Effects of reindeer density on vascular plant diversity on North Scandinavian mountains

Abstract

Abstract:We studied the effects of reindeer grazing on species richness and diversity of vascular plants on dolomite influenced low alpine sites in the species rich northern part of the Scandes using 8 sites with different reindeer densities. Two sites were situated inside Malla Strict Nature Reserve, where reindeer grazing have been totally prohibited since 1981, and strongly restricted since 1950s. The six other sites were located in other species rich hotspot sites standardized to be as similar to the dolomite-influenced sites in Malla Strict Reserve as possible but varying in reindeer densities commonly found in the Fennoscandian mountain chain. Each site with a habitat complex especially rich in rare vascular plants (the Dryas heath -low herb meadow complex) was systematically sampled in four plots of 2 m x 10 m. The plots were divided to 20 squares of 1 m x 1 m, and complete species lists of vascular plants were compiled for each of the squares. The first DCA (detrended correspondence analysis) axis was strongly related to an index of reindeer grazing, indicating that grazing has a strong impact on the composition of the vegetation. None of the characteristics indices of biodiversity (species richness, evenness or Shannon-Wiener H') was correlated with reindeer density. The local abundances of categories consisting of relatively rare plants (Ca favored plants and red listed plants of Finland) showed significant, positive correlation with the intensity of reindeer grazing. We conclude that even though the density of reindeer has no influence on the total species richness or diversity of vascular plants, reindeer may still be important for regional biodiversity as it seems to favour rare and threatened plants. Moreover, our results imply that standard diversity indices may have limited value in the context of conservation biology, as these indices are equally influenced by rarities and by trivial species.

Review on the Geographic and Elevational Distribution of the Mountain Long-Eared Bat Plecotus Macrobullaris, Completed by Utilising a Specific Mist-Netting Technique

“…The alpine heaths and grasslands above the tree-line are the main grazing habitats for domestic reindeer, and it is obvious that reindeer grazing has been a key factor affecting the composition of the vegetation and the abundance of species (Suominen & Olofsson 2000, Olofsson & Oksanen 2003.…”

Mountains of Kilpisjarvi Host An Abundance of Threatened Plants in Finnish Lapland

“…This is especially pronounced for arctic-alpine plants and for plants favoured by limerich bedrock. The occurrence of lime-favouring arctical pine plants is strongly concentrated within a relatively small 'hotspot' area in the eastern and interior part of the mountain chain, stretching from the Abisko area in northernmost Swedish Lapland to Altafjord in Finnmark, Norway (Olofsson & Oksanen 2005). The taxon richness of vascular plants in the area of the present study is highest in the Caledonian mountain range of Scandinavia, based on the Atlas Florae Europaeae distribution grids (Väre et al 2003).…”

“…Northernmost Fennoscandia is characterized by large variations in species richness, which is especially pronounced for arctic-alpine plants and for plants favoured by lime-rich bedrock. To illustrate the general pattern of this variation, Olofsson & Oksanen (2005) compiled a map of the occurrence of limefavouring arctic-alpine vascular plant species in different northern grids of the Atlas Florae Europaeae (Jalas et al 1972(Jalas et al -1999. The highest species richness is found on the grid encompassing the surroundings of Lake Kilpisjärvi, but values obtained for the surroundings of Torneträsk in Sweden and Reisadalen in Norway are only marginally lower.…”

Future forest distribution on Finnmarksvidda, North Norway

“…However, disturbances such as moth outbreaks ) and winter warming (Bokhorst et al 2009, Bjerke et al 2014) might also lead to more rapid birch forest growth as it may damage crowberry Em petrum hermaphroditum, which possibly prevent birch seeds germinating and sprouting (Nilsson & Zackrisson 1992, Bråthen et al 2010. In contrast to the described effects of reindeer grazing on lichen pastures in the winter grazing areas, the effects on herbs, willows and trees in summer pasture areas are quite different, as reindeer can stabilize and move the treeline downwards (Cairns & Moen 2004, Cairns et al 2007, and also promote the growth of rare mountain plants (Olofsson & Oksanen 2005). Prevailing disturbance regimes in the coastal parts of Finnmark are to a large extent species-specific, but directly or indirectly related to climate (Hofgaard et al 2013).…”