Switzerland's forests protect against natural hazards, filter drinking water, provide a habitat for a wide variety of species, offer space for recreation, store CO2 and deliver raw materials for climate-friendly technologies. Their diversity of tree species and structures has been growing for decades now, improving resilience to the effects of climate change. The impact of climate change varies from region to region. Drought, heat, storms, pests and the confluence of these factors are increasingly damaging the health of the forests and diminishing their benefits as a life-sustaining natural resource.
- 1. Traffic, agriculture, climate change, demand for wood, society’s demands (drivers)
- 2. Drought, pest infestation, nitrogen and air pollutants, insufficient management, recreation (pressures)
- 3. Forest area increase, wood harvesting potential under-exploited, healthy living environment (state)
- 4. Less stability, change in forest biodiversity, CO2 sinks (impacts)
- 5. Deforestation ban, forest protection and sustainable forest management, forest reserves, adaptation to climate change (responses)
1. Drivers: Climate change, pollutants, global trade in goods
Temperatures in Switzerland between 2011 and 2020 were already 2.5 °C warmer on average than in pre-industrial times. If efforts to significantly cut global greenhouse gases are unsuccessful, further warming of a good 2 to 4 °C can be expected by 2100. As the climate warms, dry periods and other extreme weather events will become more common. Trees will be weakened and the risk of forest fires will also rise.
An additional factor affecting the health and resilience of the forest is the input of pollutants and in particular the input of nitrogen into the forest. In addition, there is a strong increase in invasive alien species due to the global trade in goods, which has a negative impact on forest biodiversity and forest health.
2. Pressures: Extreme events, pest infestations and diseases
The hot, dry summers of 2015, 2018 and 2019 significantly damaged the health of Swiss forests in some regions. Trees lost their leaves or needles too early, were weakened by weather extremes or even died off. Climate change means that many tree species will cease to be viable in their current locations. Targeted intervention is now needed to promote tree species that can cope with the climate of the future and thus enable forest ecosystems to adapt to rapidly changing conditions.
Dry periods and storms produce large volumes of damaged and infested timber. Such damaging events are likely to become more frequent and more widespread as the climate changes. If large volumes of timber accrue across entire regions simultaneously, it will not be possible to process all of the resulting oversupply. This depresses timber prices and the forestry industry will face increasing financial difficulties with its forest management activities.
The forest is also increasingly threatened by harmful organisms. These include the bark beetle or invasive alien fungal diseases such as Hymenoscyphus fraxineus and red-band disease in pines, which are increasingly attacking the forest. The spread of invasive alien plants (e.g. tree of heaven) is also increasing. Forests that are difficult to access in the Alps and Pre-Alps are often insufficiently managed. As a result, an adverse age structure develops and, as a result, the forests are no longer able to fulfil all of their functions.
3. State: Forest area, tree species diversity, biodiversity
In Switzerland, 31% of the land area is covered with forest. According to forestry statistics, Switzerland's total forest area covered 1,268,383 ha in 2020. Forest area at higher altitudes and on the southern side of the Alps has increased slightly over the past decade, but has remained constant in lower-lying areas.
There is a positive trend in the diversity of domestic tree species and structured forests, and volumes of dead wood are rising. These are decisive elements for a flourishing forest biodiversity. However, there are some regional disparities, with deficits still in the Jura and the Central Plateau.
The effect of nitrogen inputs from farming in particular, as well as from transport, is that trees weaken because root growth, and therefore stability, are not as strong as they should be. Nitrogen-loving plants such as blackberries are getting out of hand in many areas, making it more difficult to care for forest land and obstructing its rejuvenation.
4. Impact: Multifunctional ecosystem, wood use, climate protection
As multifunctional ecosystems,forests provide essential services. They produce timber, an important raw material, protect against natural hazards, ensure healthy soils and thus have a positive effect on drinking water supplies, store CO2, provide space for recreation and have a cooling effect on settlement areas during hot weather. Yet the forests are under increasing pressure from climate change, a combination of stress factors (drought, pollutants and harmful organisms) and the changing demands of society in terms of leisure activities.
Intervention is urgently needed – for the timber harvest, to rejuvenate ageing protection forests and to promote species diversity – to ensure that forest ecosystems can continue to fulfil their various functions. However, timber revenues alone are not enough to cover the costs of this action, which benefits the public. Forest management has been abandoned in some places, especially in the Alps and Alpine foothills. More and more timber is being left unfelled, and protection forests are becoming less stable. This means that much of the potential contained in targeted support for forest functions remains untapped, especially where the use of wood as a resource and as a factor in climate action are concerned.
Climate change is also altering the composition of tree species in Switzerland's forests. In the lowlands the percentage of hardwoods will increase. Timber use traditionally focuses heavily on coniferous species. The increasing share of hardwoods therefore requires new utilisation options.
5. Responses: Forest Policy and Wood Resource Policy with action plan
Based on the Federal Constitution, the object of the Forest Act is to safeguard the protective, social and economic functions of forests, both now and in the future under different climatic conditions. The federal government and the cantons ensure that the forest area is conserved, protect forests as natural habitats, and promote the forestry sector.
In its Forest Policy the federal government sets out its objectives for the future of Swiss forests, and balances the ecological, economic and social demands that they must satisfy. In this context, sustainable forest management ensures that forests are able to perform their protective service, supports biodiversity, prepares forests for climate change, improves the quality of the landscape and helps to mitigate the effects of a warming atmosphere. The federal government also creates favourable conditions for an efficient and innovative forest and wood industry. The forest policy is thus in line with the goals of the UN 2030 Agenda for Sustainable Development.
The Wood Resource Policy sets out a vision in which wood is a characteristic component of architecture and interior design and has a positive impact on quality of life. The federal government would like to see more use made of wood from Swiss forests. To ensure that wood and wood products can be sustainably provided, processed and utilised in line with demand, it wants to strengthen the competitiveness and innovative power of the forest and wood value chain. The updated Wood Action Plan highlights the benefits of wood as a material and commodity in an effort to clear the way towards better value creation.
These policies are reflected in specific measures on the following topics:
- Promotion of resilient and multifunctional forests through proactive silvicultural measures
- Preservation of the forest area in its current spatial distribution; this will become even more important in the future in view of growing competing spatial demands (settlement, recreation, infrastructures, flood defences)
- Conservation and promotion of biodiversity in the forest
- Financing of forestry interventions to secure the ecosystem services of the forest in the long term (e.g. protection, recreation, climate protection, water filtration)
- Preservation of forest health and measures to improvement management of events
- Exploitation of the untapped potential of Swiss wood for increased use as a building material, a chemical raw material and, to a lesser extent, a source of energy.
Last modification 20.12.2022