Ground Cover - Tree Canopy

AUS-TMI-CON-TCC General High confidence

Benchmark Value

70 %
Range: 70 to — %
Optimal Range: 70 to —
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 9 benchmarks together — the OptimalRange form drives the primary score, while 8 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

According to the Australian Government's National Vegetation Information System (NVIS), rainforests and associated vegetation types are structurally defined as "closed forests" characterized by a tree canopy with "typically with greater than 70 per cent foliage cover".

Metric Definition:

Tree Canopy Cover is defined as the percentage of the ground shaded by the vertical projection of tree crowns.

Benchmark Definition:

The benchmark represents the minimum canopy cover for a healthy, structurally intact "closed forest" (rainforest) in Australia's protected tropical and subtropical maritime islands, based on the national vegetation classification system.

Justification:

The structural classification of high-integrity ecosystems as 'closed forest' provides a scientifically defensible quantitative benchmark, supported by qualitative descriptions of 'closed canopy' forests in high-integrity reference sites like the Lord Howe Island World Heritage Area and Pulu Keeling National Park.

Sources (1)

Preview of The ground layer of the rainforest
The ground layer of the rainforest Journal

The nutrient cycle in the rainforest - Internet Geography

View Source

Supporting Sources (21)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Ecological thresholds at the savanna-forest boundary: How ..., accessed August 2, 2025
(PDF) Ecological thresholds at the savanna-forest boundary: How ..., accessed August 2, 2025
Irrelevant

(PDF) Ecological thresholds at the savanna-forest boundary: How ..., accessed August 2, 2025

View Source
Preview of Australia's bioregions (IBRA) - DCCEEW, accessed July 15, 2025
Australia's bioregions (IBRA) - DCCEEW, accessed July 15, 2025
Contextual Support

Interim Biogeographic Regionalisation for Australia (IBRA), Version 7 (Regions)

View Source
Preview of Christmas Island National Park - DCCEEW, accessed July 30, 2025,
Christmas Island National Park - DCCEEW, accessed July 30, 2025,
Contextual Support Journal

Christmas Island National Park - DCCEEW, accessed August 2, 2025

View Source
Preview of Conservation Assessment of the Lord Howe Earthworm - DCCEEW, accessed August 2, 2025
Conservation Assessment of the Lord Howe Earthworm - DCCEEW, accessed August 2, 2025
Contextual Support Journal

Lowland Rainforest of Subtropical Australia ecological community ..., accessed August 2, 2025

View Source
Preview of Floristics and structure of the mossy cloud forest of Mt Gower summit, Lord Howe Island - CSIRO Publishing, accessed August 3, 2025,
Floristics and structure of the mossy cloud forest of Mt Gower summit, Lord Howe Island - CSIRO Publishing, accessed August 3, 2025,
Direct Evidence

Floristics and structure of the mossy cloud forest ... - CSIRO Publishing, accessed August 2, 2025

View Source
Preview of Floristics and structure of the mossy cloud forest of Mt Gower summit, Lord Howe Island, accessed August 2, 2025
Floristics and structure of the mossy cloud forest of Mt Gower summit, Lord Howe Island, accessed August 2, 2025
Direct Evidence Journal

Floristics and structure of the mossy cloud forest - of Mt Gower summit, Lord Howe Island - Ian Hutton, accessed August 2, 2025

View Source
Preview of Indigenous Protected Areas Project | TSRA - Torres Strait Regional Authority, accessed August 2, 2025
Indigenous Protected Areas Project | TSRA - Torres Strait Regional Authority, accessed August 2, 2025
Contextual Support Government

Indigenous Protected Areas Project | TSRA - Torres Strait Regional Authority, accessed August 2, 2025

View Source
Preview of Lord Howe Island - Wikipedia, accessed August 2, 2025
Lord Howe Island - Wikipedia, accessed August 2, 2025
Contextual Support

Cocos (Keeling) Islands - Wikipedia, accessed August 2, 2025

View Source
Preview of Lord Howe Island - Wikipedia, accessed July 30, 2025,
Lord Howe Island - Wikipedia, accessed July 30, 2025,
Direct Evidence GreyLiterature

