# Gray alder, southern taiga and mixed-forest data (Kazimirov 1978, Miezīte 2011): root biomass from D and aboveground biomass (Table 2)

Root biomass equation for Alnus incana, Russia, Latvia, from Karaban et al. 2023. 17 trees. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Karaban et al. 2023 (Table 2, ln Pr row, eq. (3)):

> ln Pr (3) 2,1294 –3,5935 2,4672 – 0,945 0,265 17 (ln Pr = a0 + a1 ln D + a3 ln Pa)

Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#equation

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

```
Root biomass = exp(2.1294 + -3.5935 * ln(D) + 2.4672 * ln(AGB))
```

Inputs: D = Diameter at breast height (1.3 m) (cm); AGB = Aboveground dry biomass of the tree (kg).
The source's own form: exp(2.1294 + -3.5935 * ln(D) + 2.4672 * ln(Pa)), with D in cm, Pa in kg; output in kg.
Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#canonical

## What it covers

- Output: Root biomass, kg
- Taxon: Alnus incana (species), family Betulaceae; broadleaf
- Where: Southern taiga and coniferous-broadleaved subzones of European Russia and Latvia (root data of Kazimirov et al. 1978 and Miezīte et al. 2011), not the Arkhangelsk sample. Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#where
- Biomes: boreal, temperate
- Stand: mixed
- Trees measured: 17. Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#n_trees
- Residual SE: 0.265. Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#rse
- Method: OLS regression on natural logarithms; free term corrected for log transformation (Baskerville 1972). Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#method
- Verification: read in the original source
- Last checked: 2026-11-02. Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#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

Karaban, A. A., Usoltsev, V. A., Tretyakov, S. V., Koptev, S. V., Paramonov, A. A., Tsvetkov, I. V., Davydov, A. V., & Tsepordey, I. S. (2023). Biomass of gray alder trees and its allometric models in the conditions of the Arkhangelsk region. Forests of Russia and economy in them, 2(85), 42–50.

- DOI: https://doi.org/10.51318/fret.2023.36.20.005
- Access: open access
- Copy we read: https://usfeu.ru/media/filer_public/31/1c/311c8894-375c-49bb-9c23-860c9d9a5c51/5_karaban_usoltsev_dr_biomassa_derevev_olkhi.pdf
- Every equation from this source: https://treeallometry.org/sources/karaban-2023/
- Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#source

## The facts, in the source's words

**Equation** (Table 2, ln Pr row, eq. (3)):

> ln Pr (3) 2,1294 –3,5935 2,4672 – 0,945 0,265 17 (ln Pr = a0 + a1 ln D + a3 ln Pa)

Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#equation

**Trees measured** (Results, p. 46 (root data from Kazimirov et al. 1978 and Miezite et al. 2011, southern taiga and mixed forest subzones)):

> 17 определений

Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#quote-fit-n-trees

**Our note:** Root biomass was not measured by the authors: fitted on 17 observations for gray alder from the southern taiga and coniferous-broadleaved subzones (Kazimirov et al. 1978; Miezite et al. 2011), not on the Arkhangelsk trees. Inputs: D in cm and aboveground biomass Pa in kg (Pa = AGB). adjR2 = 0.945. Natural log as printed; Baskerville correction already in the free term.

## 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 = 5, AGB = 5 | 1.37 | 1.37 | Computed from the printed form: computed from the published form (coefficients as printed; free term already includes the Baskerville log correction per the Table 2 note) |
| D = 10, AGB = 20 | 3.48 | 3.48 | Computed from the printed form: computed from the published form (coefficients as printed; free term already includes the Baskerville log correction per the Table 2 note) |
| D = 15, AGB = 45 | 5.99 | 5.99 | Computed from the printed form: computed from the published form (coefficients as printed; free term already includes the Baskerville log correction per the Table 2 note) |

Cite: https://treeallometry.org/equations/karaban-2023-bgb-d-agb/#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: Karaban, A. A., Usoltsev, V. A., Tretyakov, S. V., Koptev, S. V., Paramonov, A. A., Tsvetkov, I. V., Davydov, A. V., & Tsepordey, I. S. (2023). Biomass of gray alder trees and its allometric models in the conditions of the Arkhangelsk region. Forests of Russia and economy in them, 2(85), 42–50. https://doi.org/10.51318/fret.2023.36.20.005

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Gray alder, southern taiga and mixed-forest data (Kazimirov 1978, Miezīte 2011): root biomass from D and aboveground biomass (Table 2)", checked 2026-11-02, https://treeallometry.org/equations/karaban-2023-bgb-d-agb/. 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/karaban-2023-bgb-d-agb.json
Report a problem: email info@restorationscope.com with the equation id (karaban-2023-bgb-d-agb) and where the right value appears.