Basal Area

AUS-TMI-FOR-BAS General Moderate confidence

Benchmark Value

19 m²/ha
Direction: Higher 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 15 benchmarks together — the OptimalRange form drives the primary score, while 14 guard(s) constrain the result.

Evidence & Context

The concept of an upper detrimental threshold for ecological health is not well-supported by evidence; rather, values above 19 m²/ha represent a natural Saturation Point where net stand productivity declines due to intense competition and self-thinning.

Metric Definition:

Basal area as total cross-sectional area of tree stems per hectare.

Benchmark Definition:

An upper boundary of basal area representing natural carrying capacity or self-thinning limit in production forestry on tropical and subtropical maritime islands in Australia.

Justification:

Based on the 95th percentile of basal area (P95 BA) of the analogous subtropical eucalypt forest.

Sources (1)

Preview of Native Forests Show Resilience to Selective Timber Harvesting in Southeast Queensland, Australia
Native Forests Show Resilience to Selective Timber Harvesting in Southeast Queensland, Australia Journal

Resilience of selectively harvested forests to timber harvesting in subtropical Australia

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Production Forestry
  • Assessment Not Stated
  • Evidence Type DegradationThreshold

Lifecycle

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

Notes

Beyond this point, net stand productivity declines due to intense competition; not a threshold of ecological degradation. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.