# Baia et al. 2025: Tree height-diameter allometry and implications for biomass estimates in Northeastern Amazonian forests

Baia, A.L.P., Nascimento, H.E.M., Guedes, M., Hilário, R., Toledo, J.J. (2025). Tree height-diameter allometry and implications for biomass estimates in Northeastern Amazonian forests. PeerJ, 13, e18974.

- DOI: https://doi.org/10.7717/peerj.18974
- Access: open access
- Copy we read: https://europepmc.org/article/MED/40093411
- Status: no retraction or correction notice recorded (Crossref is asked weekly); last checked 2026-11-02
- Page: https://treeallometry.org/sources/baia-2025/

## Equations from this source (7)

### Height from DBH, Michaelis-Menten model, both forests pooled

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 1–139.5 cm. 1,962 trees.

As printed (Table 1 (form) and Table 2, Both forests block):

> H = a × DBH/(b + DBH) + ε ; Table 2: Michaelis-Menten a 42.1399 0.764 4.935 0.75 11,835.8 | b 21.77561 0.849

Page: https://treeallometry.org/equations/baia-2025-both-michaelis-menten/

### Height from DBH, Michaelis-Menten model, terra-firme

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 1–109.1 cm. 1,156 trees.

As printed (Table 1 (form) and Table 2, Terra-firme block):

> H = a × DBH/(b + DBH) + ε ; Table 2: Michaelis-Menten a 51.09644 0.988 4.021 0.87 6,501.9 | b 25.11112 0.99

Page: https://treeallometry.org/equations/baia-2025-terra-firme-michaelis-menten/

### Height from DBH, Michaelis-Menten model, várzea

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 5–139.5 cm. 806 trees.

As printed (Table 1 (form) and Table 2, Várzea block):

> H = a × DBH/(b + DBH) + ε ; Table 2: Michaelis-Menten a 33.09269 0.811 4.164 0.65 4,590.9 | b 18.42734 1.032

Page: https://treeallometry.org/equations/baia-2025-varzea-michaelis-menten/

### Height from DBH, Quadratic model, both forests pooled

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 1–139.5 cm. 1,962 trees.

As printed (Table 1 (form) and Table 2, Both forests block):

> H = exp(a + b × ln(DBH) + c × ln(DBH)²) + ε ; Table 2: Quadratic a 0.48064 0.092 4.937 0.75 11,838.5 | b 1.16793 0.059 | c −0.10905 0.009

Page: https://treeallometry.org/equations/baia-2025-both-quadratic/

### Height from DBH, Quadratic model, terra-firme

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 1–109.1 cm. 1,156 trees.

As printed (Table 1 (form) and Table 2, Terra-firme block):

> H = exp(a + b × ln(DBH) + c × ln(DBH)²) + ε ; Table 2: Quadratic a 0.63296 0.081 4.018 0.87 6,501.2 | b 1.11213 0.052 | c −0.09504 0.008

Page: https://treeallometry.org/equations/baia-2025-terra-firme-quadratic/

### Height from DBH, Quadratic model, várzea

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 5–139.5 cm. 806 trees.

As printed (Table 1 (form) and Table 2, Várzea block):

> H = exp(a + b × ln(DBH) + c × ln(DBH)²) + ε ; Table 2: Quadratic a 0.51504 0.158 4.161 0.65 4,590.7 | b 1.07489 0.1 | c −0.10005 0.015

Page: https://treeallometry.org/equations/baia-2025-varzea-quadratic/

### Height from DBH, Weibull model, both forests pooled

Height for Mixed Amazonian forest trees (367 species in terra-firme, 65 in várzea), Brazil. Inputs: DBH. DBH 1–139.5 cm. 1,962 trees.

As printed (Table 1 (form) and Table 2, Both forests block):

> H = a × (1 − exp(−b × DBHc)) + ε ; Table 2: Weibull a 35.07114 1.032 4.934 0.75 11,836.6 | b 0.0661 0.003 | c 0.85189 0.028

Page: https://treeallometry.org/equations/baia-2025-both-weibull/