# Pan moist tropical AGB from DBH (Table 4, model 2)

Aboveground biomass equation for Mixed species, pan moist tropical forests (Campo-Ma'an plus data from Asia and South America), Pantropical, from Djomo et al. 2010. 443 trees, DBH 1–148 cm. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Djomo et al. 2010 (Table 4, model 2):

> 2. ln(M) = a + b ln(D)   a = −2.1801  b = 2.5624

Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#equation

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

```
Aboveground biomass = exp(-2.1801 + 2.5624 * ln(D))
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: exp(-2.1801 + 2.5624 * ln(D)), with D in cm; output in kg.
Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Mixed species, pan moist tropical forests (Campo-Ma'an plus data from Asia and South America) (mixed species); broadleaf
- Where: Moist tropical forests; Campo-Ma'an Cameroon, Brazil, Indonesia, Cambodia. Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#where
- Biomes: tropical
- Stand: natural
- Trees measured: 443. Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#n_trees
- DBH range: 1–148 cm. Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#dbh
- R²: 0.9671. Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#r2
- Residual SE: 0.444. Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#rse
- Method: log-log regression. Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#method
- Verification: read in the original source
- Last checked: 2026-11-01. Cite: https://treeallometry.org/equations/djomo-2010-pan-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

Djomo, A.N., Ibrahima, A., Saborowski, J., Gravenhorst, G. (2010). Allometric equations for biomass estimations in Cameroon and pan moist tropical equations including biomass data from Africa. Forest Ecology and Management, 260(10), 1873–1885.

- DOI: https://doi.org/10.1016/j.foreco.2010.08.034
- Access: paywalled
- Copy we read: https://uni-goettingen.de/de/document/download/4df40c701547ab5773871feade802dc2.pdf/Djomo_et_al_(2010)_FORECOLMANAG_allometric_equations.pdf
- Every equation from this source: https://treeallometry.org/sources/djomo-2010/
- Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#source

## The facts, in the source's words

**Equation** (Table 4, model 2):

> 2. ln(M) = a + b ln(D)   a = −2.1801  b = 2.5624

Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#equation

**Trees measured** (Table 4, model 2):

> N 443, RSE 0.444, Adj. R2 0.9671, D range 1–148

Cite: https://treeallometry.org/equations/djomo-2010-pan-d/#quote-fit-n-trees

**Our note:** Pooled with data from Brown (1997), Araújo et al. (1999), Nelson et al. (1999) and Ketterings et al. (2001); Africa contributes only the Campo-Ma'an trees. The paper reports a larger average error (29.5%) for its general equations than for Chave et al. (2005) (20.3%) in cross-site tests. Coefficients are used as printed; the paper does not state that the log-scale back-transformation correction factor is included, so none is applied. Reported R² is the adjusted R². Equation chosen from the paper's recommended set (7 of its equations captured).

## 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 = 30 | 688.9 | 688.9 | Computed from the printed form: hand-computed from the published form |

Cite: https://treeallometry.org/equations/djomo-2010-pan-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: Djomo, A.N., Ibrahima, A., Saborowski, J., Gravenhorst, G. (2010). Allometric equations for biomass estimations in Cameroon and pan moist tropical equations including biomass data from Africa. Forest Ecology and Management, 260(10), 1873–1885. https://doi.org/10.1016/j.foreco.2010.08.034

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Pan moist tropical AGB from DBH (Table 4, model 2)", checked 2026-11-01, https://treeallometry.org/equations/djomo-2010-pan-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/djomo-2010-pan-d.json
Report a problem: email info@restorationscope.com with the equation id (djomo-2010-pan-d) and where the right value appears.