Abstract
Boreal plant communities are nutrient-limited and dominated by dwarf-shrub species. Parasitic fungi play a key role in these communities affecting species composition, community structure, and vegetation change. How these organisms respond to abiotic factors constitute the key for understanding how these communities respond to global change. It is predicted that increased nitrogen deposition will result in increased disease severity triggering vegetation change, while both increased temperature and decreased snow depth will have the opposite effect. Still many issues remain unclear. For example different host-pathogen associations show individualistic responses to increased nitrogen deposition. The long-term consequences of that remain unclear. Another issue is whether increased nitrogen deposition will result in increased incidence of diseased berries. The corne stones in the project are some permanent long-term field experiments (established in 1995, 1996, and 2003). They constitute the prerequiste for the possibility to separate short-term, transient responses from long-term effects. In addition small-scale experiments will be used to address responses of individual host-pathogen associations. The project is planned for a 4-yr period and is thereafter terminated. I apply for funding for the maintanence of the long-term experiments, and for field and lab work. I also apply for funding of a PhD student.
Sweden