In 1993, the Directorate for Nature Management (DN) established a new area for the monitoring of terrestrial ecosystems in Dividalen National Park in Troms County. This report presents the reanalysis of vegetation and soil from this terrestrial monitoring area. The area in Dividalen is located in the northern boreal birch forest, in a relatively continental section where the dominant type of vegetation is bilberry-mountain crowberry birch forest (A4c). The structure of the vegetation is analysed by multivariate methods (ordination). In Dividalen all together 131 species were found; 75 vascular plants, 18 mosses, 14 liverworts and 24 lichens. This is a decrease from the number of species recorded in 1993 when 141 species were found in the same mesoplots: 74 vascular plants, 24 mosses, 18 liverworts and 25 lichens. The decrease was not significant for the total number of species or for the total number of vascular plants. However the total number of cryptogames showed a slight significant decrease in number between 1993 and 1998. This may be due to increased cover of several ericoid species. In Dividalen we found no significant changes in vegetation composition for the periode 1993 – 1998 along the first four ordination axes. However, there were changes in mesoplots with high DCA1 values. The changes were in the direction towards lower species richness. Species like Myosotis decumbens, Poa alpina, Solidago virgaurea, Cerastium fontanum and Rumex acetosa ssp. lapponicus showed the largest decrease in these mesoplots. Species that showed the largest increase were Vaccinium vitis-idaea, Mnium spinosum and Polytrichum juniperinum. We have found no relations between these changes and acidification due to deposition of pollutans. Lack of disturbance factors in the area in the last years, which favours an increase in ericoid vegetation, is the probable explanation for the changes.
The concept for vegetation investigation applied in TOV is harmonised with other vegetation monitoring programmes in Norway and Europe (e.g. Nordic Council of Ministers 2000).