# Norway spruce, Czech Republic: Total aboveground biomass from D (Table 2)

Aboveground biomass equation for Picea abies, Czechia, from Čihák & Vejpustková 2018. 139 trees. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Čihák & Vejpustková 2018 (Table 2 and Eq. 2, p. 113 and p. 110):

> AGB = exp(b0 + b1ln(D))λ; b0 = -1.95298, b1 = 2.35768, λ = 0.986

Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#equation

In this library's units, ready to compute (aboveground biomass in kg):

```
Aboveground biomass = exp(-1.95298 + 2.35768 * ln(D)) * 0.986
```

Inputs: D = Diameter at breast height (1.3 m) (cm).
The source's own form: exp(-1.95298 + 2.35768 * ln(D)) * 0.986, with D in cm; output in kg.
Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#canonical

## What it covers

- Output: Aboveground biomass, kg
- Taxon: Picea abies (species), family Pinaceae; conifer
- Where: 25 stands on 15 sites, Czech Republic (acidic and nutrient-medium sites). Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#where
- Biomes: temperate
- Stand: mixed
- Trees measured: 139. Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#n_trees
- R²: 0.95. Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#r2
- Correction factor: 0.986 (applied). Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#cf
- Method: log-log linear regression with Marklund (1987) back-transformation correction factor. Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#checked_at

A missing fit statistic is one the source doesn't state, or that we haven't recorded; it is never estimated. Outside the stated DBH range or region, the equation is an extrapolation.

## Source

Čihák, T., & Vejpustková, M. (2018). Parameterisation of allometric equations for quantifying aboveground biomass of Norway spruce (Picea abies (L.) H. Karst.) in the Czech Republic. Journal of Forest Science, 64(3), 108–117.

- DOI: https://doi.org/10.17221/61/2017-jfs
- Access: open access
- Copy we read: https://www.agriculturejournals.cz/publicFiles/61_2017-JFS.pdf
- Every equation from this source: https://treeallometry.org/sources/cihak-2018/
- Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#source

## The facts, in the source's words

**Equation** (Table 2 and Eq. 2, p. 113 and p. 110):

> AGB = exp(b0 + b1ln(D))λ; b0 = -1.95298, b1 = 2.35768, λ = 0.986

Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#equation

**Trees measured** (Abstract):

> an extensive data set of 139 spruce trees collected in 25 stands on 15 sites

Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#quote-fit-n-trees

**Our note:** Coefficients, R2 and lambda as printed in Table 2 (lambda per Marklund 1987, Eq. 3, already multiplied in). H/D is slenderness ratio, tree height (m) over DBH (cm). Not recommended for trees with D < 7 cm. Table 2 also gives models with site index (SI) or tree age (A) and crown biomass models, not added here (no canonical variable for SI or A; crown has no output quantity).

## Checks this equation passes

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

| Inputs | Expected | We get | From |
| --- | --- | --- | --- |
| D = 10 | 31.9 | 31.9 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 25 | 276 | 276 | Computed from the printed form: computed from the published form (coefficients as printed) |
| D = 45 | 1,105 | 1,105 | Computed from the printed form: computed from the published form (coefficients as printed) |

Cite: https://treeallometry.org/equations/cihak-2018-agb-d/#checks

The calculator on the page shows carbon as biomass × 0.47 (IPCC 2006 Guidelines, Vol. 4, Ch. 4, Table 4.3) and CO₂e as carbon × 44/12.

## How to cite

Cite the source for the equation: Čihák, T., & Vejpustková, M. (2018). Parameterisation of allometric equations for quantifying aboveground biomass of Norway spruce (Picea abies (L.) H. Karst.) in the Czech Republic. Journal of Forest Science, 64(3), 108–117. https://doi.org/10.17221/61/2017-jfs

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Norway spruce, Czech Republic: Total aboveground biomass from D (Table 2)", checked 2026-11-02, https://treeallometry.org/equations/cihak-2018-agb-d/. Data CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Quotes are the authors' words.

Data for this equation: https://treeallometry.org/data/equations/cihak-2018-agb-d.json
Report a problem: email info@restorationscope.com with the equation id (cihak-2018-agb-d) and where the right value appears.