Abstract
This proposal is a development of previous research funded by Formas, aiming at providing basic knowledge of how recruitment processes influence species diversity of fragmented habitats with high conservation values, semi-natural grasslands and species-rich deciduous forests. In the present project, we intend to focus on a hitherto rather neglected process, namely the propagule pressure that any target community surrounded by other vegetation types is subjected to. Propagule pressure, the inflow of diaspores from neighbouring vegetation, has the potential to cause shifts in community composition. Thus, knowledge of this process is relevant for considerations of a landscape perspective of conservation, but also for an enhanced understanding of species invasions and how long term changes in conditions related to soil and climate may impact on these habitats. Two basic models of community assembly will be examined: niche vs dispersal assembly. The approach is to use natural gradients in community composition of grasslands and deciduous forest, and examine the niche structure of these communities using plant functional traits. Propagule pressure will be experimentally manipulated, and the resulting recruitment will be recorded during 3 years. The project will be conducted within a PhD programme, and in international collaboration.
Sweden