Tree Allometrics

Equations / Stem biomass, without bark

Oak stem biomass under bark, Level 1

Stem biomass, without barkQuercus (Q. robur and Q. petraea)CzechiaRead from the original paperPeer-reviewed source

Fitted on these 2 species: Quercus robur, Quercus petraea

2 of the 2 species it was fitted on · iNaturalist photos, hover for credit
Equation

As printed (Table 3, model below table and Stem biomass under bark, Level 1 row, p. 115)

Biomass component = λ × exp(p₀ + p₁ × lnD); p₀ = −2.828, p₁ = 2.599, λ = 0.962

In this library's units, ready to compute (kg)

Stem biomass, without bark = 0.962 * exp(-2.828 + 2.599 * ln(D))
D
Diameter at breast height (1.3 m), cm

Stem biomass excludes bark. The printed correction factor multiplies the back-transformed prediction. Stem wood biomass was estimated using a conventional density. Adjusted R² is not stored as unadjusted R².

Source
–2.828 2.599
Equation · Table 3, stem biomass under bark, Level 1, p. 115
Biomass component = λ × exp(p0 + p1 × lnD
Equation · Table 3 formula, p. 115
correction factor (λ)
Equation · Table 3 caption, p. 115
Stem biomass under bark
Output · Table 3, p. 115
D (cm)
Units · Fig. 2, p. 111
AB (kg/tree)
Units · Fig. 4, p. 114
Quercus robur; Quercus petraea
taxon.members · Keywords, p. 109
different regions of the Czech Republic
Where · Abstract, p. 109
temperate region
Where · Keywords, p. 109
51 grown trees sampled from 6 sites
Trees measured · Abstract, p. 109
breast height diameter (D) ranging from 6 to 59 cm
Smallest DBH · Abstract, p. 109
breast height diameter (D) ranging from 6 to 59 cm
Largest DBH · Abstract, p. 109
0.985 0.166 0.962 13.4
Correction factor · Table 3, stem biomass under bark, Level 1, p. 115
linearized model (Eq. 3)
method · Methods, p. 112
conventional density of 580 kg/m³ for stem wood and 300 kg/m³ for bark, respectively
published.output unit · Methods, p. 111
Stem biomass under bark
output.excludes · Table 3, p. 115
Trees measured
51
DBH range
6–59 cm
Correction factor
0.962 (applied)
Method
Linearized regression
Where
Six sites in the Czech Republic
Last checked
2026-11-05
Calculate
393
Stem biomass, without bark (kg)
185
Carbon (kg), ×0.47
677
CO₂e (kg), ×44/12

Shaded: the DBH range the model was fitted on. Other inputs held at the values above.

Checks this equation passes

On every build, the library's form and the paper's own form (in its units) must both give these values within 1%.

InputsExpectedWe getFrom
D = 30393393Computed from the printed form
Computed from the printed coefficients and correction factor.

Report a problem with this equation · JSON

Related

Compare these curves