Mountain Vegetation in Transition : Effects of Time, Compass Direction, and Altitude

Mountain vegetation has undergone notable changes over recent decades. The alpine vegetation is particularly sensitive to disturbances because of long recovery times, due to, harsh climate conditions and short growing seasons. In the Swedish mountains a change of elevation of the treeline has been observed which can lead to establishment of new species higher in the mountain area. These species may compete with native alpine species, potentially leading to alterations in vegetation cover. The underlying cause of this could be climate change, land use and tourism or a combination of these. This study aims to investigate the changes in vegetation in the Swedish mountain regions with a focus on cover of the functional groups: dwarf shrubs, forbs, mosses, fruticose lichens and reindeer lichens, along with reindeer lichen height. An analysis was conducted using a linear mixed model and showed effects of time, compass direction and altitude. Significant differences for some of the factors were found in all groups, while some factors showed no differences. The findings indicated that certain changes had taken place in the mountain vegetation.