# Amazon arborescent palms, family-level AGB from diameter only

Aboveground biomass equation for Arecaceae, Peru, from Goodman et al. 2013. 97 trees, DBH 6–40 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Goodman et al. 2013 (Table 3 (y, x1, a, b, R2, n, RSE)):

> Family-level ln(AGB) ln(D) -3.3488 2.7483 0.802 97 0.588

Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#equation

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

```
Aboveground biomass = 1.1887 * exp(-3.3488 + 2.7483 * ln(D))
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: 1.1887 * exp(-3.3488 + 2.7483 * ln(D)), with D in cm; output in kg.
Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Arecaceae (family), family Arecaceae; palm
- Where: Western Amazonia: Madre de Dios (terra firme) and Loreto (wetland), Peru. Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#where
- Biomes: tropical
- Stand: natural
- Trees measured: 97. Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#n_trees
- DBH range: 6–40 cm. Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#dbh
- R²: 0.802. Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#r2
- Residual SE: 0.588. Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#rse
- Correction factor: 1.1887 (applied). Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#cf
- Method: OLS on ln(AGB) vs ln(D), 9 species pooled; Baskerville correction exp(RSE²/2). Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#method
- Verification: read in the original source
- Last checked: 2026-11-01. Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#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

Goodman, R. C., Phillips, O. L., del Castillo Torres, D., Freitas, L., Cortese, S. T., Monteagudo, A., & Baker, T. R. (2013). Amazon palm biomass and allometry. Forest Ecology and Management, 310, 994–1004.

- DOI: https://doi.org/10.1016/j.foreco.2013.09.045
- Access: paywalled
- Copy we read: http://eprints.whiterose.ac.uk/77906/7/Amazon%20Palm%20Biomass_Goodman_with_coversheet.pdf
- Every equation from this source: https://treeallometry.org/sources/goodman-2013/
- Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#source

## The facts, in the source's words

**Equation** (Table 3 (y, x1, a, b, R2, n, RSE)):

> Family-level ln(AGB) ln(D) -3.3488 2.7483 0.802 97 0.588

Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#equation

**Smallest DBH** (Table 3 caption):

> the family-level models without a height term are only valid for individuals with Hstem > 3 m and 6 ≤ D < 40 cm

Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#quote-fit-dbh-min-cm

**Correction factor** (Section 2.4, lines 220–221 (author post-print)):

> A correction factor, exp(RSE2/2), was applied to biomass estimates from logarithmically transformed models (Baskerville, 1972).

Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#quote-fit-cf

**Our note:** D measured at 1.3 m or above the highest stilt root. The correction factor exp(0.588²/2) is multiplied in, as the authors direct; Table 3 prints the log-scale coefficients without it. The authors recommend height-based species models (Hstem) where possible; D-only palm models are weak because many palms stop thickening.

## 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 | 157 | 157 | Computed from the printed form: computed from the Table 3 coefficients times exp(RSE²/2) |

Cite: https://treeallometry.org/equations/goodman-2013-palm-family-d/#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: Goodman, R. C., Phillips, O. L., del Castillo Torres, D., Freitas, L., Cortese, S. T., Monteagudo, A., & Baker, T. R. (2013). Amazon palm biomass and allometry. Forest Ecology and Management, 310, 994–1004. https://doi.org/10.1016/j.foreco.2013.09.045

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Amazon arborescent palms, family-level AGB from diameter only", checked 2026-11-01, https://treeallometry.org/equations/goodman-2013-palm-family-d/. 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/goodman-2013-palm-family-d.json
Report a problem: email info@restorationscope.com with the equation id (goodman-2013-palm-family-d) and where the right value appears.