# Planted Acacia mangium, West Java, aboveground biomass from D, 3-year stand (model A)

Aboveground biomass equation for Acacia mangium, Indonesia, from Miyakuni et al. 2004. 15 trees. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Miyakuni et al. 2004 (Table 5, model A, stand age 3):

> Y = a·dbh^b; a = 0.0414, b = 2.7523, r2 = 0.9727

Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#equation

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

```
Aboveground biomass = 0.0414 * D^2.7523
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: 0.0414 * dbh^2.7523, with dbh in cm; output in kg.
Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Acacia mangium (species), family Fabaceae; broadleaf
- Where: Maribaya and Tenjo ranger districts (Parungpanjang), Perhutani, West Java. Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#where
- Biomes: tropical
- Stand: plantation
- Trees measured: 15. Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#n_trees
- R²: 0.9727. Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#r2
- Method: log-linear least squares of Y = a·dbh^b. Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#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

Miyakuni, K., Heriansyah, I., Heriyanto, N. M., & Kiyono, Y. (2004). Allometric Biomass Equations, Biomass Expansion Factors and Root-to-shoot Ratios of Planted Acacia mangium Willd. Forests in West Java, Indonesia. Journal of Forest Planning, 10(2), 69-76.

- DOI: https://doi.org/10.20659/jfp.10.2_69
- Access: open access
- Copy we read: https://www.jstage.jst.go.jp/article/jfp/10/2/10_KJ00007911299/_pdf
- Every equation from this source: https://treeallometry.org/sources/miyakuni-2004/
- Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#source

## The facts, in the source's words

**Equation** (Table 5, model A, stand age 3):

> Y = a·dbh^b; a = 0.0414, b = 2.7523, r2 = 0.9727

Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#equation

**Trees measured** (Destructive Sampling to Measure the Biomass of Individual Trees, p. 72):

> We selected 15 trees from the 3-year-old stand, 12 trees from the 5-year-old stand, 16 trees from the 8-year-old stand, and 16 trees from the 10-year-old stand

Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#quote-fit-n-trees

**Our note:** Model A: 3-year-old stand. Fitted in log space (log-linear) and printed as a power law; the paper states no back-transformation correction factor and none is applied. The paper does not print the sampled dbh range. Aboveground biomass is the sum of the above-ground organs as defined by the authors (Yag).

## 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 = 5 | 3.47 | 3.47 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 10 | 23.4 | 23.4 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 20 | 158 | 158 | Computed from the printed form: computed from the published form (coefficients as printed) |

Cite: https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/#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: Miyakuni, K., Heriansyah, I., Heriyanto, N. M., & Kiyono, Y. (2004). Allometric Biomass Equations, Biomass Expansion Factors and Root-to-shoot Ratios of Planted Acacia mangium Willd. Forests in West Java, Indonesia. Journal of Forest Planning, 10(2), 69-76. https://doi.org/10.20659/jfp.10.2_69

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Planted Acacia mangium, West Java, aboveground biomass from D, 3-year stand (model A)", checked 2026-11-02, https://treeallometry.org/equations/miyakuni-2004-agb-a-3yr/. 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/miyakuni-2004-agb-a-3yr.json
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