# Piscidia piscipula, additive system S1 (D and H, Eq. 3-6): total aboveground biomass (sum of components)

Aboveground biomass equation for Piscidia piscipula (L.) Sarg., Mexico, from Cuevas Cruz et al. 2022. 17 trees, DBH 5.7–55 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Cuevas Cruz et al. 2022 (Eq. 6):

> Bt = Bf + Br + Brh (6)

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#equation

In this library's units, ready to compute (aboveground biomass in kg):

```
Aboveground biomass = (exp(-5.03971 + 1.6905 * ln(D) + 1.736484 * ln(H))) + (exp(-3.90699 + 2.239099 * ln(D) + 0.486697 * ln(H))) + (exp(-3.85536 + 1.166141 * ln(D) + 0.912641 * ln(H)))
```

Inputs: D = Diameter at breast height (1.3 m) (cm); H = Total tree height (m).
The source's own form: (exp(-5.03971 + 1.6905 * ln(Dn) + 1.736484 * ln(AT))) + (exp(-3.90699 + 2.239099 * ln(Dn) + 0.486697 * ln(AT))) + (exp(-3.85536 + 1.166141 * ln(Dn) + 0.912641 * ln(AT))), with AT in m, Dn in cm; output in kg.
Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Piscidia piscipula (L.) Sarg. (species), family Fabaceae; broadleaf
- Where: Escárcega, Campeche (selva mediana subperennifolia). Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#where
- Biomes: tropical
- Stand: natural
- Trees measured: 17. Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#n_trees
- DBH range: 5.7–55 cm. Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#dbh
- Height range: 8.12–21 m. Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#height
- Method: Additive nonlinear system of component equations fitted simultaneously by generalized method of moments (GMM). Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#checked_at

A missing fit statistic is one the source doesn't state, or that we haven't recorded; it is never estimated. Outside the stated DBH range or region, the equation is an extrapolation.

## Source

Cuevas Cruz, J. C., Aquino Ramírez, M., Kú Chalé, R. de la C., & Morales Sosa, I. J. (2022). Ecuaciones alométricas aditivas para estimar biomasa aérea y concentración de carbono de Piscidia piscipula (L.) Sarg. Madera y Bosques, 28(3), e2832356.

- DOI: https://doi.org/10.21829/myb.2022.2832356
- Access: open access
- Copy we read: https://myb.ojs.inecol.mx/index.php/myb/article/download/2356/2424
- Every equation from this source: https://treeallometry.org/sources/cuevas-2022/
- Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#source

## The facts, in the source's words

**Equation** (Eq. 6):

> Bt = Bf + Br + Brh (6)

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#equation

**Equation** (Eq. 3, Table 2 (S1)):

> Bf = e^[−β10+β11 ln(Dn)+β12 ln(AT)] + ε1 (3); Table 2, S1 Fuste: β10 5.03971, β11 1.6905, β12 1.736484

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#quote-expression

**Equation** (Eq. 4, Table 2 (S1)):

> Br = e^[−β20+β21 ln(Dn)+β22 ln(AT)] + ε2 (4); Table 2, S1 Ramas: β20 3.90699, β21 2.239099, β22 0.486697

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#quote-expression-2

**Equation** (Eq. 5, Table 2 (S1)):

> Brh = e^[−β30+β31 ln(Dn)+β32 ln(AT)] + ε3 (5); Table 2, S1 Ramillas con hojas: β30 3.85536, β31 1.166141, β32 0.912641

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#quote-expression-3

**Trees measured** (Resumen / Table 1):

> destructivo de 17 individuos

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#quote-fit-n-trees

**Our note:** The paper prints the intercept as a positive estimate and the model with a minus sign in front of it (e^[−β0 + ...]); applied that way. Adjusted R2 (not stored): stem 0.9911, branches 0.9789, twigs with leaves 0.8957, total 0.9919 (Table 3). Dn and AT are the paper's diameter at breast height and total height. Total is the sum of the component equations, as the paper defines it.

## Checks this equation passes

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

| Inputs | Expected | We get | From |
| --- | --- | --- | --- |
| D = 20.5, H = 12 | 145.2 | 145.2 | Computed from the printed form: computed from the published form (Table 2 coefficients, intercept with the printed minus sign) |
| D = 40.2, H = 17.1 | 795.5 | 795.5 | Computed from the printed form: computed from the published form (Table 2 coefficients, intercept with the printed minus sign) |

Cite: https://treeallometry.org/equations/cuevas-2022-s1-agb/#checks

The calculator on the page shows carbon as biomass × 0.47 (IPCC 2006 Guidelines, Vol. 4, Ch. 4, Table 4.3) and CO₂e as carbon × 44/12.

## How to cite

Cite the source for the equation: Cuevas Cruz, J. C., Aquino Ramírez, M., Kú Chalé, R. de la C., & Morales Sosa, I. J. (2022). Ecuaciones alométricas aditivas para estimar biomasa aérea y concentración de carbono de Piscidia piscipula (L.) Sarg. Madera y Bosques, 28(3), e2832356. https://doi.org/10.21829/myb.2022.2832356

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Piscidia piscipula, additive system S1 (D and H, Eq. 3-6): total aboveground biomass (sum of components)", checked 2026-11-02, https://treeallometry.org/equations/cuevas-2022-s1-agb/. Data CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Quotes are the authors' words.

Data for this equation: https://treeallometry.org/data/equations/cuevas-2022-s1-agb.json
Report a problem: email info@restorationscope.com with the equation id (cuevas-2022-s1-agb) and where the right value appears.