CR prepress abstract  -  doi: 10.3354/cr01465

Drivers of treeline shift in different European mountains

Pavel Cudlin*, Matija Klopcic, Roberto Tognetti, Frantisek Malis, Concepción L. Alados, Peter Bebi, Karsten Grunewald, Miglena Zhiyanski, Vlatko Andonowski, Annika Hofgaard, Nicola La Porta, Tomas Hlasny, Svetla Bratanova-Doncheva, Magda Edwards-Jonášová, Petr Skalák, Josep Maria Ninot, Eli Kachaunova, Andreas Rigling, Frans Emil Wielgolaski

*Email: cudlin.p@czechglobe.cz

ABSTRACT: A growing body of evidence suggests that processes of upward treeline expansion and shifts of vegetation zones may occur in response to climate change. Such shifts can be, however, limited by a variety of non-climatic factors, such as nutrient availability, soil conditions, landscape fragmentation and some species-specific traits. Many changes in species distribution have been observed, though no evidence of complete community replacement has been registered yet. Climatic signals are often confounded with the effects of human activity; for example, forest encroachment at the treeline owing to the coupled effect of climate change and highland pasture abandonment. In this paper, data on the treeline ecotone, barriers of the expected treeline or dominant tree species shifts due to climate and land use change, and their possible impacts on biodiversity in 11 mountain areas of interest, from Italy to Norway and from Spain to Bulgaria, are reported. We investigated the role of environmental conditions on treeline ecotone features with a focus on treeline shift. The results showed that treeline altitude and the altitudinal width of the treeline ecotone, as well as the significance of climatic and soil parameters as barriers against tree species shift, significantly decreased with increasing latitude. However, the largest part of the commonly observed variability in mountain vegetation near the treeline in Europe seems to be caused by geomorphological, geological, pedological and microclimatic variability in combination with different land use history and present socio-economic relations.