Tree Allometrics

Equations / Aboveground biomass

Cerrado sensu stricto wood + bark dry mass from D30 (quadratic, Fig. 5)

Aboveground biomassCerrado sensu stricto woody species (47 species)BrazilnaturalRead from the original paper
Many species, no single photo
Equation

As printed (Figura 5, p. 124)

y = 26,501 - 7,0631*x + 0,5169*x2

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

Aboveground biomass = 26.501 - 7.0631 * D30 + 0.5169 * D30^2
D30
Stem diameter at 30 cm, cm

x is the stem diameter at 30 cm above ground (D30), not DBH. Total = wood plus bark of trunk and branches; branches under 3 cm basal diameter were removed before weighing, and the paper does not say how foliage was treated, so no exclusion is declared. The paper states 3 trees per diameter class in seven classes but not a total n, so n_trees and the fitted diameter range are left out.

Source
R2 = 0,92
R² · Figura 5, p. 124
em função do diâmetro a 30 cm de altura do solo
input · Resumo
Massa seca total (kg/árv.)
Output · Figura 5, p. 124
R²
0.92
Method
Quadratic regression y = b0 + b1x + b2x2 (SAEG); best of 12 equations tested
Where
Fazenda Água Limpa, Universidade de Brasília, Distrito Federal
Last checked
2026-11-02
Calculate
7.56
Aboveground biomass (kg)
3.553
Carbon (kg), ×0.47
13.03
CO₂e (kg), ×44/12
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
D30 = 107.567.56Computed from the printed form
computed from the printed Figure 5 equation
D30 = 209292Computed from the printed form
computed from the printed Figure 5 equation

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