Abstract
Recent studies have increased our knowledge on how reindeer affect species richness at small spatial scales. However, we do not know how reindeer grazing affect species richness at large spatial scales. The relationship between species richness and area is particularly important as it holds out a prospect of predicting species richness at large scales from data gathered relatively inexpensive at much smaller scales. However, predicting effects of grazing on species richness at large spatial scales from small-scale studies is by no means a simple task as different processes determine species diversity at different spatial scales. I will here test the hypothesis that reindeer grazing increase species richness at small spatial scales but decrease species richness at large spatial scales. Moreover, I will also study whether the effect of reindeer on species richness at different spatial scales driven by their effect on spatial heterogeneity of plant biomass and nutrient availability. A combination of small-scale manipulations, natural experiments and descriptive studies will be used. These studies will increase our knowledge on how reindeer affect species richness at larger spatial scales. This increased knowledge is essential to fulfill the environmental targets decided by the Swedish government.
Sweden