Tree Allometrics

Betula papyrifera / Stem biomass

Betula papyrifera stem biomass, cross-sectional area at 0.3 m (LLRC)

Stem biomassBetula papyrifera · BetulaceaeCanadanaturalRead from the original paper
Photo of Betula papyrifera
Dezene Huber · CC0 · iNaturalist
Equation

As printed (Table 3, Eqs. 2-5)

Betula papyrifera Stems LLRC 3.970 52.9845 1.237 1.066 0.898 (columns: ln(β), β, α, CF, RMSE, R2); y = βx^α + ε (Eq. 2); y = βx^α × ε (Eq. 4), ε = e^(MSE/2) (Eq. 5)

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

Stem biomass = 52.9845 * 1.066 * (0.785398163397448 * D30^2)^1.237 / 1000
D30
Stem diameter at 30 cm, cm

Paper's predictor is cross-sectional area (cm2) of the stem(s) at 0.3 m; converted here to D30 as pi/4 * D30^2 (pi written as 0.785398163397448 * ...), so for multi-stemmed trees D30 is the equivalent diameter of the summed cross-sectional area. Paper output is in g dry mass; canonical form divides by 1000. LLRC correction factor applied as printed in the CF column. Fit range of the predictor is not stated, so none is given.

Source
Betula papyrifera 15
Trees measured · Table 1, No. of Samples
Trees measured
15
R²
0.898
Correction factor
1.066 (applied)
Method
linear log regression with correction factor (LLRC), y = β x^α × CF, x = cross-sectional area
Where
Sporadic to discontinuous permafrost zone, Taiga Plains and Taiga Shield ecozones, northwestern Canada
Last checked
2026-11-02
Calculate
0.233
Stem biomass (kg)
0.109
Carbon (kg), ×0.47
0.401
CO₂e (kg), ×44/12
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
D30 = 20.2330.233Computed from the printed form
computed from the published form (coefficients as printed)
D30 = 52.252.25Computed from the printed form
computed from the published form (coefficients as printed)
D30 = 87.187.18Computed from the printed form
computed from the published form (coefficients as printed)

Report a problem with this equation · JSON

Related

Compare these curves