Tree Allometrics

Equations / Root biomass

White birch root biomass from D only (MS-2) (Table 5)

Root biomassBetula platyphylla · BetulaceaeChinanaturalRead from the original paper
Photo of Betula platyphylla
© harum.koh · CC BY-SA · iNaturalist
Equation

As printed (Table 5 (MS-2), White birch, root row; model form Eq. (14) structure)

Wr = e^β10 · D^β11; White birch | Root | -3.0968 | 2.3095

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

Root biomass = exp(-3.0968 + 2.3095 * ln(D))
D
Diameter at breast height (1.3 m), cm

White birch, additive system MS-2 (Table 5); W = exp(b0) * D^b1 (Eqs. 16 form per Table caption). Ranges and n from Table 2. The b0 column is the exponent of e (W = e^b0 ...), as in Eq. (14). Stem includes bark. Root excludes fine roots <5 mm. No R2 recorded (adjusted R2 only).

Source
138 Dahurian larch trees and 108 white birch trees were destructively sampled
Trees measured · Section 2.2
Trees measured
108
DBH range
1.4–20.5 cm
Height range
3.1–21 m
Method
seemingly unrelated regression (SUR), additive system, W = exp(b0) D^b1 H^b2
Where
Eastern Daxing'an Mountains, Heilongjiang, northeast China
Last checked
2026-11-02
Calculate
1.111
Root biomass (kg)
0.522
Carbon (kg), ×0.47
1.914
CO₂e (kg), ×44/12
Fitted DBH range050100150200250510152025303540DBH (cm)Root biomass (kg)Root biomass

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 = 41.111.11Computed from the printed form
computed from the published form (coefficients as printed)
D = 109.229.22Computed from the printed form
computed from the published form (coefficients as printed)
D = 1835.835.8Computed from the printed form
computed from the published form (coefficients as printed)

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