Foliage Height Diversity Index Calculator
Compute natural-log Shannon vertical foliage-area profile diversity and effective bins, caller equal/protocol matched height bins; not LAI or species diversity. Caller independently verifies units, applicability and matching conditions; no operational recipe, safety certification, causal efficacy or legal/resource classification is inferred.
Description
Vertical foliage diversity summarizes how measured foliage is distributed among chosen height bins.
Vertical foliage diversity summarizes how measured foliage is distributed among chosen height bins.1
A Shannon index depends on those bins and their weights, so it does not directly count species diversity. Use this tool to calculate foliage height diversity index from the supplied measurements and assumptions.
When to use Foliage Height Diversity Index Calculator
Use this tool to calculate foliage height diversity index from the supplied measurements and assumptions. Establish the species/site, survey protocol, units, sampled area or exposure, and the independently chosen reference or model.
How to use Foliage Height Diversity Index Calculator and understand its results
- Establish the species/site, survey protocol, units, sampled area or exposure, and the independently chosen reference or model.
- Enter observedFoliageAreaByHeightBin, using the field meanings and rules below, then run the tool.
- Read shannonVerticalFoliageDiversity, effectiveOccupiedHeightBins. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedFoliageAreaByHeightBin | Observed foliage area by height bin | list of number | Required |
Enter a nonempty list of nonnegative foliage-area weights with at least one positive weight. Normalize by a scaled total, compute −Σp ln(p) while ignoring zero shares, and return exp(index) as the effective number of occupied bins. Natural logarithms give index units of nats; bin boundaries and observations are independently supplied.
H=−Σ_(p>0)p ln(p); effectiveBins=exp(H) Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| shannonVerticalFoliageDiversity | Shannon Vertical Foliage Diversity; follow the units, sign, ordering and evidence convention stated above | number |
| effectiveOccupiedHeightBins | Effective Occupied Height Bins; follow the units, sign, ordering and evidence convention stated above | number |
{
"input": {
"observedFoliageAreaByHeightBin": [
1,
1,
2
]
},
"output": {
"shannonVerticalFoliageDiversity": 1.0397207708399179,
"effectiveOccupiedHeightBins": 2.82842712474619
}
}Limitations and assumptions
A Shannon index depends on those bins and their weights, so it does not directly count species diversity. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Canopy Gap Fraction Dot-Grid Aerial Photo Tool for this related task: A dot-count canopy-gap fraction depends on the sampling weights and independently annotated gap evidence.
Use Crown Closure Percentage Calculator when its separate inputs and assumptions fit the question: Crown closure uses independently annotated sky obstruction under a sampling design.
References
Similar or alternative tools
- Canopy Gap Fraction Dot-Grid Aerial Photo Tool
A dot-count canopy-gap fraction depends on the sampling weights and independently annotated gap evidence.
- Crown Closure Percentage Calculator
Crown closure uses independently annotated sky obstruction under a sampling design.