoring protocol to assess ... - DCCEEW, accessed May 20, 2025,

Contextual Support Methodology Source

Surface water chemistry monitoring protocol to assess ... - DCCEEW, accessed May 20, 2025,

View Source

Toxicant default guideline values for aquatic ecosystem protection ...

Direct Evidence

Toxicant default guideline values for aquatic ecosystem protection ...

Toxicant default guideline values for aquatic ecosystem protection ...

Direct Evidence

Toxicant default guideline values for aquatic ecosystem protection ...

Toxicant default guideline values for aquatic ecosystem protection ...

Direct Evidence

Default guideline values - Water Quality Australia

View Source

Toxicant default guideline values for aquatic ecosystem protection ..., accessed August 8, 2025

Direct Evidence Journal

Toxicant default guideline values for aquatic ecosystem protection ...

View Source

tuvalu-data.sprep.org, accessed May 20, 2025,

Contextual Support