Forest management and forest reserves

According to the Objectives of Swiss Forest Reserve Policy, the Confederation aims to place 10 per cent of this country’s woodlands under contractually agreed protection as forest reserves. The intention is to declare one half as natural forest reserves without any interventions and the other half as special forest reserves involving concerted cultivation measures. This 10 per cent forest reserve goal is the object of a motion tabled by Sylvia Flückiger-Bäni (10.3124). Research results of the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) are able to contribute towards the clarification of facts in this connection.

At present, approximately 3.5 per cent of Switzerland’s woodlands are protected as forest reserves. Their exact situations have not been documented nationwide to date. To determine forest management objectives in terms of surface, the National Forest Inventory (NFI) therefore takes its bearings from the functions that woodlands fulfil: in the context of the NFI, local foresters were asked what function of a forest would constitute the determinant factor for any interventions in a situation of conflict (priority function). As replies revealed, the primary – but not exclusive – function of 7 per cent of the entire wooded surface is to serve nature conservation purposes. These are classed as nature conservation forests by the NFI. In the Jura, they amount to 10 per cent of all the woodlands, in the Midlands to 8 per cent, in the pre-Alpine regions to 8 per cent, in the Alps to 6 per cent and on the south side of the Alps to 5 per cent.

Considerable parts of nature conservation forests are commercially used

In such nature conservation forests, the annual wood increment per hectare is slightly lower than that of the average of all woodlands: although the nature conservation forests amount to 7 per cent of the wooded surface, they only generate 6 per cent of the entire wood increment. Just under three quarters of the increment produced by the entire wooded surface is used for forestal purposes, as opposed to about half of the increment of nature conservation forests. However, 20 per cent of the increment produced by all the woodlands is lost through tree mortality. Dead trees can only be used in part. If logging is not to exceed increments, then almost eight times as much timber remains unexploited outside nature conservation forests as inside them. Even if the set objectives of turning 10 per cent of Switzerland’s woodlands into reserves were achieved, only a small amount of exploitable timber would be lost. In all the other forests, wood also remains unexploited, for instance for economic reasons when a forest is on a steep slope or when accessibility is poor. However, poor accessibility is more frequent in nature conservation forests. In addition, private forest owners, in particular, make use of their right not to exploit their woods.

Unexploited woods usually do not serve nature conservation

About 17 per cent of all Swiss forests have not been exploited for more than 50 years. In the Jura, this amounts to 4 per cent, in the Midlands to 2 per cent, in the pre-Alpine regions to 10 per cent, in the Alps to 25 per cent and on the south side of the Alps to 57 per cent. Among the nature conservation forests, the proportion of woods that have remained unexploited for more than 50 years amounts to 27 per cent. Conversely, only 11 per cent of woodlands that have not been exploited for a long time are nature conservation forests: according to the information provided by local foresters, the largest part serves priority functions other than nature conservation.

Wood reserves are also necessary in low-lying areas

Most inaccessible and unexploited forests are located in the mountains. Protection, however, is also needed by animals, plants and other organisms that are confined to low-lying areas – no matter whether in the form of a decision to relinquish exploitation or of a specific form of cultivation, for example in favour of less dense forest structures. Thus if the Swiss forest reserve policy pursues the long-term aim of securing representatives of all the forest types that are as close to their natural status as possible, then the woodlands that have remained unexploited for the last 50 years alone will not suffice.

Woodlands per se do not constitute a CO₂ sink
The wording of the motion also refers to the carbon footprint of wood as a raw material. According to the Kyoto Protocol, the carbon footprint of Swiss woodlands fluctuates a great deal from year to year. It is influenced by logging volumes and, above all, by large-scale damage caused by events such as storms. We are therefore unable to rely on woodlands constituting a safe CO₂ sink. Depending on weather conditions, exploitation and mortality, forests may even be a source of CO₂.