Basal Area

AUS-TMS-FOR-BAS General Moderate confidence

Benchmark Value

4 m²/ha
Direction: Higher is desirable ↑
Form: MinimumOnly

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

A sustained Basal Area below approximately 4-5 m²/ha (for stems >20cm DBH) could be indicative of significant degradation, extremely poor site conditions, or the consequences of overly intensive harvesting.

Metric Definition:

Basal area, typically expressed in square meters per hectare (m²/ha), is a fundamental metric in forestry and ecological assessment. It quantifies the cross-sectional area of tree stems at breast height per unit of ground area, thereby reflecting stand density, average tree size, accumulated biomass, and overall forest structure.

Benchmark Definition:

This benchmark represents a lower critical threshold of basal area below which the ecological health and sustainability of Tropical Monsoonal Savanna production forests are significantly compromised.

Justification:

This threshold is an estimation based on the lower end of observed ranges in natural systems and the general ecological understanding that very open stands may struggle with regeneration, be more susceptible to invasive species, or provide limited overall ecological services.

Sources (1)

Preview of Karan, M. et al. (2016) The Australian SuperSite Network...
Karan, M. et al. (2016) The Australian SuperSite Network... GreyLiterature

Hollow formation in the Eucalyptus miniata–E. tetrodonta open forests and savanna woodlands of tropical northern Australia - ResearchGate, accessed May 15, 2025

View Source

Supporting Sources (6)

Additional references from the underlying research that informed this benchmark.

Preview of depws.nt.gov.au, accessed May 15, 2025
depws.nt.gov.au, accessed May 15, 2025
Contextual Support Journal

depws.nt.gov.au, accessed May 15, 2025

View Source
Preview of era.dpi.qld.gov.au, accessed May 14, 2025,
era.dpi.qld.gov.au, accessed May 14, 2025,
Contextual Support GreyLiterature

Livestock grazing management and biodiversity conservation in Australian temperate grassy landscapes

View Source
Preview of Fire exclusion and the changing landscape of Queensland's Wet Tropics Bioregion 1. The extent and pattern of transition - ResearchGate
Fire exclusion and the changing landscape of Queensland's Wet Tropics Bioregion 1. The extent and pattern of transition - ResearchGate
Contextual Support GreyLiterature

Fire exclusion and the changing landscape of Queensland's Wet Tropics Bioregion 1. The extent and pattern of transition - ResearchGate, accessed May 15, 2025

View Source
Preview of Hutley, L. B., et al. (2011) Patterns and processes of carbon, water and energy cycles...
Hutley, L. B., et al. (2011) Patterns and processes of carbon, water and energy cycles...
Contextual Support GreyLiterature

Social‐ecological resilience thinking: Can indigenous culture guide environmental management? - ResearchGate, accessed May 15, 2025

View Source
Preview of Ironwood Erythrophleum chlorostachys in the Northern Territory ...
Ironwood Erythrophleum chlorostachys in the Northern Territory ...
Contextual Support GreyLiterature

Ironwood Erythrophleum chlorostachys in the Northern Territory ..., accessed May 15, 2025

View Source
Preview of The Science Behind Mining - Aluminium Stewardship Initiative, accessed May 16, 2025,
The Science Behind Mining - Aluminium Stewardship Initiative, accessed May 16, 2025,
Contextual Support Direct Evidence Journal

aluminium-stewardship.org, accessed May 15, 2025

View Source

Context

  • Region Australia
  • Biome Tropical Monsoonal Savannas
  • Land Use Production Forestry
  • Assessment Not Stated
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 26 May 2026

Notes

Value refers to stems >20cm DBH. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TMS-FOR-BAS family.