ISO 13391-2:2025
(Main)Wood and wood-based products — Greenhouse gas dynamics — Part 2: Forest carbon balance
Wood and wood-based products — Greenhouse gas dynamics — Part 2: Forest carbon balance
This document provides a methodology for calculating the carbon balance of (a) forest management unit(s) (FMU). This quantification methodology is intended to demonstrate to what extent carbon pools in the FMU represent a net greenhouse gas sink or a net greenhouse gas source. This document provides information that can be used on organizational or aggregated product levels. This calculation methodology considers: — the geographical scale of the FMU; — forest management practices; — land ownership arrangements; — time periods; — the use of forest inventory data and other data sources for determining the forest carbon balance; and — allocation of forest carbon balance to wood that has been sourced in FMU(s). Greenhouse gas emissions from fossil fuels or industrial processes related to forestry operations (e.g. production and distribution of fertilizers, fuels for machinery) are not included in this document. NOTE 1 Greenhouse gas emissions related to forestry operations are covered in ISO 13391-1. The quantity of wood entering the harvested wood products carbon pool is not included in this document. NOTE 2 Material entering the harvested wood products carbon pool is calculated in ISO 13391-1. This document is intended to be used by organizations seeking to understand, commit to or contribute to climate change mitigation. These organizations can be either private or public, regardless of type or size, and located in any jurisdiction or any position within a specific value chain.
Produits en bois et dérivés du bois — Dynamique des gaz à effet de serre — Partie 2: Bilan carbone des forêts
General Information
Standards Content (Sample)
International
Standard
ISO 13391-2
First edition
Wood and wood-based products —
2025-04
Greenhouse gas dynamics —
Part 2:
Forest carbon balance
Produits en bois et dérivés du bois — Dynamique des gaz à effet
de serre —
Partie 2: Bilan carbone des forêts
Reference number
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Contents Page
Foreword .iv
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Methodology for calculating the forest carbon balance . 3
4.1 General requirements .3
4.2 System boundaries . .4
4.3 Characterization of the FMU(s) by the organization .4
4.4 FMUs and land ownership .4
4.5 Geographical scale .5
4.6 Time periods . .5
4.7 Greenhouse gas emissions and removals in the FMU .6
4.7.1 General .6
4.7.2 Tiered approach .8
4.7.3 Tier approach for living biomass above ground .8
4.8 Data sources .8
4.8.1 General .8
4.8.2 Time series data .9
4.9 Data quality .9
4.10 Calculating changes in FMU carbon pools .9
4.10.1 General .9
4.10.2 Stock change methodologies . . . 12
Annex A (informative) Specific guidance for the five carbon pools .13
Bibliography . 14
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