2. Sources, Reference Standards, and Modules

The method presented here is the update of the two methods "Method for Climate Protection Projects in Forests for Switzerland, according to ISO 14064-2 with external certification 2019" and "SILVACONSULT® Forest Carbon Standard, according to ISO 14064-2 with external certification 2022".

2.1 Normative Foundations

This methodology is based on the standard 14064-2:2019 (Ref. 03) and uses its terminology. ISO 14064-2 is a standard for the "Specification with guidance at the project level for quantification, monitoring and reporting of greenhouse gas emission reductions or removal enhancements" including. Validation and verification. The provisions of the standard are supplemented in this methodology by using elements of the AR-AMS0001 methodology (Ref. 12) for the quantification of the CDM-Additionality Tool (Ref. 21), to check the Additionality as well as considering the risk determination according to (Ref. 29). This comprehensively represents the aspects of good professional practice. In addition to the principles of relevance, completeness, consistency, accuracy, transparency, conservatism is important. This states that the accountable sink performance must not be overestimated. Soil carbon accounts for more than half of the total carbon in forest on normal sites (Ref. 10, 27, 51, 52). Soil carbon is aligned with the biomass stock of the trees, but it responds slowly to stock changes and is not easily measurable at the project level. It is therefore conservatively not accounted for (Ref. 66).

2.2. Scientific Foundations

In the model of the sustainably managed forest, an equilibrium reserve of wood (normal reserve) establishes itself over larger areas. It is common practice to aim for the "Normal Forest". Growth and utilisation balance each other out. Mortality is negligible in the normal forest model (Ref. 07, 08, 09). The growth rate depends on the natural site. The forest sites are, among others. defined by potentially natural forest communities (Ref. 19). There is no utilisation in the natural forest. The trees there become significantly older and eventually die. A balance of wood stock is also established in the natural forest. This too is dynamic, with growth and decay balancing each other. According to Ref. 14, the average standing wood stock in the natural forest of temperate zones is about twice as high as in sustainably managed forests. Ref. 14 refers to the montane beech-fir-spruce forest of the temperate zone, one of the most common forest communities in Central Europe. Ref. 25 shows that this also applies to other forest communities.

The "Normal Forest Model" is an idealised model of forest structure, where all ages are represented with equal areas. Scientific yield tables are based on this model (Ref. 07, 08).

Utilisation determines the dynamics of the forest carbon storage. If more is used than grows, the average reserve decreases, if less is used, the average reserve increases. From a certain height of reserve, natural mortality increases and the reserve approaches equilibrium in the natural forest.

Forest owners control the development of biomass reserves in the forest through the intensity of wood utilisation relative to growth. By partially refraining from utilisation in the managed forest, the reserve and thus the carbon storage is increased or secured. In the case of a natural forest reserve (set-aside area, forest reserve, protected forest, refuge, old-growth island, etc.), forest owners completely refrain from wood utilisation.