Basal Area — Benchmark Detail

Benchmark Value

No specific value — see range

Range: 5 to 12 m²/ha

Optimal Range: 5 to 12

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. The scoring engine uses 4 benchmarks together — the OptimalRange form drives the primary score, while 3 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MinimumOnly Guard OptimalRange Guard MinimumOnly Guard

Evidence & Context

The reference value represents the interquartile range (25th to 75th percentile) of basal area observed in high-quality reference sites (TERN AusPlots) within protected Acacia and Callitris woodlands in Australia's arid montane biome.

Metric Definition:

Basal Area (BA), the cross-sectional area of tree stems per unit of land.

Benchmark Definition:

This benchmark represents the typical basal area range of well-stocked, structurally complex, and resilient Acacia and Callitris woodlands in Australia's arid montane biome under pristine conditions.

Justification:

This range reflects a well-stocked, structurally complex, and resilient condition based on TERN AusPlots data.

Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

Preview of Synthesis of TERN AusPlots Rangelands survey data (2011-2019) and national best-practice guidelines for invasive species management in Australian arid rangelands.

Synthesis of TERN AusPlots Rangelands survey data (2011-2019) and national best-practice guidelines for invasive species management in Australian arid rangelands.

Direct Evidence

researchportal.murdoch.edu.au, accessed May 10, 2025

View Source

Context

Region Australia
Biome Arid Mountain Ranges & Uplands
Land Use Conservation / Protected Natural Areas
Assessment Pristine Reference
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 8 Jun 2026

Notes

Lower Critical Threshold: Basal areas below approximately 2-3 m²/ha are associated with a loss of structural complexity that compromises habitat for native fauna and may increase the hunting success of invasive predators like feral cats. No upper detrimental threshold — higher values are always better up to natural saturation. Interpretation requires landscape context.

Related Benchmarks

Other benchmarks in the AUS-AMR-CON-BAS family.