Basal Area

AUS-ASP-AGR-BAS General Moderate confidence

Benchmark Value

No specific value — see range
Range: 3 to 6 m²/ha
Optimal Range: 3 to 6
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 16 benchmarks together — the OptimalRange form drives the primary score, while 15 guard(s) constrain the result.

Evidence & Context

The analysis indicates a mean Basal Area within these high-health reference sites of approximately 4.5 m²/ha. To account for natural variability across different soil types and rainfall gradients within the biome, it is more appropriate to represent this benchmark as a range. The data from these exclosure sites support a reference range of 3.0 to 6.0 m²/ha.

Metric Definition:

Basal Area (m²/ha) as a measure of woody vegetation structure in arid agroecosystems.

Benchmark Definition:

Basal Area is a measure of the cross-sectional area of woody vegetation per hectare, indicating ecosystem structural health in arid shrublands under agricultural crop production.

Justification:

Long-term grazing exclosures in Acacia aneura shrublands provide the best available proxy for a high-health woody vegetation structure in the absence of degrading land use.

Sources (1)

Preview of The Rangeland Journal - CSIRO PUBLISHING, accessed July 6, 2025,
The Rangeland Journal - CSIRO PUBLISHING, accessed July 6, 2025, Journal

Does grazing exclusion in Australia's rangelands affect biomass and debris carbon stocks?

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Preview of Maximizing retention of native biodiversity in Australian agricultural ...
Maximizing retention of native biodiversity in Australian agricultural ...
Contextual Support Journal

Does grazing exclusion in Australia's rangelands affect biomass and debris carbon stocks? - CSIRO Publishing, accessed April 29, 2025,

View Source
Preview of Productivity of Mallee Agroforestry Systems - — The ... - DBCA Library
Productivity of Mallee Agroforestry Systems - — The ... - DBCA Library
Direct Evidence Journal

Productivity of Mallee Agroforestry Systems - — The ... - DBCA Library

View Source

Context

  • Region Australia
  • Biome Arid Shrublands & Stony Plains
  • Land Use Agricultural Crop Production
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 22 Mar 2026

Notes

This benchmark is a recovery target reflecting the ecological potential when degrading pressures are minimized, not a pristine pre-European value. No upper detrimental threshold — higher values are always better up to natural saturation.