Equations / Stem biomass
Norway spruce, Czech Republic: Stem biomass from D and H/D (Table 2)
© Douglas Goldman · CC BY-SA · iNaturalistAs printed (Table 2 and Eq. 2, p. 113 and p. 110)
In this library's units, ready to compute (kg)
Stem biomass = exp(-3.62155 + 2.84648 * ln(D) + 1.0886 * ln(H/D)) * 1.002D- Diameter at breast height (1.3 m), cm
H- Total tree height, m
Coefficients, R2 and lambda as printed in Table 2 (lambda per Marklund 1987, Eq. 3, already multiplied in). H/D is slenderness ratio, tree height (m) over DBH (cm). Stem biomass excludes the stump. Not recommended for trees with D < 7 cm. Table 2 also gives models with site index (SI) or tree age (A) and crown biomass models, not added here (no canonical variable for SI or A; crown has no output quantity).
doi:10.17221/61/2017-jfs · Open access · copy we read
an extensive data set of 139 spruce trees collected in 25 stands on 15 sites
- Trees measured
- 139
- R²
- 0.96
- Correction factor
- 1.002 (applied)
- Method
- log-log linear regression with Marklund (1987) back-transformation correction factor
- Where
- 25 stands on 15 sites, Czech Republic (acidic and nutrient-medium sites)
- Last checked
- 2026-11-02
Shaded: the DBH range the model was fitted on. Other inputs held at the values above.
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 |
|---|---|---|---|
| D = 10, H = 10 | 18.8 | 18.8 | Computed from the printed form computed from the published form (coefficients as printed) |
| D = 25, H = 22 | 222.2 | 222.2 | Computed from the printed form computed from the published form (coefficients as printed) |
| D = 45, H = 30 | 875.4 | 875.4 | Computed from the printed form computed from the published form (coefficients as printed) |
Related
- Norway spruce, Czech Republic: Stem biomass from D (Table 2) · Čihák & Vejpustková 2018 · DBH
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- Picea spp. stem biomass, cross-sectional area at 0.3 m (NLS) · Flade et al. 2021 · D30
- Norway spruce stem biomass, young dense stands, N Sweden (Table 5) · Repola & Ahnlund Ulvcrona 2014 · DBH
- Norway spruce, Czech Republic: Total aboveground biomass from D and H/D (Table 2) · same paper · Aboveground biomass
- Norway spruce, Czech Republic: Total aboveground biomass from D (Table 2) · same paper · Aboveground biomass
- Norway spruce, Czech Republic: Foliage biomass from D and H/D (Table 2) · same paper · Foliage biomass
- Norway spruce, Czech Republic: Foliage biomass from D (Table 2) · same paper · Foliage biomass
- Norway spruce, Czech Republic: Stem biomass from D (Table 2) · same paper · Stem biomass