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About a third of Switzerland is covered by forest, which is one of the hallmarks of our landscape and enhances our quality of life. We are studying this complex ecosystem to find appropriate ways in which people can use and protect the forest.


Forests offer protection against natural hazards such as rockfalls and avalanches, filter our drinking water and prevent soil erosion. They provide wood, store carbon, and serve as recreational spaces for people, habitats for flora and fauna, and havens of biodiversity.

Impact of climate change and natural events

Threats to the above-mentioned forest functions are mounting as a result of the worldwide upheavals in the climate system and in society: what impact do climate change, loss of biodiversity, invasive species and productivity levels in timber production have on our forests? What happens with nutrient cycles, carbon storage, the resistance of the forests to pests, and the services which are of consequence to mankind?

Timber utilisation, forest preservation and soil protection

We are exploring these issues as part of our research. Our focus is on the sustainable exploitation of forest resources, which maintains and supports the functions and adaptability of the forest. Several long-term forest monitoring projects and experimental plots, some of which we have operated for more than 100 years, provide data series documenting the condition and usage of Swiss forests. They also facilitate an understanding of how soil, water, air and climate, pollutants and disturbances, such as storms and forest fires, interact with the forest ecosystem.

A look ahead

We want to take a look at the possible future of the forests, and this requires broad-based research including long-term observations, information from annual tree-ring data which reach far into the past, laboratory and field experiments, computer modelling, and in-depth knowledge of management practices. We combine all these approaches under one roof, using state-of-the-art environmental research techniques, such as isotope analysis, for which we operate a separate isotope laboratory.

As one of the world's leading forest research institutes, we participate in numerous European and international research networks such as the Long-Term Ecosystem Research (LTER) Network in Europe. We coordinate a network of leading Swiss forest researchers from various disciplines as part of our strategic initiative SwissForestLab, so that these researchers can join forces in addressing the most important research questions.

And last but not least, as a federal institute, we also perform the task of imparting our knowledge to forestry practitioners and nature conservationists in the form of recommendations, leaflets and continuing education.



Forest protection Switzerland

The specialist unit for forest protection issues at the WSL.

Forests and climate change

Climate change will drastically alter the Swiss forests, with consequences for humans. WSL conducts research into the relevant processes.

Forest development and monitoring

Long-term environmental observation detects gradual changes, including climate effects and the input of pollutants.

Forest management and forest functions

How does forest develop, and how can we use it without affecting its essential processes and services?

Soil and cycles

We monitor and measure how environmental influences alter the living conditions in the forest soil and study the processes that occur in root areas.

Diseases, pests and disturbances

Damage caused by insects, pathogenic agents, storms and forest fires all devastate forests. We investigate how the forest reacts to these phenomena.

Tree-ring research

Trees react to their environment. At WSL, tree-ring scientists date and analyze these natural archives.



By supplying pine trees with labelled CO2, researchers have shown for the first time how sugars formed by trees are distributed in the soil.

What is Vapor Pressure Deficit and why does it matter for forests? A SwissForestLab video presents high-end research in this field.

Der Schwefelkäfer (Cteniopus sulphureus) ernährt sich von Pollen verschiedener Pflanzen. Foto: Felix Neff / WSL

Where plant diversity declines due to land use, there are fewer insects and biodiversity decreases, indicates a large study led by WSL.

Tree buds emerge from dormancy when they have been exposed to cool temperatures for a certain time.




Durch den Klimawandel wird es wärmer und extreme Trockenheitsperioden werden häufiger. Deshalb steigt das Waldbrandrisiko. Mit einem umfassenden Wissen zur Feuerökologie kann besser abgeschätzt werden, ob Schutzleistungen erhalten bleiben oder waldbauliche Massnahmen zu treffen sind.

Merkblatt für die Praxis 65

Fristoe, T.S.; Chytrý, M.; Dawson, W.; Essl, F.; Heleno, R.; Kreft, H.; Maurel, N.; Pergl, J.; Pyšek, P.; Seebens, H.; Boch, S.; Van Kleunen, M., 2021: Dimensions of invasiveness: links between local abundance, geographic range size, and habitat breadth in Europe's alien and native floras. Proceedings of the National Academy of Sciences of the United States of America PNAS, 118, 22: e2021173118 (11 pp.). doi: 10.1073/pnas.2021173118

Neff, F.; Brändle, M.; Ambarlı, D.; Ammer, C.; Bauhus, J.; Boch, S.; Hölzel, N.; Klaus, V.H.; Kleinebecker, T.; Prati, D.; Schall, P.; Schäfer, D.; Schulze, E.; Seibold, S.; Simons, N.K.; Weisser, W.W.; Pellissier, L.; Gossner, M.M., 2021: Changes in plant-herbivore network structure and robustness along land-use intensity gradients in grasslands and forests. Science Advances, 7, 20: eabf3985 (13 pp.). doi: 10.1126/sciadv.abf3985

Večeřa, M.; Axmanová, I.; Padullés Cubino, J.; Lososová, Z.; Divíšek, J.; Knollová, I.; Aćić, S.; Biurrun, I.; Boch, S.; Bonari, G.; Campos, J.A.; Čarni, A.; Carranza, M.L.; Casella, L.; Chiarucci, A.; Ćušterevska, R.; Delbosc, P.; Dengler, J.; Fernández‐González, F.; ... Chytrý, M., 2021: Mapping species richness of plant families in European vegetation. Journal of Vegetation Science, 32, 3: e13035 (17 pp.). doi: 10.1111/jvs.13035

Boch, S.; Martins, A.; Sim-Sim, M.; Bergamini, A., 2021: Effects of elevation and disturbances on the associations between the diversities of bryophyte and macrolichen functional-taxonomic groups on Madeira Island. Bryologist, 124, 2: 178-190. doi: 10.1639/0007-2745-124.2.178

Gao, D.; Joseph, J.; Werner, R.A.; Brunner, I.; Zürcher, A.; Hug, C.; Wang, A.; Zhao, C.; Bai, E.; Meusburger, K.; Gessler, A.; Hagedorn, F., 2021: Drought alters the carbon footprint of trees in soils—tracking the spatio-temporal fate of 13C-labelled assimilates in the soil of an old-growth pine forest. Global Change Biology, 27: 2491-2506. doi: 10.1111/gcb.15557