Tree Allometrics

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Terminalia superba stem biomass from Dbh

Stem biomassTerminalia superbaBeninnaturalRead from the original paper
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Equation

As printed (Eq. 3 and 5, p. 7; Table 4 (Model structure: ln(X) = x0 + x1ln(Dbh)), p. 10)

T. superba –2.38*** (0.16) 2.45*** (0.05) 98.31 16 0.01 35

In this library's units, ready to compute (kg)

Stem biomass = exp(-2.38 + 2.45 * ln(D) + 0.01)
D
Diameter at breast height (1.3 m), cm

Stem biomass only (stem = height to crown base); the authors say to multiply by a biomass expansion factor (IPCC 2006) to get aboveground biomass. Coefficients are printed to 2 decimals, so predictions are only as precise as that. σ²/2 is the paper's printed bias-correction term, added inside the exponent (Eq. 5); it is printed rounded to 2 decimals. Recommended-to-capture subset: species-specific Dbh-only biomass models for six species; the paper prefers species-specific models over the generic one.

Source
Terminalia superba 37 240 8.2–44.4
Trees measured · Table 1, p. 5 (number of sample trees)
Terminalia superba 37 240 8.2–44.4
Smallest DBH · Table 1, p. 5 (Dbh range, cm)
Trees measured
37
DBH range
8.2–44.4 cm
Method
ln-ln linear regression, back-transformed with exp(σ²/2) (printed σ²/2 is rounded to 2 decimals)
Where
Lama forest reserve, southern Benin (semi-deciduous forest)
Last checked
2026-11-02
Calculate
144
Stem biomass (kg)
67.7
Carbon (kg), ×0.47
248
CO₂e (kg), ×44/12
Fitted DBH range0200400600800510152025303540DBH (cm)Stem biomass (kg)Stem biomass

Shaded: the DBH range the model was fitted on. Other inputs held at the values above.

Checks this equation passes

On every build, the library's form and the paper's own form (in its units) must both give these values within 1%.

InputsExpectedWe getFrom
D = 20144144Computed from the printed form
computed from the published form (coefficients as printed to 2 decimals)
D = 40787787Computed from the printed form
computed from the published form (coefficients as printed to 2 decimals)

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