Link zu WSL Hauptseite Swiss Federal Institute for Forest, Snow and Landscape Research WSL
Duration: 2013 - 2014


Old beech tree at the study site Vétroz, VS, Switzerland
Picture: Pascale Weber (WSL)

Under the predicted climatic changes, forest ecosystems are expected to change in their structure and species composition. Unmanaged forests are of exceptional value, because they allow us to study natural forest dynamics and compare it to dynamics under forest management where competition for light between single trees is changed deliberately. Such comparisons will help at adapting better the forest management to climatic changes. For a long time, the general age-related decline of tree growth, typical for the managed forest, has been assumed to be realistic for the natural forest, too. However, in recent years, a few studies have shown disagreement between the general sigmoid model and real measurements of tree growth. Thus, we propose to analyze individual growth patterns to gain a deeper insight into the life history and longevity of trees. We will explore several methods that have been developed to detect growth releases and suppression and develop a new method based on tree-ring trends. With this combination of methods we aim to compare the growth patterns of spruce and beech trees from natural forests in the Ukraine and Bosnia with those from managed forests in Switzerland (cf. projects CASTS and KABIM). We hypothesize that multiple release/suppression periods and bimodal growth patterns are typical for uneven-aged forest structures with a small gap disturbance dynamic, while slow decreases in tree growth are typical for even-aged forests.

The project is funded through Sciex.

Project team


Volodymyr Trotsiuk

David Frank

Keywords Detrending splines, dendroecology, dendrochronology, tree-rings, life history, age, release/suppression, Fagus sylvatica, Picea abies