# Mopane root biomass from D²H (RM3)

Root biomass equation for Colophospermum mopane, Mozambique, from Lisboa et al. 2025. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Lisboa et al. 2025 (Table 6, model RM3, p. 10):

> ln(Y) = ln(a) + bln(D2H) + Ɛ RM3 – 2.797 ± 0.306 (– 3.450 to − 2.144) 0.803 ± 0.030 (0.739 to 0.867)

Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#equation

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

```
Root biomass = exp(-2.797 + 0.803 * ln(D^2 * H))
```

Inputs: D = Diameter at breast height (1.3 m) (cm); H = Total tree height (m).
The source's own form: exp(-2.797 + 0.803 * ln(D^2 * H)), with D in cm, H in m; output in kg.
Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#canonical

## What it covers

- Output: Root biomass, kg
- Taxon: Colophospermum mopane (species), family Fabaceae; broadleaf
- Where: Mabalane (Gaza) and Tambara (Manica) districts, mopane woodland. Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#where
- Biomes: tropical, dryland
- Stand: natural
- R²: 0.978. Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#r2
- Method: MM-estimator robust regression (ln Y = ln a + b ln(D²H)). Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#method
- Verification: read in the original source
- Last checked: 2026-11-01. Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#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

Lisboa, S.N., Macôo, S., Sitoe, A.A. (2025). Allometric equations for estimating above and belowground biomass of Colophospermum mopane in Mozambique. Scientific Reports, 15, 3464.

- DOI: https://doi.org/10.1038/s41598-025-87297-w
- Access: open access
- Copy we read: https://www.nature.com/articles/s41598-025-87297-w.pdf
- Every equation from this source: https://treeallometry.org/sources/lisboa-2025/
- Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#source

## The facts, in the source's words

**Equation** (Table 6, model RM3, p. 10):

> ln(Y) = ln(a) + bln(D2H) + Ɛ RM3 – 2.797 ± 0.306 (– 3.450 to − 2.144) 0.803 ± 0.030 (0.739 to 0.867)

Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#equation

**R²** (Table 7, model RM3, p. 10 (printed as a percentage)):

> RM3 ... R-square 97.80

Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#quote-fit-r2

**Our note:** Root model with D²H; the D+H model RM2 is left out because its height term is not significantly different from zero (95% CI –0.591 to 1.350). Root biomass (BGB) is stump plus coarse roots from excavation; fine roots under 2 mm were not sampled. n and ranges are not stated separately for the root sample, so they are omitted. No back-transformation correction factor is stated or applied. n = 120 sampled trees (Methods p. 3, Table 3), but Table 5 heads the total-AGB column 'n = 84', so the fitted n may be 84.

## 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, H = 9 | 43.8 | 43.8 | Computed from the printed form: computed from the published form |

Cite: https://treeallometry.org/equations/lisboa-2025-rm3-d2h/#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: Lisboa, S.N., Macôo, S., Sitoe, A.A. (2025). Allometric equations for estimating above and belowground biomass of Colophospermum mopane in Mozambique. Scientific Reports, 15, 3464. https://doi.org/10.1038/s41598-025-87297-w

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Mopane root biomass from D²H (RM3)", checked 2026-11-01, https://treeallometry.org/equations/lisboa-2025-rm3-d2h/. 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/lisboa-2025-rm3-d2h.json
Report a problem: email info@restorationscope.com with the equation id (lisboa-2025-rm3-d2h) and where the right value appears.