# Six Guanajuato oaks pooled, total aboveground biomass fitted directly (model 4)

Aboveground biomass equation for Quercus (six species: rugosa, obtusata, sideroxyla, coccolobifolia, laurina, candicans), Mexico, from Cortés-Sánchez et al. 2019. 165 trees, DBH 4.8–48.6 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Cortés-Sánchez et al. 2019 (Table 6, model 4):

> Bt = 0.057707 × (ρDn² × At)^0.989101

Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#equation

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

```
Aboveground biomass = 0.057707 * (rho * D^2 * H)^0.989101
```

Inputs: rho = Wood density (oven-dry mass / green volume) (g/cm³); D = Diameter at breast height (1.3 m) (cm); H = Total tree height (m).
The source's own form: 0.057707 * (rho * Dn^2 * At)^0.989101, with rho in g/cm3, At in m, Dn in cm; output in kg.
Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Quercus (six species: rugosa, obtusata, sideroxyla, coccolobifolia, laurina, candicans) (genus), family Fagaceae; broadleaf
- Where: Sierra de Santa Rosa, Guanajuato (bosques de encino). Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#where
- Biomes: temperate
- Stand: natural
- Trees measured: 165. Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#n_trees
- DBH range: 4.8–48.6 cm. Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#dbh
- Height range: 3.55–20.6 m. Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#height
- Method: Total biomass fitted directly (not as a sum of components). Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#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

Cortés-Sánchez, B. G., Ángeles-Pérez, G., De los Santos-Posadas, H. M., & Ramírez-Maldonado, H. (2019). Ecuaciones alométricas para estimar biomasa en especies de encino en Guanajuato, México. Madera y Bosques, 25(2), e2521799.

- DOI: https://doi.org/10.21829/myb.2019.2521799
- Access: open access
- Copy we read: https://myb.ojs.inecol.mx/index.php/myb/article/download/e2521799/1958
- Every equation from this source: https://treeallometry.org/sources/cortes-sanchez-2019/
- Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#source

## The facts, in the source's words

**Equation** (Table 6, model 4):

> Bt = 0.057707 × (ρDn² × At)^0.989101

Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#equation

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

> Un total de 165 árboles

Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#quote-fit-n-trees

**Our note:** Dn and At are diameter at breast height and total height (At measured after felling, stump height included). Adjusted R2 (not stored): 0.9577. Wood density rho from drying at 70 °C (g cm–3).

## 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 = 17.9, H = 8.7, rho = 0.7 | 103.7 | 103.7 | Computed from the printed form: computed from the published form (Table 6) |
| D = 35.5, H = 15.5, rho = 0.8 | 811.7 | 811.7 | Computed from the printed form: computed from the published form (Table 6) |

Cite: https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/#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: Cortés-Sánchez, B. G., Ángeles-Pérez, G., De los Santos-Posadas, H. M., & Ramírez-Maldonado, H. (2019). Ecuaciones alométricas para estimar biomasa en especies de encino en Guanajuato, México. Madera y Bosques, 25(2), e2521799. https://doi.org/10.21829/myb.2019.2521799

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Six Guanajuato oaks pooled, total aboveground biomass fitted directly (model 4)", checked 2026-11-02, https://treeallometry.org/equations/cortes-sanchez-2019-bt-m4/. 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/cortes-sanchez-2019-bt-m4.json
Report a problem: email info@restorationscope.com with the equation id (cortes-sanchez-2019-bt-m4) and where the right value appears.