Tsuga canadensis / Aboveground biomass
Canadian national equation, eastern hemlock, dbh only (sum of wood, bark, branches, foliage; Table 3)
Aboveground biomassTsuga canadensis · PinaceaeCanadaRead from the original paper
© Ian Manning · CC BY · iNaturalistEquation
As printed (Eq. 2)
y wood = β wood1D βwood2 + ewood
In this library's units, ready to compute (kg)
Aboveground biomass = 0.0619 * D^2.3821 + 0.0139 * D^2.3282 + 0.0217 * D^2.2653 + 0.0776 * D^1.6995D- Diameter at breast height (1.3 m), cm
Total aboveground biomass = wood + bark + branches + foliage, each fitted as its own equation; the total is their sum (additivity by construction). r2 is the adjusted R² (AdjRSq) of this compartment in Table 5. Fitted on the original scale (weighted nonlinear seemingly unrelated regression), so there is no back-transform correction. Dead branches, cones and fruits are not part of aboveground biomass in this work (Materials). Stand type was not always recorded. Ung, Bernier & Guo (2008) later revised parameters for some species with British Columbia data; not used here.
Source
doi:10.1139/x05-112 · Paywalled · copy we read
y bark = β bark1D βbark2 + e bark
y branches = β branches1D βbranches2 + e branches
y foliage = β foliage1D βfoliage2 + efoliage
Eastern hemlock bwood1 0.0619
bwood2 2.3821
bbark1 0.0139
bbark2 2.3282
bbranches1 0.0217
bbranches2 2.2653
bfoliage1 0.0776
bfoliage2 1.6995
Eastern hemlock 235 24.1±0.9 14.4±0.4 286.9±20.5
(1.3;51.4) (2.3;26.5) (0.6;1406.6)
Total 0.0156 0.94 78.0 3.60 0.1216 0.95 68.8 2.89
- Trees measured
- 235
- DBH range
- 1.3–51.4 cm
- R²
- 0.94
- Method
- Nonlinear seemingly unrelated regression with weight functions; additivity constrained so compartments sum to total
- Where
- Ontario and Quebec, Canada (ENFOR archival data, early 1980s)
- Last checked
- 2026-11-03
Calculate
124
Aboveground biomass (kg)
58.5
Carbon (kg), ×0.47
215
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%.
| Inputs | Expected | We get | From |
|---|---|---|---|
| D = 20 | 124 | 124 | Computed from the printed form computed from the published form at dbh = 20 cm |
Related
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- Canadian national equation, eastern hemlock, dbh and height (sum of wood, bark, branches, foliage; Table 4) · Lambert et al. 2005 · DBH + Height
- Western hemlock total aboveground biomass from DBH and height (Table 4) · Poudel et al. 2019 · DBH + Height
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- Canadian national equation, alpine fir, dbh and height (sum of wood, bark, branches, foliage; Table 4) · same paper · Aboveground biomass
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- Canadian national equation, alpine fir, dbh only (sum of wood, bark, branches, foliage; Table 3) · same paper · Aboveground biomass