# Root-to-shoot ratio, Tropical rainforest forest, Africa (natural, AGB ≤ 125 t/ha)

Root:shoot ratio (default value) for Tropical rainforest forest trees, Africa; Tropical rainforest ecological zone (FAO 2015 Global Ecological Zones), from Domke et al. 2019. Listed on Tree Allometrics, a free library of tree allometric equations, each quoted from the source that published it.

## Equation

As printed in Domke et al. 2019 (Table 4.4 (Updated), p. 4.18):

> Tropical rainforest | Africa | Natural ≤ 125 0.825 ±90% default 1, 2

Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#equation

In this library's units, ready to compute:

```
Root:shoot ratio = 0.825
```

No inputs: a constant.
The source's own form: 0.825; output unitless.
Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#canonical

## What it covers

- Output: Root:shoot ratio
- Taxon: Tropical rainforest forest trees (mixed species); mixed
- Where: Africa; Tropical rainforest ecological zone (FAO 2015 Global Ecological Zones). Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#where
- Biomes: tropical
- Stand: natural
- Verification: read in the original source
- Last checked: 2026-11-01. Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#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

Domke, G., Brandon, A., Diaz-Lasco, R., et al. (2019). Chapter 4: Forest Land. In: 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Volume 4: Agriculture, Forestry and Other Land Use. IPCC.

- Link: https://www.ipcc-nggip.iges.or.jp/public/2019rf/vol4.html
- Access: open access
- Copy we read: https://www.ipcc-nggip.iges.or.jp/public/2019rf/pdf/4_Volume4/19R_V4_Ch04_Forest%20Land.pdf
- Every equation from this source: https://treeallometry.org/sources/ipcc-2019-v4-ch4/
- Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#source

## The facts, in the source's words

**Equation** (Table 4.4 (Updated), p. 4.18):

> Tropical rainforest | Africa | Natural ≤ 125 0.825 ±90% default 1, 2

Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#equation

**Output** (Table 4.4 (Updated) title, p. 4.18):

> RATIO OF BELOW-GROUND BIOMASS TO ABOVE-GROUND BIOMASS (R) [TONNE ROOT D.M. (TONNE SHOOT D.M.)-1]

Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#quote-output

**Our note:** IPCC Tier 1 default R (root d.m. / shoot d.m.). Applies to stands with above-ground biomass ≤ 125 tonnes/ha: the threshold is stand-level (t/ha), not tree AGB, so it cannot be expressed in the tree-level expression. Uncertainty ±90%, default. Table references: 1, 2 (12 = Mokany et al. 2006). Multiply tree AGB by R to estimate BGB.

## 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 |
| --- | --- | --- | --- |
| AGB = 500 | 0.825 | 0.825 | Value printed in the paper: constant ratio printed in Table 4.4 (Updated), p. 4.18; independent of tree AGB |

Cite: https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/#checks

## How to cite

Cite the source for the equation: Domke, G., Brandon, A., Diaz-Lasco, R., et al. (2019). Chapter 4: Forest Land. In: 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Volume 4: Agriculture, Forestry and Other Land Use. IPCC.

Cite this page for the record and checks: Tree Allometrics (Restoration Scope), "Root-to-shoot ratio, Tropical rainforest forest, Africa (natural, AGB ≤ 125 t/ha)", checked 2026-11-01, https://treeallometry.org/equations/ipcc-2019-v4-ch4-rs-rainforest-africa-le125/. 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/ipcc-2019-v4-ch4-rs-rainforest-africa-le125.json
Report a problem: email info@restorationscope.com with the equation id (ipcc-2019-v4-ch4-rs-rainforest-africa-le125) and where the right value appears.