Tree Allometrics

Equations / Total biomass

Cryptomeria japonica Total (above + below) from DBH (Table 3)

Total biomassCryptomeria japonica · CupressaceaeSouth KoreaplantationRead from the original paper
Photo of Cryptomeria japonica
© Marco Mussita · CC BY · iNaturalist
Equation

As printed (Materials and Methods, Data analysis)

Y = exp [a + b*ln(X)]

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

Total biomass = 1.0 * exp(-1.777 + 2.169 * ln(D))
D
Diameter at breast height (1.3 m), cm

Y = CF * exp[a + b*ln(X)], Y in kg, X = DBH in cm; the Sprugel correction factor CF = exp(SEE^2/2) from Table 3 is applied (text: Sprugel correction factors were used to correct the bias). Includes root. Table 3 prints no n per equation; n = 18 harvested sample trees (roots of all 18 reported in Table 2). Single 40-year-old stand.

Source
Total -1.777 2.169 0.116 0.953 1.000
Equation · Table 3 (columns a, b, RMSE, R2, CF)
A total of 18 representative sample trees were selected based on their DBH class.
Trees measured · Data collection
DBH (cm) 20 (13-28)
Smallest DBH · Table 1
Trees measured
18
DBH range
13–28 cm
Height range
9–14 m
R²
0.953
Correction factor
1 (applied)
Method
log-log regression with Sprugel correction factor (SAS 9.1)
Where
Hannam experimental forest, Mount Halla, Jeju Island, South Korea
Last checked
2026-11-02
Calculate
60.15
Total biomass (kg)
28.27
Carbon (kg), ×0.47
103.7
CO₂e (kg), ×44/12
Fitted DBH range0100200300400500600510152025303540DBH (cm)Total biomass (kg)Total 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 = 1560.160.1Computed from the printed form
computed from the Table 3 coefficients and CF
D = 25182.1182.1Computed from the printed form
computed from the Table 3 coefficients and CF

Report a problem with this equation · JSON

Related