Bücher von Rodica Pena

European beech (Fagus sylvatica L.) is the dominant tree species of the potential natural vegetationin Central Europe. In temperate forest ecosystems not affected by anthropogenic activities, nitrogenis a growth-limiting factor. Beech trees form mutualistic associations with ectomycorrhizal (EM)fungi, which have the ability to take up different inorganic and organic nitrogen-containingcompounds and to improve plant nitrogen-status. EM fungal communities and functions are thereforeof major interest for tree nutrition.In this work, the functional diversity of beech ectomycorrhizas with respect to nitrogen (N) andcarbon (C) availability has been investigated. The following hypotheses were tested:Mobilization of litter-derived nitrogen by EM fungi differs amongst fungal species in the firstphase of litter decomposition.Long-distance EM exploration types accumulate more litter-derived N than short distanceones, because of their higher accessibility to the litter.Differences in litter-derived N accumulation between EM fungal species decrease over timewith the increasing availability of litter-released N via the soil.Functional differences exist between EM fungal species with respect to nitrogen uptake andprocessing.