Basal Area

AUS-AIF-AGR-BAS General Moderate confidence

Benchmark Value

No specific value — see range
Range: 15 to 20 m²/ha
Thresholds: Lower: 15, Upper: 20
Optimal Range: 15 to 20
Direction: Lower 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

Once Basal Area rises into the range typical of a moderate woodland (e.g., exceeding 15 to 20 m²/ha), the negative competitive impacts on crop yield would become unsustainable for a viable agricultural operation.

Metric Definition:

Basal Area is the cross-sectional area of tree stems per unit of ground area.

Benchmark Definition:

This benchmark defines the upper basal area threshold above which competition for water causes unsustainable crop yield loss, making integrated cropping economically unviable in Australia's Arid Inland Floodplains.

Justification:

The upper threshold is based on evidence of competition for water causing unsustainable crop yield loss in water-limited environments.

Sources (1)

Preview of Regional differences in tree–crop competition due to soil, climate and management - CSIRO Publishing
Regional differences in tree–crop competition due to soil, climate and management - CSIRO Publishing Journal

Regional differences in tree–crop competition due to soil, climate and management - CSIRO Publishing

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Preview of Managing environmental flows in an agricultural landscape: the Lower Gwydir floodplain - DCCEEW, accessed July 18, 2025,
Managing environmental flows in an agricultural landscape: the Lower Gwydir floodplain - DCCEEW, accessed July 18, 2025,
Direct Evidence

Vegetation mapping of the Barwon-Darling and Condamine ...

View Source
Preview of Scattered paddock trees - Local Land Services - NSW Government
Scattered paddock trees - Local Land Services - NSW Government
Contextual Support GreyLiterature

Scattered paddock trees - Local Land Services - NSW Government

View Source
Preview of Tree decline and the future of Australian farmland biodiversity - PMC - PubMed Central
Tree decline and the future of Australian farmland biodiversity - PMC - PubMed Central
Contextual Support Journal

Tree decline and the future of Australian farmland biodiversity - PMC - PubMed Central

View Source

Context

  • Region Australia
  • Biome Arid Inland Floodplains & Ephemeral River Systems
  • Land Use Agricultural Crop Production
  • Assessment Pristine Reference
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 3
  • Effective From 22 Mar 2026

Notes

Above this threshold, integrated cropping becomes economically unviable.