Lord Howe Island - Wikipedia

View Source
Preview of Lord Howe Island Biodiversity Management Plan - DCCEEW, accessed August 3, 2025,
Lord Howe Island Biodiversity Management Plan - DCCEEW, accessed August 3, 2025,
Contextual Support

Norfolk Island Subtropical Forests | One Earth, accessed August 2, 2025

View Source
Preview of Lord Howe Island Group - UNESCO World Heritage Centre, accessed August 3, 2025,
Lord Howe Island Group - UNESCO World Heritage Centre, accessed August 3, 2025,
Contextual Support

Lord Howe Island Group - UNESCO World Heritage Centre

View Source
Preview of Lowland Rainforest of Subtropical Australia ecological community - listing advice, accessed July 20, 2025,
Lowland Rainforest of Subtropical Australia ecological community - listing advice, accessed July 20, 2025,
Contextual Support Journal

Biodiversity | Australia state of the environment 2021

View Source
Preview of Nature & Wildlife - Christmas Island, accessed August 2, 2025
Nature & Wildlife - Christmas Island, accessed August 2, 2025
Contextual Support GreyLiterature

Christmas Island - Wikipedia, accessed August 2, 2025

View Source
Preview of Nature | Pulu Keeling National Park | Parks Australia, accessed August 2, 2025
Nature | Pulu Keeling National Park | Parks Australia, accessed August 2, 2025
Contextual Support Government

Canopy - Rainforests - STRI Research - Smithsonian Institution, accessed August 2, 2025

View Source
Preview of Norfolk Island - DCCEEW, accessed August 2, 2025,
Norfolk Island - DCCEEW, accessed August 2, 2025,
Contextual Support Government

Draft Christmas Island Biodiversity Conservation Plan - DCCEEW, accessed August 2, 2025,

View Source
Preview of Norfolk Island Environment | Department of Infrastructure, Transport, Regional Development, Communications, Sport and the Arts, accessed August 2, 2025
Norfolk Island Environment | Department of Infrastructure, Transport, Regional Development, Communications, Sport and the Arts, accessed August 2, 2025
Contextual Support Government

Norfolk Island Environment | Department of Infrastructure, Transport, Regional Development, Communications, Sport and the Arts, accessed August 2, 2025

View Source
Preview of Norfolk Island Subtropical Forests | One Earth, accessed July 30, 2025,
Norfolk Island Subtropical Forests | One Earth, accessed July 30, 2025,
Contextual Support

Conservation | Norfolk Island National Park | Parks Australia, accessed August 2, 2025

View Source
Preview of Permanent Park Preserve - Lord Howe Island, accessed August 2, 2025
Permanent Park Preserve - Lord Howe Island, accessed August 2, 2025
Contextual Support GreyLiterature

Permanent Park Preserve - Lord Howe Island, accessed August 2, 2025

View Source
Preview of Plants | Christmas Island National Park | Parks Australia, accessed July 30, 2025,
Plants | Christmas Island National Park | Parks Australia, accessed July 30, 2025,
Direct Evidence Government

NVIS Fact sheet MVG 1 – Rainforests and vine thickets, accessed August 2, 2025

View Source
Preview of Torres Strait Indigenous Protected Areas (IPA's) - North West Atlas, accessed August 4, 2025,
Torres Strait Indigenous Protected Areas (IPA's) - North West Atlas, accessed August 4, 2025,
Contextual Support Journal

Torres Strait Indigenous Protected Areas (IPA's) - North West Atlas, accessed August 2, 2025

View Source
Preview of Weeding out a pesky problem on Lord Howe Island - CSIRO, accessed August 3, 2025,
Weeding out a pesky problem on Lord Howe Island - CSIRO, accessed August 3, 2025,
Contextual Support Government

How regenerative farming practices are revolutionising biodiversity in agriculture - Institute of Sustainability Studies

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Vegetation Forest
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 28 May 2026

Notes

No upper detrimental threshold — higher values are always better up to natural saturation. The optimal range is ≥70% up to the natural saturation point of the specific forest community.

Related Benchmarks

Other benchmarks in the AUS-TMI-CON-TCC family.

70 % High
Conservation / Protected Natural Areas · Pristine Reference · Forest
LowerThreshold Active v1