Abstract
Although short-term effects are minor, reindeer can still have large indirect effects on the vegetation by influencing soil temperature, nutrient turnover and competition between plants. The vegetation in the Scandinavian mountains is expected to change due to a warmer climate and many species have already increased their altitudinal range margins as the last decades have been extremely warm. How reindeer will interact with climate induced vegetation changes are poorly studied. I will study these questions in 48 exclosures that were built 1998 in four different locations in northern Scandinavia. Large mesh size reindeer exclosures and small mesh size exclosures that excludes voles and lemmings were built in two contrasting habitats (forest & open tundra). Four species of trees were sown in each exclosure. I will study how reindeer influence plant community composition, dynamics of carbon and nitrogen and the regeneration and survival of trees and other plants that are expected to be favored by a warmer climate. Field studies will be combined with mathematical modeling of carbon and nitrogen dynamics. Results from these theoretical and empirical studies will be important for evaluating the sustainability of present reindeer management regimes and for understanding how reindeer interact with climate-induced vegetation changes. These studies will reveal if reindeer can prevent the increase of shrubs and trees that are expected to threaten tundra heathlands in the future.
Sweden