!"en ###$%&'(()'*#+ Contents 0 Acknowledgements .....................................................................................................1 1 List of Included Publications ..................................................................................2 2 Summary...................................................................................................................3 3 Introduction..............................................................................................................5 3.1 Terms and Definitions .................................................................................................6 4 Quantity of Plant Species Richness ........................................................................7 4.1 How Many Species? ....................................................................................................7 4.2 Geographic Distribution, Hotspots and Endemism .....................................................8 5 Scales: Taxonomic, Spatial and Temporal Scale ................................................