The forest has many functions: It supplies the renewable raw material of wood, protects humans against natural disasters and provides a habitat for numerous plants and animals. It plays an important role in protecting drinking water and as a carbon sink. In addition, it creates jobs through wood harvesting and processing, and provides an important recreational area for the population. To be able to fulfil its many different functions, a forest requires a sufficiently large forest area with as little fragmentation as possible.
Around one-third of Switzerland is covered by forest. Overall, Switzerland’s forest area has been growing for 150 years. As far as the most recent decades are concerned, the forest area grew by 3.4% from 1986 to 1995, by 4.6% from 1996 to 2006, and by 2.3% from 2007 to 2013. This positive development reflects the success of the forest legislation. To date, its aim has been to better protect the population against natural hazards and secure the wood supply. However, new objectives like biodiversity promotion and recreational use of forests have been added. There are considerable differences in the development of the forest area in the Jura, Central Plateau, Pre-Alps, Alps, Southern Alps regions: In the Central Plateau, the forest is under pressure due to settlement development and infrastructure construction. In contrast, the forest area is growing in unfavourable mountain regions where agricultural activities are frequently abandoned. In recent years, forest ingrowth through natural regeneration has occurred almost exclusively at altitudes over 1,000 metres above sea level in the Alps region and the Southern Alps.
If more important public interests are not affected, as far as forest functions are concerned, there is no reason to stop the forest from spreading. Protection against natural hazards in the mountains could even be improved in this way. However, the future development should be better coordinated with regional spatial planning concerns. Some well-founded reservations do exist when it comes to variables such as landscape aesthetics and biodiversity. In accordance with the revision of the Forest Act of 16 March 2012, the cantons may designate areas in their structural plans where they want to prevent forest growth. On this basis, they can determine static forest boundaries in relation to open land.
The indicator is used in the context of the Ministerial Conference for the Protection of Forests in Europe (Forest Europe) and is therefore comparable throughout Europe. However, when comparing different countries, it should be noted that there is no standard definition of forest. Forest area development at the global level shows contradictory trends: The growth of the forest area in some European countries contrasts with the destruction of the tropical rainforest. Our neighbouring countries have the following percentages of forest area: Germany 32%, Austria 47%, France 29%, Italy 31% and the Principality of Liechtenstein 43%. In comparison, the proportion of forest area in Switzerland is 32%.
The data on forest area and its development are provided by aerial images, the continuous sample survey carried out in forests and subsequent modelling.