Basal Area

AUS-TMI-LVG-BAS General Moderate confidence

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 18 benchmarks together — the OptimalRange form drives the primary score, while 17 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

The "best available condition" is represented by a structurally intact open woodland with a basal area of 10-12 m²/ha.

Metric Definition:

Tree basal area, a measure of the cross-sectional area of tree stems per hectare, indicating ecosystem structure and function in grazing systems.

Benchmark Definition:

Basal area measures the cross-sectional area of tree stems per hectare, reflecting the structural complexity and ecological function of savanna woodlands under sustainable grazing management.

Justification:

Derived from proxy data of ecologically analogous mainland tropical savanna woodlands in North Queensland, supported by multiple studies indicating 10-12 m²/ha as a healthy, functional range.

Sources (1)

Preview of Drought-related tree death of savanna eucalypts in northern Australia
Drought-related tree death of savanna eucalypts in northern Australia Journal

Drought-related tree death of savanna eucalypts in northern Australia

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Livestock Grazing & Pasture
  • Assessment Not Stated
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 7 Jun 2026

Notes

Lower Critical Threshold: 2 m²/ha. Upper Detrimental Threshold: 15 m²/ha. Lower critical threshold below approximately 2 m²/ha indicates risk of ecosystem service compromise; upper detrimental threshold above approximately 15 m²/ha indicates woody thickening suppressing pasture productivity. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.