Acacia mangium / Stem biomass
Acacia mangium plantation, stem biomass from stump diameter (SB6)
As printed (Table 3, model SB6 (columns: β0, β1, RMSE, F, adjusted R2, AIC, average deviation, CF, DW))
In this library's units, ready to compute (kg)
Stem biomass = 1.0249 * exp(-2.519 + 2.175 * ln(D30))D30- Stem diameter at 30 cm, cm
Stem biomass only (bark included, oven-dry), so output is stem_biomass not agb. Form read as ln(SB) = β0 + β1 ln(dst) from the text calling SB6 the "ln–ln stump-based model"; the full model list is in a supplementary Table S1 that was not read. The Table 3 CF (1.0249) is applied in both forms. Table 3 caption says RMSE is in kg but the body values (about 0.2) are log-scale (CF 1.0193 matches exp(0.196²/2)), so the body is followed and rse is not stored. Table 3 gives no DBH range for the 25 calibration trees, so none is stored. Row label "Mangium" in Table 3 maps to this taxon.
doi:10.1007/s44415-026-00137-1 · Open access · copy we read
The ln–ln stump-based model (SB6) was parsimonious and produced adjusted R2 values of 0.945–0.968 across species
stump diameter (dst, measured at 30 cm above ground)
Biomass estimates refer specifically to stem biomass; branch, foliage, and root components were not included.
Calibration models were developed using 75 destructively sampled trees (25 per species, covering small, medium and large diameter classes)
All log transformations used natural logs (ln).
- Trees measured
- 25
- R²
- 0.9454
- Correction factor
- 1.0249 (applied)
- Method
- OLS on ln-transformed data (ln-ln), adjusted R2
- Where
- Ten plantation sites, Sylhet Division, Bangladesh
- Last checked
- 2026-11-02
On every build, the library's form and the paper's own form (in its units) must both give these values within 1%.
| Inputs | Expected | We get | From |
|---|---|---|---|
| D30 = 30 | 135 | 135 | Computed from the printed form hand-computed from the published form |
| D30 = 50 | 409 | 409 | Computed from the printed form hand-computed from the published form |
Related
- Acacia auriculiformis plantation, stem biomass from stump diameter (SB6) · Das & Chowdhury 2026 · D30
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- Planted Acacia mangium, West Java, stem biomass from D, all ages (model B) · Miyakuni et al. 2004 · DBH
- Acacia mearnsii Stem biomass from D and H (Table 3, model 1) · Shumie et al. 2024 · DBH + Height
- Acacia auriculiformis plantation, stem biomass from stump diameter (SB6) · same paper · Stem biomass
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