Acoustic Complexity Index (ACI)

AUS-TDG-CON-ACI General High confidence

Benchmark Value

No specific value — see range
Range: 130.5 to 137 index
Optimal Range: 130.5 to 137
Direction: Higher is desirable ↑
Form: OptimalRange

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.

Evidence & Context

"Grassy Woodland | 133.7 | 130.5 – 137.0"

Metric Definition:

Above-ground acoustic complexity calculated as the mean of the 95th percentile daily ACI values (mono channel recordings) across 10-minute blocks using standard soundscape analysis software.

Benchmark Definition:

Baseline reference above-ground ACI range for undisturbed grassy woodlands within a designated conservation reserve in Victoria.

Justification:

Represents the baseline reference above-ground ACI range for undisturbed grassy woodlands within a designated conservation reserve in Victoria, aligning directly with the target biome and land-use context.

Sources (1)

Preview of A REPORT ON A COMMUNITY PARTNERSHIP IN ECO-ACOUSTIC MONITORING IN MOUNT WORTH STATE PARK, VICTORIA, accessed May 14, 2026,
A REPORT ON A COMMUNITY PARTNERSHIP IN ECO-ACOUSTIC MONITORING IN MOUNT WORTH STATE PARK, VICTORIA, accessed May 14, 2026, Journal

A Report on a Community Partnership in Eco-Acoustic Monitoring in Brisbane Ranges

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Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

Preview of Ulloa, N., et al., 2021. scikit-maad: An open-source and modular toolbox for quantitative soundscape analysis in Python. Methods in Ecology and Evolution, 12(12).
Ulloa, N., et al., 2021. scikit-maad: An open-source and modular toolbox for quantitative soundscape analysis in Python. Methods in Ecology and Evolution, 12(12).
Direct Evidence GreyLiterature

Five Rivers Reserve (70) – Australian Acoustic Observatory

View Source

Context

  • Region Australia
  • Biome Temperate Dry Woodlands & Native Grasslands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Vegetation Woodland
  • Season Spring to early Summer
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 18 Jun 2026

Notes

The study reports a mean ACI of 133.7 for this specific vegetation class.

Related Benchmarks

Other benchmarks in the AUS-TDG-CON-ACI family.

— index High
Conservation / Protected Natural Areas · Pristine Reference · Forest · Spring to early Summer
OptimalRange Active v1
— index High
Conservation / Protected Natural Areas · Pristine Reference · Forest · Spring to early Summer
OptimalRange Active v1
— index High
Conservation / Protected Natural Areas · Pristine Reference · Forest · Spring to early Summer
OptimalRange Active v1
— index High
Conservation / Protected Natural Areas · Conservation Target · Woodland · Spring to early Summer
OptimalRange Active v1
— index High
Conservation / Protected Natural Areas · Pristine Reference · Shrubland · Spring to early Summer
OptimalRange Active v1
— index High
Conservation / Protected Natural Areas · Pristine Reference · Forest · Spring to early Summer
OptimalRange Active v1
— index High
Conservation / Protected Natural Areas · Pristine Reference · Forest · Spring to early Summer
OptimalRange Active v1